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Item 1. Business

2026-03-16 compared with 2025-03-06 · 359 added, 237 removed, 460 unchanged (56% of the section changed)

We are a clinical-stage, oncology-focused biopharmaceutical company developing novel, masked, conditionally activated biologics designed to be localized to the tumor microenvironment.

We aim to build a commercial enterprise to maximize our impact on the treatment of cancer.

By pioneering a novel class of localized biologic drug candidates, powered by our PROBODY ® therapeutic technology platform, we lead the field of masked, conditionally activated oncology therapeutics and have established biologics localization as a strategic area of research and development.

Our vision is to transform lives with safer, more effective therapies with the goal of addressing major unmet needs in oncology.

Our proprietary, versatile, multi-modality PROBODY technology platform is designed to enable conditional activation of biologic therapeutic candidates within the tumor microenvironment while minimizing drug activity in healthy tissues and circulation.

Our platform is built on a strong foundation of tumor biology expertise including deep knowledge of tumor-associated enzymes known as proteases.

Proteases are tightly controlled in normal tissues but often dysregulated and active in the tumor microenvironments where they play important roles in cancer cell migration, invasion and metastasis.

Leveraging our deep scientific knowledge, we conceived of and constructed our PROBODY therapeutic platform which allows us to genetically engineer biologic therapeutic candidates to contain protease-cleavable masks.

Our masking strategy is designed to reduce binding of biologic drugs to their targets until the mask is removed by proteases in the tumor microenvironment, providing more selective targeting of the tumor.

We are employing our PROBODY therapeutic platform technology to address some of the biggest challenges in oncology biologics research and development.

These include the validation of potential new targets for antibody-drug conjugates (“ADCs”), opening therapeutic window for novel T-cell engagers (“TCEs”) targeting solid tumors, and increasing the therapeutic index for immune modulators such as cytokines.

We have utilized our PROBODY therapeutic platform to build a promising clinical-stage pipeline of potential first-in-class and best-in-class clinical-stage molecules.

CX-2051 is an investigational, conditionally activated ADC targeting epithelial cell adhesion molecule (“EpCAM”) and is CytomX’s lead program currently in Phase 1 focused in advanced metastatic colorectal cancer (CRC).

CX-801 is an investigational, masked version of interferon alpha-2b (“IFNα2b”) in Phase 1 initially focused in advanced melanoma.

CX-904, a conditionally activated, PROBODY ® TCE, targeting the epidermal growth factor receptor (“EGFR”) on tumor cells and the CD3 receptor on T cells, was being developed by CytomX in Phase 1 dose escalation as part of a global co-development alliance with Amgen.

Our current clinical-stage molecules address targets or mechanisms that have been previously validated as having anti-cancer activity but that have been limited in their utilization due to systemic toxicities.

We have incorporated our broad masking and conditional activation expertise, and ongoing clinical trial learnings, to optimize predicted therapeutic index and the clinical potential of these promising agents through tumor localization.

We also have a pre-clinical pipeline, including multiple collaboration programs.

CytomX has established and has ongoing research collaborations with partners Amgen, Astellas, Bristol Myers Squibb, Moderna, and Regeneron with the majority of these programs currently focused on TCEs.

We are a clinical-stage, oncology-focused biopharmaceutical company dedicated to developing innovative therapies to address major unmet need in oncology.

CytomX has led the field of conditionally activated, masked biologics through the development of its PROBODY technology platform.

This versatile, multi-modality platform is built on a strong foundation of tumor biology expertise, including deep knowledge of tumor-associated enzymes known as proteases.

Our masking strategy is designed to reduce binding of biologic therapeutics to their targets until the mask is removed by proteases in the tumor microenvironment, providing more selective targeting of the tumor and optimizing the predicted therapeutic index of our clinical candidates.

CytomX’s experience and leadership with the PROBODY platform for over 15 years has led to a highly focused strategy for the application of its technology in product development that has resulted in a current pipeline of novel clinical-stage and pre-clinical stage programs.

In identifying and designing potential PROBODY therapeutics, we evaluate the following:

Drug targets that have been validated previously as having clinical anti-tumor activity, but have been limited in their utility due to expression and toxicity in healthy tissues.

• Indication:

The significance of the clinical unmet need that may be addressed if the target could be targeted systemically and unlocked through masking.

• Effector Mechanism:

the PROBODY platform is highly versatile and is being applied to a wide range of modalities including antibody drug conjugates (“ADCs”), T-cell engagers (“TCEs”), and cytokines.

In PROBODY therapeutic design, the goal is to align the selected indication with the most validated drug modality (e.g.

ADC, TCE) and cancer cell killing mechanism (e.g.

cytotoxic payload) to maximize the potential for clinical activity.

CytomX’s two current clinical programs, varsetatug masetecan (“Varseta-M”) and CX-801 are in Phase 1 clinical development and are examples of our focused program development strategy.

We aim to continue to advance our clinical pipeline towards later stage development and ultimately build a commercial enterprise to maximize our impact on the treatment of cancer.

Varsetatug Masetecan (Varseta-M)

Our most advanced clinical-stage program is Varseta-M, an investigational, conditionally activated antibody-drug conjugate (“ADC”) targeting epithelial cell adhesion molecule (“EpCAM”).

Varseta-M is initially focused on the lead indication of colorectal cancer (“CRC”).

Varseta-M is designed to bring the promise of ADCs, which have made a meaningful clinical difference in other solid tumors such as lung and breast cancer, to CRC by leveraging EpCAM as a potentially ideal CRC antigen to target this disease.

Varseta-M is a high affinity EpCAM antibody that is designed to preferentially bind EpCAM in the tumor microenvironment and minimize toxicities in healthy tissues, which have limited prior attempts in the field to target EpCAM systemically.

Varseta-M is armed with a topoisomerase-1 inhibitor payload.

Topoisomerase-1 inhibitors are known to have clinical activity in CRC, including irinotecan chemotherapy which is a standard component of the approved standard of care in CRC.

EpCAM is a high potential oncology target based on its documented high expression in many solid tumors, including CRC where it was first discovered due to its very high and uniform expression.

Historically, previous efforts across the drug development landscape to target this antigen systemically have been limited by dose-limiting toxicities.

For example, high affinity EpCAM antibodies were limited by pancreatitis and liver toxicities and discontinued.

However, EpCAM has been validated as a cancer target, including by the drug KORJUNY ® , which is approved for the treatment of malignant ascites in Europe.

KORJUNY ® , however, must be given directly into the peritoneum due to systemic toxicity, but its approval provides evidence that local delivery of an EpCAM therapeutic to the tumor can be effective.

The Varseta-M payload is a topoisomerase-1 inhibitor licensed from AbbVie (formerly ImmunoGen), tailored to have anti-tumor activity against EpCAM-expressing cancer types.

The payload-antibody linker is specifically designed to drive bystander killing of neighboring tumor cells, contributing to robust anti-tumor activity.

Overall, the design of Varseta-M seeks to establish a clinically meaningful therapeutic window for the systemic treatment of patients with EpCAM-expressing cancers, for the first time.

Varseta-M is designed to potentially address a broad range of EpCAM-expressing tumors, but is initially focused in CRC which is one of the largest unmet needs in oncology with over 1.9 million cases diagnosed annually around the world.

It is also a disease that is expected to grow and estimated that there will be over 3 million cases globally by 2040.

CRC is the second leading cause of cancer death worldwide and has a 5 year survival rate in the metastastic setting of only 13%.

CRC is also the leading cause of cancer death in the U.S.

for patients under the age of 50 and has been growing in incidence in younger patients over the last 3 decades.

Varseta-M clinical development is initially being focused on late-line metastatic CRC where there is significant unmet need and treatment options are highly inadequate.

In third line or later metastatic CRC, patients have typically progressed through multiple chemotherapy-based regimens.

Later stage treatment is limited to therapies that provide single digit percentage response rates, median progression free survival of 2 to 5.6 months and overall survival outcomes ranging from approximately 6 to 11 months.

It is estimated that there are more than 35,000 patients in the U.S.

with 3 rd line or later metastatic CRC, with the number expected to grow over the next decade.

While Varseta-M is initially being developed in late-line metastatic CRC, the program was developed with the vision to help a broad population of metastatic CRC patients, including those in the first- and second-line settings.

Given Varseta-M’s mechanism of action, our longer-term development vision is to make Varseta-M a core component of the CRC treatment landscape in earlier lines of therapy, consistent with the development strategy that has been employed for other solid tumor ADCs.

We plan to pursue combination strategies to progress this vision to move Varseta-M to earlier lines of therapy starting in 2026.

Additionally, given the broad solid tumor expression profile of EpCAM, Varseta-M has the potential to be an innovative new treatment option in a wide range of solid tumors.

High expression of EpCAM has been documented in other tumors such as gastric, gastroesophageal, pancreatic, ovarian, endometrial, non-small cell lung and triple negative breast cancers.

We plan to potentially initiate development in indications outside of CRC in the second half of 2026, with the ultimate vision to develop Varseta-M as a pan-tumor therapy.

Varsetatug Masetecan Development

The investigational new drug application (“IND”) for Varseta-M was allowed to proceed by the FDA in January 2024, and a Phase 1 clinical trial in patients with EpCAM-expressing solid tumors, with an initial focus on metastatic CRC, commenced in April 2024.

No pre-screening of CRC patients by EpCAM expression has been conducted due to the anticipated high and uniform EpCAM expression in CRC.

As of May 2025, the Phase 1 study had reached the seventh dose escalation level and had enrolled only mCRC patients.

In May 2025, we announced positive interim Phase 1 data as of an April 7, 2025 data cutoff in advanced metastatic CRC.

The data encompassed results from 25 CRC patients treated with Varseta-M at 5 dose levels ranging from 2.4 mg/kg to 10 mg/kg, administered every three weeks (“Q3W”).

The 2.4 mg/kg and 4.8 mg/kg doses were single patient dose escalation cohorts not anticipated to be therapeutically active.

At the 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg doses, 23 patients were treated, 18 of whom were efficacy evaluable, having had at least one post-baseline tumor assessment as of the data cutoff.

Patients enrolled in the study at the time of data cutoff had previously received a median of 4 prior lines of therapy and all patients had previously been treated with irinotecan.

64% of patients had liver metastases, 64% had KRAS mutations, and 96% were microsatellite stable.

Patients were not preselected based on EpCAM expression levels.

As of the data cutoff, 18 patients were efficacy-evaluable at doses of 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg Q3W.

Five of eighteen (28%) patients demonstrated confirmed partial responses per RECIST v1.1.

Three of seven (43%) efficacy evaluable patients at the dose of 10 mg/kg Q3W demonstrated confirmed partial responses per RECIST v1.1.

Seventeen of eighteen patients (94%) had disease control, defined as having an objective response or stable disease.

Preliminary median progression free survival (“PFS”) was 5.8 months as of the data cutoff with 10 of 18 patients remaining on study treatment.

As of the data cutoff, 25 patients were evaluable for safety.

Varseta-M was generally well-tolerated as of the data cutoff with manageable adverse events, with no dose limiting toxicities.

Most treatment related adverse events (“TRAEs”) were Grade 1 or Grade 2 in severity.

The most common reported TRAEs were diarrhea (18 patients, 5 Grade 3), nausea (11 patients, 1 Grade 3), vomiting (8 patients, No Grade 3), fatigue (8 patients, 1 Grade 3), anemia (5 patients, 3 Grade 3), hypokalemia (3 patients, 1 Grade 3), neutrophil count decrease (2 patients, 2 Grade 3) and neutropenia (2 patients, 1 Grade 3).

TRAEs included serious adverse events (“SAEs”) in 5 patients (1 Grade 2, 4 Grade 3).

The SAEs included Grade 3 Diarrhea (1 patient), Grade 3 Anemia (1 patient), Grade 3 colitis (1 patient), Grade 3 Diarrhea and Acute kidney injury (1 patient) and Grade 2 Asthenia (1 patient).

No Grade 4 or 5 TRAEs were observed as of the April 7, 2025 data cutoff.

No events of interstitial lung disease or febrile neutropenia were reported as of the data cutoff.

On August 13, 2025, we announced that a single Grade 5 treatment-related acute kidney injury occurred in a patient with a complex medical history, including having a solitary kidney.

The Grade 5 event was believed to be secondary to nausea, vomiting and diarrhea.

We reported the event to the FDA in accordance with regulatory requirements.

The CTMX-2051-101 Safety Review Committee reviewed the event and supported continued study execution.

Based on the positive interim Phase 1 dose escalation data in May 2025, dose expansions were initiated at the dose levels of 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg, administered Q3W and are currently ongoing.

Varsetatug Masetecan March 2026 Interim Data Update from Phase 1 Dose Expansions

In March 2026, we announced positive interim results from the ongoing Phase 1 dose expansions as of a January 16, 2026 data cutoff date.

As of the data cutoff, a total of 93 patients with late-line metastatic CRC had been enrolled in the study.

patients were enrolled across the Phase 1 expansion dose range of 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg of which 56 were efficacy evaluable as of the data cutoff.

Starting in October 2025, the expansion doses of 8.6 mg/kg and 10 mg/kg were prioritized for dose optimization utilizing optimized adverse event management guidelines and adjusted ideal body weight (AIBW) dosing.

20 patients had been enrolled in expanded dose optimization as of the January 16 th data cutoff towards an enrollment goal of 40 patients.

Patients enrolled in the study had previously received a median of 3 prior lines of therapy in the metastatic setting and 96% of patients had previously been treated with irinotecan.

76% of patients had liver metastases and 71% had KRAS mutations.

Patients were not preselected based on EpCAM expression levels.

All patients with evaluable tumor biopsies had high EpCAM levels as measured by immunohistochemistry.

As of the data cutoff, 56 patients were efficacy-evaluable at the expansion doses of 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg Q3W.

Median duration of follow-up across the efficacy-evaluable patient population was approximately 8 months.

Efficacy data across the Phase 1 Expansion doses are summarized below in Table 1.

Varseta-M Efficacy Summary by Phase 1 Expansion Dose

Confirmed Overall Response Rate (cORR)

Median Progression Free Survival (PFS)

Disease Control Rate (DCR)

At the 8.6 mg/kg dose, the confirmed response rate was 20% with an estimated median PFS of 6.8 months and at the 10 mg/kg dose, the confirmed response rate was 32% with an estimated median PFS of 7.1 months.

The disease control rate was 88% (49/56) across the expansion doses of 7.2 – 10 mg/kg.

The doses of 8.6 mg/kg and 10 mg/kg have been prioritized for further evaluation with the goal of selecting a dose or doses for a registrational study.

Dose optimization at 8.6 mg/kg and 10 mg/kg utilizing AIBW dosing and updated prophylaxis for adverse event management is ongoing.

At the doses of 11 mg/kg Q3W and 12 mg/kg Q3W, which were not expanded for further evaluation, the overall response rate was 30% (3/10).

As of the data cutoff, 93 patients were evaluable for safety including 80 patients across the expansion dose range of 7.2 mg/kg to 10 mg/kg.

Varseta-M’s safety profile was generally consistent with data presented in Phase 1 dose escalation.

Most TRAEs were Grade 1 or Grade 2 in severity.

No interstitial lung disease, febrile neutropenia or pancreatitis were observed.

The most common TRAE was diarrhea which was generally manageable and reversible.

In Phase 1 dose expansions starting in Q2 2025, prophylactic strategies for diarrhea management were investigated.

In dose optimization starting in Q4 2025, an updated prophylaxis regimen of anti-motility medication (loperamide or diphenoxylate/atropine) plus budesonide was implemented.

2 In the 20 patients receiving the updated prophylactic regimen at the Varseta-M expansion doses of 8.6 mg/kg and 10 mg/kg, Grade 3 diarrhea was 10%.

Overall, as of the January 16 th 2026 data cutoff, in the 80 patients treated at expansion and optimization doses ranging between 7.2 mg/kg to 10 mg/kg, the most common TRAEs were diarrhea (68 pts, 19 Gr 3), nausea (44 pts, 4 Gr 3), vomiting (29 pts, 3 Gr 3), fatigue (32 pts, 2 Gr 3), hypokalemia (21 pts, 13 Gr 3+), and anemia (13 pts, 6 Gr 3).

Serious treatment related adverse events (SAEs) in > 1 patient included diarrhea (4), vomiting (3), hypokalemia (3), dehydration (3), acute kidney injury (2), and colitis (2).

As previously reported on August 13, 2025, there was one treatment-related grade 5 acute kidney injury (AKI) in a patient treated at the 7.2 mg/kg dose.

The patient had a complex medical history including having a solitary kidney, and the AKI was determined to be secondary to Grade 3 nausea and Grade 2 diarrhea.

No other Grade 5 TRAEs have been reported as of the January 16 th 2026 data cutoff.

1 96% of patients with an evaluable biopsy had an H score by immunohistochemistry above 250 and all patients had H scores above 200.

2 Budesonide is a corticosteroid locally absorbed in the gastrointestinal (GI) tract.

3 8.6 mg/kg and 10 mg/kg dosed utilizing adjusted ideal body weight (AIBW).

4 Based on March 2, 2026 data snapshot .

At the 11 mg/kg and 12 mg/kg doses, there were no dose limiting toxicities in dose escalation.

The most common TRAEs across the patients in the 11 mg/kg dose (n=8) and 12 mg/kg dose (n=3) were diarrhea (9 pts, 6 GR 3), nausea, (8 pts, 0 Gr 3), and vomiting (8 pts, 1 Gr 3).

Patients treated at the 11 and 12 mg/kg doses did not receive the optimized prophylactic regimen or adjusted ideal body weight dosing.

We plan to present additional Phase 1 Varseta-M data at a medical meeting in 2026 and aim to align with the FDA in 2026 on a potential registrational study designed for Varseta-M monotherapy in advanced late-line CRC.

Additionally, in the first quarter of 2026, a Phase 1 study of Varseta-M in combination with bevacizumab has been initiated, data from which is intended to inform potential Varseta-M development in earlier lines of CRC therapy.

Initial data from the combination study with bevacizumab is expected by the first half of 2027.

A Phase 1b/2 study in combination with bevacizumab and chemotherapy is expected to start by the end of 2026.

We also continue to evaluate additional non-CRC, EpCAM positive indications for potential Varseta-M development and anticipate initiating Phase 1 expansion cohorts in one or more additional indications in the second half of 2026.

In addition to Varseta-M, our pipeline includes CX-801, an investigational, masked version of interferon alpha-2b (“IFNα2b”), currently in a Phase 1 clinical trial.

CX-801 leverages a similarly focused application of the PROBODY technology platform in that it leverages a well validated and high potential mechanism that has been limited by systemic toxicity.

Interferon-alpha was one of the first immunotherapies approved, but has fallen out of broad use because of poor tolerability.

Like EpCAM, IFNα2b has also been validated as a localized therapy, including the approved therapy ADSTILADRIN ® for bladder cancer, which is a gene therapy encoding the protein IFNα2b that is administered directly into the bladder as a single agent, providing evidence that localized IFNα2b can be a powerful and effective therapy.

IFNα2b is also an attractive cytokine in that it is a potent and multi-faceted modulator of the immune system that also has direct anti-tumor cell killing effects, providing a potentially superior approach to activating anti-tumor immune responses compared with other cytokines such as IL-2, IL-12 or IL-15.

We have applied our significant masking and protein engineering expertise to the design of CX-801, which is a dually-masked, conditionally activated version of IFNα2b that is designed to be inactive in the periphery.

The dual masks on CX-801 include a peptide mask on the cytokine domain designed to limit binding in normal tissues as well as a steric Fc mask designed to further mitigate systemic activity as well as extend CX-801’s half-life.

For CX-801, we have also employed a focused initial development strategy in Phase 1, centered on the treatment of late-line melanoma where patient options are limited once they have typically progressed through earlier line checkpoint-based therapies.

With CX-801, our initial focus is to treat patients with CX-801 in the late-line setting to potentially re-activate the immune system and improve patient outcomes in combination with PD-1 inhibition.

Our ultimate vision for CX-801 is to potentially become a cornerstone of combination immunotherapy for a wide range of tumor types, including cancers beyond melanoma.

CX-801 Development

The IND for CX-801 was allowed to proceed by the FDA in January 2024, and in the third quarter of 2024 the first patient was dosed in the CX-801 Phase 1 dose escalation study in solid tumors.

The Phase 1 dose escalation study is focused on patients with advanced melanoma.

In Phase 1 dose escalation, the study will evaluate safety, translational biomarkers and signs of clinical activity for CX-801 monotherapy and in combination with KEYTRUDA ® .

In the second quarter of 2024, CytomX announced a clinical collaboration with Merck to supply KEYTRUDA for evaluation of its combination with CX-801 in the Phase 1 study.

The Phase 1 study is currently in the fourth monotherapy dose escalation cohort.

In May 2025, Phase 1 dose escalation enrollment of CX-801 in combination with KEYTRUDA ® (pembrolizumab) in advanced melanoma was initiated and is currently enrolling at the second dose level.

Phase 1 CX-801 monotherapy translational data in melanoma patients was presented at the Society of Immunotherapy of Cancer (“SITC”) 2025 Annual Meeting in November 2025, providing evidence that the CX-801 mechanism of action was working as designed.

As of the November 8, 2025 SITC presentation, CX-801 had been generally well tolerated and the translational data presented suggest consistently increased expression of interferon-stimulated genes in paired tumor biopsies.

Upregulation of immune checkpoint genes, including PD-1 and PD-L1, and activation of immune cell populations, was also observed, providing a rationale for evaluating the combination of CX-801 and pembrolizumab.

Pharmacokinetics (“PK”) analysis also demonstrated dose-proportional exposure of CX-801, which remained predominantly in its intact (masked) form in circulation.

Phase 1 clinical data from the CX-801 and KEYTRUDA ® combination dose escalation portion of the study are expected by the end of 2026.

Preclinical PROBODY Program and Platform

In addition to our clinical program focus on PROBODY ADCs such as Varseta-M and PROBODY cytokines such as CX-801, we view the field of masked biologics as having broad potential applicability across a range of therapeutic modalities, reflecting the versatility of our platform technology.

A key focus of our current work with collaboration partners is T-cell engaging bispecific therapies (“TCEs”) where we have significant ongoing efforts with partners such as Bristol Myers Squibb and Regeneron and maintain significant research expertise.

For example, at SITC 2025, we presented preclinical data for CX-908, a dually-masked PROBODY TCE targeting CDH3 and CD3.

CX-908 potently induced tumor regressions in established breast and lung cancer xenograft tumor models and demonstrated a 100-fold improvement in tolerability, including significantly reduced cytokine release vs.

an unmasked CDH3xCD3 molecule.

We view masking as a key strategy to widen a therapeutic window for TCEs and view strategic partnering in this area as an important way to extend the reach of the PROBODY platform.

Our Corporate Strategy

We are utilizing our proprietary, versatile, multi-modality PROBODY platform to create a pipeline of biologic therapeutics to improve the lives of people with cancer and to build a long-term, multi-product, commercial biopharmaceutical company.

We are utilizing our proprietary, versatile, multi-modality PROBODY platform to create a pipeline of conditionally activatable biologic therapeutics to improve the lives of people with cancer and to build a long-term, multi-product, commercial biopharmaceutical company.

We aim to achieve this goal by:

• Advancing potentially first-in-class therapies against validated, high potential anti-cancer targets that have not yet been broadly developed as systemic therapies because of target expression in healthy tissue.

CX-2051, targeting EpCAM, is a novel ADC program in this category.

CX-2051 is designed to optimize the therapeutic index for EpCAM-expressing epithelial cancers, including colorectal cancer (CRC).

CX-2051 is armed with a cytotoxic payload (CAMP59), a camptothecin-based topoisomerase-1 inhibitor, a drug class with long history in the treatment of many cancers.

The investigational new drug application (“IND”) for CX-2051 was allowed to proceed by the FDA in January of 2024 and a Phase 1 study was initiated in the second quarter of 2024.

CX-2051 is currently in Phase 1 dose escalation.

In Phase 1 dose escalation to date, CX-2051 has demonstrated a favorable tolerability profile.

Doses predicted to be therapeutically active have been attained.

The CX-2051 Phase 1 study is ongoing and has reached the seventh dose level.

Initial CX-2051 data in advanced metastatic CRC is expected in the first half of 2025.

• Unlocking high potential immunotherapeutics that have been previously limited in their systemic use due to toxicities.

To this end, we have advanced CX-801, a masked version of interferon alpha-2b, towards the clinic.

• Advancing Varseta-M towards late phase development with an initial focus in late line metastatic CRC.

Varseta-M, targeting EpCAM, is a novel ADC program that has been uniquely unlocked by the PROBODY technology platform with the potential to be first-in-class.

Varseta-M is designed to optimize the therapeutic index for EpCAM-expressing epithelial cancers, including CRC, and has demonstrated encouraging initial data in Phase 1 to-date.

CytomX’s top priority is to advance Varseta-M towards a registrational study in late-line CRC, starting the first half of 2027.

We also are prioritizing the development of Varseta-M into earlier lines of therapy and initiated a Phase 1 combination study with Varseta-M and bevacizumab in the first quarter of 2026 with initial data expected in the first half of 2027.

We also plan to initiate a Phase 1b/2 study or Varseta-M in combination with bevacizumab and chemotherapy by the end of 2026.

CytomX also plans to explore the pan-tumor potential of Varseta-M by initiating development in indications outside of CRC in solid tumor indications that express EpCAM in the second half of 2026.

• Our strategy aims to build a multi-program clinical pipeline focused on the most promising applications of our PROBODY platform.

The versatility of the platform has enabled the targeting of multiple modalities including cytokines and to this end, we have advanced CX-801, a masked version of interferon alpha-2b, into Phase 1 development.

Interferon alpha-2b is a validated, previously approved immunotherapeutic that has demonstrated clinical activity in multiple cancer types, including in combination with checkpoint inhibitors.

Despite this previous validation, IFNα2b-based systemic therapies have been limited in their utilization due to systemic toxicities.

CX-801 is an investigational, dually masked, conditionally activated version of IFNα2b that is designed to be preferentially active in the tumor microenvironment.

The IND for CX-801 was allowed to proceed by the FDA in January of 2024 and commenced Phase 1 clinical testing in the third quarter of 2024.

The Phase 1 study is focused in advanced melanoma and will investigate CX-801 as monotherapy and in combination with PD-1 inhibitor, KEYTRUDA ® .

The Phase 1 study is currently in the fourth monotherapy dose escalation cohort where the dose of CX-801 exceeds the approved dose of the unmasked peginterferon alfa-2b (SYLATRON).

Initial Phase 1a translational data in advanced melanoma is expected in the second half of 2025.

• Leveraging the multi-modality capabilities of our platform to advance novel, high potential therapeutic formats into the clinic such as TCEs.

The field of TCEs for solid tumors has gained momentum as a strategic area of research and development but continues to be challenging for many targets due to limited therapeutic window.

We believe our PROBODY platform is well-suited to address this challenge by localizing the potent anti-tumor activity of TCEs and potentially limiting systemic toxicities.

We have a broad effort in the field of TCEs including active programs with our partners, Astellas, Regeneron, Bristol Myers Squibb and Amgen.

• Partnering with leading global biopharmaceutical companies to access capital, additional resources and expertise, as well as increase the number of PROBODY therapeutic candidates being advanced into clinical studies.

The CX-801 Phase 1 study commenced monotherapy dosing in the third quarter of 2024 and has demonstrated initial translational data that supports the PROBODY therapeutic design and mechanism of action as a single agent.

The program development strategy for CX-801 is focused on combinations with checkpoint inhibitors and a Phase 1 dose escalation study of CX-801 in combination with KEYTRUDA ® (pembrolizumab) focused exclusively in advanced melanoma is currently enrolling at the second dose level.

A company priority for CX-801 is to report in Phase 1 clinical data from the CX-801 and KEYTRUDA ® combination by the end of 2026.

Our ultimate vision is to position CX-801 as a cornerstone of combination immunotherapy for a wide range of tumor types, including tumors that are refractory to prior checkpoint inhibition or that have been historically insensitive to immunotherapy.

• Leveraging our integrated research and development capabilities and broad multi-modality applications of our platform, we aim to build a multi-program pipeline and continue to extend the reach of our technology.

Our strategy aims to advance programs either as wholly-owned programs or with partners to maximize our potential impact in oncology.

We have successfully partnered with leading global biopharmaceutical companies to access capital, additional resources and expertise, as well as to increase the number of PROBODY therapeutic candidates being advanced into clinical studies.

We currently have several strategic alliances with major multinational drug companies, including Amgen, Inc.

6 unchanged sentences

CytomX’s pipeline spans pre-clinical and clinical programs and includes a range of therapeutic formats including antibody drug conjugates, T-cell engagers, immunotherapies, and mRNA.

The table below depicts the current status of our clinical-stage, conditionally activated product candidates, including potential milestones in 2025.

Our current lead clinical programs focus on validated targets, for which substantial potential remains if they can be improved by widening the therapeutic index.

The table below depicts the current status

of our clinical-stage, conditionally activated product candidates, including potential milestones in 2026.

Our current lead clinical programs are focused applications of our PROBODY platform, leveraging validated targets that have significant potential in indications of high unmet need.

By employing tailored masking strategies and choosing an optimal effector function (e.g.

ADC, cytokine, TCE), each program has been designed to optimize therapeutic window in order to address large unmet needs in oncology markets.

CytomX Pipeline of Clinical Stage PROBODY Therapeutics and 2025 Potential Milestones

as of March 2025

CX-2051 was licensed from ImmunoGen (acquired by AbbVie in 2024)

CX-2051, A PROBODY Topoisomerase-1 ADC Targeting EpCAM

The field of ADCs has made tremendous progress in recent years in hematologic and increasingly, in solid tumors.

CytomX Pipeline of Clinical and Preclinical PROBODY Therapeutics and 2026 Potential Milestones

*CytomX Commercial Rights include wholly-owned molecules or molecules for which CytomX has development and commercial control

Varseta-M was licensed from ImmunoGen (acquired by AbbVie in 2024)

Varsetatug Masetecan, A PROBODY Topoisomerase-1 ADC Targeting EpCAM

The field of ADCs has made tremendous progress in recent years in hematologic cancers and increasingly, in solid tumors.

ADCs are making a difference for patients across a wide range of tumors and continue to move earlier in the treatment paradigm across certain malignancies.

The success of the field has driven increased interest in this modality including the need to identify novel ADC targets as well as optimized linker payloads.

EpCAM is a strategic pan-tumor target with high potential across many tumor types.

EpCAM is a potential pan-tumor target with promise across many tumor types.

EpCAM has been clinically validated with locally administered, approved cancer therapies.

However, efforts to generate systemic anti-EpCAM therapeutics have, to date, not been successful due to toxicities in epithelial tissues.

CX-2051, a conditionally activated ADC, is designed to optimize the therapeutic index for EpCAM-expressing epithelial cancers, including colorectal cancer.

CX-2051 is armed with a cytotoxic payload (CAMP59), a camptothecin-based topoisomerase-1 inhibitor, a drug class with long history in the treatment of many cancers.

The payload-PROBODY linker in CX-2051 is optimized for bystander effect, that is, the killing of neighboring cancer cells.

Preclinically, CX-2051 has demonstrated a wide predicted therapeutic index, as well as strong activity and tolerability in multiple preclinical models, including in colorectal cancer.

In preclinical safety studies in cynomolgus monkeys, CX-2051 was tolerated at doses at least six times higher than an unmasked EpCAM ADC.

Based on the wide predicted therapeutic index, we believe CX-2051 has the potential to address a broad range of EpCAM expressing solid tumors and make a significant difference for patients.

The preclinical results for CX-2051 were presented at the World ADC Conference in 2023.

The IND for CX-2051 was allowed to proceed by the FDA in January 2024 and the Phase 1 study of CX-2051 started in the second quarter of 2024 with an initial focus in CRC.

CX-2051 is currently in Phase 1 dose escalation.

In Phase 1 dose escalation to date, CX-2051 has demonstrated a favorable tolerability profile and doses predicted to be therapeutically active have been attained.

The CX-2051 Phase 1 study has reached the seventh dose level with initial data in advanced metastatic CRC expected in the first half of 2025.

Varseta-M, a conditionally activated ADC, is designed to optimize the therapeutic index for EpCAM-expressing epithelial cancers, including colorectal cancer.

Varseta-M is armed with a cytotoxic payload (“CAMP59”), a camptothecin-based topoisomerase-1 inhibitor, a drug class with a long history in the treatment of many cancers.

The payload-PROBODY linker in Varseta-M is optimized for bystander effect, that is, the killing of neighboring cancer cells.

Preclinically, Varseta-M has demonstrated a wide predicted therapeutic index, as well as strong anti-tumor activity and tolerability in multiple preclinical models, including in colorectal cancer.

In preclinical safety studies in cynomolgus monkeys, Varseta-M was tolerated at doses at least six times higher than an unmasked EpCAM ADC.

Based on the wide predicted therapeutic index in preclinical studies, and clinical results to date, we believe Varseta-M has the potential to address a broad range of EpCAM-expressing solid tumors and make a significant difference for patients.

The IND for Varseta-M was allowed to proceed by the FDA in January 2024 and the Phase 1 study of Varseta-M started in the second quarter of 2024 with an initial focus in CRC.

Based on positive interim Phase 1 dose escalation data presented in May 2025, dose expansions were initiated at the dose levels of 7.2 mg/kg, 8.6 mg/kg, and 10 mg/kg, administered Q3W and are currently ongoing.

In March 2026, we announced positive interim data from Phase 1 dose expansions in 93 patients with advanced CRC as of a January 16, 2026 data cutoff.

We plan to present additional Phase 1 data for Varseta-M at a medical meeting in 2026 and aim to align with the FDA in 2026 on a potential registrational study designed for Varseta-M monotherapy in advanced CRC.

Additionally, in the first quarter of 2026, a Phase 1 study of Varseta-M in combination with bevacizumab was initiated, data from which is intended to inform potential Varseta-M late phase development in earlier lines of CRC therapy.

Initial data from the combination study with bevacizumab is expected by the first half of 2027.

We also plan to initiate a Phase 1b/2 study of Varseta-M in combination with bevacizumab and chemotherapy by the end of 2026.

We also continue to evaluate additional non-CRC, EpCAM expressing indications for potential Varseta-M development and anticipate initiating Phase 1 expansion cohorts in one or more additional target indications in the second half of 2026.

CX-801, A PROBODY Cytokine, Interferon alpha-2b ( “ IFNα2b ” )

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The preclinical profile of CX-801 was presented at SITC 2023.

The IND for CX-801 was allowed to proceed by the FDA in January 2024 and Phase 1 dose escalation started in the third quarter of 2024 with an initial focus in advanced melanoma.

The Phase 1 study is currently in the fourth monotherapy dose escalation cohort where the dose of CX-801 exceeds the approved dose of the unmasked peginterferon alfa-2b (SYLATRON).

The Phase 1 dose escalation study will evaluate safety and signs of clinical activity for CX-801 monotherapy and in combination with KEYTRUDA.

Initial Phase 1a dose escalation data focused on translational biomarkers are expected in the second half of 2025.

CX-904, A PROBODY TCE Targeting EGFR and CD3

We have extended our PROBODY platform to the promising modality of TCEs.

Conventional TCEs are a highly potent therapeutic modality designed to direct the tumor cell killing activity of cytotoxic T cells to tumors.

TCEs such as the BiTE ® molecule, Blincyto ® , a CD19-directed TCE commercialized by Amgen, have shown clinical activity in hematologic malignancies, but broad development of TCEs for solid tumor indications has been challenging.

Due to their high potency, TCEs can target normal tissues with low antigen expression, which may result in significant toxicity.

We believe these toxicity challenges could be addressed using our PROBODY

platform by localizing the activity of TCEs to the tumor microenvironment thereby increasing the therapeutic index for TCEs in solid tumors.

Our most advanced program in this modality was CX-904, a conditionally activated epidermal growth factor receptor-CD3 (“EGFRxCD3”) TCE, which we partnered with Amgen.

The strategy for CX-904 is to utilize EGFR expression as an "address" to localize T-cells to solid tumors.

EGFR is a broadly expressed, highly validated antibody target with multiple approved therapies on the market.

CX-904 is a bispecific antibody targeting EGFR and CD3 that is masked on both binding domains to potentially mitigate both EGFR and CD3 related toxicities.

CX-904 has been optimized in preclinical studies and we believe may result in a novel approach to address EGFR positive solid tumors.

In preclinical studies, our PROBODY EGFRxCD3 TCE therapeutics demonstrated anti-tumor activity and better tolerability when compared to EGFRxCD3 TCEs without PROBODY masking.

In May 2022, the first patient was dosed in a Phase 1 study in patients with advanced solid tumors.

In May 2024, we disclosed initial data based on an April 16, 2024 data cutoff from the Phase 1 clinical study that demonstrated that CX-904 had been generally well tolerated and showed initial signs of antitumor activity.

As of the data cutoff, the CX-904-101 study had enrolled 35 patients with advanced metastatic solid tumor types that are generally known to express EGFR, including pancreatic, colorectal (CRC), non-small cell lung cancer (NSCLC), head and neck squamous cell carcinoma (HNSCC), gastric, and esophageal cancers.

Patients enrolled in the study were heavily pre-treated and had a median of 4 prior lines of therapy.

As of the cutoff date, CX-904 was generally well tolerated.

There were no observed cases of cytokine release syndrome (CRS) of any grade in step-dosing cohorts as of the cutoff date.

In non-step dosing cohorts, only Grade 1 CRS was observed in patients treated at the highest dose of 6 mg.

Overall, the most common treatment-related adverse events (TRAEs) were rash, arthralgia, arthritis, pruritis, and vomiting, the majority of which were low grade, being observed in 14 (40%), 13 (37%), 5 (14%), 5 (14%) and 5 (14%) of patients, respectively.

Grade 3 adverse events were tenosynovitis (n=1), arthralgia (n=2), arthritis (n=1), rash (n=1).

As of the data cutoff, 8 patients had measurable tumor reduction per RECIST 1.1, including 2 of 6 efficacy-evaluable patients (33%) with pancreatic cancer who achieved confirmed partial responses.

Preliminary pharmacokinetic and pharmacodynamic data were consistent with the PROBODY TCE proposed mechanism of action, including maintained masking in circulation, and CD8+ T-cell margination and tumor infiltration.

As of the end of 2024, the Phase 1 study of CX-904 had enrolled over 70 patients.

The 15 mg target step-dose level had been cleared and the maximum tolerated dose had not been reached.

Based on CX-904 clinical observations to-date as well as CytomX pipeline priorities, in March 2025, CytomX and Amgen jointly decided to not further develop the CX-904 program.

The IND for CX-801 was allowed to proceed by the FDA in January 2024, and in the third quarter of 2024 the first patient was dosed in the CX-801 Phase 1 dose escalation study in solid tumors.

The Phase 1 dose escalation study is focused on patients with advanced

In Phase 1 dose escalation, the study will evaluate safety, translational biomarkers and signs of clinical activity for CX-801 monotherapy and in combination with KEYTRUDA ® .

In the second quarter of 2024, we announced a clinical collaboration with Merck to supply KEYTRUDA ® for evaluation of its combination with CX-801 in the Phase 1 study.

The Phase 1 study is currently in the fourth monotherapy dose escalation cohort.

In May 2025, Phase 1 dose escalation enrollment of CX-801 in combination with KEYTRUDA ® (pembrolizumab) in advanced melanoma was initiated and is currently enrolling at the second dose level.

Phase 1 CX-801 monotherapy biomarker data in melanoma patients was presented at the SITC 2025 Annual Meeting in November 2025.

The data presented suggest that CX-801 has been generally well tolerated to date and consistently increased expression of interferon-stimulated genes in paired tumor biopsies, suggesting preferential activity in tumors.

Upregulation of immune checkpoint genes, including PD-1 and PD-L1, and activation of immune cell populations was also observed, providing a rationale for evaluating the combination of CX-801 and pembrolizumab.

PK analysis also demonstrated dose-proportional exposure of CX-801, which remained predominantly in its intact (masked) form in circulation.

Phase 1 clinical data from the CX-801 and KEYTRUDA ® combination dose escalation portion of the study are expected by the end of 2026.

CytomX Platform and Pipeline Breadth Including Partnered Pipeline

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The mask is a peptide designed to disguise the active binding site of the biologic therapeutic to prevent it from binding to the target present on healthy tissue.

The Company has had sustained research efforts and continuous innovation around the PROBODY Platform and has invested significant resources to develop the technology.

We have had sustained research efforts and continuous innovation around the PROBODY Platform and have invested significant resources to develop the technology.

As of January 2026, our fully- and co-owned patent portfolio contains at least 245 granted patents and at least 300 pending patent applications.

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By pioneering a novel class of conditionally activated, localized biologic candidates, we are a leader in the field and have established masking as a strategic area of biologics research and development.

Our technology platform is supported by more than a decade of research and a strong

intellectual property portfolio.

More than 500 patients with diverse tumor types have been treated with our PROBODY therapeutic candidates in multiple clinical studies, providing clinical proof of concept and a deep knowledge base for translational advancement and optimization of our drug candidates and platform.

Our technology platform is supported by more than a decade of research and a strong intellectual property portfolio.

More than 500 patients with diverse tumor types have been treated with our PROBODY

therapeutic candidates in multiple clinical studies, providing clinical proof of concept and a deep knowledge base for translational advancement and optimization of our drug candidates and platform.

• A broad multi-modality technology for improvement of therapeutic index.

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Our technology has the potential to address many different molecular targets expressed by a wide range of tumor types, including targets that are difficult to address due to their widespread expression on healthy cells.

EpCAM is an example of such a target, for which we have developed CX-2051, a masked, conditionally activated PROBODY ADC.

EpCAM is an example of such a target, for which we have developed Varseta-M, a masked, conditionally activated PROBODY ADC.

• Deep knowledge of the tumor protease microenvironment.

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Our Collaborations

We believe that the PROBODY platform has broad applicability across many cancer types, biological targets and antibody modalities.

We have leveraged strategic partnering to (a) extend the reach of our technology, and (b) bring in significant non-dilutive capital into the Company.

We believe that the PROBODY platform has broad applicability across many cancer types, biological targets and therapeutic modalities.

We have leveraged strategic partnering to (a) extend the reach of our technology, and (b) bring in significant non-dilutive capital into our company.

Since 2013, we have entered into several collaborations, including with Amgen, Astellas, Bristol Myers Squibb, ImmunoGen, Moderna, and Regeneron to enable the discovery and development of certain PROBODY therapeutics.

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We were responsible for early-stage development of EGFR Products and Amgen was to be responsible for late-stage development and commercialization of EGFR Products.

Based on CX-904 clinical observations to-date as well as CytomX pipeline priorities, in March 2025, CytomX and Amgen have jointly decided to not further develop the CX-904 program.

In October 2021, we and Amgen executed an amendment to the Amgen Agreement primarily to (1) extend the target selection date for Amgen to select its additional targets for research and development, and (2) reduce the total number of milestone events and increase the total amount of milestone payments for EGFR Products.

Subsequent amendments have extended the target selection dates to March 31, 2025.

Amgen also had the right to select a total of up to three targets, including the two additional targets discussed below.

We and Amgen collaborate in the research and development of conditionally activated T-cell engaging bispecific therapies directed against such targets.

Amgen has selected one such target (the “Amgen Other Product”).

If Amgen exercises its option by March 31, 2025, it can select two such additional targets (the “Amgen Option Products” and, together with the Amgen Other Product, the “Amgen Products”).

Except with respect to preclinical activities to be conducted by us, Amgen will be responsible, at its expense, for the development, manufacture, and commercialization of all Amgen Products.

If Amgen exercises all of its options and advances all three of the Amgen Products, we are eligible to receive up to $950.0 million in upfront, development, regulatory, and commercial milestones and tiered high single-digit to low-teen percentage royalties.

Under the Amgen Agreement, we had the option to select from specified programs, an existing pre-clinical stage T-cell Engager product from the Amgen pre-clinical pipeline.

In March 2018, CytomX selected the program and this program is currently in preclinical studies.

We have the opportunity, at our expense, to convert this program to a conditionally activated T-cell Engager product, and thereafter, to be responsible for development, manufacturing, and commercialization of the product (“CytomX Product”).

In each of May 2023 and March 2024, we and Amgen executed an amendment to the Amgen Agreement to extend the target selection period for Amgen to select its additional targets.

Amgen had the right to select a total of up to three targets, including the two additional targets.

We and Amgen collaborated in the research and development of conditionally activated T-cell engaging bispecifics therapies directed against such targets.

Amgen had selected one such target (the “Amgen Other Product”).

Except with respect to preclinical activities to be conducted by CytomX, Amgen would have been responsible, at its expense, for the development, manufacture, and commercialization of all Amgen Products.

In January 2022, the IND for the EGFR product candidate (“CX-904”) was allowed to proceed by the “FDA” and the program progressed into Phase 1 dose escalation.

In March 2025, we and Amgen jointly decided to not continue CX-904 development and Amgen terminated its license to the EGFR Products.

In April 2025, the Amgen Other Product was also terminated with 60 days written notice pursuant to the Amgen Agreement.

The Amgen research collaboration remains in effect with the current scope being the preclinical TCE target (P-Cadherin or CDH3) that we selected from Amgen’s preclinical pipeline further discussed below.

At the initiation of the collaboration, we had the option to select from programs specified in the Amgen Agreement, an existing preclinical stage TCE product from the Amgen preclinical pipeline.

In March 2018, we selected the program and this program, CX-908, a PROBODY ® TCE targeting P-Cadherin (CDH3) and CD3, is currently in preclinical development.

We are responsible, at our expense, for converting this program to a conditionally activated TCE product, and thereafter, will be responsible for development, manufacturing, and commercialization of the product (“CytomX Product”).

Amgen is eligible to receive up to $203.0 million in development, regulatory, and commercial milestone payments for the CytomX Product, and tiered mid-single digit to low double-digit percentage royalties.

Astellas Pharma Inc.

In March 2020, we entered into a Collaboration and License Agreement (the “Astellas Agreement”) with Astellas, pursuant to which we and Astellas will collaborate on the research, development and commercialization of TCE (“Products”) directed to CD3 and selected tumor antigen targets using our PROBODY ® platform and other proprietary technology.

In March 2020, we entered into a Collaboration and License Agreement (the “Astellas Agreement”) with Astellas, pursuant to which we and Astellas will collaborate on the research, development and commercialization of TCE products (“Products”) directed to CD3 and selected tumor antigen targets using our PROBODY ® platform and other proprietary technology.

Under the Astellas Agreement, we granted Astellas an exclusive, worldwide, royalty-bearing license to develop and commercialize Products in all fields.

Astellas was able to select up to four targets to develop, and had an option to expand to six targets.

We will lead preclinical research and discovery activities up to clinical candidate selection for Products directed against up to four targets.

Astellas will lead preclinical and clinical development of and regulatory approval for all Products.

Astellas will be responsible for commercializing each Product, provided that we will have the option to elect to co-commercialize certain Products with Astellas in the United States, subject to the terms of a separate commercialization agreement to be entered into between us and Astellas.

Under the terms of the Astellas Agreement, we received an upfront payment of $80 million, and Astellas will be responsible for funding the cost of preclinical research and discovery activities of both parties for all Products and for funding the cost of development and commercialization of all Products worldwide.

Under the agreement, we are eligible to receive future preclinical, clinical and commercial milestones of approximately $1.2 billion.

Astellas will pay us tiered royalties on global net sales of Products from high single-digit to mid-teens percentages, subject to certain reductions.

Astellas’ royalty obligations continue with respect to each country and each Product until the later of (i) the date on which such Product is no longer covered by certain intellectual property rights, (ii) the 10th anniversary of the first commercial sale of such product in such country, and (iii) the loss of regulatory exclusivity for such Product in such country.

In addition, for a specified number of targets, at a pre-specified time prior to the initiation of the first pivotal study of a Product directed against such target, we will have an option to elect to co-fund certain subsequently initiated clinical trials for such Product.

If we opt in, we would be responsible for a pre-determined portion of the costs of such trials, subject to specified caps, deferrals and offsets.

We would then have the option to elect to co-commercialize such Products in the United States.

For any such Products, in lieu of royalties in the United States, we will receive less than 40% of the profits for such Products in the United States and tiered low double-digit to mid-teens percentage royalties on net sales of such Products outside of the United States, subject to certain reductions.

In January 2023, Astellas nominated the first clinical candidate under the collaboration which resulted in a $5.0 million milestone payment to CytomX.

In March 2024, we achieved a clinical candidate milestone for a second collaboration target and a GLP toxicology initiation milestone for the first collaboration target nominated in January 2023 under the Astellas Agreement.

Astellas selected four targets under the Astellas Agreement and the programs for three remain active.

The time period for expanding to six targets under the Astellas Agreement has expired.

We led preclinical research and discovery activities up to clinical candidate selection for the Products.

Astellas led preclinical and clinical development of and regulatory approval for the Products.

Astellas was responsible for commercializing each Product, provided that CytomX had the option to elect to co-commercialize certain Products with Astellas in the United States, subject to the terms of a separate commercialization agreement to be entered into between us and Astellas.

Under the terms of the Astellas Agreement, we received an upfront payment of $80.0 million, and Astellas was responsible for funding the cost of preclinical research and discovery activities of both parties for all Products and for funding the cost of development and commercialization of all Products worldwide.

Under the agreement, we were eligible to receive future preclinical, clinical and commercial milestones of approximately $1.2 billion.

Astellas would have paid us tiered royalties on global net sales of Products from high single-digit to mid-teens percentages, subject to certain reductions.

Astellas’ royalty obligations were to continue with respect to each country and each Product until the later of (i) the date on which such Product is no longer covered by certain intellectual property rights, (ii) the 10th anniversary of the first commercial sale of such product in such country, and (iii) the loss of regulatory exclusivity for such Product in such country.

In addition, for a specified number of the targets, at a pre-specified time prior to the initiation of the first pivotal study of a Product directed against such target, we had an option to elect to co-fund certain subsequently initiated clinical trials for such Product.

If we had opt in, we would have been responsible for a pre-determined portion of the costs of such trials, subject to specified caps, deferrals and offsets.

We would then have had the option to elect to co-commercialize such Products in the United States.

For any such Products, in lieu of royalties in the United States, we would have received less than 40% of the profits for such Products in the United States and tiered low double-digit to mid-teens percentage royalties on net sales of such Products outside of the United States, subject to certain reductions.

In January 2023, Astellas nominated the first clinical candidate under the collaboration which resulted in a $5.0 million milestone payment to us.

In March 2024, we achieved a clinical candidate milestone for a second collaboration target nomination and a GLP toxicology initiation milestone for the first collaboration target nominated in January 2023 under the Astellas Agreement.

We collected these milestone payments totaling $10.0 million in April 2024.

In the first quarter 2025, Astellas chose not to continue with IND enabling activities for the first collaboration target and prioritized the second collaboration target nominated in the collaboration.

Astellas initiated GLP toxicology studies for the second collaboration target nominated triggering a $5.0 million milestone payment to CytomX in the first quarter of 2025.

In the first quarter of 2025, Astellas chose not to continue with IND enabling activities for the first collaboration target and prioritized the second collaboration target nominated in the collaboration.

Astellas initiated GLP toxicology studies for the second collaboration target nominated triggering a $5.0 million milestone payment to us in the first quarter of 2025.

In March 2026, Astellas chose to not advance the remaining preclinical programs under the alliance, resulting in a termination of the collaboration effective in the second quarter of 2026.

CytomX is currently assessing options to advance select targets previously covered under the Astellas collaboration as part of its ongoing research and development strategy.

Bristol Myers Squibb Company

In May 2014, we and Bristol Myers Squibb entered into a Collaboration and License Agreement (the “BMS Agreement”) to discover and develop compounds for use in human therapeutics aimed at multiple immuno-oncology targets using our PROBODY therapeutic technology.

Pursuant to the BMS Agreement, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $50.0 million and estimated research and development service fees, and the Company was initially entitled to receive contingent payments of up to $25.0 million for additional targets and contingent payments for development, regulatory and sales milestones.

In addition, the Company was entitled to royalty payments in the mid-single digits to low double-digit percentages from potential future sales.

On March 17, 2017, the Company and Bristol Myers Squibb amended the BMS agreement and entered into Amendment Number 1 to Extend Collaboration and License Agreement (“Amendment 1”).

Pursuant to the BMS Agreement, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $50.0 million and estimated research and development service fees, and we were initially entitled to receive contingent payments of up to $25.0 million for additional targets and contingent payments for development, regulatory and sales milestones.

In addition, we were entitled to royalty payments in the mid-single digits to low double-digit percentages from potential future sales.

On March 17, 2017, we and Bristol Myers Squibb amended the BMS agreement and entered into Amendment Number 1 to Extend Collaboration and License Agreement (“Amendment 1”).

Amendment 1 granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize PROBODY therapeutics for up to eight additional targets.

The effective date of Amendment 1 was April 25, 2017 (“Amendment Effective Date”).

Under the terms of Amendment 1, the Company continued to have obligations to Bristol Myers Squibb to discover and conduct preclinical development of PROBODY therapeutics against any targets they chose to select during the research period under the terms of Amendment 1.

Under the terms of Amendment 1, we continued to have obligations to Bristol Myers Squibb to discover and conduct preclinical development of PROBODY therapeutics against any targets they chose to select during the research period under the terms of Amendment 1.

Pursuant to Amendment 1, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $200.0 million, estimated research and development service fees, and contingent payments for development, regulatory and sales milestones for the eight targets.

The Company was also entitled to tiered mid-single to low double-digit percentage royalties from potential future sales.

We were also entitled to tiered mid-single to low double-digit percentage royalties from potential future sales.

Amendment 1 did not change the term of Bristol Myers Squibb’s royalty obligation under the BMS Agreement.

Bristol Myers Squibb’s royalty obligation continues on a licensed-product by licensed-product basis until the later of (i) the expiration of the last claim of the licensed patents covering the licensed products in the country, (ii) the twelfth anniversary of the first commercial sale of a licensed product in a country, or (iii) the expiration of any applicable regulatory, pediatric, orphan drug or data exclusivity with respect to such product.

In February 2021, the Company and Bristol Myers Squibb amended the BMS agreement and entered into Amendment Number 2 to amend the Collaboration and License Agreement (“Amendment 2”), as previously amended by Amendment 1.

In February 2020, Bristol Myers Squibb dosed the first patient in the Part 2 cohort expansion portion of its ongoing BMS-986249 clinical study for the CTLA-4 program, which triggered a $10.0 million milestone payment to us pursuant to the terms of the BMS Agreement.

In February 2021, we and Bristol Myers Squibb amended the BMS agreement and entered into Amendment Number 2 to amend the Collaboration and License Agreement (“Amendment 2”), as previously amended by Amendment 1.

Subsequent to Amendment 2, in addition to Bristol Myers Squibb’s ongoing development of the CTLA-4 program, Bristol Myers Squibb also had the exclusive worldwide rights to develop and commercialize PROBODY therapeutics for up to five oncology targets.

Under the terms of Amendment 2, the period for target selection was extended and in 2022, all remaining targets were selected.

The Company will continue to collaborate with Bristol Myers Squibb to discover and conduct preclinical development of PROBODY therapeutics against targets selected by Bristol Myers Squibb over the estimated research period, which is projected to end in April 2025.

Pursuant to Amendment 2, the Company was eligible to receive contingent payments for development, regulatory and sales milestones.

It is also entitled to tiered mid-single to low double-digit percentage of royalties from potential future sales.

In October 2022, the Company and Bristol Myers Squibb amended the BMS Agreement and entered into Amendment Number 3 (“Amendment 3”), as previously amended by Amendment 1 and Amendment 2, to clarify the rights and restrictions of certain new proprietary antibodies that the parties exchanged.

There were no substantive changes to each party's performance obligations.

BMS-986288 is a PROBODY version of non-fucosylated ipilimumab.

The non-fucosylated Fc region of BMS-986288 enhances antigen-presenting cell-mediated T-cell priming and regulatory T-cell (Treg) modulation and is therefore intended to confer increased potency compared to fucosylated ipilimumab.

Bristol Myers Squibb was evaluating the safety and efficacy of BMS-986288 alone and in combination with nivolumab in a Phase 1/2 study in patients with certain advanced solid tumors.

In February 2023, Bristol Myers Squibb advanced BMS-986288 to Phase 2 and prioritized the molecule as its lead next-generation CTLA-4 program over its non-fucosylated CTLA-4 antibody ("BMS-986218") and the PROBODY version of ipilumamab ("BMS-986249").

The Phase 2 study for BMS-986288 included proof-of-concept studies in NSCLC and MSS CRC.

In March 2024, following a Bristol Myers Squibb corporate portfolio prioritization process, Bristol Myers Squibb notified CytomX that it does not intend to continue the development of BMS-986288 beyond the current Phase 2 study and terminated its collaboration license on the CTLA-4 target under the collaboration.

We continued to collaborate with Bristol Myers Squibb to discover and conduct preclinical development of PROBODY therapeutics against targets selected by Bristol Myers Squibb over the estimated research period, which ended in April 2025.

Pursuant to Amendment 2, we were eligible to receive contingent payments for development, regulatory and sales milestones.

We were also entitled to tiered mid-single to low double-digit percentage of royalties from potential future sales.

In October 2022, we and Bristol Myers Squibb amended the BMS Agreement and entered into Amendment Number 3 (“Amendment 3”), as previously amended by Amendment 1 and Amendment 2, to clarify the rights and restrictions of certain new proprietary antibodies that the parties exchanged.

In March 2024, following a Bristol Myers Squibb corporate portfolio prioritization process, Bristol Myers Squibb notified CytomX that it did not intend to continue the development of the PROBODY CTLA-4 program and terminated its collaboration license on the CTLA-4 target under the collaboration.

In June 2024, Bristol Myers Squibb prioritized its pre-clinical research activities under the collaboration and revised the research scope by one collaboration target.

The Company determined that it has no further obligations related to the target that was deprioritized and accounted for the reduction of the target as a modification and the related remaining unrecognized transaction price was reallocated to the remaining performance obligations.

The Company continues to be obligated to perform research work under Amendment 2 executed in February 2021 for multiple ongoing research programs.

The research term defined in Amendment 2 concludes in the second quarter of 2025, at which point, Bristol Myers Squibb is responsible for the future preclinical and clinical development of collaboration programs they chose to advance.

As of December 31, 2024, the Company is eligible to receive approximately $1.3 billion in contingent payments for development, regulatory and sales milestones for the ongoing collaboration programs.

Our research efforts on all the ongoing programs were completed in April 2025.

In May 2025, one collaboration target was also terminated with two months written notice pursuant to the BMS Agreement and two preclinical programs remain in development with Bristol Myers Squibb responsible for further advancement.

Moderna, Inc .

In December 2022, the Company entered into a Collaboration and License Agreement (the “Moderna Agreement”) with Moderna, pursuant to which the Company and Moderna will collaborate on the creation of mRNA-based conditionally-activated investigational therapies utilizing the Company's PROBODY ® therapeutic platform and Moderna’s mRNA and lipid nanoparticle technologies.

The collaboration will leverage core scientific advances at Moderna and the Company to open up the strategy of encoding potent, masked biologics through mRNA technologies, for the potential treatment of oncology and non-oncology conditions.

The Company and Moderna will collaborate on a specified number of preclinical research and discovery programs (“Moderna Collaboration Programs”) within a specified period under the Collaboration and License Agreement.

Under the Moderna Agreement, the Company granted Moderna an exclusive, worldwide, royalty-bearing license under certain Company intellectual property to develop, manufacture, commercialize and otherwise exploit certain products (“Moderna Licensed

Products”) for all human and non-human diagnostic, prophylactic and therapeutic uses, subject to certain exceptions with respect to Licensed Products within certain Collaboration Programs.

Under the terms of the Moderna Agreement, Moderna made an upfront payment to the Company of $35 million, including $5 million of pre-paid research funding.

CytomX will continue to receive research funding based on the aligned scopes of work between the two companies and CytomX will be eligible to receive future development, regulatory and commercial milestone payments of up to $1.2 billion for all Moderna Licensed Products in total under the Moderna Agreement.

Moderna will pay the Company tiered royalties on global net sales of Moderna Licensed Products from high single digit to low-teen percentages, subject to certain reductions.

In December 2022, we entered into a Collaboration and License Agreement (the “Moderna Agreement”) with Moderna, pursuant to which we and Moderna will collaborate on the creation of mRNA-based conditionally-activated investigational therapies utilizing our PROBODY ® therapeutic platform and Moderna’s mRNA and lipid nanoparticle technologies.

The collaboration will leverage core scientific advances at Moderna and ours to open up the strategy of encoding potent, masked biologics through mRNA technologies, for the potential treatment of oncology and non-oncology conditions.

We and Moderna will collaborate on a specified number of preclinical research and discovery programs (“Moderna Collaboration Programs”) within a specified period under the Collaboration and License Agreement.

Under the Moderna Agreement, we granted Moderna an exclusive, worldwide, royalty-bearing license under certain of our intellectual property to develop, manufacture, commercialize and otherwise exploit certain products (“Moderna Licensed Products”) for all human and non-human diagnostic, prophylactic and therapeutic uses, subject to certain exceptions with respect to Licensed Products within certain Collaboration Programs.

Under the terms of the Moderna Agreement, Moderna made an upfront payment to us of $35.0 million, including $5.0 million of pre-paid research funding which was subsequently utilized by Moderna.

We may continue to receive research funding based on potential

aligned scopes of work between the two companies and we may be eligible to receive future development, regulatory and commercial milestone payments of up to $1.2 billion for all Moderna Licensed Products in total under the Moderna Agreement.

Moderna will pay us tiered royalties on global net sales of Moderna Licensed Products from high single digit to low-teen percentages, subject to certain reductions.

Moderna's royalty obligations continue with respect to each country and each Product until the later of (i) the date on which such Licensed Product is no longer covered by certain patent rights, (ii) the 10th anniversary of the first commercial sale of such product in such country, and (iii) the loss of regulatory exclusivity for such Moderna Licensed Product in such country.

In November 2025, we amended the Moderna Agreement to adjust some administrative obligations relating to certain intellectual property.

As of the first quarter of 2026, due to Moderna's budget considerations, the Moderna Collaboration Programs are paused.

Regeneron Pharmaceuticals, Inc.

The Company and Regeneron entered into a Collaboration and License Agreement (the “Regeneron Agreement”) in November 2022, to collaborate on the creation of conditionally activated investigational bispecific cancer therapies utilizing the Company’s PROBODY ® therapeutic platform and Regeneron’s Veloci-Bi ® bispecific antibody development platform.

The Company and Regeneron will collaborate on preclinical research and discovery activities for initially agreed upon collaboration programs (“Regeneron Collaboration Programs”) with an option to include additional Collaboration Programs (“Additional Collaboration Program Option”).

Under the Regeneron Agreement, the Company granted Regeneron an exclusive, worldwide, royalty-bearing license under certain Company intellectual property to develop, manufacture, commercialize and otherwise exploit licensed products (“Regeneron Licensed Products”) for all human and non-human diagnostic, prophylactic and therapeutic uses in oncology.

We and Regeneron entered into a Collaboration and License Agreement (the “Regeneron Agreement”) in November 2022, to collaborate on the creation of conditionally activated investigational bispecific cancer therapies utilizing our PROBODY ® therapeutic platform and Regeneron’s Veloci-Bi ® bispecific antibody development platform.

We and Regeneron will collaborate on preclinical research and discovery activities for initially agreed upon collaboration programs (“Regeneron Collaboration Programs”) with an option to include additional Collaboration Programs (“Additional Collaboration Program Option”).

Under the Regeneron Agreement, we granted Regeneron an exclusive, worldwide, royalty-bearing license under certain of our intellectual property to develop, manufacture, commercialize and otherwise exploit licensed products (“Regeneron Licensed Products”) for all human and non-human diagnostic, prophylactic and therapeutic uses in oncology.

Regeneron is responsible for funding the cost of preclinical research and discovery activities of both parties for all Regeneron Licensed Products and for funding the cost of development, manufacture and commercialization of all Regeneron Licensed Products worldwide.

Pursuant to the Regeneron Agreement, Regeneron made an upfront payment of $30.0 million to the Company.

Upon the achievement of certain development and regulatory milestones and commercial milestones, the Company is eligible to receive milestone payments of up to approximately $0.8 billion for the initial Regeneron Collaboration Programs.

In addition, the Company will receive research and development funding for the work related to the collaboration.

If Regeneron exercises its Additional Collaboration Program Options, the Company would be eligible to receive additional upfront payments, development and regulatory milestones payments, and commercial milestone payments of up to approximately $1.2 billion in aggregate for the additional Regeneron Collaboration Programs, which amount is exclusive of the $0.8 billion for the initial Regeneron Collaboration Programs.

The Company is also entitled to tiered royalties from high-single digit to low-teen percentage royalties from potential future sales, subject to certain reductions.

Pursuant to the Regeneron Agreement, Regeneron made an upfront payment of $30.0 million to us.

Upon the achievement of certain development and regulatory milestones and commercial milestones, we are eligible to receive milestone payments of up to approximately $0.8 billion for the initial Regeneron Collaboration Programs.

In addition, we will receive research and development funding for the work related to the collaboration.

If Regeneron exercises its Additional Collaboration Program Options, we would be eligible to receive additional upfront payments, development and regulatory milestones payments, and commercial milestone payments of up to approximately $1.2 billion in aggregate for the additional Regeneron Collaboration Programs, which amount is exclusive of the $0.8 billion for the initial Regeneron Collaboration Programs.

We are also entitled to tiered royalties from high-single digit to low-teen percentage royalties from potential future sales, subject to certain reductions.

Regeneron's royalty obligations continue with respect to each country and each Regeneron Licensed Product until the later of (i) the date on which such Regeneron Licensed Product is no longer covered by certain patent rights, (ii) the 10th anniversary of the first commercial sale of such product in such country, and (iii) the loss of regulatory exclusivity for such Regeneron Licensed Product in such country.

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To date, we have generally been able to successfully manufacture our investigational product candidates for our ongoing early-stage clinical trials with contract manufacturers.

However, the supply chain for the manufacturing of each of our product candidates is complicated and can involve many parties, including for CX-2051, CX-801, and CX-904.

However, the supply chain for the manufacturing of each of our product candidates is complicated and can involve many parties, including for Varseta-M and CX-801.

We do not own manufacturing facilities for producing such supplies and rely on third-party contract manufacturers to manufacture our clinical trial and preclinical study product supplies.

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Failure of any of these contractors could affect our ability to have clinical trial material available when needed and could result in substantial delay of our clinical trials.

For example, beginning in October 2023, one of our contract manufacturers for CX-2051 experienced production failures.

Although we are taking steps to manage our long-term supply of CX-2051, there can be no assurance that we will not have future production failures, which could affect our ability to conduct our trials for CX-2051 or any other clinical trial drug candidates, including CX-801 and CX-904, on our planned timeline or at all.

We do not have any long-term contracts and

we do not currently have readily available alternatives for many of our third-party contract manufacturers.

Although we are taking steps to manage our long-term supply of Varseta-M, there can be no assurance that we will not have production failures in the future, which could affect our ability to conduct our trials for Varseta-M or any other clinical trial drug candidates, including CX-801, on our planned timeline or at all.

We do not have any long-term contracts and we do not currently have readily available alternatives for many of our third-party contract manufacturers.

Consequently, there can be no assurance that our preclinical and clinical development product supplies will not be limited, interrupted, or of satisfactory quality or continue to be available at acceptable prices.

In particular, any replacement of any of our third-party contract manufacturers could require significant effort and expertise because there may be a limited number of qualified replacements.

In addition, we may encounter issues with transferring technology to a new third-party manufacturer, and we may encounter regulatory delays if we need to move the manufacturing of our products from one third-party manufacturer to another.

In addition, we may

encounter issues with transferring technology to a new third-party manufacturer, and we may encounter regulatory delays if we need to move the manufacturing of our products from one third-party manufacturer to another.

In order to conduct later-stage clinical trials of our product candidates, and eventually, if approved, commercial products, we will need to manufacture them in larger quantities.

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In August 2010, we entered into an agreement with UCSB, that grants us an exclusive license, with the right to sublicense, under the patent rights owned by UCSB covering mask and screening technologies relating to the identification and discovery of pro-protein biologics, including masks and substrates, for the identification of pro-proteins, for use in the fields of therapeutics, in vivo diagnostics, and prophylactics (the “UCSB Agreement”).

The UCSB Agreement also grants us an exclusive license, with the right to sublicense, under UCSB’s interest in certain patent rights we co-own with UCSB covering PROBODY antibodies and other pro-proteins in the fields of therapeutics, in vivo diagnostics and prophylactics.

The UCSB Agreement also grants us an exclusive license, with the right to sublicense, under UCSB’s interest in certain patent rights we co-own with UCSB covering certain conditionally activatable antibodies in the fields of therapeutics, in vivo diagnostics and prophylactics.

We are obligated to pay to UCSB royalties on net sales of licensed products in the low single-digit percentages, subject to annual minimum amounts as well as certain reductions.

We are required to make milestone payments to UCSB on the accomplishment of certain milestones totaling up to $1.1 million for each of the first two indications for each licensed product consisting of a molecule or compound covered by the licensed patent rights.

If the Company sublicenses its rights under the UCSB Agreement, it must pay UCSB a percentage of our total sublicense revenues ranging from the mid-single to mid-teen percentages, which total amount would be first reduced by the aggregate amount of certain research and development related expenses incurred by the Company and other permitted deductions.

If we sublicense our rights under the UCSB Agreement, we must pay UCSB a percentage of our total sublicense revenues ranging from the mid-single to mid-teen percentages, which total amount would be first reduced by the aggregate amount of certain research and development related expenses incurred by us and other permitted deductions.

License from ImmunoGen, Inc.

(acquired by AbbVie in 2024)

In January 2014, CytomX and ImmunoGen entered into the Research Collaboration Agreement (the “ImmunoGen Research Agreement”).

In January 2014, we entered into the Research Collaboration Agreement with ImmunoGen (the “ImmunoGen Research Agreement”).

The ImmunoGen Research Agreement provided us with the right to use ImmunoGen’s ADC technology for praluzatamab ravtansine (CX-2009) (the “CX-2009 License”).

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In 2025, CytomX terminated the CX-2009 License.

Under the agreement, ImmunoGen exercised an option to obtain a development and commercialization license for a target, EpCAM.

Under the ImmunoGen Research Agreement, ImmunoGen exercised its option to obtain a development and commercialization license for a target, EpCAM.

At the end of 2019, as a result of a strategic restructuring by ImmunoGen and its decision to out-license certain programs, we obtained a worldwide, exclusive, sublicensable license to the EpCAM conditionally activated ADC program from ImmunoGen (the “ImmunoGen 2019 License”).

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ImmunoGen is also entitled to royalties on product sales ranging from the mid-to-high single digits percentages.

In April 2024, the Company made a $5.0 million payment of the $35.0 million in potential clinical development milestone payments to AbbVie (formerly ImmunoGen) with respect to achieving the milestone of dosing the first patient for CX-2051 under the ImmunoGen 2019 License Agreement.

In April 2024, we made a $5.0 million payment of the $35.0 million in potential clinical development milestone payments to AbbVie (formerly ImmunoGen) with respect to achieving the milestone of dosing the first patient for Varseta-M under the ImmunoGen 2019 License Agreement.

CytomX is pioneering a new potential class of potent, anti-cancer biologic therapeutics – the PROBODY conditionally activated therapeutic platform.

The biotechnology and biopharmaceutical industries, including the ADC and immuno-oncology subsectors, are

characterized by rapid evolution of technologies, fierce competition and strong defense of intellectual property.

The biotechnology and biopharmaceutical industries, including the ADC and immuno-oncology subsectors, are characterized by rapid evolution of technologies, fierce competition and strong defense of intellectual property.

Any product candidates that we successfully develop and commercialize will have to compete with existing therapies and new therapies that may become available in the future.

While we believe that our proprietary PROBODY platform and scientific expertise in the field of biologics and immuno-oncology provide us with competitive advantages, a wide variety of institutions, including large biopharmaceutical companies, specialty biotechnology companies, academic research departments and public and private research institutions, are actively developing potentially competitive products and technologies.

We face substantial competition from biotechnology and biopharmaceutical companies developing biopharmaceutical products, particularly with respect to ADC, TCE and cytokine therapeutics, where competition is intense and rapidly evolving.

institutions, are actively developing potentially competitive products and technologies.

We face substantial competition from biotechnology and biopharmaceutical companies developing biopharmaceutical products, particularly with respect to ADC, TCE and immuno-oncology therapeutics, where competition is intense and rapidly evolving.

These competitors generally fall within the following categories:

Masking and conditional activation:

Several companies, including AbbVie, Adagene, Amgen, BioAtla, Halozyme Therapeutics, Vir Biotechnology, Merck, Roche, Takeda Pharmaceutical, Werewolf Therapeutics, Janux Therapeutics and Xilio Therapeutics are exploring, researching or developing antibody masking and/or conditional activation strategies, which could compete with our PROBODY platform.

Several companies, including AbbVie, Adagene, Amgen, BioAtla, Halozyme Therapeutics, Merck, Roche, Sanofi, Takeda Pharmaceutical, Werewolf Therapeutics, Janux Therapeutics, Xilio Therapeutics and Vir Biotechnology are exploring, researching or developing antibody masking and/or conditional activation strategies, which could compete with our PROBODY platform.

Antibody-drug conjugates:

Several large pharmaceutical companies, such as Lilly, AbbVie, Daiichi Sankyo, Gilead Sciences, Pfizer, Roche, Merck and Takeda Pharmaceutical are researching, developing, and in some cases, commercializing ADCs.

Several large pharmaceutical companies, such as AbbVie, Daiichi Sankyo, Gilead Sciences, Pfizer, Roche, Merck and Takeda Pharmaceutical are researching, developing, and in some cases, commercializing ADCs.

In addition, numerous smaller companies have ongoing efforts in the space.

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Cancer immunotherapy is one of the most competitive and fastest growing segments of the pharmaceutical industry.

Almost every large pharmaceutical company is developing or commercializing cancer immunotherapies, including Amgen, AstraZeneca, Bristol Myers Squibb, Celgene, GlaxoSmithKline, Merck, Novartis, Pfizer, Roche, and Sanofi.

Almost every large pharmaceutical company is developing or commercializing cancer immunotherapies, including Amgen, AstraZeneca, Bristol Myers Squibb, GlaxoSmithKline, Merck, Novartis, Pfizer, Roche, and Sanofi.

In addition, many large and mid-sized biotech companies such as BeiGene, Incyte, Nektar Therapeutics, and Alkermes have ongoing efforts in cancer immunotherapy.

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T-cell engaging therapies:

Several large pharmaceutics companies, such as Amgen, Novartis, and Roche, have on-going efforts in the field of T-cell engagers.

Several large pharmaceutical companies, such as Amgen, Novartis, and Roche, have on-going efforts in the field of T-cell engagers.

In addition, several mid-sized biotech companies such as MacroGenics and Xencor, as well as numerous smaller companies, including Janux Therapeutics, have ongoing efforts in TCEs.

Several companies have ongoing efforts or molecules in development in the field of cytokines including Bristol Myers Squibb, ImmunityBio, Jazz Pharmaceuticals, Merck, Nektar Therapeutics, Novartis, Sanofi, Werewolf Therapeutics, Xencor, and Xilio Therapeutics.

EpCAM-targeting Clinical Candidates:

With respect to Varseta-M (EpCAM-targeting Topo1 ADC product candidate), we are aware of other competing EpCAM targeting clinical stage therapeutics.

These include, but are not limited to T-cell engagers from BioNTech and BioAtla.

Colorectal Cancer Therapeutics:

In CRC, competition is increasing.

There are several approved therapies, and we also face competition from an increasing number of experimental therapies with different mechanisms of action, including chemotherapy, immunotherapy (e.g., PD-1, CTLA4, and PD-1/VEGF) and targeted therapies that are directed against CRC subtypes defined by biologic features including, but not limited to, KRAS mutational status, BRAF mutational status, microsatellite instability (“MSI”), and surface protein expression (e.g., cMET, CECAM5, HER2, EGFR) being studied by AbbVie, Janssen, Merck KGaA, Pfizer, Exelixis, Revolution Medicines, Summit Therapeutics, Agenus, Adagene, Cardiff Oncology and Harbour Biomed, among others.

Multiple competitor experimental therapies are further along in development than Varseta-M, including several in Phase 3 development.

These novel competitor agents, alone or in combination with other anti-cancer agents, may potentially impact the approval of or adoption of therapeutics for the treatment of CRC.

CX-801 and Melanoma Competition:

The landscape in melanoma is highly competitive and includes major pharmaceutical companies as well as biotechnology companies.

Treatments for melanoma have improved over the last two decades with the introduction of checkpoint inhibitors including the approved drugs such as Keytruda ® , Opdivo ® , and Yervoy ® which have become widely used therapies in early line treatment settings for melanoma.

Development programs such as CX-801 are often studied in advanced metastatic melanoma where it may be challenging to demonstrate clinical benefit in patients refractory to checkpoint inhibitors and combinations with approved therapies are often required.

Additionally, there are competing programs in melanoma across a range of modalities including other cytokines, cell therapies, oncolytic viruses, and T-cell engagers from companies such as Replimune, Immunocore and Immatics.

Many of our competitors, either alone or with strategic partners, have substantially greater financial, technical and human resources than we do.

Accordingly, our competitors may be more successful than us in obtaining approval for treatments and achieving widespread market acceptance, rendering our treatments obsolete or non-competitive.

Accelerated merger and acquisition activity in the biotechnology and biopharmaceutical industries may result in even more resources being concentrated among a smaller number of our competitors.

These companies also compete with us in recruiting and retaining qualified scientific and management personnel, establishing clinical study sites and patient registration for clinical studies and acquiring technologies complementary to, or necessary for, our programs.

Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies.

Our commercial opportunity could be substantially limited in the event that our competitors develop and commercialize products that are more effective, safer, less toxic, more convenient or less expensive than our comparable products.

In geographies that are critical to our commercial success, competitors may also obtain regulatory approvals before us, resulting in our competitors building a strong market position in advance of our products’ entry.

We believe the factors determining the success of our programs will be the efficacy, safety and convenience of our product candidates.

Accordingly, our competitors may be more successful than us in progressing clinical development, obtaining approval for treatments and achieving widespread market acceptance, rendering our treatments obsolete or non-competitive.

Intellectual Property

We strive to protect and enhance the proprietary technology, inventions, and improvements that are commercially important to our business, including seeking, maintaining, and defending patent rights, whether developed internally or licensed from third parties.

Our policy is to seek to protect our proprietary position by, among other methods, pursuing and obtaining patent protection in the United States and in jurisdictions outside of the United States related to our proprietary technology, inventions, improvements, platforms and product candidates that are important to the development and implementation of our business.

policy is to seek to protect our proprietary position by, among other methods, pursuing and obtaining patent protection in the United States and in jurisdictions outside of the United States related to our proprietary technology, inventions, improvements, platforms and product candidates that are important to the development and implementation of our business.

Our patent portfolio is intended to cover, but is not limited to, our technology platforms, our product candidates and components thereof, their methods of use and processes for their manufacture, our proprietary reagents and assays, and any other inventions that are commercially important to our business.

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We expect to rely on data exclusivity, market exclusivity, patent term adjustment and patent term extensions when available.

Our commercial success may depend in part on our ability to

obtain and maintain patent and other proprietary protection for our technology, inventions, and improvements;

Our commercial success may depend in part on our ability to obtain and maintain patent and other proprietary protection for our technology, inventions, and improvements;

to preserve the confidentiality of our trade secrets;

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As of January 2026, our patent portfolio contains at least 245 granted patents (some of which are co-owned with a third party) and at least 300 pending patent applications (some of which are co-owned with a third party).

We have exclusively licensed UCSB’s interest in the co-owned patent family covering PROBODY technology in the fields of therapeutics, in vivo diagnostics and prophylactics.

We have exclusively licensed UCSB’s interest in the co-owned patent family covering certain conditionally activatable antibodies in the fields of therapeutics, in vivo diagnostics and prophylactics.

These patents and patent applications include claims directed to our PROBODY platform technology, including PROBODY drug conjugates, bispecific and other multi-specific PROBODY therapeutics (including T-cell engaging bispecific PROBODY therapeutics), protease cleavable linkers, and cancer immunotherapy PROBODY therapeutics.

In addition, we have exclusively licensed a patent portfolio of patent families from UCSB patents and patent applications that cover compositions and methods related to screening for and identification of masks and protease-cleavable linkers that we have incorporated into our PROBODY therapeutics and may incorporate into future PROBODY therapeutics.

In addition, we have exclusively licensed a portfolio of patent families from UCSB that cover compositions and methods related to screening for and identification of masks and protease-cleavable linkers that we have used to design some PROBODY therapeutics and may use to design future PROBODY therapeutics.

As for the PROBODY platform, product candidates and processes we develop and commercialize, in the normal course of business, we intend to pursue, where appropriate, patent protection or trade secret protection relating to compositions, methods of manufacture, assay methods, methods of use, treatment of indications, dosing and formulations.

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Further, we are prepared to file patent applications, as we consider appropriate under the circumstances, relating to the new technologies that we develop.

In addition to filing and prosecuting patent applications in the United States, we often file counterpart patent applications in the European Union and in additional countries where we believe such foreign filing is likely to be beneficial.

In addition to filing and prosecuting patent applications in the United States, we often file counterpart patent applications in European countries and in additional countries where we believe such foreign filing is likely to be beneficial.

Our currently issued patents will likely expire on dates ranging from 2028 to 2042, unless we receive patent term extension or adjustment as might be available under applicable law.

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In the case of employees, the agreements provide that all inventions conceived by the individual, and which are related to our current or planned business or research and development or made during normal working hours, on our premises or using our equipment or proprietary information, are our exclusive property.

In many cases our confidentiality and other agreements with consultants, outside scientific collaborators, sponsored researchers and other advisors require them to assign or grant us licenses to inventions they invent as a result of the work or services they render under such agreements or grant us an option to negotiate a license to use such inventions.

In many cases our confidentiality and other agreements with consultants, outside scientific collaborators, sponsored researchers and other

advisors require them to assign or grant us licenses to inventions they invent as a result of the work or services they render under such agreements or grant us an option to negotiate a license to use such inventions.

Government Regulation and Product Approval

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Each protocol, and any subsequent material amendment to the protocol, must be submitted to the FDA as part of the IND.

While the IND is active, progress reports summarizing the results of the clinical trials and nonclinical studies performed since the last progress report, among other information, must be submitted at least annually to the FDA, and written IND safety reports must be submitted to the FDA and investigators for serious and unexpected suspected adverse events, findings from other studies suggesting a significant risk to humans exposed to the same or similar drugs, findings from animal or in vitro testing suggesting a significant risk to humans, and any clinically important increased incidence of a serious suspected adverse reaction compared to that listed in the protocol or investigator brochure.

annually to the FDA, and written IND safety reports must be submitted to the FDA and investigators for serious and unexpected suspected adverse events, findings from other studies suggesting a significant risk to humans exposed to the same or similar drugs, findings from animal or in vitro testing suggesting a significant risk to humans, and any clinically important increased incidence of a serious suspected adverse reaction compared to that listed in the protocol or investigator brochure.

Furthermore, an independent IRB for each site proposing to conduct each clinical trial must review and approve the plan for any clinical trial and its informed consent form before the clinical trial begins at that site and must monitor the study until completion.

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Within 60 days following submission of the application, the FDA reviews a BLA to determine if it is substantially complete before the agency accepts it for filing.

The FDA may refuse to file any BLA that it deems incomplete or not properly reviewable at the time of

submission and may request additional information.

The FDA may refuse to file any BLA that it deems incomplete or not properly reviewable at the time of submission and may request additional information.

In this event, the BLA must be resubmitted with the additional information.

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The two primary types of FDA marketing authorization applicable to a medical device are premarket notification, also called 510(k) clearance, and premarket approval (“PMA”).

If use of companion diagnostic is essential to safe and effective use of a biologic product, then the FDA generally will require approval or clearance of the diagnostic contemporaneously with the approval of the biologic product.

According to FDA guidance, for

novel product candidates such as drugs and therapeutic biologics, a companion diagnostic device and its corresponding product candidate should be approved or cleared contemporaneously by FDA for the use indicated in the product labeling.

If use of a companion diagnostic is essential to safe and effective use of a biologic product, then the FDA generally will require approval or clearance of the diagnostic contemporaneously with the approval of the biologic product.

According to FDA guidance, for novel product candidates such as drugs and therapeutic biologics, a companion diagnostic device and its corresponding product candidate should be approved or cleared contemporaneously by FDA for the use indicated in the product labeling.

The guidance also explains that a companion diagnostic device used to make treatment decisions in clinical trials of a product candidate generally will be considered an investigational device unless it is employed for an intended use for which the device is already approved or cleared.

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In particular, for a diagnostic, the applicant must demonstrate that the diagnostic produces reproducible results when the same sample is tested multiple times by multiple users at multiple laboratories.

In addition, as part of the PMA review, the FDA will typically inspect the manufacturer’s facilities for compliance with the Quality System Regulation (“QSR”) which currently represents FDA’s GMP requirements for medical devices, and imposes elaborate testing, control, documentation and other quality assurance requirements.

In addition, as part of the PMA review, the FDA will typically inspect the manufacturer’s facilities for compliance with the Quality Management System Regulation (“QMSR”) which represents FDA’s GMP requirements for medical devices, and imposes elaborate testing, control, documentation and other quality assurance requirements.

PMA approval is not guaranteed, and the FDA may ultimately respond to a PMA submission with a not approvable determination based on deficiencies in the application and require additional clinical trial or other data that may be expensive and time-consuming to generate and that can substantially delay approval.

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Device manufacturers must also establish registration and device listings with the FDA.

A medical device manufacturer’s manufacturing processes and those of its suppliers are required to comply with the applicable portions of the QSR, which cover the methods and documentation of the design, testing, production, processes, controls, quality assurance, labeling, packaging and shipping of medical devices.

A medical device manufacturer’s manufacturing processes and those of its suppliers are required to comply with the applicable portions of the QMSR, which cover the methods and documentation of the design, testing, production, processes, controls, quality assurance, labeling, packaging and shipping of medical devices.

Domestic facility records and manufacturing processes are subject to periodic unscheduled inspections by the FDA.

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The sponsor of a Fast Track product candidate has opportunities for frequent interactions with the review team during product development and, once a BLA is submitted, the application may be eligible for Priority Review.

BLA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the BLA.

A BLA for a Fast Track product candidate may also be eligible for Rolling Review, where the FDA may consider for review sections of the BLA on a rolling basis before the complete application is submitted, if the sponsor provides a schedule for the submission of the sections of the BLA, the FDA agrees to accept sections of the BLA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the BLA.

A product candidate intended to treat a serious or life-threatening disease or condition may also be eligible for Breakthrough Therapy designation to expedite its development and review.

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After a BLA is submitted for a product candidate, including a product candidate with a Fast Track designation and/or Breakthrough Therapy designation, the BLA may be eligible for other types of FDA programs intended to expedite the FDA review and approval process, such as Priority Review.

A BLA is eligible for Priority Review if the product candidate has the potential to provide a significant improvement in the treatment, diagnosis or prevention of a serious disease or condition compared available products.

Priority review designation means the FDA’s goal is to take action on the marketing application within six months of the 60-day filing date, compared to ten months under standard review.

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Orphan Drug Designation does not convey any advantage in or shorten the duration of the regulatory review and approval process.

If a product candidate that has Orphan Drug Designation subsequently receives the first FDA approval for the disease or condition for which it has such designation, the product candidate is entitled to orphan product exclusivity, which means that the FDA may not approve any other applications to market the same product candidate for the same disease or condition for seven years, except under limited circumstances, such as a showing of clinical superiority to the product with orphan drug exclusivity or if the FDA finds that the holder of the orphan drug exclusivity has not shown that it can assure the availability of sufficient quantities of the orphan drug to meet the needs of patients with the disease or condition for which the drug was designated.

Orphan drug exclusivity does not prevent the FDA from approving a different drug for the same disease or condition, or the same drug for a different disease or condition.

If a product candidate that has Orphan Drug Designation subsequently receives the first FDA approval for the disease or condition for which it has such designation, the product candidate is entitled to orphan product exclusivity, which means that the FDA may not approve any other applications to market the same product for the same approved indication or use within such rare disease or condition for seven years, except under limited circumstances, such as a showing of clinical superiority to the product with orphan drug exclusivity in the relevant indication or use, or if the FDA finds that the holder of the orphan drug exclusivity has not shown that it can assure the availability of sufficient quantities of the orphan drug to meet the needs relating to the approved indication or use of patients with the disease or condition for which the drug was designated.

Orphan drug exclusivity does not prevent the FDA from approving a different drug for the same indication or use within the relevant disease or condition, or the same drug for any indication or use within a different disease or condition.

Among the other benefits of orphan drug designation are tax credits for certain research and a waiver of the BLA application user fee.

A designated orphan drug may not receive orphan drug exclusivity if it is approved for a use that is broader than the indication for which it received orphan designation.

In addition, orphan drug exclusive marketing rights in the United States may be lost if the FDA later determines that the request for designation was materially defective or, as noted above, if a second applicant demonstrates that its product is clinically superior to the approved product with orphan exclusivity or the manufacturer of the approved product is unable to assure sufficient quantities of the product to meet the needs of patients with the rare disease or condition

In addition, orphan drug exclusive marketing rights in the United States may be lost if the FDA later determines that the request for designation was materially defective or, as noted above, if a second applicant demonstrates that its product is clinically superior to the approved product with orphan exclusivity within the relevant indication or use or if the manufacturer of the approved product is unable to assure sufficient quantities of the product to meet the needs relating to the approved indication or use of patients with the applicable rare disease or condition.

Pediatric Studies

The Pediatric Research Equity Act (“PREA”) requires a sponsor to conduct pediatric studies for most therapeutic candidates and biologics, for a new active ingredient, new indication, new dosage form, new dosing regimen or new route of administration.

Under PREA, original BLAs and supplements thereto must contain a pediatric assessment unless the sponsor has received a deferral or waiver.

PREA, original BLAs and supplements thereto must contain a pediatric assessment unless the sponsor has received a deferral or waiver.

The required assessment must assess the safety and effectiveness of the product candidate for the claimed indications in all relevant pediatric subpopulations and support dosing and administration for each pediatric subpopulation for which the product candidate is determined to be safe, pure and potent.

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Once a BLA approval is granted, the FDA may withdraw the approval if compliance with regulatory requirements is not maintained or if problems occur after the biologic product reaches the market.

Later discovery of previously unknown problems with a product

candidate may result in restrictions on the product candidate or even complete withdrawal of the product candidate from the market.

Later discovery of previously unknown problems with a product candidate may result in restrictions on the product candidate or even complete withdrawal of the product candidate from the market.

After approval, some types of changes to the approved product, such as adding new indications, manufacturing changes and additional labeling claims, are subject to further FDA review and approval.

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The FDA does not regulate the behavior of physicians in their choice of treatments.

The FDA does, however, restrict manufacturer’s communications on the subject of off-label use of their products.

The FDA does, however, restrict manufacturer’s communications on the subject of off-label use of their

However, companies may share truthful and not misleading information that is otherwise consistent with a product’s FDA-approved labelling.

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The ACA expanded coverage for the uninsured while at the same time containing overall healthcare costs.

With regard to biopharmaceutical products, the ACA, among other things, addressed a new methodology by which rebates owed by manufacturers under the Medicaid Drug Rebate Program are calculated for drugs that are inhaled, infused, instilled, implanted or injected, increased the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program and extended the rebate program to individuals enrolled in Medicaid managed care organizations, and established annual fees and taxes on manufacturers of certain branded prescription drugs.

inhaled, infused, instilled, implanted or injected, increased the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program and extended the rebate program to individuals enrolled in Medicaid managed care organizations, and established annual fees and taxes on manufacturers of certain branded prescription drugs.

Since its enactment, there have been judicial, executive and Congressional challenges to certain aspects of the ACA.

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On August 2, 2011, the Budget Control Act of 2011 among other things, created measures for spending reductions by Congress, which led to aggregate reductions to Medicare payments to providers, starting in April 2013, and due to subsequent legislative amendments, will stay in effect through 2032, with the exception of a temporary suspension from May 1, 2020 through March 31, 2022, unless additional Congressional action is taken.

On January 2, 2013, the American Taxpayer Relief Act of 2012 (the “ATRA”) was signed into law which, among other things, also reduced Medicare payments to several types of providers, including hospitals, imaging centers and cancer treatment centers, and increased the statute of limitations

period for the government to recover overpayments to providers from three to five years.

In addition, in March 2021, the American Rescue Plan Act of 2021 was signed into law, which eliminated the statutory Medicaid drug rebate cap, which was previously set at 100% of a drug’s average manufacturer price, beginning January 1, 2024.

In addition, in March 2021, the American Rescue Plan Act of 2021 was signed into law, which eliminated the statutory cap on drug manufactures' Medicaid drug rebate liability, which was previously set at 100% of a drug’s average manufacturer price, beginning January 1, 2024.

Recently, there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products, which has resulted in several Congressional inquiries and proposed bills designed to, among other things, bring more transparency to product pricing, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for drug products.

Most recently, on August 16, 2022, the Inflation Reduction Act of 2022, or IRA, was signed into law.

Among other things, the IRA requires manufacturers of certain drugs to engage in price negotiations with Medicare (beginning in 2026), imposes rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation (first due in 2023), and replaces the Part D coverage gap discount program with a new discounting program (which began in 2025).

On August 16, 2022, the Inflation Reduction Act of 2022, or IRA, was signed into law.

Among other things, the IRA requires manufacturers of certain drugs to engage in price negotiations with Medicare, imposes rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation (first due in 2023), and replaces the Part D coverage gap discount program with a new discounting program (which began in 2025).

The IRA permits the Secretary of the Department of Health and Human Services (HHS) to implement many of these provisions through guidance, as opposed to regulation, for the initial years.

The Centers for Medicare & Medicaid Services, or CMS, has published the negotiated prices for the initial ten drugs, which will first be effective in 2026, and has published the list of the subsequent 15 drugs that will be subject to negotiation, although the drug price negotiation program is currently subject to legal challenges.

The Centers for Medicare & Medicaid Services, or CMS, has published the negotiated prices for the initial ten drugs, which went into effect in 2026 and the subsequent 15 drugs, which will first be effective in 2027, as well as the next set of 15 drugs that will be subject to negotiation, although the drug price negotiation program is currently subject to legal challenges.

For that and other reasons, it is currently unclear how the IRA will be effectuated.

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We cannot predict the extent of the impact of any changes to any of these laws on us.

Finally, in some foreign countries, the proposed pricing for a product candidate must be approved before it may be lawfully marketed.

The requirements governing therapeutic pricing vary widely from country to country.

For example, the European Union provides options for its member states to restrict the range of medicinal products for which their national health insurance systems provide reimbursement and to control the prices of medicinal products for human use.

A member state may approve a specific price for the medicinal product, or it may instead adopt a system of direct or indirect controls on the profitability of the company placing the medicinal product on the market.

There can be no assurance that any country that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our product candidates.

Historically, therapeutic candidates launched in the European Union do not follow price structures of the U.S.

and generally tend to be significantly lower.

The One Big Beautiful Bill Act, which was enacted in July 2025, imposes significant reductions in the funding of the Medicaid program.

Such reductions are expected to decrease the number of persons enrolled in Medicaid and reduce the services covered by Medicaid, which could adversely affect our sales of any product candidate that we commercialize.

The Trump administration is pursuing a two-fold strategy to reduce drug costs in the U.S.

While it is unclear whether and how the Trump proposals will be implemented, the Trump policies may have a negative impact on the pharmaceutical industry and on our ability to receive adequate revenues for any product candidate that we commercialize.

On the one hand, President Trump has indicated to impose significant tariffs on pharmaceutical manufacturers that do not adopt pricing policies such as most favored nation pricing, which would tie the price for drugs in the U.S.

to the lowest price in a group of other countries.

In response, multiple manufacturers have reportedly entered into confidential pricing agreements with the federal government.

On the other hand, the Trump administration is pursuing traditional regulatory pathways to impose drug pricing policies, and published two proposed regulations in December 2025, referred to as Globe and Guard.

If finalized, these regulations would implement mandatory payment models under which manufacturers of eligible drugs would be required to pay rebates to the federal government on a portion of the units of their drugs that are reimbursed by Medicare, with the rebate amount based on most favored nation pricing.

While the impact of the Globe and Guard proposed regulations, if finalized, cannot yet be determined, it is likely to be significant.

Even regulatory proposals or executive actions that are ultimately deemed unlawful could negatively impact the U.S.

pharmaceutical sector and our business.

Individual states in the United States have also become increasingly active in passing legislation and implementing regulations designed to control pharmaceutical product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access, marketing cost disclosure, drug price reporting and other transparency measures.

Some states have enacted legislation creating prescription drug affordability boards, which ultimately may attempt to impose price limits on certain drugs in these states, and at least one state board is imposing an upper payment limit.

Some states are also seeking to implement general, across the board price caps for pharmaceuticals, or are seeking to regulate drug distribution.

Some measures are designed to encourage importation from other countries.

These types of initiatives may result in additional reductions in Medicare, Medicaid, and other healthcare funding, and may otherwise affect the prices we may obtain for our investigational products that receive approval.

Adoption of other new legislation or regulation at the federal, state, or foreign level could further limit reimbursement for pharmaceuticals, including our product candidates if approved.

Other Healthcare Laws

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Our Company Origins and Team

Our PROBODY platform technology has its origins in work performed at the University of California, Santa Barbara (“UCSB”), by our scientific founder Professor Patrick Daugherty.

Since our inception, we have continued developing and adding to this technology and aspire to design a pipeline of PROBODY therapeutics that will better the lives of cancer patients.

Our technology has its origins in work performed at the University of California, Santa Barbara (“UCSB”), by our scientific founder Professor Patrick Daugherty.

Since our inception, we have continued to make advances to this technology, while also creating other technology, and aspire to design a pipeline of PROBODY therapeutics that will better the lives of cancer patients.

We have assembled an experienced and talented group of individuals dedicated to the advancement of cancer care.

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Sean McCarthy, leads a team that draws on robust experience in all phases of product discovery, clinical development and commercialization.

Our management team members have significant experience in oncology with previous experience at Amylin Pharmaceuticals, Catalyst Biosciences, Coherus BioSciences, Elan Phramaceuticals, Eli Lilly and Company, Exelixis, Genentech, Millennium, Novartis, Onyx Pharmaceuticals, Portola Pharmaceuticals, SGX, Xencor and other companies.

Our management team members have significant experience in oncology with previous experience at Amylin Pharmaceuticals, Catalyst Biosciences, Coherus BioSciences, Elan Pharmaceuticals, Eli Lilly and Company, Exelixis, Genentech, Harpoon, Millennium, Novartis, Onyx Pharmaceuticals, Portola Pharmaceuticals, Replicate, SGX and other companies.

Human Capital

As of December 31, 2024, we had 119 full-time employees and 2 part-time employees.

As of December 31, 2025, we had 69 full-time employees.

Of these employees, 50 were primarily engaged in research and development activities.

In January 2025, we announced a restructuring which will result in a reduction to the workforce by approximately 40% and is expected to be substantially completed in the first quarter of 2025.

None of our employees are represented by a labor union or covered by collective bargaining agreements and we consider our employee relations to be good.

Our human capital resources objectives include, as applicable, identifying, recruiting, retaining, incentivizing and integrating our existing

and additional employees.

Our human capital resources objectives include, as applicable, identifying, recruiting, retaining, incentivizing and integrating our existing and additional employees.

The principal purposes of our equity incentive plans are to attract, retain and motivate selected employees, consultants and directors through the granting of stock-based compensation awards and cash-based performance bonus awards.

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We view our operations and measure our business as one reportable segment operating in the United States.

See Note 2 and Note 16 to our audited financial statement included elsewhere in this Annual Report on Form 10-K for additional information.

See Note 2 and Note 16 to our audited financial statements included elsewhere in this Annual Report on Form 10-K for additional information.

Additional information required by this item is incorporated herein by reference to PART II.

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Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 1. Business