What changed in this filing

/stocks — the workspaceLOADING

Item 1. Business

2022-02-24 compared with 2021-02-24 · 328 added, 291 removed, 370 unchanged (63% of the section changed)

We are a clinical-stage biopharmaceutical company focused on discovering and developing engineered monoclonal antibody and cytokine therapeutics to treat patients with cancer and autoimmune diseases who have unmet medical needs.

We are advancing a broad portfolio of clinical-stage drug candidates from our proprietary XmAb® technology platforms.

We use our protein engineering capabilities to increase our understanding of protein structure and interactions and to design new XmAb technologies and development candidates with improved properties.

In contrast to conventional approaches to antibody design, which focus on the segment of antibodies that interact with target antigens, our work is focused on the Fc domain, the part of an antibody that interacts with multiple segments of the immune system and controls antibody structure.

The Fc domain is constant and interchangeable among antibodies, and our engineered Fc domains, the XmAb technology, can be readily substituted for natural Fc domains.

Our protein engineering capabilities and XmAb technologies enable us and our partners to develop antibodies and biotherapeutic drug candidates with improved properties and function, which can provide innovative approaches to treating disease and potential clinical advantage over other treatment options.

For example, our capabilities have enabled us to develop an antibody scaffold to rapidly create novel bispecific antibodies that bind two different targets simultaneously, creating entirely new biological mechanisms.

Other applications of our XmAb technologies enhance antibody performance by increasing immune inhibitory activity, improving cytotoxicity, extending circulating half-life and stabilizing novel protein structures, such as engineered cytokines.

Currently, there are two marketed drugs that have been developed with our XmAb technologies.

On July 31, 2020, the U.S.

Food and Drug Administration (FDA) approved our partner MorphoSys’ Monjuvi® (tafasitamab-cxix) in combination with lenalidomide, for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) not otherwise specified, including DLBCL arising from low grade lymphoma, and who are not eligible for autologous stem cell transplant (ASCT).

This indication is approved under accelerated approval based on overall response rate.

Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).

We created and initially developed tafasitamab, which incorporates our XmAb Cytotoxic Fc Domain to enhance its tumor killing properties.

Monjuvi is a registered trademark of MorphoSys AG.

Alexion's Ultomiris® (ravulizumab-cwvz) was first approved by the FDA in December 2018.

It is now approved in the U.S., Europe and Japan for the treatment of adult patients with paroxysmal nocturnal hemoglobinuria (PNH) and for the treatment of patients with atypical hemolytic uremic syndrome (aHUS).

Alexion used our Xtend™ Fc Domain to enhance the half-life of Ultomiris to allow for a longer duration of action, less frequent dosing and reduced patient burden of therapy compared to the previous generation therapy, Soliris®.

We are advancing a broad portfolio of clinical-stage XmAb® drug candidates from our proprietary protein engineering technology platforms.

We also use our protein engineering capabilities to increase our understanding of protein structure and interactions and to design new technologies and XmAb development candidates with improved properties.

In addition to engineering protein-target interactions, our approach to protein design includes engineering Fc domains, the part of an antibody that interacts with multiple segments of the immune system and controls antibody structure.

The Fc domain is constant and interchangeable among antibodies, and our engineered XmAb Fc domains can be readily substituted for natural Fc domains.

Our protein engineering capabilities and Fc technologies enable us and our partners to develop XmAb antibodies and biotherapeutic drug candidates with improved properties and functionality, which can provide innovative approaches to treating disease and potential clinical advantage over other treatment options.

For example, we have developed an antibody scaffold to rapidly create novel bispecific antibodies that bind two different targets simultaneously, creating entirely new biological mechanisms.

Other applications of our protein engineering technologies enhance antibody performance by increasing immune inhibitory activity, improving cytotoxicity, extending circulating half-life and stabilizing novel protein structures, such as engineered cytokines.

Three marketed XmAb medicines have been developed with our protein engineering technologies and are generating royalties for us.

Our protein engineering capabilities allow us to continually explore new functionality in the Fc region, which provides us with opportunities to:

5 unchanged sentences

Advance the clinical development of our XmAb bispecific antibody and cytokine drug candidates.

Our modular XmAb bispecific technology and protein engineering capabilities enable us to rapidly advance multiple drug candidates into clinical development.

We and our partners are enrolling Phase 1 studies for seven of these candidates to treat patients with many different types of cancer, and an eighth, to be developed for patients with autoimmune disease, is expected to start a Phase 1 study in early 2021.

Our modular bispecific technology and protein engineering capabilities enable us to rapidly advance multiple drug candidates into clinical development.

We and our partners are enrolling patients in multiple mid-stage and early-stage clinical studies to evaluate our XmAb bispecific antibody drug candidates and engineered cytokine drug candidates.

We and our partners plan to advance additional bispecific antibodies and cytokines into clinical development in the future.

Build a large and diversified portfolio of XmAb drug candidates.

We create new XmAb-engineered antibody and cytokine product candidates to exploit the novel mechanisms of action enabled by our XmAb technology platforms and advance them into our internal portfolio of preclinical and clinical-stage assets, or, if strategically appropriate, we license certain drug candidates to leading pharmaceutical and biotechnology companies.

Leverage our protein engineering capabilities, XmAb technologies, and XmAb drug candidates with partnerships, collaborations, and licenses to generate revenue streams, create new drug candidates and combination treatments, and identify new indications for our pipeline of drug candidates.

Build and manage a large and diversified portfolio of XmAb drug candidates.

We create new XmAb bispecific antibody and cytokine product candidates to exploit the novel mechanisms of action enabled by our protein engineering technology platforms, and we advance them into our portfolio of preclinical and clinical-stage assets.

We regularly evaluate our portfolio of candidates and make additional investments in those candidates that present promising early clinical and scientific data, partner certain drug candidates to third-party biotechnology and pharmaceutical companies, and will stop development of candidates based on the evaluation of emerging clinical and scientific data and the competitive environment for such programs.

Leverage our protein engineering capabilities, XmAb Fc domains, and XmAb drug candidates with partnerships, collaborations, and licenses to generate revenue streams, create new drug candidates and combination treatments, and identify new indications for our pipeline of drug candidates.

Generate revenue streams.

The plug-and-play nature of our XmAb technologies and our ability to generate multiple drug candidates efficiently provides us opportunities to generate revenue from licensing and collaboration arrangements.

The plug-and-play nature of our Fc technologies and our ability to generate multiple drug candidates efficiently provides us opportunities to generate revenue from licensing and collaboration arrangements.

In 2021, we received total proceeds of $204.9 million in upfront payments, milestone payments and royalties from such arrangements.

Create new drug candidates and investigate novel combination therapies .

We seek to leverage our XmAb technologies and drug candidates with partners to create novel drug candidates, including combination therapies.

In 2020, we entered into separate agreements with Atreca, Inc.

and The University of Texas MD Anderson Cancer Center to create novel CD3 bispecific antibody drug candidates.

We also entered into a clinical collaboration with MorphoSys AG and Incyte Corporation, in which we plan to conduct multiple clinical studies in B-cell lymphomas, combining our plamotamab drug candidate with tafasitamab in combination with lenalidomide.

Create new XmAb drug candidates and investigate novel combination therapies .

We seek to leverage our XmAb Fc domains and protein engineering capabilities with partners to create novel XmAb drug candidates, and to evaluate our XmAb drug candidates in combination with other therapeutic agents, when applicable.

Identify new indications for our pipeline of drug candidates.

In August 2020, we entered into a five-year strategic collaboration with MD Anderson.

We will support Investigator Sponsored Trials (ISTs) in which MD Anderson's investigators may explore additional indications for our pipeline of candidates.

Broaden the functionality of our XmAb technology platform.

We are conducting further research into the function and application of antibody Fc domains in order to expand the scope of our XmAb technology platforms.

We use the modularity of our XmAb bispecific Fc technology to build bispecific antibodies and cytokines in a variety of formats, recently introducing CD3 bispecific antibodies of a mixed valency format, the XmAb 2+1 bispecific antibody.

XmAb 2+1 bispecific antibodies may preferentially kill tumor cells with high target expression which may be especially beneficial in designing antibodies that target solid tumors .

We continue to support Investigator Sponsored Trials (ISTs) in which investigators may explore additional therapeutic indications with XmAb drug candidates.

Broaden the functionality of our XmAb Fc technology platforms.

We are conducting further research into the function and application of antibody Fc domains in order to expand the scope of our XmAb Fc technology platforms.

We use the modularity of our XmAb bispecific Fc domains to engineer bispecific antibodies and cytokines in a variety of structural formats.

For example, CD3 bispecific antibodies of a mixed valency format, i.e., the XmAb 2+1 bispecific antibody, may preferentially kill tumor cells that have higher target expression than normal cells, which may be especially beneficial in designing antibodies that target solid tumors .

Additionally, we have engineered CD28 bispecific antibodies to provide conditional CD28 co-stimulation of T cells, activating them when bound to tumor cells.

Targeted CD28 bispecific antibodies may provide conditional co-stimulation of T cells, for example, to T cells recognizing neoantigens or in concert with CD3 T-cell engaging bispecific antibodies.

Continue to expand our patent portfolio protecting our XmAb technologies and XmAb candidates.

We seek to expand our intellectual property estate and protect our XmAb technologies, our development programs, and product candidates by filing and prosecuting patents in the United States and other countries.

Where appropriate we will seek expansion and extension of patents issued for our product candidates.

XmAb Bispecific Technologies

A distinguishing feature of our XmAb technologies arises from our modular approach to protein engineering.

This provides us with flexibility to seek out new applications of the XmAb Bispecific Fc Domain and enables us to design new bispecific antibody and cytokine drug candidates with distinct and novel mechanisms-of-action.

This approach is illustrated through the expansion of our portfolio of novel bispecific antibody and cytokine candidates.

Our business, research, and clinical efforts are to develop and advance our XmAb bispecific technologies and our portfolio of bispecific antibodies and cytokines in oncology and autoimmune diseases.

Continue to expand our patent portfolio protecting our Fc technologies and XmAb drug candidates.

We seek to expand our intellectual property estate and protect our proprietary Fc technologies, our development programs, and XmAb drug candidates by filing and prosecuting patents in the United States and other countries.

Where appropriate, we will seek expansion and extension of patents issued for our product candidates and for partnered product candidates that incorporate one of our Fc technologies.

XmAb Bispecific Fc Domain and New Multi-Specific Antibody Formats

Our modular approach to protein engineering is a distinguishing feature of our Fc technologies.

This inherent flexibility enables us to design new XmAb bispecific antibody and cytokine drug candidates with distinct and novel mechanisms-of-action and to seek out new applications of the XmAb Bispecific Fc Domain.

Our business, research, and clinical efforts are to develop and advance our Fc technologies and our portfolio of XmAb bispecific antibody and engineered cytokine drug candidates in oncology and autoimmune diseases.

CD3 candidates:

our initial bispecific antibody candidates are designed to redirect T cells to tumor cells through the engagement of an antigen on tumor cells and CD3, an activating receptor on T cells.

We are currently conducting Phase 1 studies for three CD3 bispecific antibody candidates:

plamotamab, vibecotamab, and tidutamab.

We have expanded our T-cell redirecting CD3 class of bispecific antibodies to create the XmAb 2+1 bispecific antibody format, utilizing two identical tumor targeting domains and one CD3 targeting domain.

The affinities for antigen binding are reduced, which allows for selective engagement and killing of high antigen-expressing tumor cells over low antigen-expressing normal cells.

CD3 bispecific antibody candidates are designed to redirect T cells to tumor cells through the engagement of an antigen on tumor cells and CD3, an activating receptor on T cells.

We are currently advancing two CD3 bispecific antibody candidates in Phase 2 clinical development:

plamotamab and tidutamab.

We have significantly expanded the potential of our CD3 bispecific antibodies with the multi-specific XmAb 2+1 bispecific antibody format, utilizing two identical tumor targeting domains and one CD3 targeting domain.

The affinities for antigen binding are engineered to enable selective engagement and killing of high antigen-expressing tumor cells over low antigen-expressing normal cells.

In preclinical models, XmAb 2+1 bispecific antibodies bound preferentially to tumor cells compared to normal cells and effectively recruited T cells to kill tumor cells selectively.

We believe that these properties will be particularly important when developing bispecific antibodies against many solid tumor targets, which can have poor tolerability because such targets are often expressed on a range of normal tissues, including critical organs.

Our initial candidate using the XmAb 2+1 format is XmAb819, an ENPP3 x CD3 bispecific antibody, and we expect to submit an Investigational New Drug (IND) application in 2021.

believe that these properties will be particularly important when developing bispecific antibodies against many solid tumor targets, where standard monovalent targeting of tumor antigens could lead to poor tolerability because such targets are often expressed on a range of normal tissues, including critical organs.

We are currently initiating a Phase 1 study for XmAb819, an ENPP3 x CD3 bispecific antibody, which is engineered with the XmAb 2+1 bispecific antibody format.

CD28 candidates:

3 unchanged sentences

Targeted CD28 bispecific antibodies may provide conditional co-stimulation of T cells, for example, to T cells recognizing neoantigens or in concert with CD3 T-cell engaging bispecific antibodies.

We have engineered XmAb bispecific antibodies to provide conditional CD28 co-stimulation of T cells, activating them when bound to tumor cells, and we are conducting preclinical studies of internal CD28 candidates.

Under our collaboration with Janssen Biotech, Inc., we are applying our XmAb bispecific Fc technology to create and characterize CD28 bispecific antibody candidates against a prostate tumor target.

We have engineered XmAb bispecific antibodies to provide selective CD28 co-stimulation of T cells, activating them when bound to tumor cells, and we are conducting preclinical studies of internal CD28 candidates.

Under our two collaborations with Janssen Biotech, Inc.

(Janssen), we are applying our bispecific technologies to create and characterize CD28 bispecific antibody candidates against a prostate tumor target, and against multiple B cell targets.

TME activator candidates:

we expanded the functionality of our bispecific Fc platform with a suite of tumor microenvironment (TME) activators that have been designed to promote tumor-selective T-cell activation by targeting multiple checkpoints or co-stimulating receptors.

These candidates incorporate our Xtend technology for longer half-life.

We are currently conducting Phase 1 studies for three TME activator candidates:

XmAb717, XmAb841 and XmAb104.

Our tumor microenvironment (TME) activators have been designed to promote tumor-selective T-cell activation by targeting multiple checkpoints or co-stimulating receptors.

These candidates also incorporate our Xtend™ technology for longer half-life.

We are currently advancing vudalimab in Phase 2 clinical development and are conducting Phase 1 studies for two additional TME activator candidates:

XmAb841 and XmAb104.

Cytokine candidates:

we have expanded the use of our bispecific Fc platform to engineer novel cytokine candidates, which are not antibodies but fusions of a heterodimeric Fc domain and immune signaling proteins.

Our cytokine candidates are potency tuned to improve therapeutic index and incorporate our Xtend technology for longer half-life.

XmAb306 (RO7310729), formerly XmAb24306, is an IL-15/IL-15Ra-Fc fusion, which we believe is a promising candidate for oncology combination therapies, and our partner Genentech is conducting a Phase 1 dose-escalation study.

A second IL-15 cytokine candidate, which is engineered with a target-specific binding arm for immune cell targeting, is also being explored in preclinical studies.

XmAb564 is a wholly owned IL-2-Fc fusion that we intend to develop for the treatment of patients with autoimmune diseases.

In January 2021, the IND application for XmAb564 was allowed by the FDA, and we plan to initiate a Phase 1 study in healthy volunteers for this candidate in early 2021.

We have also expanded the use of our XmAb bispecific Fc domain to engineer novel cytokine candidates, which are not antibodies, but fusions of a heterodimeric Fc domain and immune signaling proteins.

We engineer our cytokine candidates with reduced potency to improve therapeutic index and with our Xtend technology for longer half-life.

Two XmAb cytokine candidates are being evaluated in Phase 1 studies:

XmAb306 (RO7310729) and XmAb564.

We continue to invest in our protein engineering efforts to identify novel technologies and drug candidates.

Other XmAb Fc Technologies

We have also designed additional XmAb Fc technologies and XmAb drug candidates.

We have successfully partnered our technologies and many drug candidates, and we will continue to seek additional partnering and licensing opportunities for these technologies and candidates.

Other XmAb Fc Domains

We have also created additional XmAb Fc domains, and we have successfully entered partnerships for these technologies and for XmAb drug candidates that incorporate them.

We will continue to seek additional partnering and licensing opportunities for these Fc domains.

Additional XmAb Fc domains include:

2 unchanged sentences

Xtend™ Fc Domain – extended antibody half-life, targeting the receptor FcRn on endothelial cells.

Approved or Authorized Medicines Engineered with XmAb Fc Domains

Currently three medicines that have been developed with our XmAb Fc domains are now marketed or made available by our partners.

These medicines generated $80.3 million in royalty revenue for us in 2021, which has partially offset our internal development costs.

● Sotrovimab :

Vir Biotechnology, Inc.

and its partner GlaxoSmithKline Plc have made available sotrovimab, an antibody that targets the SARS-CoV-2 virus, which received an emergency use authorization (EUA) from the United States Food and Drug Administration (FDA) for the treatment of mild-to-moderate COVID-19 in high-risk adults and pediatric patients.

Sotrovimab has been granted a marketing authorization in the European Union (EU), approved via Japan’s Special Approval for Emergency Pathway in Japan, and granted conditional,

provisional, or temporary authorizations in 15 other countries.

GSK supplies sotrovimab under the name Xevudy .

Sotrovimab incorporates our Xtend Fc domain for longer duration of action.

● Ultomiris ® (ravulizumab-cwvz) :

Alexion’s Ultomiris is approved in the U.S., Europe, and Japan for the treatment of patients with paroxysmal nocturnal hemoglobinuria (PNH) and for the treatment of patients with atypical hemolytic uremic syndrome (aHUS).

● Monjuvi ® (tafasitamab-cxix) :

In 2020, the FDA approved Monjuvi under accelerated approval.

Monjuvi is a CD19-directed cytolytic antibody indicated in combination with lenalidomide for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) not otherwise specified, including DLBCL arising from low grade lymphoma, and who are not eligible for autologous stem cell transplant (ASCT).

This indication is approved under accelerated approval based on overall response rate.

Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).

In August 2021, the European Commission granted conditional marketing authorization for Minjuvi ® (tafasitamab) in combination with lenalidomide, followed by tafasitamab monotherapy, for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) who are not eligible for autologous stem cell transplantation (ASCT).

MorphoSys is also conducting studies of tafasitamab in additional B-cell indications.

Tafasitamab was created and initially developed by us.

Tafasitamab is co-marketed by Incyte and MorphoSys under the brand name Monjuvi in the U.S.

and is marketed by Incyte under the brand name Minjuvi in the EU.

Incyte has exclusive commercialization rights to tafasitamab outside the U.S.

Monjuvi ® and Minjuvi ® are registered trademarks of MorphoSys AG.

Drug Candidates in Clinical Development

Currently 20 drug candidates in clinical development have been engineered with one or more of our Fc technologies, and one incorporates our DN-TNF technology.

Ten of the candidates that are being advanced by us and our partners have been engineered with our bispecific Fc domain for dual targeting and are bispecific antibody and cytokine candidates;

one candidate in clinical development incorporates our immune inhibitor Fc domain, and seven candidates incorporate our cytotoxic or Xtend Fc domains.

There are currently 21 clinical-stage drug candidates or marketed medicines that have been developed with one or more of our Fc technologies.

A partner is also advancing a drug candidate that incorporates our DN-TNF technology.

Co-developed with Partners

Developed by Partners

Plamotamab (XmAb13676)

Vibecotamab (XmAb14045)

XmAb717 (XmAb20717)

XmAb306/RG6323 (XmAb24306)

Tidutamab (XmAb18087)

XmAb841 (XmAb22841)

XPro1595/INB03/Quellor™

XmAb104 (XmAb23104)

XmAb564 (XmAb27564)

Elipovimab (GS-9722)

XmAb698 (AMG 424)

Marketed by Partners

XmAb306/RG6323

SARS-CoV-2 mAb Duo (BMS)

Novartis bispecific antibody

Xpro1595/INB03

*Alexion and MorphoSys are conducting additional Phase 3 studies in new indications with these candidates.

XmAb Bispecific Fc Drug Candidates

Currently 10 drug candidates that have been engineered with our bispecific Fc domain are in clinical development.

Six candidates are wholly owned and are being evaluated by us in Phase 1 studies.

We are co-developing two candidates with partners.

In addition, partners are advancing two bispecific antibody candidates through clinical development.

We regularly evaluate our portfolio of candidates and make additional investments in candidates with promising early-stage clinical data, partner out other candidates, and stop development of candidates where early clinical data does not support further investment.

● We initiated Phase 2 studies for our vudalimab and tidutamab programs,

● We licensed the worldwide rights to our plamotamab and obexelimab programs to strategic biopharmaceutical partners, and

● We stopped development of the vibecotamab program.

XmAb Bispecific Fc Drug Candidates in Clinical Development

Currently, 9 XmAb drug candidates that have been engineered with our XmAb bispecific Fc domain are in clinical development.

● Five candidates are wholly owned and are being evaluated by us in Phase 2 or Phase 1 studies;

● Two candidates are being co-developed with partners;

● Two additional candidates are being advanced by our partners.

Additional candidates are advancing through the preclinical stages of development.

Drug candidates with our bispecific Fc domain, both bispecific antibodies and cytokines, in clinical development include:

Vudalimab (XmAb717) is a bispecific antibody that targets PD-1 and CTLA-4, two immune checkpoint receptors, to selectively activate the tumor microenvironment, and it is being developed for patients with metastatic castration-resistant prostate cancer (mCRPC) and other solid tumor types.

Xencor has initiated a Phase 2 clinical study of vudalimab in patients with mCRPC, as a monotherapy or in combination depending on molecular subtype, and a Phase 2 clinical study in patients with advanced gynecologic and genitourinary malignancies, as well as clinically defined high-risk mCRPC.

We presented updated data from the Phase 1 dose-escalation and expansion study at the Annual Meeting of the Society for Immunotherapy of Cancer (SITC) in November 2021.

110 patients had been treated at the 10 mg/kg recommended dose level in dose-escalation (n=7) and in five dose expansion cohorts:

melanoma (n=20), renal cell carcinoma (RCC, n=21), non-small cell lung cancer (NSCLC, n=20), CRPC (n=21) and other cancers without approved checkpoint therapies (n=21).

The safety analysis includes all 110 patients, who were a median of 65 years old and were heavily pretreated, having a median of four prior systemic therapies.

65% of patients had received at least one prior checkpoint therapy, and 25% had received at least two prior checkpoint therapies.

Vudalimab was generally well-tolerated, and the most common treatment-related adverse events were immune-related adverse events (irAEs).

The most common irAEs of any grade were rash (45.5%), pruritus (30.9%), transaminase increases (23.6%), diarrhea (11.8%), hypothyroidism (9.1%), infusion related reaction (8.2%) and myalgia (8.2%).

The efficacy analysis included 78 evaluable patients receiving any amount of vudalimab, who had been followed for at least two cycles.

Complete responses were observed in a patient with BRCA1+ high-grade serous ovarian cancer and in a patient with melanoma.

Partial responses were observed in patients with melanoma (n=2), RCC (n=3), NSCLC (n=2) and CRPC (n=2).

The objective response rate (ORR) across cohorts was 14.1% (11/78).

All responses in patients with melanoma and CRPC and two responses in patients with RCC were confirmed.

All responders, except those with CRPC, had received prior checkpoint inhibitor therapy.

The median duration of response, unadjusted, for all responders was 18.3 weeks.

The median duration of response, unadjusted, for patients with RCC was 24.1 weeks, and two patients remained on treatment.

Of the 12 efficacy-evaluable patients with CRPC, four had measurable disease and follow-up RECIST assessments, including the two CRPC responders.

Six additional patients with CRPC, but without measurable disease, experienced a best overall response of non-CR/non-PD, as stable disease cannot be determined without measurable disease.

The two CRPC responders had visceral and nodal metastases, had response durations of 41.3 and 27.0 weeks, were without progression on bone scans and had confirmed prostate-specific antigen (PSA) reductions of more than 50% from baseline.

Among twelve patients with baseline and follow-up PSA assessments, including the two responders, 33% (4/12) had PSA reductions greater than 50%.

Plamotamab is a bispecific antibody that targets CD20, an antigen on B-cell tumors, and CD3, an activating receptor on T cells.

In February 2017, we dosed the first patient in an open-label, Phase 1, multiple-dose, dose escalation study to assess the safety, tolerability, and preliminary anti-tumor activity of plamotamab in patients with B-cell malignancies.

At the ASH Annual Meeting in December 2019, we presented preliminary safety and anti-tumor activity of plamotamab, including from patients with relapsed or refractory non-Hodgkin’s lymphoma (NHL).

We are enrolling patients in the ongoing dose-escalation study, and we are planning to initiate additional studies for plamotamab in 2021 including a Phase 1/2 study evaluating the combination of

plamotamab, tafasitamab (Monjuvi) and lenalidomide in patients with relapsed or refractory DLBCL, an aggressive type of NHL.

XmAb717 is a bispecific antibody that targets PD-1 and CTLA-4, two immune checkpoint receptors, to selectively activate the tumor microenvironment, and it is being developed in multiple types of solid tumors, including for patients with castration-resistant prostate cancer.

In July 2018, we dosed the first patient in an open-label Phase 1 dose-escalation and expansion study to assess the safety, tolerability, and preliminary anti-tumor activity of XmAb717 in patients with selected solid tumors.

We presented updated data from the study at the Annual Meeting of the Society for Immunotherapy of Cancer (SITC) in November 2020.

In the study's escalation phase, a dose of 10 mg/kg was identified as the recommended dose for the multi-cohort, parallel-group expansion phase, based on an observation of consistent proliferation of both CD8+ and CD4+ T cells, indicative of dual checkpoint blockade, and a complete response (CR) in one patient with melanoma.

At the data cut off on September 30, 2020, 89 patients had been treated at the recommended dose in five dose expansion cohorts that enrolled patients with melanoma (n=20), renal cell carcinoma (RCC, n=11), non-small cell lung cancer (NSCLC, n=20), castration-resistant prostate cancer (CRPC, n=18) and other cancers without approved checkpoint therapies (n=20).

XmAb717 was generally well-tolerated, and the most common treatment-related adverse events were immune-related adverse events (irAEs);

however, rates of irAEs, including colitis, were lower than typically observed with CTLA-4 blockade.

With exceptions for rash and increases in transaminases, other Grade 3 or higher irAEs were reported for no more than three patients each.

The efficacy analysis included 42 evaluable patients at the recommended dose level.

A complete response was observed in a patient with melanoma (1/10), and partial responses were observed in multiple tumor types, including melanoma (2/10), RCC (1/4), NSCLC (2/14), CRPC (1/4), and ovarian cancer (1/5).

The objective response rate across cohorts was 19.0% (8/42).

Across the expansion cohorts, approximately half of evaluable patients had at least 10% tumor shrinkage from baseline assessments, and nearly all these reductions occurred in patients with prior checkpoint inhibitor treatment.

The median duration of response was 119 days at the time of the data cut off, and 24 patients remained on treatment.

Of nine patients with prostate cancer who had baseline and follow-up prostate-specific antigen (PSA) assessments, one achieved a PSA reduction of greater than 50 percent.

Two additional patients achieved reductions of greater than 30 percent, one of whom had an unconfirmed partial response by RECIST.

Six of these nine patients remained on therapy as of the cut-off date.

In the first half of 2021, we plan to initiate a Phase 1b study of XmAb717 for patients with certain molecular subtypes of CRPC, as a monotherapy or in combination depending on the subtype, as these patients represent a high unmet medical need.

Vibecotamab is a bispecific antibody that targets CD123, an antigen on acute myeloid leukemia (AML) cells and leukemic stem cells, and CD3, an activating receptor on T cells.

It is being developed in collaboration with our partner Novartis Institutes for BioMedical Research, Inc.

(Novartis) and is being evaluated in a Phase 1 study.

In September 2016, we dosed the first patient in an open-label, multiple-dose, dose escalation study to assess the safety, tolerability, and preliminary anti-tumor activity of vibecotamab in patients with relapsed or refractory AML and other CD123-expressing hematologic malignancies.

The study is ongoing, and additional patients are being enrolled.

We presented updated data from the study at the American Society of Hematology (ASH) Annual Meeting in December 2020.

At data cut off on October 28, 2020, 112 heavily pretreated patients with relapsed or refractory AML had received vibecotamab.

Cytokine release syndrome (CRS) was the most common toxicity occurring in 61% of patients (n=68), and 9% of patients (n=10) experienced CRS at Grade 3 or higher.

The majority of CRS was observed in the first dose and was generally manageable with premedication.

Additional mitigation measures included selecting a lower priming dose, avoiding weekly dose step-up, and more frequent dosing in the first week to allow a higher cumulative exposure and to avoid the potential CD123 antigen sink.

There was no evidence of drug related myelosuppression.

Neurological events were infrequent and primarily Grade 1 and Grade 2 headaches.

The efficacy analysis included 54 evaluable patients who received a dose of at least 0.75 mcg/kg, completed at least the first cycle of treatment and had at least one post-treatment disease assessment.

Two patients achieved complete remission (CR), and three patients achieved a CR with incomplete hematologic recovery.

Additionally, two patients reached a morphologic leukemia-free state, and one patient experienced partial remission, as assessed by the investigator.

The overall response rate (ORR) was 15% (n=8/54).

Biomarker analyses suggest that low baseline leukemic burden and low PD-1 expression on CD4+ and CD8+ T cells are independent predictors of response.

Seven responders had a baseline blast count less than or equal to 25% blasts in bone marrow.

The ORR increased to 26% (n=7/27) when using this threshold to define the population with low disease burden for the analyses.

In 2021, pending final dose escalation data and agreement with our partner, Novartis, we plan to initiate additional clinical studies evaluating vibecotamab.

In October 2021, we entered into a global collaboration and license agreement with Janssen to advance plamotamab and XmAb CD28 bispecific antibody combinations for the treatment of patients with B-cell malignancies, which expands our strategy to develop multiple highly active, chemotherapy-free regimens to treat patients with B-cell cancers.

Janssen received worldwide exclusive development and commercial rights

to plamotamab, and we will collaborate with Janssen on further clinical development of plamotamab, with us paying 20% of costs, including those for a subcutaneous formulation study anticipated to enter clinical trials in 2022.

We will continue, at our own expense, a Phase 1/2 combination study of plamotamab, tafasitamab (Monjuvi), and lenalidomide in patients with relapsed or refractory diffuse large B cell lymphoma (DLBCL), an aggressive type of non-Hodgkin lymphoma, and we plan to initiate the study in early 2022.

We presented updated data from Part B and Part C of a Phase 1 dose-escalation study at the American Society of Hematology Annual Meeting in December 2021.

Part B escalated dosing on administrations after the priming dose (doses between 80 and 360 mcg/kg).

Part C established a step-up dosing regimen with higher, flat and less frequent dosing.

The schedule, an intravenous, 50 mg flat dose every two weeks after step-up dosing during the first two cycles of treatment, was generally well tolerated and was determined to be the recommended Phase 2 dose.

The safety population included 50 patients in Part B (38 DLBCL, 12 FL) and 14 patients in Part C (8 DLBCL, 4 FL, 1 marginal zone lymphoma, 1 mantle cell lymphoma).

Patients were heavily pretreated.

The most common Grade 3 or 4 treatment-emergent adverse events (AEs) across all patients were anemia (21%), neutropenia (19%), hypophosphatemia (11%), thrombocytopenia (11%) and lymphopenia (10%).

Four patients (5%) experienced Grade 3 or 4 cytokine release syndrome (CRS), each instance on the first dose, and no patients experienced Grade 3 or 4 CRS in Part C of the study.

The rate of CRS of any grade fell from 74% in Part B to 57% in Part C.

CRS was generally manageable with premedication.

The efficacy analysis included 47 evaluable patients with either DLBCL or FL who were treated in Part B (n=38) or in Part C (n=9).

The ORR was 51% (24/47), and complete responses were observed in 12 patients (26%).

The median duration of response was 225 days for DLBCL and 171 days for FL, with six patients continuing to respond to plamotamab monotherapy.

In Part C, patients had generally more advanced disease and poorer responses to prior therapy.

Of the 14 patients in Part C, eight patients received prior CAR-T and three patients received NK cell therapy;

two of these patients received both.

All eight patients with DLBCL received prior CAR-T therapy.

In Part C, safety events were generally mild or moderate in severity.

Grade 3 or 4 AEs experienced by more than 5% of patients included anemia (14%), lymphopenia (14%) and one patient each (7%) experiencing neutropenia, thrombocytopenia, decreases in neutrophil count, transaminase increases, fatigue and gamma-glutamyl transferase increases.

The ORR was 100% (4/4) for FL, and CRs were observed in two patients (50%).

For DLBCL, the ORR was 40% (2/5), and a CR was observed in one patient (20%).

All 5 evaluable patients with DLBCL received prior CAR-T therapy, and two evaluable patients with DLBCL received prior NK cell therapy.

Expansion cohorts are actively recruiting patients with DLBCL and FL and are dosing using the recommended Phase 2 regimen to further evaluate the safety and efficacy of plamotamab monotherapy.

We plan to present data from these cohorts in the second half of 2022.

Tidutamab is a bispecific antibody that targets somatostatin receptor 2, or SSTR2, a target on many neuroendocrine-like tumor types, and CD3.

In February 2018, we dosed the first patient in an open-label, Phase 1, dose-escalation study to assess the safety, tolerability, and preliminary anti-tumor activity of tidutamab in patients with neuroendocrine tumors (NET) or gastrointestinal stromal tumors (GIST).

In October 2020, we presented initial dose-escalation data in patients with NETs at the North American Neuroendocrine Tumor Society’s 2020 Multidisciplinary NET Medical Virtual Symposium (NANETS).

Tidutamab was generally well tolerated at the recommended dose identified for the expansion portion of the study, a 0.3 mcg/kg priming dose and subsequent 1.0 mcg/kg repeated doses.

Analysis of peripheral blood biomarkers indicated that tidutamab induced acute and sustained T-cell activation at the recommended dose for expansion.

The analysis also indicated a dose-dependent increase in proliferation and activation markers on CD8-positive effector T cells, which is consistent with tidutamab's mechanism of action.

Fourteen patients, including 12 across the first three dose-escalation cohorts and two in the expansion cohort, were included in the analysis to describe clinical activity.

The best overall response was stable disease, with a disease control rate of 43% and a median duration of treatment of approximately seven months.

Completion of enrollment in the expansion cohort and longer follow-up are required to evaluate progression-free survival and the clinical utility of tidutamab in this NET patient population.

Because tidutamab induced sustained activation of cytotoxic T cells and engagement of the SSTR2 target, as designed, and has an encouraging safety profile, we plan to initiate a clinical study for tidutamab in patients with Merkel cell carcinoma and small cell lung cancer, SSTR2-expressing tumor types known to be responsive to immunotherapy, in early 2021.

XmAb841 is a bispecific antibody that targets CTLA-4 and LAG-3, also an immune checkpoint receptor, and is being developed in multiple oncology indications.

We are advancing XmAb841 in combination with an anti-PD-1 drug to create a triple checkpoint blockade.

In May 2019, we dosed the first patient in an open-label, Phase 1, dose-escalation study to assess the safety, tolerability, and preliminary anti-tumor activity of XmAb841 in patients with selected solid tumors.

We are enrolling patients to a single-agent dose-escalation portion cohort and a cohort combining XmAb841 with pembrolizumab.

Dose-escalation and expansion data from the Phase 1 study in patients with neuroendocrine tumors (NET) indicates that tidutamab was generally well tolerated at the recommended dose identified for the expansion portion of the study.

Tidutamab induced sustained activation of cytotoxic T cells and engagement of the SSTR2 target and demonstrated an encouraging safety profile.

We are enrolling patients in a Phase 2 clinical study for tidutamab in patients with Merkel cell carcinoma and small cell lung cancer, which are SSTR2-expressing tumor types known to be responsive to immunotherapy.

XmAb306 (RO7310729) is an IL15/IL15-receptor alpha complex fused to our bispecific Fc domain (IL15/IL15Rα-Fc).

This cytokine was engineered for reduced potency, and the Fc domain incorporates our Xtend technology for extended half-life.

Xencor is co-developing the program in collaboration with Genentech, a member of the Roche Group.

Genentech is conducting a Phase 1 dose-escalation study of XmAb306 as a single agent and in combination with atezolizumab.

Additional studies of XmAb306 in combination with other agents are being planned.

In November 2021, we announced preliminary data from the Phase 1 study, while further dose escalation in both study arms continues.

At the time, the study had enrolled six cohorts in a monotherapy arm and four cohorts in an atezolizumab combination arm.

XmAb306 was generally well tolerated as both a monotherapy and in combination with atezolizumab.

No dose-limiting toxicities or treatment-related serious adverse events had been observed.

Assessments of pharmacokinetics indicated that XmAb306 has a multi-day circulating half-life, which is consistent with its reduced-potency design and data generated in preclinical studies.

Unconfirmed responses, as evaluated by RECIST criteria, had been observed in multiple tumor types, including in a patient treated with XmAb306 monotherapy.

The study had recently reached dose levels that promote T cell activity, and evidence of peripheral effector T cell proliferation had been observed.

Consistent and robust dose-dependent natural killer (NK) cell expansion and NK cell accumulation upon repeat dosing had been observed for multiple NK cell subsets, including mature NK cells.

Significant NK cell expansion and accumulation was observed beginning in lower dose cohorts, and at higher dosing cohorts NK cell expansion had reached 40- to 100-fold higher levels than baseline and had been sustained for weeks throughout dosing.

XmAb104 is a bispecific antibody that targets PD-1 and ICOS, an immune co-stimulatory receptor, and is being developed in multiple oncology indications.

In May 2019, we dosed the first patient in a an open-label, Phase 1, dose-escalation study to assess the safety, tolerability, and preliminary anti-tumor activity of XmAb104 in patients with selected solid tumors.

We continue to enroll patients with select solid tumors in the Phase 1 dose escalation study.

XmAb306 (RO7310729) is an engineered cytokine, an IL15/IL15-receptor alpha complex fused to our bispecific Fc domain (IL15/IL15Rα-Fc), and the Fc domain incorporates our Xtend technology for extended half-life.

We believe a broad combination development strategy will be critical to realize the potential of IL-15 cytokines like XmAb306 in oncology.

In February 2019, we entered into a research and license agreement with Genentech, Inc.

Hoffmann-LaRoche Ltd.

(collectively Genentech), to develop and commercialize novel IL-15 cytokine therapeutics, whereby the companies are co-developing XmAb306 and other potential IL-15 programs.

Genentech is conducting a Phase 1 dose-escalation study of XmAb306 as a single agent and in combination

with atezolizumab.

AMG 509 is a STEAP1 x CD3 bispecific antibody candidate for the treatment of patients with prostate cancer.

In December 2019, Amgen Inc.

initiated a Phase 1 clinical study with AMG 509, a 2+1 bispecific antibody candidate that was developed with our bispecific Fc technology under our collaboration with them.

Amgen is currently enrolling patients in a Phase 1 study of AMG 509 in patients with metastatic castration-resistant prostate cancer (mCRPC).

XmAb698 (AMG 424) , a CD38 x CD3 bispecific antibody candidate, was developed in the Amgen collaboration and was being advanced by Amgen in a Phase 1 study.

In 2020, Amgen notified us that they were terminating the study, and the rights to the candidate reverted to us under the Agreement.

We are currently evaluating this candidate and plan to initiate a new study for it in 2021.

We are conducting an open-label, Phase 1, dose-escalation study to assess the safety, tolerability, and preliminary anti-tumor activity of XmAb104 in patients with selected solid tumors.

We continue to enroll patients with select solid tumors in the dose expansion portion of the study, evaluating XmAb104 as a monotherapy and in combination with ipilimumab, an anti-CTLA4 antibody.

XmAb841 is a bispecific antibody that targets CTLA-4 and LAG-3, also an immune checkpoint receptor, and is being developed in multiple oncology indications.

We are advancing XmAb841 in combination with an anti-PD-1 drug to create a triple checkpoint blockade and conducting an open-label, Phase 1, dose-escalation study to assess the safety, tolerability, and preliminary anti-tumor activity of XmAb841 in patients with selected solid tumors.

We recently completed dose escalation in monotherapy and pembrolizumab combination cohorts and are enrolling in the expansion portion of the study.

XmAb564 is a monovalent, potency-reduced interleukin-2 Fc (IL-2-Fc) fusion protein, engineered to selectively activate and expand regulatory T cells (Tregs) for the potential treatment of patients with autoimmune diseases.

XmAb564 is engineered with reduced binding affinity for IL-2's beta receptor and increased binding affinity for its alpha receptor.

In preclinical studies, XmAb564 was well-tolerated, promoted the selective and sustained expansion of Tregs and exhibited a favorable pharmacokinetic profile.

We are conducting a randomized, double-blind, placebo-controlled Phase 1 clinical study to evaluate the safety and tolerability of a single dose of XmAb564, administered subcutaneously in healthy adult volunteers.

AMG 509 is a STEAP1 x CD3 2+1 bispecific antibody that our partner Amgen is advancing for the treatment of patients with prostate cancer.

The XmAb 2+1 multivalent format enables higher binding capability for STEAP1 expressing cells.

Amgen is currently enrolling patients in a Phase 1 study of AMG 509 in patients with mCRPC.

In February 2022, Amgen presented encouraging, preliminary pharmacodynamic activity by induction of percent maximum PSA decline among 30 patients in the study, which provides an early signal of activity and validation of the potential of the XmAb 2+1 format.

XmAb819 is a first-in-class ENPP3 x CD3 XmAb 2+1 bispecific antibody that we are developing for patients with renal cell carcinoma (RCC).

The XmAb 2+1 multivalent format enables greater selectivity for ENPP3 expressing tumor cells compared to normal cells, which also express ENPP3 at lower levels.

We are initiating a Phase 1 study evaluating XmAb819 in patients with RCC.

Novartis XmAb undisclosed bispecific antibody candidate:

in December 2019, Novartis initiated a Phase 1 clinical study with an undisclosed bispecific antibody candidate that was developed with our bispecific Fc technology under our collaboration with them.

XmAb Immune Inhibitor Fc Candidates

AIMab7195 (XmAb7195) uses our XmAb Immune Inhibitor Fc Domain and is designed to reduce blood serum levels of IgE, which mediates allergic responses and allergic disease.

In February 2020, we licensed this drug candidate to Aimmune Therapeutics, Inc., now a wholly owned subsidiary of Nestlé S.A., which is advancing the candidate in clinical studies for allergic indications.

Obexelimab targets CD19 with its variable domain and uses our XmAb Immune Inhibitor Fc Domain, which is designed to inhibit the function of B cells, an important component of the immune system.

We believe that obexelimab has the potential to address a key unmet need in autoimmune diseases due to its combination of potent reversible B-cell inhibition without B-cell depletion, enabling the immune system to resume natural function once treatment is no longer needed.

We are exploring opportunities to continue development of obexelimab with partners.

XmAb Cytotoxic Fc and Xtend Candidates

Currently, one drug engineered with our Xtend Fc Domain and one drug we engineered with our XmAb Cytotoxic Fc Domain are marketed commercially by partners.

In addition, our partners are advancing eight clinical programs with antibodies engineered with XmAb technologies through clinical development:

three programs are in Phase 3, one program is in Phase 2, and four programs are in Phase 1.

Other partners are conducting preclinical studies of drug candidates engineered with these XmAb technologies.

● MorphoSys AG:

In 2020, Monjuvi was approved for marketing by the U.S.

FDA for the treatment of certain adult patients with DLBCL.

Tafasitamab’s marketing authorization application is under review by European regulators, and MorphoSys is also conducting studies of tafasitamab in additional B-cell indications.

● Alexion Pharmaceuticals, Inc.:

Ultomiris was approved for marketing by the U.S.

FDA in 2018, and Alexion is conducting Phase 3 studies of Ultomiris in additional neurology and nephrology indications.

● Gilead Sciences, Inc.:

Gilead is advancing HIV candidates in clinical development that are broadly neutralizing antibodies that incorporate our Fc technologies.

Gilead is conducting Phase 1 clinical studies of elipovimab (GS-9722) and GS-9723.

XmAb, Xtend, and Cytotoxic Fc Drug Candidates in Clinical Development

Currently, two drugs engineered with our Xtend Fc Domain and one drug we engineered with our XmAb Cytotoxic Fc Domain are marketed commercially by partners.

In addition to these approved drugs, our partners are advancing six clinical-stage programs with antibodies engineered with XmAb, Xtend, and/or Cytotoxic Fc Domains, including:

● Vir Biotechnology, Inc.:

Vir is advancing three candidates in clinical development.

VIR-7831 is an antibody that is being investigated in a Phase 3 study as a potential treatment for the treatment of patients with COVID-19.

VIR-3434 is being evaluated in a Phase 2 combination study as a potential treatment for patients with hepatitis B virus infection.

VIR-2482 is being evaluated in a Phase 1/2 study as a universal prophylactic for influenza A.

VIR-3434 is being evaluated in a Phase 1 study as a potential treatment for patients with hepatitis B virus infection.

● Omeros Corporation, Viridian Therapeutics, Inc.

and Catabasis Pharmaceuticals, Inc.

each are conducting preclinical studies with candidates that incorporate our XmAb technologies.

In October 2017, we licensed the rights to XPro1595, a proprietary TNF inhibitor candidate to INmune Bio, Inc.

INmune is currently conducting a Phase 2 study in hospitalized patients with respiratory symptoms from COVID-19 infection, as Quellor™;

a Phase 1 study in patients Alzheimer’s disease, as XPro1595;

and a Phase 1 study in patients with advanced cancers, as INB03.

VIR-7832 is being evaluated in a Phase 1b/2a trial of adults with mild-to-moderate COVID-19;

● Bristol-Myers Squibb:

Bristol-Myers Squibb’s SARS-CoV-2 mAb Duo antibody combination therapy (BMS-986414 + BMS-986413) is being evaluated in the Phase 2/3 NIH ACTIV-2 trial in treating COVID-19 in outpatients;

● Gilead Sciences, Inc.:

Gilead is supporting HIV candidates in clinical development that are broadly neutralizing antibodies that incorporate our Fc technologies;

● Our partners are conducting preclinical studies of additional drug candidates engineered with these XmAb Fc domains.

Other Clinical Stage Drug Candidates

● AIMab7195 (XmAb7195) uses our XmAb Immune Inhibitor Fc Domain and is designed to reduce blood levels of IgE, which mediates allergic responses and allergic disease.

● Obexelimab targets CD19 with its variable domain and uses our XmAb Immune Inhibitor Fc Domain, which is designed to inhibit the function of B cells, an important component of the immune system.

In November 2021, we licensed this drug candidate to Zenas BioPharma, which is developing this candidate in autoimmune disease.

● Xpro1595 is a proprietary TNF inhibitor candidate which we licensed to INmune Bio, Inc., in October 2017.

INmune is currently advancing Xpro1595 through clinical development for patients with Alzheimer’s disease, mild cognitive impairment and treatment-resistant depression.

Collaborations, Partnerships and Licensing Arrangements

A key part of our business strategy is to leverage our protein engineering capabilities, XmAb technologies, and drug candidates with partnerships, collaborations and licenses.

A key part of our business strategy is to leverage our protein engineering capabilities, XmAb technologies, and XmAb drug candidates with partnerships, collaborations, and licenses.

Through these arrangements we generate revenues in the form of upfront payments, milestone payments, and royalties.

2 unchanged sentences

● Product Licenses:

Genentech, MorphoSys AG, Nestlé S.A., Novartis AG, INmune Bio, Inc.

Janssen Biotech, Inc., Genentech, MorphoSys AG, Nestlé S.A., Zenas BioPharma, INmune Bio, Inc.

● Novel Bispecific Antibody Collaborations:

1 unchanged sentence

● Technology Licensing Agreements:

Alexion Pharmaceuticals, Inc., Vir Biotechnology, Inc., Gilead Sciences, Inc., Omeros Corporation, Viridian Therapeutics, Inc., Catabasis Pharmaceuticals, Inc.

Alexion Pharmaceuticals, Inc., Vir Biotechnology, Inc., Gilead Sciences, Inc., Bristol-Myers Squibb Company, Novartis AG, Omeros Corporation, Viridian Therapeutics, Inc., Astria Therapeutics, Inc.

● Strategic Collaborations:

1 unchanged sentence

Product Licenses

Product licenses are arrangements in which we have internally developed drug candidates, and based on a strategic review we licensed partial or full rights to third parties to continue development and potential commercialization.

Product licenses are arrangements in which we license to third parties partial or full rights to develop and commercialize our internally developed drug candidates.

We seek partners that can provide infrastructure and resources to successfully develop our drug candidates, have a track record of successfully developing and commercializing medicines, or have a portfolio of development-stage candidates and commercialized medicines which could potentially be developed in rational combinations with our drug candidates.

Janssen Biotech, Inc.

In October 2021, we entered into an agreement with Janssen Biotech, Inc.

(Janssen) to develop, manufacture, and commercialize plamotamab and pursuant to which we, together, will conduct research and development activities to discover novel CD28 bispecific antibodies against undisclosed B cell tumor targets.

Janssen will receive exclusive worldwide rights, subject to certain Xencor opt-in rights, to develop, manufacture and commercialize pharmaceutical products that contain one or more of such CD28 bispecific antibodies.

We received a $100.0 million upfront payment, and Johnson & Johnson Innovation, JJDC, Inc., purchased $25.0 million of newly issued unregistered shares of our common stock.

In addition, we are eligible to receive milestone payments and royalties on net sales as follows:

● Plamotamab.

We are eligible to receive up to a total of $517.5 million in milestone payments, which includes $120.0 million in development milestones, $137.5 million in regulatory milestones, and $260.0 million in sales milestones, as well as tiered royalties in the mid-teen to low-twenties percent range on net sales of products containing plamotamab, including CD28/plamotamab combination products.

● CD28 Licensed Antibodies.

We are eligible to receive up to a total of $670.0 million in milestone payments, which includes an aggregate of $169.4 million in development milestones and $240.6 million in regulatory milestones.

For any products containing CD28 bispecific antibodies, but excluding CD28/plamotamab combination products, we are eligible to receive $260.0 million in sales milestones, as well as tiered royalties in the high-single digit to low-double digit range on net sales.

We are collaborating with Janssen on further clinical development of plamotamab with Janssen paying 80% and the Company paying 20% of costs.

We are conducting, at our own expense, a clinical collaboration to evaluate the combination of plamotamab, tafasitamab, and lenalidomide in patients with B-cell lymphoma after which Janssen may opt into cost sharing to further develop the combination after establishing proof of concept.

We are generally responsible for conducting research activities, and Janssen is generally responsible for all development, manufacturing, and commercialization activities for CD28 bispecific antibodies that are advanced.

Independent of plamotamab development activities, upon clinical proof-of-concept for a CD28 bispecific antibody that is being developed outside of a plamotamab combination, we have the right to opt-in to fund 15% of development costs and, if we opt in to fund such development costs, to perform up to 30% of the detailing efforts in the United States.

We would then be eligible for low-double digit to mid-teen percent royalties on net sales of those products.

In February 2019, we entered into an agreement with Genentech to develop and commercialize novel IL-15 cytokine therapeutics that use our bispecific Fc technology, including XmAb306, declared as a Collaboration Product under the agreement.

3 unchanged sentences

We received an upfront payment of $120.0 million.

We are eligible to receive up to $160.0 million in clinical milestone payments for XmAb306, up to $180.0 million in clinical milestone payments for each new Collaboration Product, and a 45% share of net profits from sales from all Collaboration Products, while also sharing in the net losses at

the same percentage rate.

We are sharing in 45% of development and commercialization costs of Collaboration Products, while Genentech will pay for commercial launch costs.

We are conducting a two-year joint research program with Genentech to discover additional IL-15 programs.

In July 2020, the FDA approved Monjuvi® (tafasitamab-cxix) in combination with lenalidomide for treating certain patients with DLBCL.

Tafasitamab, which we engineered with an XmAb Cytotoxic Fc Domain, is the second product with XmAb technology to be approved by the FDA.

In July 2020, the FDA approved Monjuvi® (tafasitamab-cxix) in combination with lenalidomide for treating certain patients with DLBCL, and the European Commission granted conditional marketing authorization to tafasitamab for treating certain patients with DLBCL, which is marketed as Minjuvi® in Europe, in August 2021.

In 2010, we licensed exclusive worldwide rights to develop and commercialize tafasitamab (formerly MOR208 and XmAb5574) to MorphoSys.

In 2020, we earned a total of $37.5 million in regulatory milestones and royalties of $1.5 million on net sales.

Tafasitamab, which we engineered with an XmAb Cytotoxic Fc Domain, is the second XmAb medicine to be approved by the FDA.

In 2021, we earned $12.5 million in development milestones and royalties of $5.9 million on net sales.

We are also eligible to receive up to $85.5 million in additional milestones for development of tafasitamab in additional oncology indications and $50.0 million in sales milestones across all indications.

We are entitled to receive tiered royalties in the high-single digit to low-double digit percent range on net sales.

Monjuvi is co-commercialized in the U.S.

by MorphoSys and Incyte Corporation.

The European Marketing Authorization Application for tafasitamab is currently under review by the European Medicines Agency.

Tafasitamab is co-marketed by Incyte and MorphoSys under the brand name Monjuvi® in the U.S., and is marketed by Incyte under the brand name Minjuvi® in the EU.

Incyte has exclusive commercialization rights to tafasitamab outside the U.S.

Nestlé S.A./Aimmune Therapeutics, Inc.

5 unchanged sentences

Nestlé is planning additional studies of AIMab7195.

In connection with our June 2016 Collaboration and License Agreement with Novartis (the Novartis Agreement), we granted Novartis certain exclusive rights to research, develop, and commercialize vibecotamab.

We are eligible to receive up to $325.0 million in milestone payments in connection with the development of vibecotamab, including $90.0 million in development milestones, $110.0 million in regulatory milestones, and $125.0 million in sales milestones, and low-double digit royalties on sales of approved products in all territories outside the United States.

We retained the commercialization rights to vibecotamab in the U.S.

We and Novartis are co-developing vibecotamab worldwide and are sharing development costs equally.

INmune Bio, Inc.

In October 2017, we entered into an agreement with INmune Bio, Inc., in which we provided INmune with an exclusive license to our Xpro1595 drug candidate.

In connection with the license, we received 1,585,000 shares of INmune common stock and an option to acquire up to 10% of the outstanding shares of INmune for $10.0 million.

In connection with the license, we received 1,585,000 shares of INmune common stock, an option to acquire up to 10% of the outstanding shares of INmune for $10.0 million, and an option to acquire 108,000 shares of common stock.

In 2021, we sold the option to acquire up to 10% of INmune, and we received $15.0 million in cash proceeds and an additional 192,533 share of INmune common stock.

We also exercised the option to acquire 108,000 shares of common stock for total proceeds of $0.8 million.

We are also eligible to receive a percentage of sublicensing revenue received for Xpro1595 and royalties in the mid-single digit percentage range on the sale of approved products.

INmune is currently conducting a Phase 2 study in hospitalized patients with respiratory symptoms from COVID-19 infection, as Quellor™;

a Phase 1 study in patients Alzheimer’s disease, as XPro1595;

and a Phase 1 study in patients with advanced cancers, as INB03.

Private Company

In November 2020, we entered into an agreement with a newly formed, privately held biotechnology company to which we licensed the exclusive worldwide rights to develop and commercialize three preclinical-stage Fc-engineered drug candidates for autoimmune disease:

INmune is currently planning Phase 2 studies in Alzheimer’s disease, mild cognitive impairment, and treatment-resistant depression, as Xpro1595;

Phase 2 studies in patients with non-alcoholic steatohepatitis, as LIVNate;

and additional studies in MUC4-positive cancers, as INB03.

Zenas BioPharma (Cayman) Limited

In November 2020, we entered into an agreement with Zenas BioPharma (Cayman) Limited (Zenas) to which we licensed the exclusive worldwide rights to develop and commercialize three preclinical-stage Fc-engineered drug candidates for autoimmune disease:

XmAb6755, Xpro9523, and XmAb10171.

These programs incorporate an Xtend Fc Domain, a Cytotoxic Fc Domain, or both.

We received a 15% equity interest in the company, and we will also

receive royalties on net sales of approved products in the mid-single digit to mid-teen percentage range.

We received a 15% equity interest in Zenas, and we will also receive royalties on net sales of approved products in the mid-single digit to mid-teen percentage range.

In November 2021, we entered into a second agreement with Zenas to which we licensed the exclusive worldwide rights to develop and commercialize obexelimab, a bifunctional antibody that targets CD19 with its variable domain and uses our XmAb Immune Inhibitor Fc Domain.

Zenas issued a warrant giving us the right to acquire additional Zenas equity, such that our total equity in Zenas would be 15% of its fully diluted capitalization following the closing of Zenas’ next round of equity financing, subject to certain requirements.

We are also eligible to receive up to $470.0 million based on the achievement of certain clinical development, regulatory and commercialization milestones and are eligible to receive tiered, mid-single digit to mid-teen percent royalties upon commercialization of obexelimab, dependent on geography.

Zenas will have sole responsibility for advancing the research, development, regulatory and commercial activities of obexelimab worldwide.

Novel Bispecific Antibody Collaborations

Novel bispecific antibody collaborations are arrangements in which our partner seeks to create a bispecific antibody using one or more of our XmAb bispecific technologies.

Novel bispecific antibody collaborations are arrangements in which our partner seeks to create an XmAb bispecific antibody using one or more of our bispecific technologies.

Our partners provide an antibody or an antigen against tumors, and we conduct limited research and development activities to create potential bispecific antibody candidates for further development and commercialization by our partners.

Janssen Biotech, Inc.

In November 2020, we entered into an agreement, which became effective in December 2020, with Janssen Biotech, Inc., to develop XmAb bispecific antibodies against CD28 and an undisclosed prostate tumor target, for the potential treatment of patients with prostate cancer.

Under the agreement, we will conduct research activities to develop CD28 bispecific drug candidates for further development by Janssen.

In November 2020, we entered into an agreement, which became effective in December 2020, with Janssen Biotech, Inc.

(Janssen), to develop XmAb bispecific antibodies against CD28 and an undisclosed prostate tumor target, for the potential treatment of patients with prostate cancer.

Under the agreement, we conducted research activities to develop CD28 bispecific drug candidates for further development by Janssen.

Preclinical activities and all clinical development, regulatory and commercial activities will be conducted by Janssen, which has exclusive worldwide rights to develop and commercialize the novel drug candidates developed in the collaboration.

4 unchanged sentences

Both we and Janssen also have the right to access predefined agents from each other’s portfolios to evaluate potential combination therapies in prostate cancer, subject to certain limitations.

In 2021, we received a $5.0 million milestone payment related to Janssen selecting a candidate for further development, and we are eligible to receive an additional $156.9 million in development milestones as the program advances.

Astellas Pharma, Inc.

In March 2019, we entered into an agreement with Astellas Pharma, Inc., under which we applied our XmAb bispecific Fc technology to an antigen pair provided by Astellas and generated bispecific antibody candidates for further certain characterization and testing, and in 2019, we completed delivery of the candidates to Astellas for development and potential commercialization.

Astellas was granted a worldwide exclusive license, with the right to sublicense products in the field created by the research activities.

Astellas has selected a bispecific antibody developed under the

collaboration, ASP2138, a CLDN18.2 x CD3 bispecific antibody, for further development to treat patients with gastric, gastroesophageal, and pancreatic cancers.

We received an upfront payment of $15.0 million, and we are eligible to receive up to $240.0 million in milestones which include $32.5 million in development milestones, $57.5 million in regulatory milestones and $150.0 million in sales milestones and royalties on net sales in the high-single to low-double digit percentage range.

2 unchanged sentences

to develop and commercialize bispecific antibody product candidates using our proprietary XmAb bispecific Fc technology.

We granted Amgen an exclusive license to the rights to our CD38 x CD3 preclinical program, and they developed AMG 424.

In May 2020, Amgen notified us it was terminating its rights with respect to the CD38 x CD3 program, including AMG 424.

Under the terms of the agreement, the rights to the AMG 424 program reverted to us.

We renamed the program XmAb698 and plan to initiate a new study for it in 2021.

Amgen also applied our XmAb bispecific Fc technology to create AMG 509, a STEAP1 x CD3 XmAb 2+1 bispecific antibody.

We have received a total of $60.5 million in upfront and milestone payments and are eligible to receive up to $255.0 million in future development, regulatory and sales milestone payments in total for the STEAP1 x

CD3 program and royalties on net sales.

Amgen applied our XmAb bispecific Fc technology to create AMG 509, a STEAP1 x CD3 XmAb 2+1 bispecific antibody.

In connection with our June 2016 agreement with Novartis, we also applied our XmAb bispecific Fc technology to two target pair antibodies selected by Novartis.

1 unchanged sentence

We are eligible to receive up to $250.0 million in milestone payments for each program which includes $50.0 million in development milestones, $100.0 million in regulatory milestones, and $100.0 million in sales milestones and royalties in the mid-single digit percent range on net sales of approved products.

We completed delivery of one bispecific antibody candidate in 2017 and a second bispecific antibody candidate in 2018.

In December 2019, Novartis dosed the first patient in a Phase 1 study of an undisclosed bispecific antibody candidate, and we received a $10.0 million milestone payment.

We have the right to participate in the development and commercialization of one of these programs prior to submission of an IND for such program.

If we elect to participate in development, we will assume 25% of the worldwide development costs for the program and 50% of commercialization costs and will receive 50% of the U.S.

profits on net sales of the product.

Novartis is conducting a Phase 1 study of an undisclosed bispecific antibody candidate and we received a $10.0 million milestone payment for this program in 2020.

Technology Licensing Agreements

1 unchanged sentence

Our partners are responsible for all research, development and commercialization activities of the drug candidates.

The plug-and-play nature of XmAb technologies allows us to license access to our platforms with no internal research and development activities required of us.

The plug-and-play nature of XmAb Fc domains allows us to license access to our platforms with no internal research and development activities required of us.

Alexion Pharmaceuticals, Inc.

Ultomiris® (ravulizumab-cwvz) was the first antibody incorporating XmAb Fc technology to be approved by the U.S.

FDA for commercial marketing.

It is approved in the U.S., Europe and Japan for the treatment of adult patients with paroxysmal nocturnal hemoglobinuria (PNH) and for the treatment of patients with atypical hemolytic uremic syndrome (aHUS).

Ultomiris® (ravulizumab-cwvz) was the first antibody incorporating XmAb Fc technology to be approved by the FDA for commercial marketing.

It is approved in the U.S.

and multiple global markets for the treatment of patients with paroxysmal nocturnal hemoglobinuria (PNH) and for the treatment of patients with atypical hemolytic uremic syndrome (aHUS).

Ultomiris is commercialized by Alexion Pharmaceuticals, Inc.

1 unchanged sentence

The Xtend technology increased the circulating half-life of Ultomiris by over three-fold compared to Soliris and extended the dosing schedule to bimonthly for Ultomiris compared to biweekly for Soliris.

During 2020, we received a $10.0 million sales milestone payment and recorded royalty revenue of $16.2 million.

During 2021, we recorded royalty revenue of $22.2 million.

We are eligible to receive an additional $20.0 million in sales milestones and a low-single digit percent royalty on the sale of approved products.

Vir Biotechnology, Inc.

Sotrovimab, an antibody that targets the SARS-CoV-2 virus, has received an emergency use authorization from the FDA and temporary authorizations in multiple global markets for the treatment of mild-to-moderate COVID-19 in high-risk adults and pediatric patients.

In addition, Vir is evaluating VIR-7832 in a Phase 1b/2a trial of adults with mild-

to-moderate COVID-19.

In March 2020, we entered into an agreement in which we provided Vir a non-exclusive license to our Xtend technology to extend the half-life of novel antibodies, including sotrovimab, that Vir is investigating as potential treatments for patients with COVID-19.

Vir is responsible for all research, development, regulatory and commercial activities for COVID-19 antibodies, and we are eligible to receive royalties on the net sales of approved products in the mid-single digit percentage range.

During 2021, we recorded estimated royalty revenue of $52.2 million.

In August 2019, we entered into an agreement with Vir Biotechnology, Inc., in which we provided Vir a non-exclusive license to our Xtend technology for two targets in infectious disease.

We received an upfront payment, and we are eligible to receive total milestones of $155.0 million, including $5.0 million of development milestones, $30.0 million of regulatory milestones and $120.0 million of sales milestones.

We have received a total of $1.5 million in upfront and milestone payments, and we are eligible to receive additional milestones of $154.5 million, including $4.5 million of development milestones, $30.0 million of regulatory milestones and $120.0 million of sales milestones.

We are also eligible to receive royalties on the net sales in the low single digit percentage range.

Vir has advanced two programs under this agreement.

VIR-2482 is being evaluated in a Phase 1/2 study as a universal prophylactic for influenza A, and VIR-3434 is being evaluated in a Phase 1 study as a potential treatment for patients with hepatitis B virus infection.

In March 2020, we entered into a second agreement in which we provided Vir a non-exclusive license to our Xtend technology to extend the half-life of novel antibodies Vir is investigating as potential treatments or for patients with COVID-19.

percentage range.

Vir is currently conducting Phase 3 studies of VIR-7831 as a potential treatment for the treatment of COVID-19.

VIR-2482 is being evaluated in a Phase 1/2 study as a universal prophylactic for influenza A, and VIR-3434 is being evaluated in a Phase 2 combination study as a potential treatment for patients with hepatitis B virus infection.

Gilead Sciences, Inc.

In January 2020, we entered into an agreement with Gilead Sciences, Inc., in which we provided Gilead an exclusive license to our Cytotoxic Fc and Xtend Fc technologies for an initial identified antibody and options for up to three additional antibodies, all broadly neutralizing anti-HIV antibodies.

Gilead has exercised its options for all three additional antibodies.

In January 2020, we entered into an agreement with Gilead Sciences, Inc., in which we provided Gilead an exclusive license to our Cytotoxic Fc and Xtend Fc technologies for broadly neutralizing anti-HIV antibodies.

Gilead is responsible for all development and commercialization activities.

During 2020, we received upfront and option payments of $13.5 million, and for each of four antibodies, we are eligible to receive up to $67.0 million in milestones, which includes $10.0 million in development milestones, $27.0 million in regulatory milestones and $30.0 million in sales milestones.

For each licensed antibody, we are eligible to receive up to $67.0 million in milestones, which includes $10.0 million in development milestones, $27.0 million in regulatory milestones, and $30.0 million in sales milestones.

We are also eligible to receive royalties in the low-single digit percentage range on net sales of approved products.

Gilead has advanced antibodies, including elipovimab (GS-9722) and GS-9723, into clinical studies.

Bristol-Myers Squibb Company

In May 2021, we entered into an agreement with Bristol-Myers Squibb Company (BMS), in which we provided BMS a non-exclusive license to our Xtend Fc technology to extend the half-life of antibodies that specifically bind to SARS-CoV-2.

BMS is responsible for all research, development, regulatory and commercial activities.

We are eligible to receive royalties on net sales of approved products in the low-single digit percentage range.

BMS is evaluating the SARS-CoV-2 mAb Duo antibody combination therapy (BMS-986414 + BMS-986413) in the Phase 2/3 NIH ACTIV-2 trial in treating COVID-19 in outpatients.

Omeros Corporation

In August 2020, we entered into an agreement with Omeros Corporation, in which we provided Omeros a non-exclusive license to our Xtend Fc technology, an exclusive license to apply our Xtend Fc technology to an initial identified antibody and options to apply our Xtend Fc technology to three additional antibodies.

In August 2020, we entered into an agreement with Omeros Corporation, in which we provided Omeros a non-exclusive license to our Xtend Fc technology, an exclusive license to apply our Xtend Fc technology to an initial identified antibody, OMS906, and options to apply our Xtend Fc technology to three additional antibodies.

Omeros is responsible for all development and commercialization activities.

OMS906, a MASP-3 targeted antibody, is being evaluated in a Phase 1 study in patients with PNH and other alternative pathway disorders.

We received an upfront payment of $5.0 million, and for each product incorporating our Xtend Fc technology, we are eligible to receive up to $65.0 million in milestones, which includes $15.0 million in development milestones, $25.0 million in regulatory milestones and $25.0 million in sales milestones.

We are also eligible to receive royalties in the mid-single digit percentage range on net sales of approved products.

Viridian Therapeutics, Inc./MiRagen Therapeutics, Inc.

In December 2020, we entered into an agreement with MiRagen Therapeutics, Inc., in which we provided MiRagen a non-exclusive license to our Xtend Fc technology and an exclusive license to apply our Xtend Fc technology to antibodies targeting IGF-1R.

MiRagen subsequently changed its name to Viridian Therapeutics, Inc.

Viridian Therapeutics, Inc.

In December 2020, we entered into an agreement with Viridian Therapeutics, Inc., in which we provided Viridian a non-exclusive license to our Xtend Fc technology and an exclusive license to apply our Xtend Fc technology to antibodies targeting IGF-1R.

Viridian is responsible for all development and commercialization activities.

1 unchanged sentence

We are also eligible to receive royalties in the mid-single digit percentage range on net sales of approved products.

Catabasis Pharmaceuticals, Inc./Quellis Biosciences, Inc.

In December 2021, we entered into a second agreement with Viridian for a non-exclusive license to certain antibody libraries developed by us.

Under the agreement, Viridian received a one-year research license to review the antibodies and the right to select up to three antibodies for further development.

Viridian is responsible for all further development of the selected antibodies.

We received an upfront payment of 394,737 shares of Viridian common stock valued at $7.5 million and are eligible to receive development, regulatory and sales milestones in addition to royalties on net sales of approved products under the agreement.

Astria Therapeutics, Inc/Catabasis Pharmaceuticals, Inc./Quellis Biosciences, Inc.

In May 2018, we entered into an agreement with Quellis Biosciences, Inc., in which we provided Quellis a non-exclusive license to our Xtend Fc technology to apply to an identified antibody.

1 unchanged sentence

We received an equity interest in Quellis, and in January 2021, upon Quellis merging into Catabasis Pharmaceuticals, Inc., we received common and preferred shares of Catabasis stock in exchange for our equity in Quellis.

Catabasis subsequently changed its name to Astria Therapeutics, Inc.

We are eligible to receive up to $66.0 million in milestones, which include $6.0 million in development milestones, $30.0 million in regulatory milestones and $30.0 million in sales milestones.

1 unchanged sentence

Strategic Collaborations

We enter into strategic collaborations where we can create synergies between our partners' capabilities and assets and our own protein engineering capabilities, XmAb technologies and XmAb drug candidates.

We enter into strategic collaborations where we can create synergies between our partners’ capabilities and assets and our own protein engineering capabilities, Fc technologies and XmAb drug candidates.

Through these arrangements we seek to create new drug candidates, investigate novel combination therapies and potentially identify additional indications for our portfolio of XmAb drug candidates.

In November 2020, we entered into an agreement with MorphoSys AG to conduct clinical studies to investigate the combination of plamotamab and tafasitamab in combination with lenalidomide in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), first-line DLBCL, and relapsed or refractory follicular lymphoma (FL).

In November 2020, we entered into a strategic collaboration with MorphoSys AG and Incyte to conduct clinical studies to investigate the chemo-therapy free combination of plamotamab and tafasitamab in combination with lenalidomide in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), first-line DLBCL, and relapsed or refractory follicular lymphoma (FL).

MorphoSys and Incyte Corporation will provide tafasitamab for the studies, which Xencor will sponsor and fund.

We plan to initiate a Phase 1/2 study evaluating the combination in patients with relapsed or refractory DLBCL in the second half of 2021.

In July 2020, we entered into an agreement with Atreca, Inc., to research, develop and commercialize novel CD3 bispecific antibodies as potential therapeutics in oncology.

7 unchanged sentences

We own all rights to the programs and results generated from these studies.

In December 2021, we extended the agreement for an additional year at the same level of committed funding.

In December 2020, we entered into a second agreement with MD Anderson to develop novel CD3 bispecific antibody therapeutics for the potential treatment of patients with cancer.

6 unchanged sentences

We continue to advance these candidates as additional options for clinical development by us or as out-licensing opportunities.

We also from time to time in-license antibody technologies and compounds from other companies which we believe may allow us to create potential product candidates by incorporating our XmAb technology.

These licenses may require us to pay upfront fees, development, and commercial milestone payments, and if commercial products are approved, royalties on net sales.

4 unchanged sentences

As of December 31, 2021, we had 254 full-time employees, representing a 26% increase in our employee workforce as compared to December 31, 2020.

Of these, 156 were engaged in research and development

activities, and 46 are engaged in business development, information systems, facilities, human resources or administrative support.

Of these, 205 were engaged in research and development activities, and 49 were engaged in business development, information systems, facilities, human resources, or administrative support.

Of these employees, 65 hold Ph.D.

3 unchanged sentences

We are an equal opportunity employer and maintain policies that prohibit unlawful discrimination based on race, color, religion, gender, sexual orientation, gender identity/expression, national origin/ancestry, age, disability, marital and veteran status.

We are proud to employ a diverse workforce that, as December 31, 2020, was 53% non-white and 55% women.

We are proud to employ a diverse workforce that, as of December 31, 2021, was 57% non-white and 56% women.

In addition, as of December 31, 2021, women made up 22% of our senior leadership team.

We strive to build and nurture a culture where all employees feel empowered to be their authentic selves.

We seek to provide human capital policies that provide for the health, safety and welfare of our employees as well as professional development and training.

In 2020 in connection with the ongoing pandemic we implemented the following policies:

● Instituted a remote work mandate for all non-laboratory staff and provided technical support and training to enable employees to continue to perform their responsibilities while working remotely;

● Implemented onsite safety procedures for all laboratory staff which includes mandatory weekly onsite SARS-CoV-2 virus testing for all laboratory employees and their household members, reimbursement of 100% of medical insurance costs for all onsite employees, and fully paid time off for any employee that missed time due to the COVID-19 virus including for the care of family members;

● Provided additional compensation for onsite employees and provided additional days off for all employees.

We provide compensation packages designed to attract and retain high-quality employees, and all of our employees are eligible for cash bonuses and grants of equity awards.

We regularly evaluate our compensation programs with an independent compensation consultant and utilize industry benchmarking in an effort to ensure they are competitive compared to similar biotechnology and biopharmaceutical companies with which we compete for talent and that they are fair and equitable across our workforce with respect to gender, race, and other personal characteristics.

In addition, we provide a variety of programs and services to help employees meet and balance their needs at work, at home and in life, including an attractive mix of healthcare, insurance, and other benefit plans.

We deliver a benefits program that is designed to keep our employees and their families healthy, which includes not only medical, dental and vision benefits, but also dependent care, mental health, and other wellness benefits.

● We also value career development for all employees, and we provide reimbursement and time for employees to attend professional development courses ranging from technical training, competency-based workshops and leadership development programs facilitated by external partners who are experts in their respective fields.

We seek to provide human capital and employee health and safety policies that provide for the health, safety, and welfare of our employees.

We continue practices that address the COVID-19 pandemic consistent with government guidelines to mitigate and prevent the spread of disease, such as masking, social distancing, contact tracing, and encouraging vaccinations.

In 2021, in connection with the ongoing pandemic we continued the following practices:

● Provided a remote or hybrid work option for all non-laboratory staff with technical support, training, and equipment to enable employees to continue to perform their responsibilities while working remotely;

● Conducted safety procedures for all onsite staff which includes mandatory weekly onsite SARS-CoV-2 virus testing for all employees and their household members, reimbursement of 100% of medical insurance costs for onsite employees, and fully paid time off for any employee that missed time due to the COVID-19 virus including for the care of family members.

Compensation, Benefits, and Development

We provide compensation packages designed to attract, retain, and motivate high-quality employees, and all of our employees are eligible for cash bonuses and grants of equity awards.

We regularly evaluate our compensation programs with an independent compensation consultant and utilize industry benchmarking in an effort to ensure they are

competitive compared to similar biotechnology and biopharmaceutical companies with which we compete for talent and that they are fair and equitable across our workforce with respect to gender, race, and other personal characteristics.

All employees are eligible to participate in the Employee Stock Purchase Plan where they can purchase shares of Xencor common stock at a discounted price.

This plan, and our other equity compensation plans, assists us in building long-term relationships with our employees and aligns the interest of employees with stockholders.

We also deliver a benefits program that is designed to keep our employees and their families healthy, which includes not only medical, dental and vision benefits, but also dependent care, mental health, and other wellness benefits.

In addition, we provide a variety of programs and services to help employees meet and balance their needs at work, at home and in life.

We value career development for all employees, and we provide reimbursement and time for employees to attend professional development courses ranging from technical training, competency-based workshops, and leadership development programs.

Direct managers also take an active role in identifying individualized development plans to assist their employees in realizing their full potential and creating opportunities for promotions and added responsibilities that enhance the engagement and retention of our workforce.

Market Opportunity

Our drug candidates that use the XmAb bispecific Fc domain, including plamotamab, XmAb717, vibecotamab, tidutamab, XmAb841, XmAb104 and XmAb306 :

Our drug candidates that use the XmAb bispecific Fc domain, including plamotamab, vudalimab , tidutamab, XmAb841, XmAb104, XmAb306, and XmAb564 :

We are developing our bispecific antibody and cytokine candidates to treat cancer.

2 unchanged sentences

The National Institutes of Health (NIH) estimated that based on growth and aging of the U.S.

population, medical expenditures for cancer in the year 2020 were projected to reach at least $158.0 billion (in 2010 dollars).

population, medical expenditures for cancer in the year 2030 are projected to reach at least $245.6 billion.

Intellectual Property

17 unchanged sentences

Patent Expiry

Obexelimab (XmAb5871)

XmAb717, XmAb841, XmAb104

Vudalimab, XmAb841, XmAb104

Partnered Products

2 unchanged sentences

AIMab7195 (XmAb7195)

Obexelimab (XmAb5871)

The Hatch-Waxman Act permits a patent term extension for FDA-approved drugs, including biological products, of up to five years beyond the expiration of the patent.

3 unchanged sentences

In the future, if and when our pharmaceutical product candidates receive FDA approval, we expect to apply for patent term extensions on patents covering those products.

We intend to seek patent term extensions to any of our issued patents in any jurisdiction where these are available, however there is no guarantee that the applicable authorities, including the FDA in the United States, will agree with our assessment of whether such extensions should be granted, and even if granted, the length of such extensions.

We intend to seek patent term extensions to any of our issued patents in any jurisdiction where these are available;

however, there is no guarantee that the applicable authorities, including the FDA in the United States, will agree with our assessment of whether such extensions should be granted, and even if granted, the length of such extensions.

The Patient Protection and Affordable Care Act, as amended by the Healthcare and Education Affordability Reconciliation Act (collectively the ACA) created a regulatory scheme authorizing the FDA to approve biosimilars via an abbreviated licensure pathway.

4 unchanged sentences

The "biosimilar"

application must include specific information demonstrating biosimilarity based on data derived from:

application must include specific information demonstrating bio similarity based on data derived from:

(1) analytical studies, (2) animal studies, and (3) a clinical study or studies that are sufficient to demonstrate safety, purity, and potency in one or more appropriate conditions of use for which the reference product is licensed, except that FDA may waive some of these requirements for a given application.

7 unchanged sentences

Further, we seek trademark protection in the United States and in certain other jurisdictions where available and when we deem appropriate.

We have obtained registrations for the Xencor trademark, as well as certain other trademarks, which we use in connection with our pharmaceutical research and development services and our clinical-stage products, including XmAb, PDA, Protein Design Automation, Proteins By Design and Antibodies By Design.

We currently have registrations for Xencor and PDA in the United States, Australia, Canada, the European Community, and Japan, for Protein Design Automation in the United States, Australia, Canada, and the European Community, and for XmAb in the United States, Australia, Canada, the European Community and Japan.

4 unchanged sentences

We believe that this allows us to accelerate the drug development process by not relying on third parties for all of our manufacturing needs.

We have adopted a manufacturing strategy of contracting with third parties in accordance with current good manufacturing practices (cGMPs) for the manufacture of drug substance and product, including our pipeline of bispecific antibody and cytokine development candidates and also our obexelimab development candidate.

We have used third party manufacturers for all our bispecific antibody and cytokine candidates which include:

vibecotamab, plamotamab, tidutamab, XmAb717, XmAb841, XmAb104, XmAb306, and XmAb564.

plamotamab, tidutamab, vudalimab, XmAb841, XmAb104, XmAb306, XmAb564, and XmAb819.

Additional contract manufacturers are used to fill, label, package and distribute investigational drug products.

This allows us to maintain a more flexible infrastructure while focusing our expertise on developing our products.

Obexelimab is produced by mammalian cell culture of a Chinese hamster ovary cell line that expresses the antibody, followed by multiple purification and filtration steps typical of those used for monoclonal antibodies.

We do not have any long-term manufacturing agreements in place and will ultimately depend on contract manufacturers for the manufacture of our products for commercial sale, as well as for process development.

We have successfully completed clinical trials with subcutaneous formulations for obexelimab which have been manufactured with third party contract manufacturers.

In February 2020, we entered into a License, Development and Commercialization Agreement for XmAb7195 (Aimmune Agreement) with Aimmune Therapeutics, Inc.

Under the Aimmune Agreement, Aimmune will assume all future manufacturing of XmAb7195.

KBI Biopharma, Inc.

1 unchanged sentence

We have engaged KBI under the KBI Agreement for process development, clinical scale-up, analytical method development, formulation development, and other services related to drug substance and drug product for our bispecific antibody and cytokine development candidates:

vibecotamab, plamotamab, tidutamab, XmAb717, XmAb841, XmAb104, XmAb306, and XmAb564 in accordance with cGMP regulations.

plamotamab, tidutamab, vudalimab, XmAb841, XmAb104, XmAb306, and XmAb564 in accordance with cGMP regulations.

For each bispecific program, we have entered into a separate agreement with the terms and conditions of services and payment.

7 unchanged sentences

The royalty is less than 1%.

Selexis has manufactured cell lines for all our bispecific antibody and cytokine drug candidates, and we currently have commercial licenses to the Selexis cell line for the following bispecific antibody and cytokine candidates:

vibecotamab, plamotamab, tidutamab, XmAb717, XmAb841, XmAb104, XmAb306 and XmAb564.

Selexis has manufactured cell lines for certain of our bispecific antibody and cytokine drug candidates, and we currently have rights to obtain commercial licenses to the Selexis cell line for the following bispecific antibody and cytokine candidates:

plamotamab, tidutamab, vudalimab, XmAb841, XmAb104, XmAb306, XmAb564, and XmAb819.

License Agreements with BIO-TECHNE

3 unchanged sentences

The royalty is less than 1%.

We entered into a second agreement with BIO-TECHNE effective February 2018 for a non-exclusive license to a certain recombinant monoclonal antibody reactive with human programmed death protein, PD-1 antibody.

We entered into a second agreement with BIO-TECHNE effective February 2018 for a non-exclusive license to a certain recombinant monoclonal antibody reactive with human programmed death protein, PD-1.

We expect to use this protein in certain of our oncology drug candidates.

4 unchanged sentences

Under the terms of the Patheon Agreement, any of the affiliates within the global network of service sites in Thermo Fisher Scientific Inc.’s Pharma Services Group may perform clinical manufacturing and development services for us in accordance with cGMP regulations.

The Patheon Agreement includes a statement of work for Patheon to provide process transfer, process development and cGMP manufacturing to support our obexelimab program.

The Patheon Agreement may be terminated by either party for a breach or default that is not remedied within 30 days, or such other time period as may be reasonably necessary to remedy such breach after receiving notice of the breach from the non-breaching party or if the other party is subject to an insolvency event.

1 unchanged sentence

Patheon has the unilateral right to terminate the Patheon Agreement if we request to reschedule work beyond 120 days, the project work is not progressing according to our expectations and we cannot agree on appropriate changes, after six months of inactivity on a project at our request or if Patheon determines it is unable to perform its obligations in a safe and effective way in compliance with applicable regulatory requirements.

Patheon is currently conducting process transfer, process development and cGMP manufacturing for our obexelimab program and process development and cGMP manufacturing for our XmAb819 program.

Patheon is currently conducting process transfer, process development and cGMP manufacturing for our XmAb819 program.

Master Services Agreement with WuXi Biologics (Hong Kong) Limited

In February 2021, we entered into a Master Services Agreement (WuXi Agreement) with WuXi Biologics (Hong Kong) Limited (WuXi).

Under the terms of the WuXi Agreement, WuXi and its affiliates will perform manufacturing, analytical, development and other services for Xencor in accordance with applicable regulations.

The WuXi Agreement includes customary rights to replacement of non-conforming products.

The WuXi Agreement may be terminated by either party for a breach by the other party that is not remedied within 45 days (or 10 days for a non-payment breach), or if the other party is subject to an insolvency event.

We have the unilateral right to terminate the WuXi Agreement upon 90 days’ prior written notice to WuXi for any reason, subject to applicable cancellation fees.

WuXi has the unilateral right to terminate the WuXi Agreement only if the services cannot be performed due to technical difficulties or the performance of the services is not permitted under applicable law.

WuXi is currently conducting process transfer, process development and cGMP manufacturing for our XmAb808 (B7-H3 x CD28) and our IL-12 programs.

Master Clinical Services Agreement with ICON Clinical Research Limited

In April 2016, we entered into a Master Clinical Services Agreement (ICON Agreement) with ICON Clinical Research Limited (ICON).

Under the terms of the ICON Agreement, ICON and its affiliates will perform clinical trial services (including site selection, study design, site monitoring, management and training, and patient selection) for Xencor in accordance with applicable regulations.

The ICON Agreement may be terminated by either party for a breach by the other party that is not remedied within 30 days, or if the other party is subject to an insolvency event.

Each party may terminate the ICON Agreement upon 30 days’ prior written notice to the other party for any reason, however such termination would not affect any ongoing project under the ICON Agreement.

We may unilaterally terminate any project under the ICON Agreement upon 30 days’ prior written notice to ICON for any reason, subject to applicable termination fees.

ICON is currently providing services to us in connection with each ongoing Xencor-sponsored clinical trial.

We compete in an industry that is characterized by rapidly advancing technologies, intense competition, and a strong emphasis on proprietary products.

9 unchanged sentences

Regeneron Pharmaceuticals, Inc.;

Roche Holding AG;

and Zymeworks Inc.

and Roche Holding AG.

We are developing bispecific antibody drug candidates engineered to direct cytotoxic T cell killing of tumor cells, by engaging the CD3 receptor on T cells and an antigen on tumor cells.

5 unchanged sentences

Other antibodies, antibody drug candidates and cell therapies are in development or approved to treat patients with non-Hodgkin lymphomas.

Regarding vibecotamab, other companies developing CD3 bispecific antibodies directed to CD123, an antigen expressed on myeloid tumors, include Aptevo Therapeutics Inc.

and Macrogenics, Inc.

We are also developing several bispecific antibody drug candidates engineered to selectively engage the immune system in order to treat patients with cancer, such as XmAb717, XmAb841 and XmAb104.

We are also developing several bispecific antibody drug candidates engineered to selectively engage the immune system in order to treat patients with cancer, such as vudalimab, XmAb841 and XmAb104.

Immuno-oncology is a competitive field within the biotechnology and pharmaceutical industries, and most large pharmaceutical companies are developing drug candidates, have marketed medicines in this space, or both:

5 unchanged sentences

and Sanofi S.A.

While tuning the binding affinities plays a crucial role in designing the mechanism of action for this class of bispecific antibody, smaller companies advancing clinical programs that, like XmAb717, dually target the immune checkpoint receptors PD-1 and CTLA-4 include Akeso, Inc.

While tuning the binding affinities plays a crucial role in designing the mechanism of action for this class of bispecific antibody, smaller companies advancing clinical programs that, like vudalimab, dually target the immune checkpoint receptors PD-1 and CTLA-4 include Akeso, Inc.

and Macrogenics, Inc.

7 unchanged sentences

Medicenna Therapeutics Corp.;

Merck & Co., Inc.;

Nektar Therapeutics, Inc.;

Neoleukin Therapeutics, Inc.;

Pandion Therapeutics, Inc.;

Roche Holding AG;

11 unchanged sentences

and other countries.

Regulation by government authorities is a significant factor in the development, manufacture, distribution and ongoing research activities.

Regulation by government authorities is a significant factor in development, manufacture, distribution and ongoing research activities.

All our products in development will require regulatory approval by government agencies prior to commercialization.

5 unchanged sentences

Our product candidates are subject to regulation by the FDA as a biologic.

Biologics require the submission of a BLA to the FDA and approval of the BLA by the FDA before marketing in the United States.

Biologics require the submission of a Biologics License Application (BLA) to the FDA and approval of the BLA by the FDA before marketing in the United States.

The process of obtaining regulatory approvals for commercial sale and distribution and the subsequent compliance with applicable federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources.

46 unchanged sentences

Depending upon the timing, duration and specifics of the FDA approval of any of our biologic product candidates, we may apply for limited patent term extension under the Drug Price Competition and Patent Term Restoration Act of 1984, commonly referred to as the Hatch-Waxman Amendments.

The Hatch-Waxman Amendments permit a patent restoration term of up to five years for one patent per product as compensation for patent term lost during product development and the FDA regulatory review process of that product.

The Hatch-Waxman Amendments permit a patent restoration term of up to five years for one patent per product as compensation for patent term lost during

product development and the FDA regulatory review process of that product.

Patent and Trademark Office, in consultation with the FDA, reviews and approves the application for any patent term extension or restoration.

25 unchanged sentences

Our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to reports filed or furnished pursuant to Section 13(a) and 15(d) of the Securities Exchange Act of 1934, as amended, are available free of charge on the Investor Relations portion of our web site at www.xencor.com as soon as reasonably practical after we electronically file such material with, or furnish it to, the Securities and Exchange Commission (SEC).

The SEC maintains an internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC and state the address of that site (www.sec.gov).

The SEC maintains an internet site at www.sec.gov that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC.

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