Arcus Biosciences, Inc. (RCUS) Business

Item 1. Business

Company Overview

We are a late clinical-stage biopharmaceutical company focused on developing differentiated molecules for patients with cancer and inflammatory and autoimmune diseases. Our most advanced molecules are in Phase 3 registrational studies for various cancer indications and we expect our next wave of clinical-stage molecules to come from our inflammation and autoimmune disease programs. Our vision is to leverage our internal small-molecule discovery capabilities to create, develop and commercialize highly differentiated therapies that can have a meaningful impact on patients.

The chart below summarizes our current clinical and late pre-clinical stage portfolio:

* Taiho holds exclusive licenses in Japan and certain other Asian countries, excluding China, for casdatifan (the “Taiho Territory”).

† Gilead and Arcus co-develop globally and share co-promotion rights in the U.S. for domvanalimab and quemliclustat. Gilead holds commercialization rights outside of the U.S. subject to Taiho’s rights for the Taiho Territory.

‡ Gilead has certain option rights as further described under “Licenses and Collaborations”.

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Oncology Programs

Casdatifan (HIF-2α Inhibitor)

Casdatifan is our oral, small-molecule inhibitor of HIF-2α, a target that has been commercially validated by the approval of Merck & Co., Inc's ("Merck") HIF-2α inhibitor belzutifan. HIF-2α is a protein that is involved in sensing oxygen availability in multiple organs. In certain tumors, particularly clear cell renal cell carcinoma ("ccRCC"), HIF-2⍺ activity is highly dysregulated as a result of genetic abnormalities. This creates a situation of pseudohypoxia and the abnormal increase in HIF-2⍺-mediated expression of a wide array of proteins involved in cancer cell proliferation, survival, treatment resistance and angiogenesis.

We designed casdatifan to have superior pharmacokinetic and pharmacodynamic properties relative to belzutifan, with the goal of achieving greater efficacy in ccRCC patients. The ability for casdatifan to achieve greater efficacy has now been demonstrated in a clinical study in patients. Specifically, in our Phase 1/1b ARC-20 study, which evaluated casdatifan monotherapy in approximately 120 late-line ccRCC patients, casdatifan achieved improvement on every efficacy measure including rate of primary progressive disease, overall response rate ("ORR") and progression-free survival ("PFS"), relative to data reported for belzutifan in a similar patient population.

Our goal for casdatifan is to leverage the potential best-in-class efficacy profile and maximize the opportunity for casdatifan by developing this molecule across multiple settings and with optimal combination partners. ARC-20 is designed to generate safety and proof-of-concept clinical data to support and inform our registrational studies for casdatifan. To date, we have completed enrollment of eight cohorts, including four monotherapy cohorts in late-line ccRCC, a cohort evaluating casdatifan plus cabozantinib in ccRCC patients previously treated with immunotherapy and three cohorts evaluating casdatifan in early line settings of ccRCC.

The initial registrational studies for casdatifan will focus on combination approaches that build on top of standard of care therapies, while also exploring opportunities for casdatifan to become a foundational standard of care.

Our first Phase 3 clinical trial, PEAK-1, is evaluating casdatifan and cabozantinib in ccRCC patients that have received prior immunotherapy, which we believe has a potential global peak sales opportunity of greater than $2 billion. This study has a primary endpoint of PFS and is currently enrolling.

Our second Phase 3 clinical trial is expected to evaluate casdatifan in a Tyrosine Kinase Inhibitor ("TKI")-free regimen for the treatment of first-line ccRCC, which we believe represents a potential global peak sales opportunity of greater than $3 billion. This strategy capitalizes on the strong desire by clinicians and patients to avoid TKIs and their associated toxicities in the first-line setting. This Phase 3 study, which we are targeting initiation of by the end of 2026, will be informed by emerging data from the following ongoing cohorts and studies:

•A cohort in ARC-20 evaluating casdatifan plus zimberelimab, our anti-PD-1 antibody, in first-line ccRCC. Casdatifan plus anti-PD-1 is likely to serve as the backbone of our front line TKI-free strategy. This cohort has completed enrollment.

•We are enrolling a cohort in ARC-20 to evaluate casdatifan in combination with ipilimumab and zimberelimab in first-line ccRCC. Ipilimumab, an anti-CTLA-4 antibody, plus nivolumab, an anti-PD-1 antibody, are approved as a standard of care therapy in first-line ccRCC.

•eVOLVE-RCC02 is a Phase 1b/3 clinical trial operationalized by AstraZeneca plc ("AstraZeneca") evaluating casdatifan and volrustomig (AstraZeneca’s anti-PD-1 / anti-CTLA-4 bispecific antibody) in first-line ccRCC. A decision was made to temporarily pause recruitment, after observing certain immune-mediated AEs. We and AstraZeneca are evaluating emerging data which will inform next steps for the study.

Quemliclustat (CD73 Inhibitor)

Under conditions of cellular damage or cell death, such as in response to certain chemotherapies, large amounts of adenosine triphosphate ("ATP") are released into the extracellular environment, where it is converted into adenosine monophosphate by the enzyme CD39 and then into adenosine by the enzyme CD73. The generation of large amounts of extracellular adenosine results in an immunosuppressive response that counteracts some of the potentially beneficial effects of chemotherapy.

Quemliclustat is a small-molecule inhibitor that targets the CD73 enzyme that plays a critical role in the last step in the conversion of extracellular ATP into adenosine. Further, we believe targeting CD73 could be a highly effective approach to inhibiting adenosine-mediated immune suppression by suppressing adenosine generation.

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We believe quemliclustat was the first small-molecule CD73 inhibitor to enter clinical development. We believe that a small-molecule approach to CD73 inhibition could offer several advantages over antibody approaches, including more complete inhibition of CD73 enzymatic activity, deeper tumor penetration, and potential for both intravenous and oral delivery.

We are evaluating quemliclustat in the following study:

•PRISM-1 is a Phase 3 study in metastatic pancreatic cancer evaluating quemliclustat with gemcitabine and nab-paclitaxel (the standard-of-care chemotherapies used for advanced pancreatic cancer) against gemcitabine and nab-paclitaxel. This study completed enrollment in September 2025, less than 12 months after study initiation, and we expect results from this study in the first half of 2027.

Domvanalimab (Anti-TIGIT Antibody)

TIGIT is believed to play an important role in suppressing the immune response to cancer. The primary ligand for TIGIT (T cell immunoreceptor with Ig and ITIM domains) is CD155, a protein that plays both inhibitory and stimulatory roles in regulating the activity of effector immune cells, such as T and natural killer ("NK") cells. TIGIT is an inhibitory receptor highly expressed on T cells displaying an exhausted phenotype, tumor-infiltrating Treg, and NK cells. The ligands for TIGIT, including CD155, are broadly expressed on multiple cell types in the tumor microenvironment, including cancer cells. CD155 binding to TIGIT results in inhibition of immune cells.

As T cells are important in the immune response, domvanalimab was engineered to lack Fc-receptor binding in order to minimize the risk of depleting such cells.

In December 2025, we announced that our Phase 3 STAR-221 clinical trial, which evaluated domvanalimab in combination with zimberelimab and chemotherapy in first-line metastatic GI cancers, is being discontinued due to futility. Based on this result, we are also discontinuing our Phase 2 EDGE-Gastric study. The following Phase 3 studies for domvanalimab are still ongoing:

•STAR-121 is a Phase 3 study evaluating domvanalimab in combination with zimberelimab and chemotherapy versus pembrolizumab and chemotherapy in first-line non-small cell lung cancer ("NSCLC"). A futility analysis is expected to be conducted for this study in the first quarter of 2026.

•PACIFIC-8 is a Phase 3 study evaluating domvanalimab in combination with durvalumab following chemoradiation in Stage 3 NSCLC, a setting in which durvalumab is already approved.

Zimberelimab (Anti-PD-1 Antibody)

Zimberelimab has been evaluated in clinical trials, either alone or in combination with other agents, in over 2600 patients across several studies conducted by us. The clinical results to date have shown that zimberelimab has an efficacy and safety profile consistent with anti-PD-1 mechanism of action.

We are currently evaluating zimberelimab in combination with casdatifan for the treatment of first-line ccRCC in our Phase 1/1b ARC-20 study. We are also initiating two additional cohorts in this study to evaluate casdatifan in combination with zimberelimab and ipilimumab in first-line ccRCC utilizing two different dosing regimens.

Inflammation Programs

We have active discovery efforts focused on the creation of development candidates aimed at regulating excessive immune activity in the context of various types of inflammation and autoimmune diseases. These discovery efforts leverage the small molecule-focused infrastructure and capabilities that led to our pipeline of oncology development candidates, including casdatifan. Our goal is to develop best-in-class, oral, small-molecule drugs to displace injectable biologics for the treatment of the most common inflammatory and autoimmune diseases.

Our inflammation portfolio is currently comprised of five research and preclinical programs directed to MRGPRX2, TNF, CCR6, CD89 and CD40 ligand, and we expect to advance our first development candidate from these programs into the clinic in 2026.

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MRGPRX2 Antagonist Program

Our most advanced inflammation program has identified an orally active, highly potent and selective, small-molecule inhibitor of MRGRX2 that we believe has the potential to be best-in-class. In recent years, the MRGPRX2 receptor has been identified as a major regulator of mast cell function, playing an important role in the interplay between inflammation and pain sensation in certain dermal atopic conditions, such as chronic urticaria and atopic dermatitis. Due to its potency, our development candidate is expected to achieve similar biological activity as the most advanced MRGPRX2 inhibitor in clinical development, but at much lower plasma levels, thereby avoiding the toxicities that have been observed with competitor molecules at higher drug exposures.

Initially, we plan to develop our MRGPRX2 inhibitor in chronic spontaneous urticaria ("CSU"), an inflammatory disease characterized by hives and pruritus. We believe that inhibiting MRGPRX2 may offer several advantages over other approaches for the treatment of CSU, including the ability to treat patients whose disease is not primarily driven by immunoglobulin E ("IgE"), oral administration, greater specificity for mast cells, and fewer side effects such as neutropenia and hair depigmentation. We also believe that MRGPRX2 inhibition has the potential to treat other inflammatory disorders, such as atopic dermatitis, in which mast cells play key pathological roles. Both CSU and atopic dermatitis represent multi-billion dollar sales opportunities.

We expect to initiate our first study for our MRGPRX2 inhibitor in 2026 in healthy volunteers to identify the optimal dosing for our molecule. Following these studies in healthy volunteers, we expect to initiate a proof-of-concept study in subjects with chronic inducible urticaria.

TNF Inhibitor Program

Our TNF program is focused on the design of orally active, small molecules that selectively block the activity of TNF on its pro-inflammation receptor, known as TNFR1, while sparing the ability of TNF to signal via its other receptor ("TNFR2"), which is generally understood to be important for orchestrating anti-inflammatory processes and tissue repair. The value proposition for this approach is the ability to replace the injectable anti-TNF molecules, which have been considered the standard of care for many inflammatory and autoimmune diseases for many years, with a pill and a more selective agent that may not suffer from the undesirable consequences of TNFR2 blockade. We believe there is currently only one other small-molecule TNF inhibitor in clinical development, demonstrating the difficulty of developing highly potent and selective small molecules against this target.

We expect to identify our lead development candidate for this program in early 2026 and to file an IND for this molecule in late 2026 or early 2027.

Commercialization Plans

We currently own all of the commercial rights to casdatifan, with the exception of rights in Japan and certain other Asian countries (excluding China) which were optioned from us by Taiho Pharmaceutical Co., Ltd ("Taiho"). If we receive positive data from a registrational Phase 3 study for casdatifan, we expect to build the necessary infrastructure and sales, marketing and commercial capabilities to commercialize this program in the U.S. Outside the U.S., we could commercialize casdatifan on our own in certain regions, or with potential partners.

With respect to quemliclustat, domvanalimab and zimberelimab and subject to timely exercise of Gilead's and Taiho's respective option rights to other molecules in our pipeline, as discussed below, Gilead has certain commercialization rights under the Gilead Collaboration Agreement, and Taiho has commercial rights in Japan and certain other Asian countries based on the Option and License Agreement that we entered into with Taiho (as amended, the "Taiho Agreement"). In the U.S., we have an option to co-promote with Gilead, which we have elected for domvanalimab and zimberelimab, and expect to elect for quemliclustat.

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Licenses and Collaborations

Gilead Collaboration

Clinical Programs

Under the Gilead Collaboration Agreement, Gilead has exclusive licenses to develop and commercialize our anti-TIGIT program (including domvanalimab), anti-PD-1 program (including zimberelimab) and CD73 program (including quemliclustat) in certain markets. Gilead also has time-limited exclusive options to develop and commercialize (i) any of our clinical programs existing at the time of entering into the Gilead Collaboration Agreement and (ii) any programs that enter clinical development during the 10-year collaboration term. Gilead's continued option rights are contingent upon Gilead making $100 million continuation payments on each anniversary of the agreement in 2026 and 2028. Gilead's options expire, on a program-by-program basis, after a prescribed period, following the achievement of a clinical development milestone in such program and our delivery to Gilead of the requisite data package. Gilead may exercise its option to additional programs at any time prior to the expiration of the option and upon payment of an option fee of $150 million per program.

For each program that Gilead has exercised its option, both companies will co-develop and equally share global development costs, subject to certain opt-out rights that we have, caps on our spending and related subsequent adjustments, and certain other exceptions.

For each optioned program, provided we have not exercised our opt-out rights (if applicable), we have an option to co-promote in the U.S. with equal sharing of related profits and losses. Gilead has the right to exclusively commercialize any optioned programs outside of the U.S., subject to the rights of our existing partners to any territories, and Gilead will pay to us tiered royalties as a percentage of revenues ranging from the high teens to the low twenties. Further, with respect to domvanalimab, we remain eligible to receive up to $500 million in milestone payments.

Preclinical Programs

Under the Gilead Collaboration Agreement, Gilead has also received options to two oncology research programs (the "Oncology Research Programs") and two jointly selected research programs that target inflammatory diseases (the "Inflammation Research Programs"). We will lead discovery and early development activities for all Oncology Research Programs and Inflammation Research Programs.

With respect to the Oncology Research Programs, Gilead has the right to exercise its option, on a program-by-program basis, upon our completion of certain IND-enabling activities for an option payment of $60 million. If the option is exercised by Gilead at this stage, the collaboration terms for optioned programs will be applicable to each research program except, with respect to commercialization outside of the U.S., Gilead would pay us tiered royalties as a percentage of revenues ranging from high single digits to low double digits. If Gilead declines to exercise its option at this stage, Gilead maintains an option, on a program-by-program basis, which must be exercised prior to the expiration of a prescribed period following the achievement of a clinical development milestone in such program and our delivery to Gilead of the requisite data package. If the option is exercised by Gilead at this later clinical stage for an option payment of $150 million, the collaboration terms for optioned programs will be applicable to the joint development program including that, with respect to commercialization outside of the U.S., Gilead would pay us tiered royalties as a percentage of revenues ranging from the high-teens to the low twenties.

With respect to the Inflammation Research Programs, Gilead will have an option to license each program at two separate prespecified time points, either (i) exercise its option upon our completion of certain IND-enabling activities for an option payment of $45 million or (ii) extend its option and exercise it following the achievement of a clinical development milestone for an option payment of $150 million. If Gilead exercises its option at the earlier time point, we would be eligible to receive up to $375 million in regulatory and commercial milestone payments as well as tiered royalties for each optioned program. For any other Inflammation Research Program option exercised by Gilead, the parties would have rights to co-develop and share global development costs and to co-promote and share profits in the U.S. for that program.

Common Stock Purchase Agreement and Investor Rights Agreement

In connection with our entry into the Gilead Collaboration Agreement, we and Gilead entered into a Common Stock Purchase Agreement (as amended, the "Stock Purchase Agreement"), which expired in July 2025, and Investor Rights Agreement (as amended, the "Investor Rights Agreement"). We refer to the Gilead Collaboration Agreement, Stock Purchase Agreement and Investor Rights Agreement as the "Gilead Agreements". The Investor Rights Agreement provides Gilead with the right to designate three individuals, which they have exercised, to be appointed to our board of directors.

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Taiho License

In 2017, we entered into the Taiho Agreement pursuant to which Taiho obtained an exclusive option to in-license development and commercialization rights to programs for which IND-enabling studies had begun during a five-year term. These rights are geographically limited to Japan and certain other Asian countries (excluding China) (the "Taiho Territory"). To date, Taiho has exercised its option to our HIF-2α inhibitor program (including casdatifan), anti-TIGIT program (including domvanalimab), anti-PD-1 program (including zimberelimab), CD73 program (including quemliclustat) and adenosine receptor antagonist program (including etrumadenant). The five-year term expired in September 2022 and Taiho retains option rights to our CD39 program (including AB598). Taiho’s option to this program expires after a prescribed period following the achievement of a clinical development milestone in such program and our delivery to Taiho of the requisite data package.

For each Taiho optioned program, Taiho is obligated to pay to us (i) an option exercise payment for each program that is between $3 million to $15 million, (ii) clinical, regulatory and commercialization milestones of up to $275 million except for casdatifan (the HIF-2α program) for which we may receive up to $317 million, and (iii) royalties on net sales in Taiho’s territories ranging from high single digits to mid-teens. Royalties will be payable on a licensed product-by-licensed product and country-by-country basis during the period of time commencing on the first commercial sale of a licensed product in a country and ending upon the later of: (a) ten (10) years from the date of first commercial sale of such licensed product in such country; and (b) expiration of the last-to-expire valid claim of our patents covering the manufacture, use or sale or exploitation of such licensed product in such country. Taiho is also responsible for the development and commercialization of licensed products in the Taiho Territory except for casdatifan where we are responsible for global development and Taiho is responsible for commercialization in the Taiho Territory.

WuXi Biologics License - anti-PD-1

Our PD-1 license agreement (the "WuXi PD-1 Agreement") with WuXi Biologics Ireland Limited ("WuXi Biologics"), which we entered into in 2017 as subsequently amended, provides us with an exclusive license to (i) develop, use and manufacture products that include an anti-PD-1 antibody, including zimberelimab, throughout the world and (ii) commercialize any such products, throughout the world except in Greater China. Pursuant to the terms of the WuXi PD-1 Agreement, we may incur future clinical and regulatory milestone payments, commercialization milestone payments up to $375 million, and royalty payments that range from high single-digits to low teens of net sales beginning on the first commercial sale and ending on the later of (i) ten (10) years following such first commercial sale and (ii) the expiry of all patents that may subsequently be issued or granted that cover the product in such country, hereafter referred to as the royalty term.

Under the WuXi PD-1 Agreement, we are obligated to appoint WuXi Biologics as our exclusive manufacturer of the drug substance for such licensed products for a specified period of time subject to certain exceptions. Our sublicensees, however, may manufacture, at any time, certain portions of their requirements for such product subject to certain conditions. We made certain covenants not to commercialize any anti-PD-1 antibody licensed or obtained by us after the date of the license agreement with WuXi Biologics other than anti-PD-1 antibodies licensed from WuXi Biologics, subject to certain exceptions as set forth in the WuXi PD-1 Agreement. This agreement terminates, on a licensed product-by-licensed product and country-by-country basis, on expiration of the royalty term for such licensed product for the applicable country.

Abmuno License

In 2016, we entered into a license agreement (the "Abmuno Agreement") with Abmuno Therapeutics LLC ("Abmuno") for a worldwide exclusive license to develop, use, manufacture, and commercialize products that include an anti-TIGIT antibody, including domvanalimab. Under the agreement, we may be required to make additional clinical, regulatory and commercialization milestone payments of up to $88 million.

This agreement terminates on the latest of (i) the expiry of the last-to-expire Abmuno licensed patent that covers a product that contains an anti-TIGIT antibody, (ii) the date on which there is no longer an Abmuno licensed patent application that is still pending and has been pending for a certain period of time that covers a product that contains an anti-TIGIT antibody and (iii) 10 years from the date of first commercial sale.

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Manufacturing and Supply

We do not own or operate, and currently have no plans to establish, any manufacturing or storage facilities. We rely, and expect to continue to rely, on third parties for the manufacture of our investigational products for preclinical and clinical testing. If any of our investigational products obtain marketing approval, we expect to continue to use third-party manufacturers and may also use Gilead’s internal manufacturing infrastructure for their optioned products, as appropriate, to deliver commercial supply. We also rely, and expect to continue to rely, on third parties to package, label, store and distribute our investigational products, as well as for our commercial products if marketing approval is obtained. We believe that this strategy allows us to maintain a more efficient infrastructure by eliminating the need for us to invest in our own manufacturing facilities, equipment and personnel while also enabling us to focus our expertise and resources on the development of our investigational products.

To date, we have obtained active pharmaceutical ingredients ("API") and drug product for our investigational products from single-source third-party contract manufacturers. We are in the process of developing our supply chain for each of our investigational products and intend to put in place framework agreements under which third-party contract manufacturers will generally provide us with necessary quantities of API and drug product on a project-by-project basis based on our development needs. With respect to zimberelimab, we agreed, as part of the WuXi PD-1 Agreement, that WuXi Biologics would be our exclusive manufacturer of zimberelimab drug substance with respect to clinical and commercial supplies until a certain number of years after marketing approval for zimberelimab, subject to certain exceptions.

As we advance our investigational products through development, we will consider our lack of redundant supply for the API and drug product for each of our investigational products to protect against any potential supply disruptions. We generally expect to rely on third parties for the manufacture of any companion diagnostics we may develop.

Competition

The pharmaceutical and biotechnology industries are characterized by rapidly advancing technologies, intense competition and a strong emphasis on proprietary products. While we believe that our technology, development experience and scientific knowledge provide us with competitive advantages, we face potential competition from many different sources, including large pharmaceutical and biotechnology companies, academic institutions, government agencies and other public and private research organizations that conduct research, seek patent protection and establish collaborative arrangements for the research, development, manufacturing and commercialization of cancer immunotherapies. Any investigational products that we successfully develop and commercialize will compete with new immunotherapies that may become available in the future.

We compete in the segments of the pharmaceutical, biotechnology and other related markets that develop treatments for cancer and inflammatory and autoimmune diseases. There are many other companies that have commercialized and/or are developing oncology treatments for cancer including large pharmaceutical and biotechnology companies such as AstraZeneca, BeiGene, Ltd. ("BeiGene"), The Bristol-Myer Squibb Company ("Bristol-Myers Squibb"), GlaxoSmithKline plc ("GSK"), Merck, Novartis Inc. ("Novartis"), Pfizer Inc. ("Pfizer"), Regeneron Pharmaceuticals, Inc. ("Regeneron") in partnership with Sanofi Pasteur, Inc. ("Sanofi"), and Roche Holdings AG through its subsidiary Genentech ("Roche/Genentech"). There are also many other companies that have commercialized and/or are developing treatments for inflammatory and autoimmune diseases, including large pharmaceutical and biotechnology companies such as Novartis, Roche/Genentech, Celldex Therapeutics, Inc., Abbvie Inc. ("Abbvie"), Amgen Inc., Sanofi and Regeneron.

For our HIF-2α inhibitor, casdatifan, Merck received approval for belzutifan in Von Hippel-Lindau disease in 2021, advanced renal cell carcinoma in 2023 and has a number of clinical studies assessing its activity in cancer settings. Other pharmaceutical companies, including Novartis and NiKang Therapeutics, Inc., have small-molecule HIF-2α inhibitors in development. Arrowhead Pharmaceuticals Inc. has an RNA-based anti-HIF-2α agent in Phase 2 development.

For our anti-TIGIT antibody, domvanalimab, AstraZeneca has initiated more than nine registrational studies for rilvegostomig, its investigational anti-TIGIT/anti-PD-1 bispecific antibody. To our knowledge, there are no approved anti-TIGIT antibodies, and the most advanced agents are in Phase 3 development.

For our small molecule CD73 inhibitor, quemliclustat, we are aware of several pharmaceutical companies developing antibodies against this target, including AstraZeneca, Bristol-Myers Squibb, I-MAB Biopharma (Shanghai) Co., Ltd., Incyte Corporation, Innate Pharma S.A., Innovent Biologics, Inc. and Novartis, all of which have advanced their CD73 antibodies into clinical development. Other pharmaceutical companies have small-molecule programs against this target, of which we believe only Antengene Corporation Limited and ORIC Pharmaceuticals Inc. are in clinical development. To our knowledge, there are no approved CD73 molecules, and the most advanced is in Phase 3 development.

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For our anti-PD-1 antibody, zimberelimab, multiple large pharmaceutical companies have already received regulatory approvals for their anti-PD-1/PD-L1 antibodies, including AstraZeneca, BeiGene/Novartis, Bristol-Myers Squibb, Merck, Pfizer in partnership with Merck KGaA, Regeneron in partnership with Sanofi Genzyme and Roche/Genentech, and there are also many other anti-PD-1 and anti-PD-L1 antibodies in clinical development.

For our inflammation and immunology portfolio, we will be competing against large pharmaceutical and biotechnology companies with established products, such as Dupixent®, which is marketed by Sanofi and Regeneron, Xolair®, which is marketed by Genentech and Novartis, and Humira®, which is marketed by Abbvie.

Many of the companies against which we may compete have significantly greater financial resources and expertise in R&D, manufacturing, preclinical testing, conducting clinical trials, obtaining regulatory approvals and marketing approved drugs than we do. Mergers and acquisitions in the pharmaceutical, biotechnology and diagnostic industries may result in even more resources being concentrated among a smaller number of our competitors. Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These potential competitors also compete with us in recruiting and retaining qualified scientific and management personnel and in establishing clinical trial sites and enrolling subjects for our clinical trials, as well as in acquiring technologies complementary to, or necessary for, our programs.

We could see a reduction or elimination of our commercial opportunity if our competitors develop and commercialize products that are safer, more effective, have fewer or less severe side effects, are more convenient or are less expensive than any products that we or our collaborators may develop. Our competitors also may obtain FDA or foreign regulatory approval for their products more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we or our collaborators are able to enter the market. The key competitive factors affecting the success of all of our investigational products, if approved, are likely to be their efficacy, safety, convenience, price, the effectiveness of companion diagnostics (if required), the level of biosimilar or generic competition and the availability of reimbursement from government and other third-party payors.

Intellectual Property

Our commercial success depends in large part on our ability to obtain and maintain patent protection in the U.S. and other countries for our investigational products, to operate without infringing valid and enforceable patents and proprietary rights of others, and to prevent others from infringing on our proprietary or intellectual property rights. We seek to protect our proprietary position by filing, in the U.S. and other foreign jurisdictions, patent applications intended to cover the composition of matter of our investigational products, their methods of use, and related discoveries, technologies, inventions and improvements that may be commercially important to our business. We may also rely on trade secrets to protect aspects of our business that are not amenable to, or that we do not consider appropriate for, patent protection. We also intend to take advantage of regulatory protection afforded through data exclusivity, market exclusivity and patent term extensions where available.

As of February 1, 2026, our patent estate includes over 850 pending or issued patents worldwide, including 41 issued U.S. patents directed to compositions of matter, pharmaceutical compositions and methods of use for our investigational products and research programs. The term of any patents that issue will vary in accordance with the laws of each jurisdiction, but is typically 20 years from the earliest effective filing date. Our issued patents and any patents that may issue in the future from our company-owned or licensed pending applications are projected to expire between 2036 and 2045, absent any patent term adjustments or extensions.

The patent positions for biotechnology and pharmaceutical companies like us are generally uncertain and can involve complex legal, scientific and factual issues. Changes in either the patent laws or their interpretation in the U.S. and other countries may diminish our ability to protect our investigational products and enforce the patent rights that we own or license, and could affect the value of such intellectual property. With respect to both company-owned and licensed intellectual property, we cannot guarantee that the patent applications we are currently pursuing or may file in the future will issue as patents in any particular jurisdiction or whether the claims of any issued patents will provide sufficient proprietary protection from competitors. Our competitors may independently develop similar investigational products or technologies that are outside the scope of the rights granted under any issued patents that we own or exclusively in-license. We cannot be sure that any patents granted to us will be commercially useful in protecting our products or their methods of use or manufacture. Moreover, even issued patents do not guarantee us the right to commercialize our products. For example, third parties may have blocking patents that could be used to prevent us from commercializing or manufacturing our investigational products.

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Because of the extensive time required for development, testing and regulatory review of an investigational product, it is possible that, before a product can be commercialized, any patent protection for such product may expire or remain in force for only a short period following commercialization, thereby reducing the commercial advantage the patent provides. In the U.S., the term of a patent covering an FDA approved product may, in certain cases, be eligible for a patent term extension under the Hatch-Waxman Act as compensation for the loss of patent term during the FDA regulatory review process. The period of extension may be up to five years, but cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval. Only one patent among those eligible for an extension and only those claims covering the approved product, a method for using it or a method for manufacturing it may be extended. Similar provisions are available in Europe and in certain other jurisdictions to extend the term of a patent that covers an approved product. While we intend to seek patent term extensions in any jurisdictions where they are available, there is no guarantee that the applicable authorities, including the FDA, will agree with our assessment of whether such extensions should be granted, and even if granted, the length of such extensions.

Government Regulation

Government Regulation and Product Approval

Government authorities in the U.S., at the federal, state and local level, and in other countries and jurisdictions, including the European Union (the "EU"), extensively regulate, among other things, the research, development, testing, manufacture, quality control, approval, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, post-approval monitoring and reporting, and import and export of therapeutic products, such as those we are developing. The processes for obtaining regulatory approvals in the U.S. and in foreign countries and jurisdictions, along with subsequent compliance with applicable statutes and regulations and other regulatory authorities, require the expenditure of substantial time and financial resources.

FDA Approval Process

In the U.S., the FDA regulates under the Federal Food, Drug, and Cosmetic Act (the "FDCA"), and biologics under the FDCA and the Public Health Service Act (the "PHSA"), and their respective implementing regulations. These laws and other federal and state statutes and regulations, govern, among other things, the research, development, testing, manufacture, storage, recordkeeping, approval, labeling, promotion and marketing, distribution, post-approval monitoring and reporting, sampling, and import and export of drug and biological products. The process of obtaining regulatory approvals and the subsequent compliance with applicable federal, state, local and foreign statutes and regulations require the expenditure of substantial time and financial resources. Failure to comply with applicable U.S. requirements may subject a company to a variety of administrative or judicial sanctions, such as clinical hold, FDA refusal to approve pending regulatory applications, warning or untitled letters, product recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines, civil penalties, and criminal prosecution.

The process required by the FDA before a drug or biological product may be marketed in the U.S. generally includes the following:

•Completion of certain preclinical laboratory tests, animal studies and formulation studies according to Good Laboratory Practices ("GLP") or other applicable regulations;

•Submission to the FDA of an Investigational New Drug application ("IND"), which must become effective before human clinical trials may begin in the U.S.;

•Performance of adequate and well-controlled human clinical trials according to Good Clinical Practices ("GCP"), to establish the safety and efficacy of the investigational product for its intended use;

•Submissions to the FDA of a New Drug Application ("NDA") or Biologic License Application ("BLA") for a new product.

•Satisfactory completion of an FDA inspection of the facility or facilities where the investigational product is manufactured to assess compliance with the FDA’s current Good Manufacturing Practices ("cGMP"), to assure that the facilities, methods and controls are adequate to preserve the investigational product’s identity, strength, quality, purity, and potency;

•Potential FDA audit of the preclinical and clinical trial sites that generated the data in support of the NDA/BLA; and

•FDA review and approval of the NDA/BLA.

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Satisfaction of FDA pre-market approval requirements typically takes many years and the actual time required may vary substantially based upon the type, complexity, and novelty of the investigational product or disease. A clinical hold may occur at any time during the life of an IND and may affect one or more specific trials or all trials conducted under the IND.

Preclinical tests include laboratory evaluation of an investigational product’s chemistry, formulation, and toxicity, as well as animal trials to assess the characteristics and potential safety and efficacy of the investigational product. The conduct of the preclinical tests must comply with federal regulations and requirements, including GLP requirements for certain studies. The results of preclinical testing are submitted to the FDA as part of an IND along with other information, including information about an investigational product’s chemistry, manufacturing and controls, and a proposed clinical trial protocol. Long term preclinical tests, such as animal tests of reproductive toxicity and carcinogenicity, may continue after the IND is submitted. A 30-day waiting period after the submission of each IND is required prior to the commencement of clinical testing in humans. The IND automatically becomes effective 30 days after receipt by the FDA, unless the FDA, within the 30-day time period, places the clinical trial on a clinical hold. In such a case, the IND sponsor and the FDA must resolve any outstanding concerns before the clinical trial can begin. Clinical holds also may be imposed by the FDA at any time before or during clinical trials due to safety concerns about on-going or proposed clinical trials or non-compliance with specific FDA requirements, and the trials may not begin or continue until the FDA notifies the sponsor that the hold has been lifted.

Clinical trials involve the administration of the investigational product to healthy volunteers or patients under the supervision of a qualified investigator. Clinical trials must be conducted, among other things: (i) in compliance with federal regulations; (ii) in compliance with GCPs, which is comprised of standards and regulations meant to protect the rights and health of subjects and to define the roles of clinical trial sponsors, administrators, and monitors; as well as (iii) under protocols detailing the objectives of the trial, the parameters to be used in monitoring safety, and the effectiveness criteria to be evaluated. Each protocol involving testing on U.S. subjects and subsequent protocol amendments must be submitted to the FDA as part of the IND. While the IND is active, progress reports summarizing the results of the clinical trials and nonclinical studies performed since the last progress report, among other information, must be submitted at least annually to the FDA, and written IND safety reports must be submitted to the FDA and investigators for serious and unexpected suspected AEs, findings from other studies suggesting a significant risk to humans exposed to the same or similar drugs, findings from animal or in vitro testing suggesting a significant risk to humans, and any clinically important increased incidence of a serious suspected adverse reaction compared to that listed in the protocol or investigator brochure.

The FDA may order the temporary or permanent discontinuation of a clinical trial at any time, or impose other sanctions if it believes that the clinical trial either is not being conducted in accordance with FDA requirements or presents an unacceptable risk to the clinical trial subjects. The trial protocol and informed consent information for subjects in clinical trials must also be submitted to an institutional review board ("IRB") for approval. An IRB may also require the clinical trial at the site to be halted, either temporarily or permanently, for failure to comply with the IRB’s requirements, or may impose other conditions. The study sponsor may also suspend a clinical trial at any time on various grounds, including a determination that the subjects are being exposed to an unacceptable health risk. In addition, some studies also include oversight by an independent group of qualified experts organized by the clinical trial sponsor, known as a data safety monitoring board or committee. Depending on its charter, this group may determine whether a trial may move forward at designated check points based on access to certain data from the trial. There are also requirements governing the reporting of ongoing clinical studies and clinical trial results to public registries, including clinicaltrials.gov.

Clinical trials to support NDAs/BLAs for marketing approval are typically conducted in three sequential phases, but the phases may overlap. In Phase 1, the initial introduction of the investigational product into human subjects, including healthy volunteers, or in some cases patients with the target disease or condition, the investigational product is tested to assess safety, tolerability, pharmacokinetics, and pharmacological actions associated with increasing doses, and, if possible, early evidence on effectiveness. Phase 2 usually involves trials in a limited patient population to determine the effectiveness of the investigational product for a particular indication, dosage tolerance, and optimal dosage, and to identify common adverse effects and safety risks. Phase 3 trials are undertaken to obtain additional information about clinical efficacy and safety in a larger number of subjects, typically at geographically dispersed clinical trial sites, to permit the FDA to evaluate the overall benefit risk relationship of the investigational product and to provide adequate information for the labeling of the investigational product. In most cases, the FDA requires two adequate and well-controlled clinical trials to demonstrate the efficacy of the investigational product. A single Phase 3 trial may be sufficient in certain circumstances.

In some cases, the FDA may require, or sponsors may voluntarily pursue, additional clinical trials after a product is approved to gain more information about the product. These clinical trials, sometimes referred to as "Phase 4 studies," may be used to gain additional experience from the treatment of patients in the approved therapeutic indication. In certain instances, the FDA may mandate the performance of Phase 4 clinical trials as a condition of approval of an NDA.

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Concurrent with clinical trials, sponsors usually complete additional animal safety studies and also develop additional information about the chemistry and physical characteristics of the investigational product and finalize a process for manufacturing commercial quantities of the investigational product in accordance with cGMP requirements. The manufacturing process must be capable of consistently producing quality batches of the investigational product and, among other things, the manufacturer must develop methods for testing the quality, purity and potency of the investigational product. Additionally, appropriate packaging must be selected and tested and stability studies must be conducted to demonstrate that the investigational product does not undergo unacceptable deterioration over its proposed shelf-life.

After completion of the required clinical testing, an NDA, for an investigational drug product, or a BLA, for an investigational biological product, is prepared and submitted to the FDA. FDA approval of the NDA or BLA is required before marketing of the product may begin in the U.S. The NDA or BLA must include the results of all preclinical, clinical, and other testing and a compilation of data relating to the investigational product’s pharmacology, chemistry, manufacture, and controls. The cost of preparing and submitting an NDA or BLA is substantial. The submission of most NDAs and BLAs is additionally subject to a substantial application user fee, and the applicant under an approved NDA or BLA is also subject to program user fees.

The FDA has 60 days from its receipt of an NDA or BLA to determine whether the application will be accepted for filing based on the FDA’s threshold determination that the application is sufficiently complete to permit substantive review. The FDA may refuse to file any NDA or BLA that it deems incomplete or not properly reviewable at the time of submission, and may request additional information rather than accept an application for filing. In this event, the NDA or BLA must be resubmitted with the additional information and the resubmitted application also is subject to review before the FDA accepts it for filing.

Once the submission is accepted for filing, the FDA begins an in-depth review. The FDA has agreed to certain performance goals in the review of NDAs and BLAs. Most applications considered for standard review are reviewed within ten months of the date the FDA files the NDA or BLA; most applications designated for priority review are reviewed within six months of the date the FDA files the NDA or BLA. Priority review can be applied to an NDA or BLA for an investigational product that the FDA determines has the potential to treat a serious or life-threatening condition and, if approved, would be a significant improvement in safety or effectiveness compared to available therapies. The review process for both standard and priority review may be extended by the FDA for three additional months to respond to new information deemed a "major amendment" to the application.

Among other things, the FDA reviews an NDA or BLA to determine whether the product is safe and effective for its intended use, a BLA to determine whether the product is safe, pure, and potent, and in each case, whether the investigational product is being manufactured in accordance with cGMP. The FDA may also refer applications for novel investigational products, or investigational products that present difficult questions of safety or efficacy, to an advisory committee—typically a panel that includes clinicians and other experts—for review, evaluation, and a recommendation as to whether the application should be approved. The FDA is not bound by the recommendation of an advisory committee, but it considers such recommendations carefully when making decisions.

Before approving an NDA or BLA, the FDA will typically inspect one or more clinical sites to assure compliance with GCPs. Additionally, the FDA will typically inspect the facility or the facilities at which the investigational product is manufactured. The FDA will not approve the investigational product unless it determines that the manufacturing processes and facilities are in compliance with cGMP requirements and adequate to assure consistent production of the product within required specifications. To assure GCP and cGMP compliance, an applicant must incur significant expenditures of time, money and effort in the areas of training, record keeping, production and quality control.

Notwithstanding the submission of relevant data and information, the FDA may ultimately decide that the NDA or BLA does not satisfy the criteria for approval and deny approval. Data obtained from clinical trials are not always conclusive. The FDA may disagree with our trial design or interpret data from preclinical studies and clinical trials differently than we interpret the same data. If the FDA decides not to approve the NDA or BLA in its present form, the FDA will issue a complete response letter that will generally describe all of the specific deficiencies in the application identified by the FDA. The deficiencies identified may be minor, for example, requiring labeling changes, or major, for example, requiring additional clinical trials. If a complete response letter is issued, the applicant may either resubmit the NDA or BLA, addressing the deficiencies identified in the letter, or withdraw the application. If, or when, those deficiencies have been addressed to the FDA’s satisfaction in a resubmission of the NDA or BLA, the FDA will issue an approval letter. An approval letter authorizes commercial marketing of the drug or biological product in the U.S. with specific prescribing information for specific indications.

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Even if an investigational product receives regulatory approval, such approval will be granted for specific indications and dosages and the indications for use may otherwise be limited, which could restrict the commercial value of the product. Further, the FDA may require that certain contraindications, warnings or precautions be included in the product labeling. The FDA may impose restrictions and conditions on product distribution, prescribing, or dispensing in the form of a risk evaluation and mitigation strategy ("REMS"), or otherwise limit the scope of any approval. REMS can include medication guides, communication plans for healthcare professionals, and elements to assure safe use ("ETASU"). ETASU can include, but are not limited to, special training or certification for prescribing or dispensing, dispensing only under certain circumstances, special monitoring, and the use of patient registries. The requirement for a REMS can materially affect the potential market and profitability of the product. In addition, the FDA may require post marketing clinical trials, including "Phase 4" clinical trials, designed to further assess a product’s safety and effectiveness, and testing and surveillance programs to monitor the safety of approved products that have been commercialized.

Foreign Clinical Trials to Support an IND, NDA, or BLA

The FDA will accept as support for an IND, NDA, or BLA a well-designed, well-conducted, non-IND foreign clinical trial if it was conducted in accordance with GCPs and the FDA is able to validate the data from the trial through an on-site inspection, if necessary.

Regulatory applications based solely on foreign clinical data meeting these criteria may be approved if the foreign data are applicable to the U.S. population and U.S. medical practice, the trials have been performed by clinical investigators of recognized competence, and the data may be considered valid without the need for an on-site inspection by FDA or, if FDA considers such an inspection to be necessary, FDA is able to validate the data through an on-site inspection or other appropriate means. Failure of an application to meet any of these criteria may result in the application not being approvable based on the foreign data alone.

Expedited Development and Review Programs

The FDA has various programs, including Fast Track, Breakthrough Therapy, priority review, accelerated approval, and Commissioner's National Priority Voucher ("CNPV"), which are intended to expedite or simplify the process for reviewing investigational products designed to address serious or life threatening conditions, or provide for the approval of a such investigational products on the basis of an effect on a surrogate or intermediate endpoint. Even if an investigational product qualifies for one or more of these programs, the FDA may later decide that the investigational product no longer meets the conditions for qualification or that the time period for FDA review or approval will not be shortened. For example, Fast Track is a process designed to facilitate the development and expedite the review of investigational products designed to treat serious or life-threatening diseases or conditions, demonstrate the potential to address unmet medical needs for the disease or condition. The sponsor of a Fast Track investigational product has opportunities for more frequent interactions with the applicable FDA review team during product development and, once an NDA or BLA is submitted, the application may be eligible for priority review. With regard to a Fast Track investigational product, the FDA may consider for review sections of the NDA or BLA on a rolling basis before the complete application is submitted, if the sponsor provides a schedule for the submission of the sections of the NDA or BLA, the FDA agrees to accept sections of the NDA or BLA and determines that the schedule is acceptable, and the sponsor pays any required user fees upon submission of the first section of the NDA or BLA.

In addition, the FDA also provides Breakthrough Therapy designation. A sponsor may seek FDA designation of an investigational product as a "breakthrough therapy" if the investigational product is intended, alone or in combination with one or more other drugs or biologics, to treat a serious or life-threatening disease or condition, and preliminary clinical evidence indicates that the investigational product may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development. Breakthrough Therapy designation provides all the features of Fast Track designation in addition to intensive guidance on an efficient product development program beginning as early as Phase 1, and FDA organizational commitment to expedited development, including involvement of senior managers and experienced review staff in a cross-disciplinary review, where appropriate.

An NDA or BLA is also eligible for priority review if the investigational product is designed to treat a serious condition, and if approved, would provide a significant improvement in safety or efficacy compared to available therapies. The FDA will attempt to direct additional resources to the evaluation of an NDA or BLA designated for priority review in an effort to facilitate the review. The FDA endeavors to review applications with priority review designations within six months of the filing date as compared to ten months for review of new molecular entity NDAs and original BLAs under its current PDUFA review goals.

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Accelerated approval provides for an earlier approval for an investigational product that meets the following criteria: is intended to treat a serious or life-threatening disease or condition, generally provides a meaningful advantage over available therapies and demonstrates an effect on a surrogate endpoint that is reasonably likely to predict clinical benefit or on a clinical endpoint that can be measured earlier than irreversible morbidity or mortality ("IMM") that is reasonably likely to predict an effect on IMM or other clinical benefit. A surrogate endpoint is a laboratory measurement or physical sign used as an indirect or substitute measurement representing a clinically meaningful outcome. As a condition of approval, the FDA generally requires that a sponsor of a product receiving accelerated approval perform confirmatory post-marketing clinical trials to verify and describe the predicted effect on IMM or other clinical endpoint, and the product may be subject to accelerated withdrawal procedures if, for example, the confirmatory trial fails to verify the predicted clinical benefit of the product or the sponsor fails to conduct such confirmatory trials in a timely manner. In addition, for products being considered for Accelerated Approval, the FDA requires pre-approval of promotional materials within certain timeframes, which could adversely impact the timing of the commercial launch of the product.

The newly implemented CNPV approach could further shorten the review time to 1-2 months with CMC and labeling information submitted 60 days prior to the full NDA or BLA submission. However, the non-traditional review process may face legal challenges.

Orphan Drug Designation

Under the Orphan Drug Act, the FDA may grant orphan drug designation to a drug or biological product intended to treat a rare disease or condition—generally a disease or condition that affects fewer than 200,000 individuals in the U.S., or if it affects more than 200,000 individuals in the U.S., there is no reasonable expectation that the cost of developing and making a product available in the U.S. for such disease or condition will be recovered from sales of the product.

Orphan drug designation must be requested before submitting a marketing application for the therapeutic for that particular disease or condition. After the FDA grants orphan drug designation, the generic identity of the therapeutic agent and its potential orphan use are disclosed publicly by the FDA. Orphan drug designation entitles a party to financial incentives such as opportunities for grant funding toward clinical trial costs, tax advantages and user-fee waivers. Orphan drug designation does not convey any advantage in, or shorten the duration of, the regulatory review and approval process. The FDA may revoke orphan drug designation, and if it does, it will publicize the drug is no longer designated as an orphan drug.

If an investigational product with orphan drug designation subsequently receives the first FDA approval for the disease or condition for which it has such designation, the investigational product is generally entitled to orphan product exclusivity, which means that the FDA may not approve any other applications to market the same investigational product for the same approved indication or use within the designated disease or condition, except in very limited circumstances, for seven years. Orphan drug exclusivity does not prevent the FDA from approving a different drug for the same indication or use within the relevant disease or condition, or the same drug for a different disease or condition. Orphan drug exclusivity, however, could also block the approval of an investigational product for the approved orphan indication or use for seven years if a competitor obtains approval of the same investigational product, as defined by the FDA, or if such investigational product is determined to be contained within the competitor’s investigational product for the same condition or disease.

A designated orphan drug may not receive orphan drug exclusivity if it is approved for a use that is broader than the disease or condition for which it received orphan designation. In addition, orphan drug exclusive marketing rights in the U.S. may be lost if the FDA later determines that the request for designation was materially defective or, as noted above, if a second applicant demonstrates that its product is clinically superior to the approved product with orphan exclusivity within the relevant indication or the manufacturer of the approved product is unable to assure sufficient quantities of the product to meet the needs relating to the approved indication or use of patients with the rare disease or condition.

Patent Term Restoration

After approval, owners of relevant drug or biological product patents may apply for up to a five-year patent extension under the Drug Price Competition and Patent Term Restoration Act of 1984, referred to as the Hatch-Waxman Act. The allowable patent term extension is calculated as half of the product’s testing phase—the time between IND and NDA or BLA submission—and all of the review phase—the time between NDA or BLA submission and approval, up to a maximum of five years. The time can be shortened if the FDA determines that the applicant did not pursue approval with due diligence. The total patent term after the extension may not exceed 14 years.

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For patents that might expire during the application phase, the patent owner may request an interim patent extension. An interim patent extension increases the patent term by one year and may be renewed up to four times. For each interim patent extension granted, the post-approval patent extension is reduced by one year. The director of the U.S. Patent and Trademark Office (the "USPTO") must determine that approval of the investigational product covered by the patent for which a patent extension is being sought is likely. Interim patent extensions are not available for an investigational product for which an NDA or BLA has not been submitted.

Hatch-Waxman Exclusivity

Non-patent exclusivity provisions under the FDCA also can delay the submission or the approval of certain applications. The FDCA provides a five-year period of non-patent data exclusivity within the U.S. to the first applicant to gain approval of an NDA for a new chemical entity. An investigational product is a new chemical entity if the FDA has not previously approved any other new investigational product containing the same active moiety, which is the molecule or ion responsible for the action of the investigational product substance. During the exclusivity period, the FDA may not accept for review an Abbreviated New Drug Application ("ANDA") or a 505(b)(2) NDA submitted by another company for another version of such investigational product where the applicant does not own or have a legal right of reference to all the data required for approval. However, an application may be submitted after four years if it contains a certification of patent invalidity or non-infringement.

The FDCA also provides three years of non-patent data exclusivity for an NDA, 505(b)(2) NDA or supplement to an approved NDA if new clinical investigations, other than bioavailability studies, that were conducted or sponsored by the applicant are deemed by the FDA to be essential to the approval of the application, for example, for new indications, dosages or strengths of an existing investigational product. This three-year exclusivity covers only the conditions associated with the new clinical investigations and does not prohibit the FDA from approving ANDAs for investigational products containing the original active agent. Unlike five-year new chemical entity exclusivity, an award of three-year exclusivity does not block the FDA from accepting ANDA or 505(b)(2) applications; it only prevents FDA from approving such applications. Five-year and three-year exclusivity also will not delay the submission or approval of a full NDA. However, an applicant submitting a full NDA would be required to conduct or obtain a right of reference to all of the preclinical studies and adequate and well-controlled clinical trials necessary to demonstrate safety and effectiveness.

Biosimilars

The Biologics Price Competition and Innovation Act of 2009 (the "BPCIA") created an abbreviated approval pathway for biological investigational products shown to be highly similar to or interchangeable with an FDA licensed reference biological product. Biosimilarity sufficient to reference a prior FDA-approved product requires that there be no differences in conditions of use, route of administration, dosage form, and strength, and no clinically meaningful differences between the biological investigational product and the reference product in terms of safety, purity, and potency. Biosimilarity must be shown through analytical trials, animal trials, and a clinical trial or trials, unless the Secretary of the U.S. Department of Health and Human Services ("HHS") waives a required element. A biosimilar investigational product may be deemed interchangeable with a prior approved product if it meets the higher hurdle of demonstrating that it can be expected to produce the same clinical results as the reference product and, for products administered multiple times, the biologic and the reference biologic may be switched after one has been previously administered without increasing safety risks or risks of diminished efficacy relative to exclusive use of the reference biologic.

A reference biologic is granted 12 years of exclusivity from the time of first licensure of the reference product, and no application for a biosimilar can be submitted for four years from the date of licensure of the reference product. During this 12-year period of exclusivity, another sponsor may still obtain approval of a competing version of the reference product if the FDA approves a full BLA for the competing product containing that applicant’s own data. The first biologic investigational product submitted under the abbreviated approval pathway that is determined to be interchangeable with the reference product has exclusivity against a finding of interchangeability for other biologics for the same condition of use for the lesser of (i) one year after first commercial marketing of the first interchangeable biosimilar, (ii) 18 months after the first interchangeable biosimilar is approved if there is no patent challenge, (iii) 18 months after resolution of a lawsuit over the patents of the reference biologic in favor of the first interchangeable biosimilar applicant, or (iv) 42 months after the first interchangeable biosimilar’s application has been approved if a patent lawsuit is ongoing within the 42-month period. Substitution at the pharmacy level of biosimilar products deemed to be interchangeable is governed by state pharmacy law.

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Post-approval Requirements

Once an approval is granted, the FDA may withdraw the approval if compliance with regulatory requirements is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product may result in restrictions on the product or even complete withdrawal of the product from the market. After approval, some types of changes to the approved product, such as adding new indications, manufacturing changes and additional labeling claims, are subject to further FDA review and approval. In addition, the FDA may under some circumstances require testing and surveillance programs to monitor the effect of approved products that have been commercialized, and the FDA under some circumstances has the power to prevent or limit further marketing of a product based on the results of these post-marketing programs. There also are continuing, annual program fees for any marketed products. Any product manufactured or distributed pursuant to FDA approvals are subject to continuing regulation by the FDA, including, among other things:

•record-keeping requirements;

•reporting of adverse experiences associated with the product;

•providing the FDA with updated safety and efficacy information;

•therapeutic sampling and distribution requirements;

•notifying the FDA and gaining its approval of certain manufacturing or labeling changes;

•registration and listing requirements; and

•complying with FDA promotion and advertising requirements, which include, among other things, standards for direct-to-consumer advertising, restrictions on promoting products for uses or in patient populations that are not described in the product’s approved labeling, limitations on industry-sponsored scientific and educational activities and requirements for promotional activities involving the internet.

The FDA and other agencies actively enforce the laws and regulations prohibiting the promotion of off-label uses, and a company that is found to have improperly promoted off-label may be subject to significant liability. However, physicians may, in their independent medical judgment, prescribe legally available products for off-label uses. The FDA does not regulate the behavior of physicians in their choice of treatments but the FDA does restrict manufacturer’s communications on the subject of off-label use of their products.

Manufacturers, their subcontractors, and other entities involved in the manufacture and distribution of approved drug and biological products are required to register their establishments with the FDA and certain state agencies and are subject to periodic unannounced inspections by the FDA and some state agencies for compliance with cGMP, including data integrity requirements, and other laws. The FDA periodically inspects manufacturing facilities to assess compliance with ongoing regulatory requirements, including cGMP, which impose extensive procedural, substantive and record-keeping requirements upon us and third-party manufacturers engaged by us if our products are approved. In addition, changes to the manufacturing process are strictly regulated, and, depending on the significance of the change, may require FDA approval before being implemented. FDA regulations would also require investigation and correction of any deviations from cGMP and impose reporting and documentation requirements upon us and our third-party manufacturers. Accordingly, manufacturers must continue to expend time, money and effort in the area of production and quality control to maintain compliance with cGMP and other aspects of regulatory compliance. Failure to comply with the statutory and regulatory requirements can subject a manufacturer to possible legal or regulatory actions, such as:

•restrictions on the marketing or manufacturing of the product, complete withdrawal of the product from the market or product recalls;

•fines, warning letters, or untitled letters;

•clinical holds on ongoing or planned clinical studies;

•refusal of the FDA to approve pending applications or supplements to approved applications, or suspension or revocation of approvals;

•product seizure or detention, or refusal to permit the import or export of products;

•consent decrees, corporate integrity agreements, debarment or exclusion from federal healthcare programs;

•mandated modification of promotional materials and labeling and the issuance of corrective information;

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•the issuance of safety alerts, Dear Healthcare Provider letters, press releases and other communications containing warnings or other safety information about the product; or

•injunctions or the imposition of civil or criminal penalties.

In addition, therapeutic manufacturers in the U.S. must comply with applicable provisions of the Drug Supply Chain Security Act and provide and receive product tracing information, maintain appropriate licenses, ensure they only work with other properly licensed entities, and have procedures in place to identify and properly handle suspect and illegitimate product.

Disclosure of Clinical Trial Information

Sponsors of clinical drug trials (other than certain Phase 1 trials) are required to register and disclose certain clinical trial information. Information related to the investigational product, comparator(s), patient population, phase of investigation, trial sites and investigators and other aspects of the clinical trial is made public as part of the registration. Sponsors are also obligated to disclose the results of their clinical trials after completion. Disclosure of the results of certain trials may be delayed until the new product or new indication being studied has been approved. Competitors may use this publicly available information to gain knowledge regarding the progress of development programs.

Additional Controls for Biological Products

To help reduce the increased risk of the introduction of adventitious agents, the PHSA emphasizes the importance of manufacturing controls for products whose attributes cannot be precisely defined. The PHSA also provides authority to the FDA to immediately suspend licenses in situations where there exists a danger to public health, to prepare or procure products in the event of shortages and critical public health needs, and to authorize the creation and enforcement of regulations to prevent the introduction or spread of communicable diseases in the U.S. and between states.

After a BLA is approved, the biological product may also be subject to official lot release as a condition of approval. As part of the manufacturing process, the manufacturer is required to perform certain tests on each lot of the product before it is released for distribution. If the product is subject to official release by the FDA, the manufacturer submits samples of each lot of product to the FDA together with a release protocol showing a summary of the history of manufacture of the lot and the results of all of the manufacturer’s tests performed on the lot. The FDA may also perform certain confirmatory tests on lots of some products, such as viral vaccines, before releasing the lots for distribution by the manufacturer.

FDA Regulation of Companion Diagnostics

If use of an in vitro diagnostic is essential to safe and effective use of a drug or biologic product, then the FDA generally will require approval or clearance of the diagnostic, known as a companion diagnostic and regulated by FDA as a medical device, at the same time that the FDA approves the investigational product. The review of an in vitro companion diagnostic in conjunction with the review of an investigational product involves coordination of review between internal organizations within FDA. In the U.S., the FDCA and its implementing regulations, and other federal and state statutes and regulations govern, among other things, medical device design and development, preclinical and clinical testing, premarket clearance or approval, registration and listing, manufacturing, labeling, storage, advertising and promotion, sales and distribution, export and import, and post-market surveillance. Unless an exemption applies, each medical device commercially distributed in the U.S. generally requires either FDA clearance of a 510(k) premarket notification, or approval of a premarket approval ("PMA") application prior to commercial distribution. Most companion diagnostics require approval of a PMA.

If used to make critical treatment decisions, such as patient selection, the diagnostic device may be considered a significant risk device under the FDA’s Investigational Device Exemption ("IDE") regulations, in which case, the sponsor of the diagnostic device will be required to submit and obtain approval of an IDE application and subsequently comply with the IDE regulations for the use of the diagnostic device in clinical studies. However, according to FDA guidance, if a diagnostic device and a drug are to be studied together to support their respective approvals, both products can be studied in the same investigational study, if the study meets both the requirements of applicable IDE regulations and the IND regulations.

The FDA has generally required companion diagnostics designed to select the patients who may respond to cancer treatment to obtain approval of a PMA for that diagnostic simultaneously with approval of the oncology therapeutic. The PMA process, including the gathering of clinical and preclinical data and the submission to and review by the FDA, can take several years or longer. It involves a rigorous premarket review during which the applicant must prepare and provide the FDA with reasonable assurance of the device’s safety and effectiveness and information about the device and its components regarding, among other things, device design, manufacturing and labeling.

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PMAs are subject to a substantial application fee. In addition, PMAs for certain devices must generally include the results from extensive preclinical and adequate and well-controlled clinical trials to establish the safety and effectiveness of the device for each indication for which FDA approval is sought. In particular, for a diagnostic, the applicant must generally demonstrate that the diagnostic produces reproducible results when the same sample is tested multiple times by multiple users at multiple laboratories. As part of the PMA review, the FDA will typically inspect the manufacturer’s facilities for compliance with the Quality System Regulation (the "QSR") which currently imposes elaborate testing, control, documentation and other quality assurance requirements.

PMA approval is not guaranteed, and the FDA may ultimately respond to a PMA submission by denying approval, or by responding with a not approvable letter citing deficiencies in the application. To respond to such deficiencies, FDA may require the PMA sponsor to collect additional clinical trial or other data that may be expensive and time-consuming to generate and that can substantially delay approval. If the FDA’s evaluation of the PMA application is favorable, the FDA may issue an approval order, or issue an approvable letter requiring the applicant’s agreement to specific conditions, such as changes in labeling, or specific additional information, such as submission of final labeling, in order to secure final approval of the PMA. If the FDA concludes that the applicable criteria have been met, the FDA will issue an approval order for the approved indications, which can be more limited than those originally sought by the applicant. The PMA can include post-approval conditions that the FDA believes necessary to ensure the safety and effectiveness of the device, including, among other things, restrictions on labeling, promotion, sale and distribution.

After a device is placed on the market following appropriate approval or clearance from the FDA, it remains subject to significant regulatory requirements. Medical devices may be marketed only for the uses and indications for which they are cleared or approved. Device manufacturers must also establish registration and device listings with the FDA. A medical device manufacturer’s manufacturing processes and those of its suppliers are required to comply with the applicable portions of the QSR, which currently cover the methods and documentation of the design, testing, production, processes, controls, quality assurance, labeling, packaging and shipping of medical devices. Domestic facility records and manufacturing processes are subject to periodic unscheduled inspections by the FDA. The FDA also may inspect foreign facilities that export products to the U.S.

Other U.S. Healthcare Laws and Compliance Requirements

In the U.S, our activities are subject to regulation by various federal, state and local authorities in addition to the FDA, including but not limited to, the Centers for Medicare & Medicaid Services (the "CMS") other divisions of the HHS, such as the Office of Inspector General, the U.S. Department of Justice (the "DOJ") and individual U.S. Attorney offices within the DOJ, and state and local governments. These laws include, without limitation, the anti-fraud and abuse provisions of the Social Security Act and the false claims laws, each as amended, as applicable.

The federal Anti-Kickback Statute prohibits, among other things, any person or entity, from knowingly and willfully offering, paying, soliciting or receiving any remuneration, directly or indirectly, overtly or covertly, in cash or in kind, to induce or in return for purchasing, leasing, ordering or arranging for the purchase, lease or order of any item or service reimbursable, in whole or in part, under Medicare, Medicaid or other federal healthcare programs. The term remuneration has been interpreted broadly to include anything of value. The Anti-Kickback Statute has been interpreted to apply to arrangements between therapeutic product manufacturers on one hand and prescribers, purchasers, and formulary managers on the other. There are a number of statutory exceptions and regulatory safe harbors protecting some common activities from prosecution. The exceptions and safe harbors are drawn narrowly and practices that involve remuneration that may be alleged to be intended to induce prescribing, purchasing or recommending may be subject to scrutiny if they do not qualify for an exception or safe harbor. Failure to meet all of the requirements of a particular applicable statutory exception or regulatory safe harbor does not make the conduct per se illegal under the Anti-Kickback Statute. Instead, the legality of the arrangement will be evaluated on a case-by-case basis based on a cumulative review of all of its facts and circumstances. Additionally, a person or entity does not need to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation.

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The federal false claims, including the federal False Claims Act (the "FCA"), impose significant penalties and can be enforced by private citizens through civil qui tam actions, and civil monetary penalty laws prohibit any person or entity from, among other things, knowingly presenting, or causing to be presented, a false or fraudulent claim for payment to, or approval by, the federal healthcare programs, including Medicare and Medicaid, or knowingly making, using, or causing to be made or used a false record or statement material to a false or fraudulent claim to the federal government. A claim includes "any request or demand" for money or property presented to the U.S. government. For instance, historically, pharmaceutical and other healthcare companies have been prosecuted under these laws for allegedly providing free product to customers with the expectation that the customers would bill federal programs for the product. Other companies have been prosecuted for causing false claims to be submitted because of the companies’ marketing of the product for unapproved, off-label, and thus generally non-reimbursable, uses. In addition, a claim including items or services resulting from a violation of the federal Anti-Kickback Statute constitutes a false or fraudulent claim for purposes of the FCA.

The federal Health Insurance Portability and Accountability Act of 1996, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 (collectively, "HIPAA"), created additional federal criminal statutes that prohibit, among other things, knowingly and willfully executing, or attempting to execute, a scheme to defraud or to obtain, by means of false or fraudulent pretenses, representations or promises, any money or property owned by, or under the control or custody of, any healthcare benefit program, including private third-party payors, willfully obstructing a criminal investigation of a healthcare offense, and knowingly and willfully falsifying, concealing or covering up by trick, scheme or device, a material fact or making any materially false, fictitious or fraudulent statement in connection with the delivery of or payment for healthcare benefits, items or services. Like the Anti-Kickback Statute, the ACA amended the intent standard for certain healthcare fraud statutes under HIPAA such that a person or entity no longer needs to have actual knowledge of the statute or specific intent to violate it in order to have committed a violation.

Also, many states have similar, and typically more prohibitive, fraud and abuse statutes or regulations that apply to items and services reimbursed under Medicaid and other state programs, or, in several states, apply regardless of the payor. Additionally, to the extent that our product is sold in a foreign country, we may be subject to similar foreign laws.

Certain of our products, once approved, may be administered by a physician. Under currently applicable U.S. law, certain products not usually self-administered (including injectable drugs) may be eligible for coverage under Medicare through Medicare Part B. Medicare Part B is part of original Medicare, the federal health care program that provides health care benefits to the aged and disabled, and covers outpatient services and supplies, including certain pharmaceutical products, that are medically necessary to treat a beneficiary’s health condition. As a condition of receiving Medicare Part B reimbursement for a manufacturer’s eligible drugs or biologicals, the manufacturer is required to participate in other government healthcare programs, including the Medicaid Drug Rebate Program and the 340B Drug Pricing Program. The Medicaid Drug Rebate Program requires pharmaceutical manufacturers to enter into and have in effect a national rebate agreement with the Secretary of HHS as a condition for states to receive federal matching funds for the manufacturer’s outpatient drugs furnished to Medicaid patients. Under the 340B Drug Pricing Program, the manufacturer must extend discounts to entities that participate in the program.

In addition, many pharmaceutical manufacturers must calculate and report certain price reporting metrics to the government, such as Average Sales Price ("ASP") and best price. Penalties may apply in some cases when such metrics are not submitted accurately and timely. Further, these prices for drugs may be reduced by mandatory discounts or rebates required by government healthcare programs or private payors and by any future relaxation of laws that presently restrict imports of drugs from countries where they may be sold at lower prices than in the U.S. It is difficult to predict how Medicare coverage and reimbursement policies will be applied to our products for which we obtain marketing authorization, and coverage and reimbursement under different federal healthcare programs are not always consistent. Medicare reimbursement rates may also reflect budgetary constraints placed on the Medicare program.

Additionally, the federal Physician Payments Sunshine Act (the "Sunshine Act") and its implementing regulations, require that certain manufacturers of drugs, devices, biological and medical supplies for which payment is available under Medicare, Medicaid or the Children’s Health Insurance Program (with certain exceptions) report annually to CMS information related to certain payments or other transfers of value made or distributed to physicians (defined to include doctors, dentists, optometrists, podiatrists and chiropractors), other healthcare professionals (such as physician assistants and nurse practitioners), and teaching hospitals, or to entities or individuals at the request of, or designated on behalf of, the physicians and teaching hospitals and to report annually certain ownership and investment interests held by physicians and their immediate family members. Failure to report accurately could result in penalties. In addition, many states also govern the reporting of payments or other transfers of value, many of which differ from each other in significant ways, are often not pre-empted, and may have a more prohibitive effect than the Sunshine Act, thus further complicating compliance efforts.

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In order to distribute products commercially, we will need to comply with state laws that require the registration of manufacturers and wholesale distributors of drug and biological products in a state, including, in certain states, manufacturers and distributors who ship products into the state even if such manufacturers or distributors have no place of business within the state. Some states also impose requirements on manufacturers and distributors to establish the pedigree of product in the chain of distribution, including some states that require manufacturers and others to adopt new technology capable of tracking and tracing product as it moves through the distribution chain. Several states have enacted legislation requiring pharmaceutical and biotechnology companies to establish marketing compliance programs, file periodic reports with the state, make periodic public disclosures on sales, marketing, pricing, clinical trials and other activities, and/or register their sales representatives, as well as to prohibit pharmacies and other healthcare entities from providing certain physician prescribing data to pharmaceutical and biotechnology companies for use in sales and marketing, and to prohibit certain other sales and marketing practices. All of our activities are potentially subject to federal and state consumer protection and unfair competition laws.

Ensuring business arrangements with third parties comply with applicable healthcare laws and regulations is a costly endeavor. Violation of any of the federal and state healthcare laws described above or any other current or future governmental regulations that apply to drug manufacturers may result in significant penalties, including without limitation, civil, criminal and/or administrative penalties, damages, fines, disgorgement, imprisonment, exclusion from participation in government programs, such as Medicare and Medicaid, injunctions, private "qui tam" actions brought by individual whistleblowers in the name of the government, or refusal to allow us to enter into government contracts, contractual damages, reputational harm, administrative burdens, diminished profits and future earnings, additional reporting obligations and oversight if the manufacturer becomes subject to a corporate integrity agreement or other agreement to resolve allegations of non-compliance with these laws, and the curtailment or restructuring of operations.

Coverage, Pricing and Reimbursement

Significant uncertainty exists as to the coverage and reimbursement status of any investigational products for which we may obtain regulatory approval. In the U.S. and in foreign markets, sales of any products for which we receive regulatory approval for commercial sale will depend, in part, on the extent to which third-party payors provide coverage and establish adequate reimbursement levels for such products. In the U.S., third-party payors include federal and state healthcare programs, private managed care providers, health insurers and other organizations. Adequate coverage and reimbursement from governmental healthcare programs, such as Medicare and Medicaid in the U.S., and commercial payors are critical to new product acceptance.

Our ability to commercialize any products successfully also will depend in part on the extent to which coverage and reimbursement for these products and related treatments will be available from government health administration authorities, private health insurers and other organizations. Government authorities and third-party payors, such as private health insurers and health maintenance organizations, decide which therapeutics they will pay for and establish reimbursement levels. Coverage and reimbursement by a third-party payor may depend upon a number of factors, including the third-party payor’s determination that use of a therapeutic is:

•a covered benefit under its health plan;

•safe, effective and medically necessary;

•appropriate for the specific patient;

•cost-effective; and

•neither experimental nor investigational.

We cannot be sure that reimbursement will be available for any product that we commercialize and, if coverage and reimbursement are available, what the level of reimbursement will be. Coverage may also be more limited than the purposes for which the product is approved by the FDA or comparable foreign regulatory authorities. Reimbursement may impact the demand for, or the price of, any product for which we obtain regulatory approval. Additionally, our collaborators will be required to obtain coverage and reimbursement for any companion diagnostic tests they develop separate and apart from the coverage and reimbursement we seek for our investigational products, once approved.

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Third-party payors are increasingly challenging the price, examining the medical necessity, and reviewing the cost-effectiveness of medical products, therapies and services, in addition to questioning their safety and efficacy. Obtaining reimbursement for our products may be particularly difficult because of the higher prices often associated with branded drugs and drugs administered under the supervision of a physician. We may need to conduct expensive pharmacoeconomic studies in order to demonstrate the medical necessity and cost-effectiveness of our products, in addition to the costs required to obtain FDA approvals. Our investigational products may not be considered medically necessary or cost-effective. Obtaining coverage and reimbursement approval of a product from a government or other third-party payor is a time-consuming and costly process that could require us to provide to each payor supporting scientific, clinical and cost-effectiveness data for the use of our product on a payor-by-payor basis, with no assurance that coverage and adequate reimbursement will be obtained. A payor’s decision to provide coverage for a product does not imply that an adequate reimbursement rate will be approved. Further, one payor’s determination to provide coverage for a product does not assure that other payors will also provide coverage for the product. Adequate third-party reimbursement may not be available to enable us to maintain price levels sufficient to realize an appropriate return on our investment in product development. If reimbursement is not available or is available only at limited levels, we may not be able to successfully commercialize any investigational product that we successfully develop.

Different pricing and reimbursement schemes exist in other countries. In the EU, governments influence the price of pharmaceutical products through their pricing and reimbursement rules and control of national health care systems that fund a large part of the cost of those products to consumers. Some jurisdictions operate positive and negative list systems under which products may only be marketed once a reimbursement price has been agreed. To obtain reimbursement or pricing approval, some of these countries may require the completion of clinical trials that compare the cost effectiveness of a particular investigational product to currently available therapies. Other member states allow companies to fix their own prices for medicines, but monitor and control company profits. The downward pressure on health care costs has become intense. As a result, increasingly high barriers are being erected to the entry of new products. In addition, in some countries, cross-border imports from low-priced markets exert a commercial pressure on pricing within a country.

The marketability of any investigational products for which we receive regulatory approval for commercial sale may suffer if the government and third-party payors fail to provide adequate coverage and reimbursement. In addition, emphasis on managed care, the increasing influence of health maintenance organizations, and additional legislative changes in the U.S. has increased, and we expect will continue to increase, the pressure on healthcare pricing. The downward pressure on the rise in healthcare costs in general, particularly prescription medicines, medical devices and surgical procedures and other treatments, has become very intense. Coverage policies and third-party reimbursement rates may change at any time. Even if favorable coverage and reimbursement status is attained for one or more products for which we receive regulatory approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

Healthcare Reform

In the U.S. and some foreign jurisdictions, there have been, and continue to be, several legislative and regulatory changes and proposed changes regarding the healthcare system that could prevent or delay marketing approval of investigational products, restrict or regulate post-approval activities, and affect the ability to profitably sell investigational products for which marketing approval is obtained. Among policy makers and payors in the U.S. and elsewhere, there is significant interest in promoting changes in healthcare systems with the stated goals of containing healthcare costs, improving quality and/or expanding access. In the U.S., the pharmaceutical industry has been a particular focus of these efforts and has been significantly affected by major legislative initiatives. For example, the ACA has substantially changed healthcare financing and delivery by both governmental and private insurers. Among the ACA provisions of importance to the pharmaceutical and biotechnology industries, in addition to those otherwise described above, are the following: (i) increased the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program and extends the rebate program to individuals enrolled in Medicaid managed care organizations; (ii) established an annual, nondeductible fee on any entity that manufactures or imports certain specified branded prescription drugs and biologic agents apportioned among these entities according to their market share in some government healthcare programs; (iii) expanded the availability of lower pricing under the 340B drug pricing program by adding new entities to the program; (iv) increased the statutory minimum rebates a manufacturer must pay under the Medicaid Drug Rebate Program, to 23.1% and 13% of the Average Manufacturer Price ("AMP") for most branded and generic drugs, respectively and capped the total rebate amount for innovator drugs at 100% of the AMP; (v) expanded the eligibility criteria for Medicaid programs by, among other things, allowing states to offer Medicaid coverage to additional individuals, thereby potentially increasing manufacturers’ Medicaid rebate liability; (vi) created a new Patient-Centered Outcomes Research Institute to oversee, identify priorities in, and conduct comparative clinical effectiveness research, along with funding for such research; and (vii) established a Center for Medicare and Medicaid Innovation at CMS to test innovative payment and service delivery models to lower Medicare and Medicaid spending, potentially including prescription drug spending.

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There have been legal and political challenges to certain aspects of the ACA. On June 17, 2021, the U.S. Supreme Court dismissed the most recent judicial challenge to the ACA brought by several states without specifically ruling on the constitutionality of the ACA. Thus, the ACA will remain in effect in its current form. Further, there have been a number of health reform measures by the former Biden administration that have impacted the ACA. For example, on August 16, 2022, President Biden signed the Inflation Reduction Act of 2022 ("IRA"), into law, which among other things, extends enhanced subsidies for individuals purchasing health insurance coverage in ACA marketplaces through plan year 2025. The IRA also eliminates the "donut hole" under the Medicare Part D program which began in 2025 by significantly lowering the beneficiary maximum out-of-pocket cost and by creating a new manufacturer discount program.

Further legislation or regulation could be passed that could harm our business, financial condition and results of operations. Other legislative changes have been proposed and adopted since the ACA was enacted. For example, in August 2011, the Budget Control Act of 2011, was signed into law which, among other things, included aggregate reductions to Medicare payments to providers that went into effect beginning on April 1, 2013 and, due to subsequent legislation, will stay in effect until 2032 unless additional Congressional action is taken. Additionally, on March 11, 2021, the American Rescue Plan Act of 2021 was signed into law, which eliminated the statutory Medicaid drug rebate cap, which was previously set at 100% of a drug’s AMP, for single source and innovator multiple source drugs, beginning January 1, 2024.

Additionally, there has been increasing legislative and enforcement interest in the U.S. with respect to specialty drug pricing practices. Specifically, there have been several recent U.S. Congressional inquiries and proposed federal legislation designed to, among other things, bring more transparency to drug pricing, reduce the cost of prescription drugs under Medicare, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for drugs. In August 2022, the IRA was signed into law. Among other things, the IRA requires manufacturers of certain drugs to engage in price negotiations with Medicare (beginning in 2026), with prices that can be negotiated subject to a cap; imposes rebates under Medicare Part B and Medicare Part D to penalize price increases that outpace inflation (first due in 2023); and replaces the Part D coverage gap discount program with a new discounting program (which began in 2025). CMS has published the negotiated prices for the initial ten drugs, which will first be effective in 2026, and the subsequent 15 drugs, which will first be effective in 2027. The IRA permits the Secretary of HHS to implement many of these provisions through guidance, as opposed to regulation, for the initial years. HHS has and will continue to issue and update guidance as these programs are implemented, although the Medicare drug price negotiation program is currently subject to legal challenges. For that and other reasons, it is currently unclear how the IRA will be effectuated, or the impact of the IRA on our business.

The One Big Beautiful Bill Act (the "OBBBA") also included significant reforms to Medicaid, including an estimated $1 trillion in reduced federal Medicaid spending from 2025 through 2034, the imposition of work requirements for certain adult enrollees, more frequent eligibility redeterminations, and increased cost-sharing for beneficiaries. These changes are expected to reduce overall Medicaid enrollment and access to care. Although the effect on our business is currently unknown, any decrease in the number of insured patients or reimbursement levels for our products could adversely affect our revenue and commercial prospects.

In addition, the Trump administration is pursuing a two-fold strategy to reduce drug costs in the U.S. While it is unclear whether and how the Trump proposals will be implemented, the Trump policies are likely to have a negative impact on the pharmaceutical industry and on our ability to receive adequate revenues for investigational products, if approved. On the one hand, President Trump has threatened to impose significant tariffs on pharmaceutical manufacturers that do not adopt pricing policies such as most favored nation pricing, which would tie the price for drugs in the U.S. to the lowest price in a group of other countries. In response, multiple manufacturers have reportedly entered into confidential pricing agreements with the federal government. On the other hand, the Trump administration is pursuing traditional regulatory pathways to impose drug pricing policies, although final regulations have not yet been published. Even regulatory proposals or executive actions that are ultimately deemed unlawful could negatively impact the U.S. pharmaceutical sector and our business. In addition, pharmaceutical pricing and marketing has long been the subject of considerable discussion in Congress and among policymakers.

On December 7, 2023, the former Biden administration announced an initiative to control the price of prescription drugs through the use of march-in rights under the Bayh-Dole Act. On December 8, 2023, the National Institute of Standards and Technology published for comment a Draft Interagency Guidance Framework for Considering the Exercise of March-In Rights which for the first time includes the price of a product as one factor an agency can use when deciding to exercise march-in rights. While march-in rights have not previously been exercised, it is uncertain if that will continue under the new framework.

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Individual states in the U.S. have also become increasingly active in passing legislation and implementing regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and other transparency measures. Some states have enacted legislation creating so-called prescription drug affordability boards, which ultimately may attempt to impose price limits on certain drugs in these states.

We anticipate that current and future healthcare reform measures could result in additional downward pressure on coverage and the price that we receive for any approved product, and could seriously harm our business. Any reduction in reimbursement from Medicare and other government programs may result in a similar reduction in payments from private payors. The implementation of cost containment measures or other healthcare reforms may prevent us from being able to generate revenue, attain profitability from product sales, or commercialize our products. Such reforms could have an adverse effect on anticipated revenue from investigational products that we may successfully develop and for which we may obtain regulatory approval and may affect our overall financial condition and ability to develop investigational products.

The Foreign Corrupt Practices Act

The Foreign Corrupt Practices Act (the "FCPA"), prohibits any U.S. individual or business from paying, offering, or authorizing payment or offering of anything of value, directly or indirectly, to any foreign official, political party or candidate for the purpose of influencing any act or decision of the foreign entity in order to assist the individual or business in obtaining or retaining business. The FCPA also obligates companies whose securities are listed in the U.S. to comply with accounting provisions requiring us to maintain books and records that accurately and fairly reflect all transactions of the corporation, including international subsidiaries, and to devise and maintain an adequate system of internal accounting controls for international operations.

Additional Regulation

In addition to the foregoing, state and federal laws regarding environmental protection and hazardous substances, including the Occupational Safety and Health Act, the Resource Conservancy and Recovery Act and the Toxic Substances Control Act, affect our business. These and other laws govern our use, handling and disposal of various biological, chemical and radioactive substances used in, and wastes generated by, our operations. If our operations result in contamination of the environment or expose individuals to hazardous substances, we could be liable for damages and governmental fines. We believe that we are in material compliance with applicable environmental laws and that continued compliance therewith will not have a material adverse effect on our business. We cannot predict, however, how changes in these laws may affect our future operations.

Other Regulations

We are also subject to numerous federal, state and local laws relating to such matters as safe working conditions, manufacturing practices, environmental protection, fire hazard control, and disposal of hazardous or potentially hazardous substances. We may incur significant costs to comply with such laws and regulations now or in the future.

Rest of World Government Regulation

In addition to regulations in the U.S., we will be subject to a variety of regulations in other jurisdictions governing, among other things, clinical trials and any commercial sales and distribution of our products. Whether or not we obtain FDA approval to conduct clinical trials or market a product, we must obtain the requisite approvals from regulatory authorities in foreign jurisdictions prior to the commencement of clinical trials or marketing of the product in those countries. The requirements and process governing the conduct of clinical trials, product licensing, pricing and reimbursement vary from country to country. In all cases, again, the clinical trials must be conducted in accordance with GCP and the applicable regulatory requirements. Because biologically sourced raw materials are subject to unique contamination risks, their use may be restricted in some countries.

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Europe and United Kingdom

Similar to the U.S. and Australia, the conduct of clinical trials in the EU are subject to regulatory controls. The current EU Clinical Trials Regulation 536/2014 (the "Regulation") aims to simplify and streamline the approval of clinical trials in the EU. For example, the sponsor shall submit a single application for approval of a clinical trial via the EU portal. As part of the application process, the sponsor shall propose a reporting member state, who will coordinate the validation and evaluation of the application. The reporting member state shall consult and coordinate with the other concerned member states. If an application is rejected, it can be amended and resubmitted through the EU portal. If an approval is issued, the sponsor can start the clinical trial in all concerned member states. However, a concerned member state can in limited circumstances declare an "opt-out" from an approval. In such a case, the clinical trial cannot be conducted in that member state. The Regulation also aims to streamline and simplify the rules on safety reporting, and introduces enhanced transparency requirements such as mandatory submission of a summary of the clinical trial results to the EU database.

Commercialization of our investigational products may only occur in the EU following approval of a marketing application, which can be obtained through either a centralized or a decentralized procedure:

•Under the centralized procedure, a marketing application is submitted to the European Medicines Agency (the "EMA"), where it will be evaluated by the Committee for Medicinal Products for Human Use. If this committee delivers a favorable opinion, this typically results in the grant by the European Commission of a single marketing authorization that is valid for all EU member states. The centralized procedure is mandatory for certain types of drugs, such as biotechnology medicinal drugs, orphan medicinal drugs, and medicinal drugs containing a new active substance indicated for the treatment of AIDS, cancer, neurodegenerative disorders, diabetes, autoimmune and viral diseases. The centralized procedure is optional for drugs containing a new active substance not yet authorized in the European Economic Area (the "EEA"), or for drugs that constitute a significant therapeutic, scientific or technical innovation or which are in the interest of public health in the EU.

•Under the decentralized procedure, an identical dossier is submitted to the competent authorities of each of the member states in which a marketing authorization is sought, one of which is selected by the applicant as the Reference Member State (the "RMS"). The competent authority of the RMS prepares a draft assessment report, a draft summary of the drug characteristics ("SPC") and a draft of the labeling and package leaflet, which are sent to the other member states (the "Member States Concerned") for their approval. If the Member States Concerned raise no objections, based on a potential serious risk to public health, to the assessment, SPC, labeling, or packaging proposed by the RMS, the drug is subsequently granted a national marketing authorization in all the member states (i.e., in the RMS and the Member States Concerned).

We will be subject to additional regulations with respect to any activities we conduct in the EU and the UK. For example, the EU General Data Protection Regulation (the "EU GDPR") and the United Kingdom's (the "UK") General Data Protection Regulation (the "UK GDPR" and, together with the EU GDPR, the "GDPR") applies to health-related and other personal data of individuals in the EU and UK, respectively. The GPDR imposes more stringent operational requirements on processors and controllers of personal data, including, for example, expanded disclosures about how personal data is collected, used and shared, limitations on retention of personal data, more stringent requirements pertaining to genetic, biometric and health data, mandatory data breach notification requirements, and higher standards for controllers to demonstrate valid consent for certain data processing activities, as well as regulating cross-border transfers of personal data out of the EEA and the UK. The GDPR further provides that EU member states may implement their own additional laws and regulations in relation to the processing of genetic, biometric or health data, which could result in differences in the GDPR’s implementation among member states. The GDPR increases our responsibility and liability in relation to personal data that we process, and we must put in place additional mechanisms to ensure compliance with GDPR.

Data Privacy and Security

Numerous state, federal and foreign laws, regulations and standards govern the collection, use, access to, confidentiality and security of health-related and other personal information, and could apply now or in the future to our operations or the operations of our partners. In the U.S., numerous federal and state laws and regulations, including data breach notification laws, health information privacy and security laws and consumer protection laws and regulations govern the collection, use, disclosure, and protection of health-related and other personal information. In addition, certain foreign laws govern the privacy and security of personal data, including health-related data. Privacy and security laws, regulations, and other obligations are constantly evolving, may conflict with each other to complicate compliance efforts, and can result in investigations, proceedings, or actions that lead to significant civil and/or criminal penalties and restrictions on data processing.

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Human Capital Resources

Our culture and values can be defined by one overarching concept: We do the right things for the right reasons. We take pride in hard work and approach our mission—to create, develop and commercialize highly differentiated therapies that have a meaningful impact on patients—with a great sense of urgency. We recognize that our employees are a critical component to our success and we strive to attract the best talent from a range of sources, including an internship program through which we have developed strong relationships with multiple universities to foster talent and attract skilled graduates.

As of December 31, 2025, our company turnover rate is lower than the industry average. While the competition for talent remains strong as the number of biotechnology and pharmaceutical companies headquartered in the San Francisco Bay Area remains high, we believe we can attract and retain the talent we need to be successful. As of December 31, 2025, we had 601 full-time employees, approximately 49% of whom hold Ph.D., M.D., R.N., or similar degrees and certifications. Of our employees, approximately 81% were engaged in R&D activities. None of our employees are represented by labor unions or covered by collective bargaining agreements. We consider our relationship with our employees to be good.

We are an equal opportunity employer. As of December 31, 2025, among our employees, 55% were female and, among our leadership (which we define as employees at the vice president level and above), approximately 38% were female. As of December 31, 2025, 58% of our employees and 48% of our leadership identify as being from diverse racial and ethnic groups.

We recognize that attracting skilled talent is only one part of the equation. We endeavor to retain and motivate our employees by empowering them to make the decisions they are most qualified and best positioned to decide and by providing opportunities for growth and development, such as through our education reimbursement program. We focus on wellness through our company-funded lunch program, a stipend to assist with wellness and commuter expenses, and our coverage of 95% of the costs for healthcare benefits. Further, we conduct periodic talent reviews to identify high-performing and high-potential talent within the organization. This data is used to inform specific development opportunities for current and future leaders, create custom leadership training, drive meaningful development conversations and enable succession planning for key roles. We conduct an employee survey to measure employee engagement and to inform future talent initiatives.

Corporate Information

We were incorporated under the laws of the State of Delaware in April 2015. Our principal executive offices are located at 3928 Point Eden Way, Hayward, CA 94545, and our telephone number is (510) 694-6200. Our website address is www.arcusbio.com. The information on, or that can be accessed through, our website is not incorporated by reference into this Annual Report.

We operate and manage our business as one reportable and operating segment. See Note 1, Organization, liquidity and capital resources, in Part II, Item 8 for additional information.

We file Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and other information with the Securities and Exchange Commission ("SEC"). Our filings with the SEC are available free of charge on the SEC’s website at www.sec.gov and on our website under the "Investors" tab as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC.