What changed in this filing

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Item 2. Management’s Discussion and Analysis

2025-11-13 compared with 2025-08-14 · 99 added, 88 removed, 261 unchanged (42% of the section changed)

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To date, we have presented data across our clinical-stage programs showing clinical validation for our tumor-activation platform.

Our most advanced clinical-stage product candidates are vilastobart, an Fc-enhanced, tumor-activated, anti-CTLA-4 monoclonal antibody, or mAb, and XTX301, a tumor-activated, engineered interleukin 12, or IL-12, therapy.

We are currently advancing clinical development for vilastobart in combination with atezolizumab (Tecentriq®) in a Phase 2 clinical trial in patients with metastatic microsatellite stable colorectal cancer, or metastatic MSS CRC, under a co-funded clinical trial collaboration with F.

Our most advanced clinical-stage product candidates are vilastobart, a tumor-activated, Fc-enhanced anti-CTLA-4 monoclonal antibody, or mAb, and efarindodekin alfa (XTX301), a tumor-activated, engineered interleukin 12, or IL-12, therapy.

We are currently advancing clinical development for vilastobart in combination with atezolizumab (Tecentriq®) in a Phase 2 clinical trial in patients with microsatellite stable metastatic colorectal cancer, or MSS mCRC, under a co-funded clinical trial collaboration with F.

Hoffmann-La Roche Ltd, or Roche.

In May 2025, we announced updated data from the ongoing Phase 2 clinical trial at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, demonstrating additional anti-tumor activity, further duration of responses and a generally well-tolerated safety profile and we anticipate reporting additional data from the Phase 2 trial in the first half of 2026.

For XTX301, we have completed enrollment in Phase 1A monotherapy dose escalation and evaluation of those patients is ongoing, and we continue to enroll patients in Phase 1B monotherapy dose expansion of our ongoing Phase 1 clinical trial in patients with advanced solid tumors under our exclusive license agreement with Gilead Sciences, Inc., or Gilead.

In addition to our clinical-stage product candidates, we are leveraging our proprietary tumor-activation platform to advance multiple preclinical programs for XTX501, a masked PD-1/IL-2 bispecific and masked T cell engager molecules, including wholly owned programs targeting the tumor-associated antigens for PSMA, CLDN18.2 and STEAP1 and an additional program under our collaboration, license and option agreement with AbbVie Group Holdings Limited, or AbbVie.

In November 2025, we announced new data from the ongoing Phase 2 clinical trial at the Society for Immunotherapy of Cancer (SITC) 40 th Annual Meeting in patients with MSS mCRC without liver metastases and high plasma tumor mutational burden, or TMB, and we anticipate reporting additional data from the Phase 2 trial in the first half of 2026.

Based on the promising clinical activity and safety profile demonstrated by vilastobart to date as a combination therapy, including in patients who had high plasma TMB, we are actively seeking a partner to develop vilastobart in combination with PD-(L)1 or PD1-VEGF in MSS mCRC and other tumor types.

For efarindodekin alfa, in the third quarter of 2025, we initiated a Phase 2 trial in patients with advanced solid tumors and achieved a $17.5 million development milestone under our exclusive license agreement with Gilead Sciences, Inc., or Gilead.

We have completed enrollment in the Phase 1A monotherapy dose escalation and Phase 1B monotherapy dose expansion portions of our ongoing Phase 1/2 clinical trial, and evaluation of patients is ongoing.

In addition to our clinical-stage product candidates, we are leveraging our proprietary tumor-activation platform to advance multiple preclinical programs for XTX501, a bispecific PD-1/masked IL-2 and our masked T cell engager molecules, including wholly owned programs targeting the tumor-associated antigens for PSMA, CLDN18.2 and STEAP1 and an additional program under our collaboration, license and option agreement with AbbVie Group Holdings Limited, or AbbVie.

Liquidity and Going Concern Overview

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In June 2025, we closed a follow-on public offering of prefunded warrants and accompanying common stock warrants and received net proceeds of $47.0 million after deducting underwriting discounts and commissions and offering expenses payable by us.

In connection with the offering, we issued prefunded warrants to purchase 66,676,000 shares of common stock, accompanied by Series A warrants to purchase 66,676,000 shares of common stock (or, in certain circumstances, prefunded warrants), Series B warrants to purchase 66,676,000 shares of common stock (or, in certain circumstances, prefunded warrants) and Series C warrants to purchase 66,676,000 shares of common stock (or, in certain circumstances, prefunded warrants).

If the Series B warrants and Series C warrants are exercised in cash at their initial exercise price of $0.75 per warrant, we will receive up to $100.0 million of additional gross proceeds by the second half of 2026.

In connection

with the offering, we issued prefunded warrants to purchase 66,676,000 shares of common stock, accompanied by Series A warrants to purchase 66,676,000 shares of common stock (or, in certain circumstances, prefunded warrants), Series B warrants to purchase 66,676,000 shares of common stock (or, in certain circumstances, prefunded warrants) and Series C warrants to purchase 66,676,000 shares of common stock (or, in certain circumstances, prefunded warrants).

If all of the Series B warrants and Series C warrants are exercised in cash at their initial exercise price of $0.75 per warrant, we will receive up to $100.0 million of additional gross proceeds by the second half of 2026.

For more information, refer to Note 8 to our condensed consolidated financial statements included elsewhere in this Quarterly Report on Form 10-Q.

Since inception, we have incurred significant operating losses, including net losses of $29.1 million and $31.1 million for the six months ended June 30, 2025 and 2024, respectively, and a net loss of $58.2 million for the year ended December 31, 2024.

As of June 30, 2025, we had an accumulated deficit of $412.9 million.

Since inception, we have incurred significant operating losses, including net losses of $45.4 million and $45.1 million for the nine months ended September 30, 2025 and 2024, respectively, and a net loss of $58.2 million for the year ended December 31, 2024.

As of September 30, 2025, we had an accumulated deficit of $429.1 million.

We expect to continue to incur significant expenses and operating losses for the foreseeable future, particularly to the extent we:

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As a result, we will need substantial additional capital to support our continuing operations and pursue our strategy.

As of June 30, 2025, we had cash and cash equivalents of $121.6 million.

Based on our current operating plans, we anticipate that our existing cash and cash equivalents as of June 30, 2025 will be sufficient to enable us to fund our operating expenses and capital expenditure requirements through the end of the third quarter of 2026.

As of September 30, 2025, we had cash and cash equivalents of $103.8 million.

In the fourth quarter of 2025, we received a $17.5 million development milestone under our license agreement with Gilead.

Based on our current operating plans, we anticipate that our existing cash and cash equivalents as of September 30, 2025, together with the $17.5 million development milestone received under our license agreement with Gilead, will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the first quarter of 2027.

However, we have based our estimates on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we anticipate.

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These conditions raise substantial doubt about our ability to continue as a going concern.

In order to fund our operations, we will need to raise additional capital, which could be obtained through the cash exercise, if any, of the Series B warrants and Series C warrants issued in connection with our June 2025 follow-on public offering, the receipt of milestone payments, option-related fees or other contingent payments under our existing agreements with Gilead and AbbVie, additional public or private equity offerings, debt financings, additional collaborations, partnerships or licensing

arrangements or other sources.

In order to fund our operations, we will need to raise additional capital, which could be obtained through the cash exercise of the Series B warrants and Series C warrants issued in connection with our June 2025 follow-on public offering, the receipt of milestone payments, option-related fees or other contingent payments under our existing agreements with Gilead and AbbVie, additional public or private equity offerings, debt financings, additional collaborations, partnerships or licensing arrangements or other sources.

However, there can be no assurance that we will receive additional proceeds from the exercise of the common stock warrants or from contingent payments under our existing agreements with Gilead or AbbVie or that we will be able to complete any such transaction on acceptable terms or otherwise.

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A significant portion of our research and development costs have been, and will continue to be, external costs.

We track these external costs, such as fees paid to CDMOs, CROs, preclinical study vendors and other third parties in connection with our manufacturing and manufacturing process development, clinical trials, preclinical studies and other research activities by program.

We track these external costs, such as fees paid to CDMOs, CROs,

preclinical study vendors and other third parties in connection with our manufacturing and manufacturing process development, clinical trials, preclinical studies and other research activities by program.

Due to the number of ongoing programs and our ability to use resources across several projects, personnel-related expenses and indirect or shared operating costs incurred for our research and development programs are not recorded or maintained on a program-by-program basis.

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Change in Fair Value of Common Stock Warrant Liabilities

The change in fair value of common stock warrant liabilities consists of the change in the fair value of the common stock warrant liabilities from the issuance date of June 5, 2025 to June 30, 2025.

The change in fair value of common stock warrant liabilities consists of the change in the fair value of the common stock warrant liabilities from the issuance date of June 5, 2025 to September 30, 2025.

Other Income (Expense), Net

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Results of Operations

Comparison of the three months ended June 30, 2025 and 2024

The following table summarizes our results of operations for the three months ended June 30, 2025 and 2024 (in thousands):

Comparison of the three months ended September 30, 2025 and 2024

The following table summarizes our results of operations for the three months ended September 30, 2025 and 2024 (in thousands):

Three Months Ended

September 30,

Collaboration and license revenue

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Collaboration and License Revenue

Collaboration and license revenue increased by $5.7 million from $2.4 million for the three months ended June 30, 2024 to $8.1 million for the three months ended June 30, 2025.

Collaboration and license revenue increased by $16.8 million from $2.3 million for the three months ended September 30, 2024 to $19.1 million for the three months ended September 30, 2025.

The increase was due to collaboration and license revenue recognized under the collaboration, license and option agreement and stock purchase agreement that we entered into in February 2025 with AbbVie and an increase in collaboration and license revenue recognized under the license agreement and stock purchase agreement with Gilead, which included a cumulative catch-up of collaboration and license revenue of $7.0 million related to the adjustment of the overall transaction price due to the achievement of the $17.5 million development milestone during the third quarter of 2025.

Research and Development Expenses

The following table summarizes our research and development expenses for the three months ended June 30, 2025 and 2024 (in thousands):

The following table summarizes our research and development expenses for the three months ended September 30, 2025 and 2024 (in thousands):

Three Months Ended

September 30,

efarindodekin alfa (XTX301)

Other early programs and indirect research and development

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Total research and development expenses

Research and development expenses increased by $4.1 million from $11.2 million for the three months ended June 30, 2024 to $15.3 million for the three months ended June 30, 2025.

Research and development expenses increased by $3.6 million from $10.8 million for the three months ended September 30, 2024 to $14.3 million for the three months ended September 30, 2025.

The changes in research and development expenses were primarily due to the following:

● vilastobart costs increased by $1.8 million, primarily driven by a $2.5 million increase in clinical development activities related to our ongoing Phase 1/2 clinical trial evaluating vilastobart in combination with atezolizumab;

in addition, for the three months ended June 30, 2024, research and development expenses included a $1.0 million development milestone under our CTLA-4 monoclonal antibody license agreement with WuXi Biologics (Hong Kong) Limited, or WuXi Biologics, for which there was no comparable cost during the three months ended June 30, 2025;

● XTX501 costs for the three months ended June 30, 2025 consisted of manufacturing activities related to IND-enabling studies and pre-clinical development activities;

for the three months ended June 30, 2024, XTX501 costs were not separately tracked as we had not begun performing IND-enabling studies;

● XTX202 costs decreased by $1.5 million, primarily driven by a decrease in clinical development activities as a result of discontinuing further investment in XTX202;

• vilastobart costs decreased by $3.7 million, primarily driven by $3.5 million in aggregate development milestones

that we incurred during the three months ended September 30, 2024 under our CTLA-4 monoclonal antibody

license agreement with WuXi Biologics (Hong Kong) Limited, or WuXi Biologics, and our amended and restated

exclusive license agreement with City of Hope, for which there was no comparable cost during the three months ended September 30, 2025;

• efarindodekin alfa costs increased by $1.0 million, primarily driven by a $0.8 million increase in clinical development

activities related to initiation of our Phase 2 clinical trial evaluating efarindodekin alfa as a monotherapy in patients with certain advanced solid tumors and a $0.2 million increase in manufacturing activities;

• XTX501 costs for the three months ended September 30, 2025 consisted of manufacturing activities related to IND-enabling studies and pre-clinical development activities;

for the three months ended September 30, 2024, XTX501 costs were not separately tracked as we had not begun performing IND-enabling studies;

• XTX202 costs for the three months ended September 30, 2025 consisted of investigator costs invoiced during the final winddown process of the discontinued XTX202 study;

and XTX202 costs for the three months ended September 30, 2024 include the effect of invoiced investigator costs being lower than previously estimated amounts;

• other early programs and indirect research and development costs increased by $1.4 million, primarily driven by an increase in external expenses related to preclinical research and development activities;

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General and Administrative Expenses

The following table summarizes our general and administrative expenses for the three months ended June 30, 2025 and 2024 (in thousands):

The following table summarizes our general and administrative expenses for the three months ended September 30, 2025 and 2024 (in thousands):

Three Months Ended

September 30,

Personnel-related

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Total general and administrative expenses

General and administrative expenses increased by $1.3 million from $5.8 million for the three months ended June 30, 2024 to $7.1 million for the three months ended June 30, 2025.

General and administrative expenses increased by $0.4 million from $6.3 million for the three months ended September 30, 2024 to $6.7 million for the three months ended September 30, 2025.

The changes in general and administrative expenses were primarily due to the following:

● personnel-related costs increased by $0.5 million, primarily driven by a $0.5 million increase in salaries, bonuses and benefits due to higher general and administrative headcount and a $0.1 million increase in recruiting and other personnel-related costs, partially offset by a $0.1 million decrease in stock-based compensation;

• personnel-related costs decreased by $0.3 million, primarily driven by a $0.4 million decrease in stock-based compensation and a $0.2 million decrease in recruiting and other personnel-related costs, partially offset by a $0.3 million increase in salaries, bonuses and benefits due to higher general and administrative headcount;

• professional and consulting fees increased by $0.7 million, primarily driven by an increase in legal fees and other professional costs;

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Restructuring

We did not recognize any restructuring expenses for the three months ended June 30, 2025.

We recognized $0.1 million in restructuring expenses for the three months ended June 30, 2024, consisting of employee outplacement service costs related to the workforce reduction announced in March 2024.

We did not recognize any restructuring expenses for the three months ended September 30, 2025.

We recognized a credit of $41,000 in restructuring expenses for the three months ended September 30, 2024 related to a change in estimate for costs of continuation of certain employee benefits related to the workforce reduction announced in March 2024.

Change in Fair Value of Common Stock Warrant Liabilities

The change in fair value of common stock warrant liabilities for the three months ended June 30, 2025 was due to a loss of less than $0.1 million on the change in the fair value of the common stock warrant liabilities between the issuance date of June 5, 2025 and the quarter ended June 30, 2025.

The change in fair value of common stock warrant liabilities for the three months ended September 30, 2025 was due to a loss of $15.4 million due to the increase in the fair value of the common stock warrant liabilities between June 30, 2025 and September 30, 2025, which was primarily driven by an increase in the price per share of our common stock.

Other Income (Expense), Net

Other income (expense), net, of $1.4 million for the three months ended June 30, 2025 included $2.3 million of the issuance costs we incurred in connection with the sale and issuance of the prefunded warrants and common stock warrants in June 2025 in connection with our follow-on public offering, which were allocated to the common stock warrant liabilities and were partially offset by $0.9 million of interest income.

Other income (expense), net of $0.8 million for the three months ended June 30, 2024 consisted of interest income.

Comparison of the six months ended June 30, 2025 and 2024

The following table summarizes our results of operations for the six months ended June 30, 2025 and 2024 (in thousands):

Six Months Ended

Other income (expense), net, increased by $0.3 million from $0.7 million for the three months ended September 30, 2024 to $1.0 million for the three months ended September 30, 2025.

The increase in other income (expense), net was primarily due to an increase in interest income due to a higher average cash balance.

Comparison of the nine months ended September 30, 2025 and 2024

The following table summarizes our results of operations for the nine months ended September 30, 2025 and 2024 (in thousands):

Nine Months Ended

September 30,

Collaboration and license revenue

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Collaboration and License Revenue

Collaboration and license revenue increased by $8.7 million from $2.4 million for the six months ended June 30, 2024 to $11.0 million for the six months ended June 30, 2025.

The increase was due to an increase in collaboration and license revenue recognized under the license agreement and stock purchase agreement with Gilead and collaboration and license revenue recognized under the collaboration, license and option agreement and stock purchase agreement that we entered into in February 2025 with AbbVie.

Collaboration and license revenue increased by $25.5 million from $4.6 million for the nine months ended September 30, 2024 to $30.1 million for the nine months ended September 30, 2025.

Research and Development Expenses

The following table summarizes our research and development expenses for the six months ended June 30, 2025 and 2024 (in thousands):

Six Months Ended

The following table summarizes our research and development expenses for the nine months ended September 30, 2025 and 2024 (in thousands):

Nine Months Ended

September 30,

efarindodekin alfa (XTX301)

Other early programs and indirect research and development

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Total research and development expenses

Research and development expenses increased by $2.0 million from $21.6 million for the six months ended June 30, 2024 to $23.6 million for the six months ended June 30, 2025.

Research and development expenses increased by $5.5 million from $32.4 million for the nine months ended September 30, 2024 to $37.9 million for the nine months ended September 30, 2025.

The changes in research and development expenses were primarily due to the following:

● vilastobart costs, which include $2.0 million of cost-sharing payments earned under our Roche clinical collaboration during each of the six months ended June 30, 2025 and 2024, that were recorded as a reduction in research and development expenses, increased by $2.1 million, primarily driven by an increase in clinical

development activities related to our ongoing Phase 1/2 clinical trial evaluating vilastobart in combination with atezolizumab;

in addition, for the six months ended June 30, 2024, research and development expenses included a $1.0 million development milestone under our CTLA-4 monoclonal antibody license agreement with WuXi Biologics, for which there was no comparable cost during the six months ended June 30, 2025;

● XTX301 costs decreased by $0.3 million, primarily driven by a $0.1 million decrease in clinical development activities related to our ongoing Phase 1 clinical trial and a $0.1 million decrease in manufacturing activities;

● XTX501 costs for the six months ended June 30, 2025 consisted of manufacturing activities related to IND-enabling studies and pre-clinical development activities;

for the six months ended June 30, 2024, XTX501 costs were not separately tracked as we had not begun performing IND-enabling studies;

• vilastobart costs decreased by $1.6 million, primarily driven by $4.5 million in aggregate development milestones that we incurred during the nine months ended September 30, 2024 under our CTLA-4 monoclonal antibody license agreement with WuXi Biologics and our amended and restated exclusive license agreement with City of Hope, for which there was no comparable costs during the nine months ended September 30, 2025, partially offset by a $2.8 million increase in clinical development activities related to our ongoing Phase 1/2 clinical trial evaluating vilastobart in combination with atezolizumab;

• efarindodekin alfa costs increased by $0.7 million, primarily driven by an increase in clinical development activities related to our ongoing Phase 1/2 clinical trial evaluating efarindodekin alfa as a monotherapy in patients with certain advanced solid tumors;

• XTX501 costs for the nine months ended September 30, 2025 consisted of manufacturing activities related to IND-enabling studies and pre-clinical development activities;

for the nine months ended September 30, 2024, XTX501 costs were not separately tracked as we had not begun performing IND-enabling studies;

• XTX202 costs decreased by $3.3 million, primarily driven by a decrease in clinical development activities as a result of discontinuing further investment in XTX202;

• other early programs and indirect research and development costs increased by $3.1 million, primarily driven by an increase in external expenses related to preclinical research and development activities;

● personnel-related costs increased by $0.9 million, primarily driven by a $1.0 million increase in salaries, bonuses and benefits due to higher general and administrative headcount and a $0.1 million increase in recruiting and other personnel-related costs, partially offset by a $0.2 million decrease in stock-based compensation.

• personnel-related costs increased by $2.3 million, primarily driven by a $2.4 million increase in salaries, bonuses and benefits due to higher research and development headcount and a $0.1 million increase in recruiting and other personnel-related costs, partially offset by a $0.2 million decrease in stock-based compensation.

General and Administrative Expenses

The following table summarizes our general and administrative expenses for the six months ended June 30, 2025 and 2024 (in thousands):

Six Months Ended

The following table summarizes our general and administrative expenses for the nine months ended September 30, 2025 and 2024 (in thousands):

Nine Months Ended

September 30,

Personnel-related

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Total general and administrative expenses

General and administrative expenses increased by $3.7 million from $12.0 million for the six months ended June 30, 2024 to $15.6 million for the six months ended June 30, 2025.

General and administrative expenses increased by $4.0 million from $18.3 million for the nine months ended September 30, 2024 to $22.3 million for the nine months ended September 30, 2025.

The changes in general and administrative expenses were primarily due to the following:

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Restructuring

We did not recognize any restructuring expenses for the six months ended June 30, 2025.

We recognized $1.0 million in restructuring expenses for the six months ended June 30, 2024.

The restructuring expenses were associated with the

workforce reduction announced in March 2024 and consisted of employee severance, benefits continuation and outplacement service costs.

We did not recognize any restructuring expenses for the nine months ended September 30, 2025.

We recognized $0.9 million in restructuring expenses for the nine months ended September 30, 2024.

The restructuring expenses were associated with the workforce reduction announced in March 2024 and consisted of employee severance, benefits continuation and outplacement service costs.

Change in Fair Value of Common Stock Warrant Liabilities

The change in fair value of common stock warrant liabilities for the six months ended June 30, 2025 was due to a loss of less than $0.1 million on the change in the fair value of the common stock warrant liabilities between the issuance date of June 5, 2025 and the quarter ended June 30, 2025.

The change in fair value of common stock warrant liabilities for the nine months ended September 30, 2025 was due to a loss of $15.4 million due to an increase in the fair value of the common stock warrant liabilities between the issuance date of June 5, 2025 and September 30, 2025, which was primarily driven by an increase in the price per share of our common stock.

Other Income (Expense), Net

Other income (expense), net of $0.8 million for the six months ended June 30, 2025 included $2.3 million of the issuance costs we incurred in connection with the sale and issuance of the prefunded warrants and common stock warrants in June 2025 in connection with our follow-on public offering, which were allocated to the common stock warrant liabilities and were partially offset by $1.4 million of interest income.

Other income (expense), net of $1.1 million for the six months ended June 30, 2024 consisted of interest income.

Other income (expense), net of $0.2 million for the nine months ended September 30, 2025 included $2.3 million of the issuance costs we incurred in connection with the sale and issuance of the prefunded warrants and common stock warrants in June 2025 in connection with our follow-on public offering, which were allocated to the common stock warrant liabilities and were partially offset by $2.5 million of interest income.

Other income (expense), net of $1.8 million for the nine months ended September 30, 2024 consisted of interest income.

Liquidity and Capital Resources

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sales of common stock in our IPO and through at-the-market offerings;

the sale of prefunded warrants and common stock warrants in a follow-on public offering;

the sale of prefunded warrants and common stock warrants in a follow-on public

and upfront payments under our collaboration and license agreements with AbbVie and Gilead.

Through June 30, 2025, we have received an aggregate of $531.8 million in gross proceeds from such transactions, including $224.5 million in gross proceeds from the sale and issuance of preferred units and convertible preferred stock, $129.9 million in gross proceeds from our IPO, $72.0 million in upfront cash payments under our collaboration and license agreements with AbbVie and Gilead, $46.3 million in gross proceeds from the sale and issuance of common stock and prefunded warrants in private placements with certain existing accredited investors, Gilead and AbbVie, $9.1 million in gross proceeds from the sale and issuance of common stock through at-the-market offerings and $50.0 million in gross proceeds from the sale of prefunded warrants and common stock warrants through a follow-on public offering.

As of June 30, 2025, we had cash and cash equivalents of $121.6 million.

In November 2022, we filed a universal shelf registration statement on Form S-3 with the SEC to register for sale up to $250.0 million of our common stock, preferred stock, debt securities, units and warrants, which we could issue and sell from time to time in one or more offerings, which became effective on November 18, 2022 (333-268264), or the Prior S-3 Shelf.

In November 2022, we entered into a sales agreement, or the Cowen Sales Agreement, with Cowen and Company LLC under which we could issue and sell shares of our common stock, from time to time, having an aggregate offering price of up to $75.0 million under a sales agreement prospectus filed as part of the Prior S-3 Shelf.

During the year ended December 31, 2024, we issued and sold 7,000,000 shares of our common stock pursuant to the Cowen Sales Agreement at a price of $1.00 per share for aggregate gross proceeds of $7.0 million.

During the three months ended March 31, 2025, we issued and sold an additional 1,550,000 shares of our common stock pursuant to the Cowen Sales Agreement at a weighted average price of $1.3348 per share for aggregate gross proceeds of approximately $2.1 million.

In March 2025, we filed a universal shelf registration statement on Form S-3 with the SEC to register for sale up to $250.0 million of our common stock, preferred stock, debt securities, units and warrants, which we may issue and sell from time to time in one or more offerings, which became effective on May 8, 2025 (333-285703), or the New S-3 Shelf.

In March 2025, we terminated the Cowen Sales Agreement and we entered into a new sales agreement with Leerink Partners, LLC, or the Leerink Sales Agreement, under which we may issue and sell shares of our common stock from time to time at an aggregate offering price of up to $50.0 million.

Prior to the effectiveness of the New S-3 Shelf, the offering of shares under the Leerink Sales Agreement was registered under the Prior S-3 Shelf.

In connection with the effectiveness of the New S-3

Shelf, the registration of such offering under the Prior S-3 Shelf was terminated and such offering was registered under the New S-3 Shelf.

Through September 30, 2025, we have received an aggregate of $531.8 million in gross proceeds from such transactions, including $224.5 million in gross proceeds from the sale and issuance of preferred units and convertible preferred stock, $129.9 million in gross proceeds from our IPO, $72.0 million in upfront cash payments under our collaboration and license agreements with AbbVie and Gilead, $46.3 million in gross proceeds from the sale and issuance of common stock and prefunded warrants in private placements with certain existing accredited investors, Gilead and AbbVie, $9.1 million in gross proceeds from the sale and issuance of common stock through at-the-market offerings and $50.0 million in gross proceeds from the sale of prefunded warrants and common stock warrants through a follow-on public offering.

As of September 30, 2025, we had cash and cash equivalents of $103.8 million.

In the fourth quarter of 2025, we received a $17.5 million development milestone under our license agreement with Gilead.

In March 2025, we entered into a sales agreement with Leerink Partners, LLC, under which we may issue and sell shares of our common stock from time to time at an aggregate offering price of up to $50.0 million.

Please see Note 8 to our condensed consolidated financial statements appearing elsewhere in our Quarterly Report on Form 10-Q for additional information about our at-the-market offering program.

The following table provides information regarding our cash flows for each period presented (in thousands):

Six Months Ended

Nine Months Ended

September 30,

Net cash provided by (used in):

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The cash used in operating activities resulted primarily from our net losses adjusted for non-cash charges, which are generally due to stock-based compensation, depreciation and amortization, as well as changes in components of operating assets and liabilities, which are generally due to increased expenses and timing of vendor payments.

During the six months ended June 30, 2025, net cash provided by operating activities of $14.5 million was primarily driven by net changes in operating assets and liabilities of $37.5 million, which includes the $49.1 million recorded as deferred revenue in connection with our collaboration, license and option agreement and stock purchase agreement with AbbVie, and net non-cash expenses of $6.1 million, partially offset by our net loss of $29.1 million.

During the six months ended June 30, 2024, net cash provided by operating activities of $9.5 million was primarily driven by the $39.1 million received from Gilead for the upfront payment under the license agreement and equity investments under the stock purchase agreement, which were recorded as deferred revenue at the outset of the arrangement and net non-cash expenses of $4.2 million, partially offset by our net loss of $31.1 million and remaining changes in operating assets and liabilities of $2.8 million.

During the nine months ended September 30, 2025, net cash used in operating activities of $3.0 million was primarily driven by net changes in operating assets and liabilities of $19.5 million, which includes the $49.1 million received from AbbVie under the collaboration, license and option agreement and stock purchase agreement that was recorded as deferred revenue at the outset of the arrangement, and net non-cash expenses of $22.9 million, which includes the $15.4 million loss recorded on the change in fair value of our common stock warrant liabilities, partially offset by our net loss of $45.4 million.

During the nine months ended September 30, 2024, net cash used in operating activities of $4.2 million was primarily driven by our net loss of $45.1 million, partially offset by changes in operating assets and liabilities of $34.8 million, which includes the $39.1 million received from Gilead under the license agreement and stock purchase agreement that was recorded as deferred revenue at the outset of the arrangement, and net non-cash expenses of $6.2 million.

Investing Activities

During the six months ended June 30, 2025 and 2024, net cash used in investing activities consisted of purchases of property and equipment.

During the nine months ended September 30, 2025 and 2024, net cash used in investing activities consisted of purchases of property and equipment.

Financing Activities

During the six months ended June 30, 2025, net cash provided by financing activities of $52.1 million consisted of proceeds from the sale of prefunded warrants and common stock warrants through a follow-on public offering, proceeds from the sale and issuance of common stock to AbbVie in a private placement and proceeds from the sale and issuance of common stock through ATM offerings.

During the six months ended June 30, 2024, net cash provided by financing activities of $21.0 million consisted of proceeds from the sale and issuance of common stock and prefunded warrants in private placements with certain existing accredited investors and Gilead and proceeds from the sale and issuance of common stock under our at-the-market offering program, partially offset by repayments of debt principal under our loan agreement with PacWest and payments on our finance lease for certain lab equipment.

During the nine months ended September 30, 2025, net cash provided by financing activities of $51.9 million consisted of proceeds from the sale of prefunded warrants and common stock warrants through a follow-on public offering, proceeds from the sale and issuance of common stock to AbbVie in a private placement and proceeds from the sale and issuance of common stock through ATM offerings.

During the nine months ended September 30, 2024, net cash provided by financing activities of $21.0 million consisted of proceeds from the sale and issuance of common stock and prefunded warrants in private placements with certain existing accredited investors and Gilead and proceeds from the sale and issuance of common stock under our at-the-market offering program, partially offset by repayments of debt principal under our loan agreement with PacWest and payments on our finance lease for certain lab equipment.

Capital Requirements and Going Concern

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Additionally, the biotechnology industry is subject to a competitive wage environment that may also increase our operating costs in the future.

As of June 30, 2025, we had cash and cash equivalents of $121.6 million.

As of September 30, 2025, we had cash and cash equivalents of $103.8 million.

However, we have based our estimates on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we anticipate.

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These conditions raise substantial doubt about our ability to continue as a going concern.

However, there can be no assurance that we will receive additional proceeds from the exercise of the common stock warrants or from contingent payments under our existing agreements with Gilead or AbbVie or that the we will be able to complete any such transaction on acceptable terms or otherwise.

If we are not able to secure sufficient additional capital when needed, we may need to implement additional cost reduction strategies, which could include delaying, limiting, further reducing or eliminating both internal and external costs related to our operations and research and development programs.

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For more information regarding the terms of the warrants we issued in our June 2025 follow-on public offering, refer to Note 8 to our condensed consolidated financial statements included elsewhere in this Quarterly Report on Form 10-Q.

The accompanying condensed consolidated financial statements included elsewhere in this Quarterly Report on Form 10-Q have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business for the foreseeable future.

business for the foreseeable future.

The condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty.

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Our future capital requirements, both short-term and long-term, will depend on many factors, including, but not limited to:

● the scope, progress, results and costs of research and development for our current and future product candidates, including our current and planned clinical trials for our clinical-stage product candidates, vilastobart and XTX301, and ongoing preclinical development for our current and future product candidates;

• the scope, progress, results and costs of research and development for our current and future product candidates, including our current and planned clinical trials for our clinical-stage product candidates, vilastobart and efarindodekin alfa, and ongoing preclinical development for our current and future product candidates;

• our ability to maintain our collaboration and license agreements with AbbVie and Gilead;

● the timing and amount of milestones, option-related fees and other contingent payments under our collaboration, license and option agreement with AbbVie for tumor-activated immunotherapies and our license agreement with Gilead for XTX301, as well as the scope, costs and timing of our development obligations under these agreements;

• the timing and amount of milestones, option-related fees and other contingent payments under our collaboration, license and option agreement with AbbVie for tumor-activated immunotherapies and our license agreement with Gilead for efarindodekin alfa, as well as the scope, costs and timing of our development obligations under these agreements;

• our ability to maintain our co-funded clinical trial collaboration with Roche to further develop vilastobart in combination with atezolizumab, including the timing and amount of cost-sharing payments under the collaboration;

● the potential receipt of up to $100.0 million in additional gross proceeds from the exercise, if any, of the common stock warrants issued in connection with our June 2025 follow-on public offering;

• the potential receipt of up to $100.0 million in additional gross proceeds, if all of the Series B and Series C common stock warrants issued in connection with our June 2025 follow-on public offering are exercised;

• our ability to secure sufficient additional capital or implement other strategies needed to alleviate the substantial doubt about our ability to continue as a going concern;

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Our expectation with respect to our ability to fund our currently planned operations is based on estimates that are subject to various risks and uncertainties.

Our operating plan may change as a result of many factors currently unknown to

management and there can be no assurance that our current operating plan will be achieved in the time frame anticipated by us, and we may exhaust our available capital resources sooner than we expect.

Our operating plan may change as a result of many factors currently unknown to management and there can be no assurance that our current operating plan will be achieved in the time frame anticipated by us, and we may exhaust our available capital resources sooner than we expect.

Adequate additional capital may not be available to us on acceptable terms, or at all.

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Contractual Obligations

During the six months ended June 30, 2025, there have been no material changes to our contractual obligations as reported in our Annual Report on Form 10-K for the year ended December 31, 2024.

During the nine months ended September 30, 2025, there have been no material changes to our contractual obligations as reported in our Annual Report on Form 10-K for the year ended December 31, 2024.

Critical Accounting Policies and Use of Estimates

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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-Q

Item 2. Management’s Discussion and Analysis