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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2020

Commission file number 000-29889

RIGEL PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

(650) 624-1100

(Registrant’s telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Common Stock, par value $.001 per share RIGL The Nasdaq Stock Market LLC

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐No☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐No☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

Indicate by a check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes ☐ No ☒

The approximate aggregate market value of the Common Stock held by non-affiliates of the registrant, based upon the closing price of the registrant’s common stock as reported on the Nasdaq Global Select on June 30, 2020, the last business day of the registrant’s most recently completed second fiscal quarter, was $308,565,236. Shares of the registrant’s outstanding common stock held by each executive officer, director and affiliates of the registrant’s outstanding common stock have been excluded. The determination of affiliate status for the purposes of this calculation is not necessarily a conclusive determination for other purposes.

As of February 23, 2021, there were 170,041,848 shares of the registrant’s common stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

Items 10, 11, 12, 13 and 14 of Part III of this Annual Report on Form 10-K incorporate information by reference from the definitive proxy statement for the registrant’s 2021 Annual Meeting of Stockholders to be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Annual Report on Form 10-K.

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Page

PART I

Item 1. Business 4

Item 1A. Risk Factors 32

Item 1B. Unresolved Staff Comments 71

Item 2. Properties 71

Item 3. Legal Proceedings 71

Item 4. Mine Safety Disclosures 71

PART II

Item 6. Selected Financial Data 74

Item 7A. Quantitative and Qualitative Disclosures about Market Risk 92

Item 8. Financial Statements and Supplementary Data 93

Item 9A. Controls and Procedures 126

Item 9B. Other Information 128

PART III

Item 10. Directors, Executive Officers and Corporate Governance 129

Item 11. Executive Compensation 129

Item 14. Principal Accounting Fees and Services 130

PART IV

Item 15. Exhibits and Financial Statement Schedules 131

Signatures 136

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FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains statements indicating expectations about future performance and other forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the Securities Act), Section 21E of the Securities Exchange Act of 1934, as amended (the Exchange Act), and the Private Securities Litigation Reform Act of 1995, that involve risks and uncertainties. We usually use words such as “may,” “will,” “should,” “could,” “expect,” “plan,” “anticipate,” “might,” “believe,” “estimate,” “predict,” “intend” or the negative of these terms or similar expressions to identify these forward- looking statements. These statements appear throughout this Annual Report on Form 10-K and are statements regarding our current intent, belief or expectation, primarily with respect to our operations and related industry developments. Examples of these statements include, but are not limited to, statements regarding the following: our business and scientific strategies; the progress of our product development programs, including clinical testing, and the timing of commencement and results thereof; our corporate collaborations, and revenues that may be received from collaborations and the timing of those potential payments; our drug discovery technologies; our research and development expenses; protection of our intellectual property; and sufficiency of our cash resources and need for additional capital. You should not place undue reliance on these forward-looking statements. Our actual results could differ materially from those anticipated in these forward-looking statements for many reasons, including as a result of the risks and uncertainties discussed under the heading “Risk Factors” in Part I, Item 1A of this Annual Report on Form 10-K. A forward- looking statement speaks only as of the date on which it is made, and, except as required by law, we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for us to predict which factors will arise. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements.

RISK FACTOR SUMMARY

Investing in our securities involves a high degree of risk. Below is a summary of the material factors that make an investment in our common stock speculative or risky. This summary does not address all of the risks that we face. Additional discussion of the risks summarized in this risk factor summary, as well as other risks that we face, can be found below under the heading “Risk Factors” and should be carefully considered, together with other information in this Form 10-K and our other filings with the SEC, before making an investment decision regarding our common stock.

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PART I

Item 1. Business

Overview

We are a biotechnology company dedicated to discovering, developing and providing novel small molecule drugs that significantly improve the lives of patients with hematologic disorders, cancer and rare immune diseases. Our pioneering research focuses on signaling pathways that are critical to disease mechanisms. Our first United States Food and Drug Administration (FDA) approved product is TAVALISSE® (fostamatinib disodium hexahydrate) tablets, the only oral spleen tyrosine kinase (SYK) inhibitor, for the treatment of adult patients with chronic immune thrombocytopenia who have had an insufficient response to a previous treatment. The product is also commercially available in Europe (TAVLESSE) and Canada (TAVALISSE) for the treatment of chronic immune thrombocytopenia in adult patients.

Fostamatinib is currently being studied in a Phase 3 trial for the treatment of warm autoimmune hemolytic anemia (wAIHA); a National Institutes of Health (NIH)/National Heart, Lung, and Blood Institute (NHLBI)-sponsored Phase 2 trial for the treatment of hospitalized COVID-19 patients, in collaboration with Inova Health System; and a Phase 2 trial for the treatment of COVID-19 being conducted by Imperial College London. Additionally, we have launched a Phase 3 clinical trial of fostamatinib for the treatment of hospitalized COVID-19 patients.

Our other clinical programs include our interleukin receptor-associated kinase (IRAK) inhibitor program and a receptor-interacting serine/threonine-protein kinase (RIP1) inhibitor program in clinical development with partner Eli Lilly and Company (Lilly). In addition, we have product candidates in clinical development with partners AstraZeneca AB (AZ), BerGenBio ASA (BerGenBio) and Daiichi Sankyo (Daiichi).

Business Update

TAVALISSE in ITP

During the year ended December 31, 2020, net product sales of TAVALISSE was $61.7 million which represented a year over year increase of 41% from 2019. This was primarily due to improved persistency of therapy among patients on TAVALISSE, the continued uptake and use of the product in steroid refractory patients, and to a lesser extent, annual price increase of our drug.

Due to the evolving effects of the COVID-19 pandemic, resources have been deployed to enable our field-based employees to continue to engage virtually with health care providers. These virtual engagements have enabled our field team to support existing prescribers, as well as develop new prescribers to identify appropriate patients for TAVALISSE. We also conducted market research with chronic ITP (cITP) prescribers in 2020 to understand the impact of COVID on cITP management. More than half of respondents reported that COVID had an impact on their management of cITP, and about a third of respondents anticipate a surge of patients post-COVID. This is because clinicians have found it challenging to both start a therapy, and switch to new therapies.

A post-hoc analysis from our Phase 3 clinical program in adult patients with chronic ITP, highlighting the potential benefit of using TAVALISSE in earlier lines of therapy, was published in the British Journal of Haematology in July 2020. Inclusion in one of the leading peer-reviewed journals in the field of hematology underscores the significance of the 78% (25/32) response rate defined as at least one platelet count of at least 50,000/μL when TAVALISSE was used as a second-line therapy in our Phase 3 clinical program. Adverse events were manageable and consistent with those previously reported with fostamatinib. Our sales force is now sharing this data with physicians.

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Fostamatinib in Global Markets

In February 2020, we received a $20.0 million payment from Grifols. The payment was received upon the European Commission’s (EC) approval of the Marketing Authorization Application (MAA) for fostamatinib for the treatment of chronic ITP in adult patients who are refractory to other treatments. In addition, as a result of the EC approval, $25.0 million of the $30.0 million upfront fee that we previously received from Grifols will no longer be repayable by us to Grifols. Fostamatinib is marketed in Europe under the brand name TAVLESSE (fostamatinib). Grifols launched TAVLESSE in the UK and Germany in July 2020, and thereafter, expects a phased roll-out over the next 18 months across Europe. In December 2020, the Scottish Medicines Consortium accepted TAVLESSE for use in NHS in Scotland.

In October 2019, we entered into exclusive commercialization license agreements with Medison to commercialize fostamatinib in all potential indications in Canada and Israel. In November 2020, Health Canada approved the new drug submission for TAVALISSE for the treatment of thrombocytopenia in adult patients with chronic ITP who have had an insufficient response to other treatments. In Israel, a decision on the new drug application is anticipated during the second quarter of 2021.

We currently anticipate no significant disruption related to the COVID-19 pandemic in the supply of TAVALISSE tablets and drug substance to meet the needs for our U.S. ITP sales, as well as for our collaborative partners and clinical trials worldwide.

Fostamatinib in AIHA

Our FORWARD study, a pivotal Phase 3 clinical trial in warm AIHA has enrolled 66 of the 90 patients targeted for enrollment. Currently, the FORWARD study has over 90 clinical trial sites established across 22 countries and a limited number of clinical trial sites have resumed screening patients after a temporary pause due to the ongoing COVID-19 pandemic. In December 2020, the FDA has granted Fast Track designation to TAVALISSE for the treatment of warm AIHA based on the significant medical need that exists and the product's potential in the treatment of these patients. Fast Track designation is designed to enable an expedited review process for any potential regulatory filings. We continue to experience slower than expected enrollment in light of COVID-19 impacts, and at this time, we are unable to provide an update on anticipated enrollment completion.

Fostamatinib in Hospitalized COVID-19 patients

In November 2020, we launched our Phase 3 clinical trial to evaluate the safety and efficacy of fostamatinib in hospitalized COVID-19 patients without respiratory failure that have certain high-risk prognostic factors. This multi-center, double-blind, placebo-controlled, adaptive study design will randomly assign either fostamatinib plus standard of care (SOC) or matched placebo plus SOC (1:1) to approximately 308 evaluable patients. Treatment will be administered orally twice daily for 14 days with follow up to day 60. The primary endpoint of this study is the proportion of subjects who progress to severe/critical disease within 29 days. In January 2021, we were awarded $16.5 million by the U.S. Department of Defense’s (DOD) Joint Program Executive Office for Chemical, Biological, Radiological and Nuclear Defense to support this Phase 3 clinical trial.

In September 2020, we announced a Phase 2 clinical trial sponsored by the NIH/NHLBI to evaluate the safety of fostamatinib for the treatment of hospitalized COVID-19 patients. This multi-center, double-blind, placebo-controlled study will randomly assign fostamatinib or matched placebo (1:1) to approximately 60 evaluable patients. Treatment will be administered orally twice daily for 14 days. There will be a follow-up period to day 60. The primary endpoint of this study is cumulative incidence of serious adverse events (SAE) through day 29. The trial also includes multiple secondary endpoints designed to assess the early efficacy and clinically relevant endpoints of disease course. The study is projected to complete the enrollment of the 60 evaluable patients in the first quarter of 2021 and we expect to report topline data in April 2021.

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In July 2020, we announced a Phase 2 clinical trial sponsored by Imperial College London in order to evaluate the efficacy of fostamatinib for the treatment of COVID-19 pneumonia. This is a two-stage, open label, controlled clinical trial with patients randomized (1:1:1) to fostamatinib plus SOC, ruxolitinib plus SOC, or standard of care alone. Treatment will be administered twice daily for 14 days and patients will receive a follow-up assessment at day 7, day 14 and day 28 after the first dose. The primary endpoint of this study is progression from mild to severe COVID-19 pneumonia within 14 days in hospitalized patients. Initially, n=171 (57 per arm) patients will be recruited in Stage 1. Following interim analysis to assess the efficacy and safety of the treatments, approximately n=285 (95 per arm) will be recruited during Stage 2. In November 2020, we announced that the Imperial College London-sponsored clinical trial began enrolling patients, and as of the date hereof, there are 106 patients enrolled under this study.

The Broad Institute of the Massachusetts Institute of Technology (MIT) and Harvard led a recent screen to identify FDA-approved compounds that reduce mucin-1 (MUC1) protein abundance. MUC1 is a biomarker used to predict the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) and correlates with poor clinical outcomes. In June 2020, the results were presented. Of the 3,713 compounds that were screened, fostamatinib was the only compound identified which both decreased expression of MUC1 and is FDA approved, and so allows for rapid repurposing for patients with COVID-19 lung injury. Fostamatinib demonstrated preferential depletion of MUC1 from epithelial cells without affecting cell viability. The research was focused on drug repurposing for the much lower risk of toxicity and the ability of FDA-approved treatments to be delivered on a shortened timescale, which is critical for patients afflicted with lung disease resulting from COVID-19.

In vitro studies led by the Amsterdam University Medical Center at the University of Amsterdam, showed that R406, the active metabolite of fostamatinib, blocked macrophage hyper-inflammatory responses to a combination of immune complexes formed by anti-Spike IgG in serum from severe COVID-19 patients. Anti-Spike IgG levels are known to correlate with the severity of COVID-19. These results, presented in July 2020, suggest that by inhibiting anti-Spike IgG-mediated hyperinflammation, R406 could potentially play a role in the prevention of cytokine storms as well as pulmonary edema and thrombosis associated with severe COVID-19.

In December 2020, the Journal of Infectious Diseases published research from NIH which demonstrated that R406, the active metabolite of fostamatinib, was able to inhibit NETosis ex vivo in donor plasma from patients with COVID-19. NETosis is a unique type of cell death resulting in the release of neutrophil extracellular traps (NETs). NETs contribute to thromboinflammation and have been associated with mortality in COVID-19. These data provide insights for how fostamatinib may mitigate neutrophil-associated mechanisms contributing to COVID-19 immunopathogenesis.

Global Strategic Partnership with Lilly

In February 2021, we entered into a global exclusive license agreement and strategic collaboration with Lilly to co-develop and commercialize R552, a receptor-interacting serine/threonine-protein kinase 1 (RIP1) inhibitor, for the treatment of non-central nervous system (non-CNS) diseases. In addition, the collaboration is aimed at developing additional RIP1 inhibitors for the treatment of CNS diseases. Pursuant to the terms of the license agreement, we granted to Lilly exclusive rights to develop and commercialize R552 and related RIP1 inhibitors in all indications worldwide. The parties’ collaboration is governed through a joint governance committee and appropriate subcommittees.

The parties are jointly responsible for performing development activities for R552 and other non-CNS disease development candidates. We are responsible for 20% of development costs for R552 in the U.S., Europe, and Japan, up to a specified cap. Lilly is responsible for funding the remainder of all development activities for R552 and other non-CNS disease development candidates. We have the right to opt-out of co-funding the R552 development activities in the U.S., Europe and Japan at two different specified times. If we exercise our first opt-out right, we will continue to fund our share of the R552 development activities in the U.S., Europe, and Japan up to a maximum funding commitment of $65.0 million.

We are responsible for performing and funding initial discovery and identification of CNS disease development candidates, which is nearly completed, and future funding is expected to be minimal. Following candidate selection,

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Lilly will be responsible for performing and funding all future development and commercialization of the CNS disease development candidates.

Under the terms of the license agreement, we will receive an upfront cash payment of $125.0 million, with the potential for an additional $330.0 million in milestone payments upon the achievement of specified development and regulatory milestones by non-CNS disease products and $255.0 million in milestone payments upon the achievement of specified development and regulatory milestones by CNS disease products. We are also eligible to receive up to $100.0 million in sales milestone payments on a product-by-product basis for non-CNS disease products and up to $150.0 million in sales milestone payments on a product-by-product basis for CNS disease products. In addition, depending on the extent of our co-funding of R552 development activities, we would be entitled to receive tiered royalty payments on net sales of non-CNS disease products at percentages ranging from the mid-single digits to high-teens, subject to certain standard reductions and offsets. We would be entitled to receive tiered royalty payments on net sales of CNS disease products up to low-double digits, subject to certain standard reductions and offsets.

This transaction is subject to customary closing conditions, including clearance under the Hart-Scott-Rodino (HSR) Antitrust Improvements Act of 1976.

Other Updates

In June 2020, at the European League Against Rheumatism 2020 E-Congress, we presented two oral and two poster presentations highlighting our investigational compound R835, a potent and selective inhibitor of both IRAK1 and IRAK4. In multiple pre-clinical models of acute and chronic inflammation, R835 administration resulted in reduced inflammation, and in Phase 1 trials, it showed encouraging pharmacokinetic (PK) properties.

In May 2020, we accessed the second $10.0 million tranche from our $60.0 million credit facility with MidCap Financial (MidCap). The facility provides us with access to an additional $40.0 million which is subject to the achievement of certain conditions. Additionally, on August 4, 2020, we entered into an Open Market Sale AgreementSM (Sales Agreement) with Jefferies LLC (Jefferies), as our sole sales agent, pursuant to which we may sell, from time to time, through Jefferies, shares of our common stock having an aggregate offering price of up to $65.0 million. As of December 31, 2020, we have not yet sold any shares under the Sales Agreement.

Management Update

In August 2020, we announced the appointment of David Santos as our new executive vice president and chief commercial officer to replace Eldon C. Mayer, III who resigned effective in December 2019. Mr. Santos brings over 30 years of commercial experience in the biopharmaceutical industry with companies such as Bristol-Myers Squibb, Lilly, Genentech, and most recently Jazz Pharmaceuticals, where he led the Hematology/Oncology Business Unit. He has a robust track record of success in sales and marketing leadership roles, building commercial capabilities, and growing brands in the hematology-oncology area, where he has spent most of his career.

In October 2020, Nelson D. Cabatuan, resigned from his position as Vice President, Finance and Principal Accounting Officer, and employment with the Company.

Update on Current and Potential Future Impact of COVID-19 on our Business

We are continuing to monitor the impact of the evolving effects of the COVID-19 pandemic and have undertaken, and plan to continue to undertake, safety measures to keep our staff, patients, investigators and stockholders safe and to help the communities where we live and work reduce the number of people exposed to the virus. We have previously implemented work-from-home policies for certain employees and restricted on-site staff at our office in South San Francisco to only those personnel performing essential activities. In March 2020, through our existing Crisis Management Team (CMT), we also activated our business continuity plans to prevent or minimize business disruption and ensure the safety and well-being of our personnel. Our CMT meets regularly to assess the effectiveness of our business continuity plans and make adjustments accordingly as COVID-19 continues to evolve. The ultimate impact of

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the COVID-19 pandemic on our business and financial condition is highly uncertain and subject to change, and as such, we cannot ascertain the full extent of the impacts on our sales of our product, our ability to continue to secure new collaborations and support existing collaboration efforts with our partners and our clinical and regulatory activities.

Since the COVID-19 pandemic was declared, we have observed reduced patient-doctor interactions and our representatives are having fewer visits with health care providers, which negatively affected our ability to grow our product sales and may continue to negatively affect our product sales in the future. Resources have been deployed to enable our field team to have virtual engagements to support existing prescribers as well as partner with new prescribers to identify appropriate patients for TAVALISSE. Other commercial related activities, such as our marketing programs, speaker bureaus, and market access initiatives that were in live forums have been conducted virtually, delayed or cancelled as a result of the COVID-19 pandemic.

With respect to our supply chain, we currently do not anticipate significant disruption in the supply chain for our commercial product, TAVALISSE. However, we do not know the full extent of the impact on our supply chain if the COVID-19 pandemic continues and persists for an extended period of time.

For further information regarding the impacts of the evolving effects of the COVID-19 pandemic on our ability and the ability of our collaborators to effectively market, sell and distribute our products and to develop our products and product candidates, see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Overview” in Part II Item 7 of this Annual Report on Form 10-K.”

See also the section titled “Risk Factors” in Item 1A of this Annual Report on Form 10-K for additional information on risks and uncertainties related to the ongoing COVID-19 pandemic.

Strategy

Our goal is to establish ourselves as a successful commercial stage biopharmaceutical company with significant research capabilities. We aim to expand our commercial business in the U.S. on our own and globally through partnerships. We continue our research and development of novel small molecule drugs that significantly improve the lives of patients with hematological disorders, cancer and immune diseases through our innovative drug discovery platform. We continue to maintain a strong commercial team in the U.S. to enable us to execute successfully on our commercialization strategy for TAVALISSE in chronic ITP. We entered into partnerships for the expansion of fostamatinib into Europe, Asia, Turkey, Canada, and Israel, and will be concentrating on the further development of the utility of fostamatinib in other indications on our own or through our partners. We also aim to expand our development pipeline on our own and/or with partnerships with pharmaceuticals and biotechnology companies to further develop and market additional product candidates.

In particular, there are four key elements that we believe are value drivers, which we plan to continue to execute on:

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Our Product Portfolio

The following table summarizes our portfolio:

Commercial Product

TAVALISSE in ITP

Disease background. Chronic ITP affects an estimated 81,300 adult patients in the U.S. In patients with ITP, the immune system attacks and destroys the body’s own blood platelets, which play an active role in blood clotting and healing. ITP patients can suffer extraordinary bruising, bleeding and fatigue as a result of low platelet counts. Current therapies for ITP include steroids, blood platelet production boosters that imitate thrombopoietin (TPOs) and splenectomy.

Orally-available fostamatinib program. Taken in tablet form, fostamatinib blocks the activation of SYK inside immune cells. ITP is typically characterized by the body producing antibodies that attach to healthy platelets in the blood stream. Immune cells recognize these antibodies and affix to them, which activates the SYK enzyme inside the immune cell, and triggers the destruction of the antibody and the attached platelet. When SYK is inhibited by fostamatinib, it interrupts this immune cell function and allows the platelets to escape destruction. The results of our Phase 2 clinical trial, in which fostamatinib was orally administered to 16 adults with chronic ITP, published in Blood, showed that fostamatinib significantly increased the platelet counts of certain ITP patients, including those who had failed other currently available agents.

Our Fostamatinib for Immune Thrombocytopenia (FIT) Phase 3 clinical program had a total of 150 ITP patients which were randomized into two identical multi-center, double-blind, placebo-controlled clinical trials. The patients were diagnosed with persistent or chronic ITP, and had blood platelet counts consistently below 30,000 per microliter of blood. Two-thirds of the subjects received fostamatinib orally at 100 mg twice daily bid and the other third received placebo on the same schedule. Subjects were expected to remain on treatment for up to 24 weeks. At week four of treatment, subjects who failed to meet certain platelet counts and met certain tolerability thresholds could have their dosage of fostamatinib (or corresponding placebo) increased to 150 mg bid. The primary efficacy endpoint of this

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program was a stable platelet response by week 24 with platelet counts at or above 50,000 per microliter of blood for at least four of the final six qualifying blood draws. In August 2015, the FDA granted our request for Orphan Drug designation for fostamatinib for the treatment of ITP. In February 2020, Kissei was granted orphan drug designation from the Japanese Ministry of Health, Labour and Welfare for R788 (fostamatinib) in chronic idiopathic thrombocytopenic purpura.

In August 2016, we announced the results of the first FIT study, reporting that fostamatinib met the study’s primary efficacy endpoint. The study showed that 18% of patients receiving fostamatinib achieved a stable platelet response compared to none receiving a placebo control (p=0.0261). In October 2016, we announced the results of the second FIT study, reporting that the response rate was 18%, consistent with the first study. However, one patient in the placebo group (4%) achieved a stable platelet response, therefore the difference between those on treatment and those on placebo did not reach statistical significance (p=0.152) and the study did not meet its primary endpoint. Using the most conservative sensitivity analysis, rather than the protocol’s prespecified analysis, one more patient in the second study is considered a non-responder, resulting in 8 of 50 (16%) responders on fostamatinib (p = 0.256 vs. placebo). When the data from both studies are combined, however, this difference is statistically significant (p=0.007).

Patients from the FIT studies were given the option to enroll in a long-term open-label extension study and receive treatment with fostamatinib, also a Phase 3 trial. A total of 123 patients enrolled in this study. All the patients who responded to fostamatinib in the FIT studies and enrolled in the long-term open-label extension study maintained a median platelet count of 106,500/uL at a median of 16 months. In addition, there were 44 placebo non-responders that enrolled in the long-term open-label extension study, 41 of which patients had at least 12 weeks of follow-up. Of those, 9 patients (22%) have achieved a prospectively defined stable platelet response, which is statistically significant (p=0.0078) and similar to the response rate fostamatinib achieved in the parent studies.

A stable response was defined as a patient achieving platelet counts of greater than 50,000/uL on more than 4 of the 6 visits between weeks 14 and 24, without rescue medication. In the post-study analysis we performed, a clinically-relevant platelet response was defined to include patients achieving one platelet count over 50,000/uL during the first 12 weeks of treatment, in absence of rescue medication, but who did not otherwise meet the stable response criteria. Once the platelet count of greater than 50,000/uL is achieved, a loss of response was defined as two consecutive platelet counts of less than 30,000/uL in any subsequent visits. In the combined dataset of both stable and clinically-relevant platelet responders for the FIT studies, the response rate was 43% (43/101), compared to 14% (7/49) for placebo (p=0.0006).

The most frequent adverse events were gastrointestinal-related, and the safety profile of the product was consistent with prior clinical experience, with no new or unusual safety issues uncovered.

TAVALISSE was approved by the FDA in April 2018 for the treatment of ITP in adult patients who have had an insufficient response to a previous treatment, and successfully launched in the U.S. in May 2018. In January 2020, the EC granted our MAA in Europe for fostamatinib for the treatment of chronic ITP in adult patients who are refractory to other treatments.

Commercial launch activities, including sales and marketing

A significant portion of our business operations was related to our commercial launch activities for TAVALISSE. Specifically, our marketing and sales efforts are focused on targeting hematologists and hematologist-oncologists in the United States, who manage chronic adult ITP patients. Grifols launched TAVLESSE in the UK and Germany in July 2020, and thereafter, expects a phased roll-out over the next 18 months across Europe.

We have a fully integrated commercial team consisting of sales, marketing, market access, and commercial operations functions. Our sales team promotes TAVALISSE in the U.S. wherein, in the ordinary course of the business, we use customary pharmaceutical company practices to market our products in the U.S. and concentrate our efforts on hematologists and hematologists-oncologists. TAVALISSE is sold initially through third-party wholesale distribution and specialty pharmacy channels and group purchasing organizations before being ultimately prescribed to patients. To facilitate our commercial activities in the U.S., we also enter into arrangements with various third-parties, including advertising agencies, market research firms and other sales-support-related services as needed. We believe that our

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commercial team and distribution practices are adequate to ensure that our marketing efforts reach our target customers and deliver our products to patients in a timely and compliant fashion. Also, to help ensure that all eligible patients in the U.S. have appropriate access to TAVALISSE, we have established a comprehensive reimbursement and patient support program called Rigel One Care (ROC). Through ROC, we provide co-pay assistance to qualified, commercially insured patients to help minimize out-of-pocket costs and provide free drug to uninsured or under-insured patients who meet certain clinical and financial criteria. In addition, ROC is designed to provide comprehensive reimbursement support services, such as prior authorization support, benefits investigation and appeals support.

Competitive landscape for TAVALISSE

Our industry is intensely competitive and subject to rapid and significant technological change. TAVALISSE is competing with other existing therapies. In addition, a number of companies are pursuing the development of pharmaceuticals that target the same diseases and conditions that we are targeting. For example, there are existing therapies and drug candidates in development for the treatment of ITP that may be alternative therapies to TAVALISSE.

Currently, corticosteroids remain the most common first line therapy for ITP, occasionally in conjunction with intravenous immuglobulin (IVIg) or anti-Rh(D) to help further augment platelet count recovery, particularly in emergency situations. However, it has been estimated that frontline agents lead to durable remissions in only a small percentage of newly-diagnosed adults with ITP. Moreover, concerns with steroid-related side effects often restrict therapy to approximately four weeks. As such, many patients progress to persistent or chronic ITP, requiring other forms of therapeutic intervention. In long-term treatment of chronic ITP, patients are often cycled through several therapies over time in order to maintain a sufficient response to the disease.

Even with the above treatment options, a significant number of patients remain severely thrombocytopenic for long durations and are subject to risk of spontaneous or trauma-induced hemorrhage. The addition of fostamatinib to the treatment options could be beneficial since it has a different mechanism of action than any of the therapies that are currently available. Fostamatinib is a potent and relatively selective SYK inhibitor, and its inhibition of Fc receptors and B-cell receptors of signaling pathways make it a potentially broad immunomodulatory agent.

Other products in the U.S. that are approved by the FDA to increase platelet production through binding and TPO receptors on megakaryocyte precursors include PROMACTA® (Novartis International AG (Novartis)), Nplate® (Amgen, Inc.) and DOPTELET® (Swedish Orphan Biovitrum AB).

Fostamatinib in Global Markets

We have entered into various license agreements to commercialize fostamatinib globally. The following describes the arrangements we had in place as of December 31, 2020 with Grifols, Kissei and Medison. We retain the global rights to fostamatinib outside of the Grifols, Kissei and Medison territories.

Fostamatinib in Europe/Turkey

In January 2019, we entered into an exclusive commercialization license agreement with Grifols to commercialize fostamatinib for the treatment, palliation, or prevention of human diseases, including chronic or persistent ITP and AIHA in Europe and Turkey. Pursuant to the terms of the license agreement, Grifols has exclusive rights to commercialize, and non-exclusive rights to develop, fostamatinib in Europe and Turkey. Grifols also received an exclusive option to expand the territory under its exclusive and non-exclusive licenses to include the Middle East, North Africa and Russia (including Commonwealth of Independent States). In November 2020, Grifols exercised its option to include these territories under the agreement.

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We are responsible for performing and funding certain development activities for fostamatinib for ITP and AIHA and Grifols is responsible for all other development activities for fostamatinib in such territories. We remain responsible for the manufacture and supply of fostamatinib for all development and commercialization activities under the agreement. In December 2019, we entered into a Drug Product Purchase Agreement with Grifols wherein we agreed to supply and sell to Grifols the drug product requested under an executed first and only purchase order until Grifols enters into a supply agreement directly with a third-party drug product manufacturer.

Under the terms of the agreement, we received an upfront cash payment of $30.0 million and will be eligible to receive regulatory and commercial milestones of up to $297.5 million, which included a $20 million non-refundable payment received in the first quarter of 2020, comprised of a $17.5 million payment for EMA approval of fostamatinib for the first indication and a $2.5 million creditable advance royalty payment due upon EMA approval of fostamatinib in the first indication. We will also receive tiered royalty payments ranging from the mid-teens to 30% of net sales of fostamatinib in Europe and Turkey.

In January 2020, we received approval of our MAA for fostamatinib for the treatment of chronic ITP in adult patients who are refractory to other treatments. With this approval, we received a $20 million payment as described above. Grifols launched TAVLESSE in the UK and Germany in July 2020, and thereafter, expects a phased roll-out over the next 18 months across Europe. In December 2020, the Scottish Medicines Consortium accepted TAVLESSE for use in NHS in Scotland.

Fostamatinib in Japan/Asia

In October 2018, we entered into an exclusive license and supply agreement with Kissei to develop and commercialize fostamatinib in all current and potential indications in Japan, China, Taiwan and the Republic of Korea. Kissei is a Japan-based pharmaceutical company addressing patients' unmet medical needs through its research, development and commercialization efforts, as well as through collaborations with partners.

Under the terms of the agreement, we received an upfront cash payment of $33.0 million, with the potential for an additional $147.0 million in development and commercial milestone payments, and will receive product transfer price payments in the mid to upper twenty percent range based on tiered net sales for the exclusive supply of fostamatinib. Kissei receives exclusive rights to fostamatinib in ITP and all future indications in Japan, China, Taiwan, and the Republic of Korea. Rigel retains the global rights to fostamatinib outside the Kissei, Grifols and Medison territories.

In September 2019, our collaboration partner, Kissei, initiated a Phase 3 trial in Japan of fostamatinib in adult patients with chronic ITP. The efficacy and safety of orally administered fostamatinib will be assessed by comparing it with placebo in a randomized, double-blind study. Japan has the third highest prevalence of chronic ITP in the world behind the U.S. and EU. In February 2020, Kissei was granted orphan drug designation from the Japanese Ministry of Health, Labour and Welfare for R788 (fostamatinib) in chronic ITP.

Fostamatinib in Canada/Israel

In October 2019, we entered into exclusive commercialization license agreements with Medison to commercialize fostamatinib in all potential indications in Canada and Israel. Under the terms of the agreements, we will receive an upfront payment of $5.0 million with the potential for approximately $35.0 million in regulatory and commercial milestones. In addition, we will receive royalty payments beginning at 30% of net sales. Under our agreement with Medison for the Canada territory, we have the option to buy back all rights to the product upon regulatory approval in Canada for the indication of AIHA. The buyback provision if exercised would require both parties to mutually agree on commercially reasonable terms for us to purchase back the rights, taking into account Medison’s investment and the value of the rights, among others. Pursuant to this exclusive commercialization license agreement, in August 2020, we entered into a commercial supply agreement with Medison.

In November 2020, Health Canada approved the New Drug Submission for TAVALISSE for the treatment of thrombocytopenia in adult patients with chronic ITP who have had an insufficient response to other treatments. Medison is anticipating a decision on a New Drug Application in the second quarter of 2021.

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Clinical Stage Programs

Fostamatinib—AIHA

Disease background. AIHA is a rare, serious blood disorder where the immune system produces antibodies that result in the destruction of the body's own red blood cells. Symptoms can include fatigue, shortness of breath, rapid heartbeat, jaundice or enlarged spleen. While no medical treatments are currently approved for AIHA, physicians generally treat acute and chronic cases of the disorder with corticosteroids, other immuno-suppressants, or splenectomy. Research has shown that inhibiting SYK with fostamatinib may reduce the destruction of red blood cells. This disorder affects an estimated 45,000 Americans, for whom no approved treatment options currently exist.

Orally-available fostamatinib program. We completed our Phase 2 clinical trial, also known as the SOAR study in patients with warm AIHA. This trial was an open-label, multi-center, two-stage study that evaluated the efficacy and safety of fostamatinib in patients with warm AIHA who had previously received treatment for the disorder but have relapsed. The primary efficacy endpoint of this study was to achieve increased hemoglobin levels by week 12 of greater than 10 g/dL, and greater than or equal to 2 g/dL higher than baseline. In November 2019, we announced updated data that in a Phase 2 open-label study of fostamatinib in patients with warm AIHA, data showed that 44% (11/25) of evaluable patients met the primary efficacy endpoint of a Hgb level >10 g/dL with an increase of ≥2 g/dL from baseline by week 24. Including one late responder at week 30, the overall response rate was 48% (12/25). Adverse events were manageable and consistent with those previously reported with fostamatinib.

In March 2019, we initiated our warm AIHA pivotal Phase 3 clinical study of fostamatinib, known as FORWARD study. The clinical trial protocol calls for a placebo-controlled study of approximately 90 patients with primary or secondary warm AIHA who have failed at least one prior treatment. The primary endpoint will be a durable Hgb response, defined as Hgb > 10 g/dL and > 2 g/dL increase from baseline and durability measure, with the response not being attributed to rescue therapy.

In May 2019, we enrolled the first patient in the FORWARD study. Currently, we have enrolled 66 patients of the 90 patients targeted for enrollment. The FORWARD study has over 90 clinical trial sites established across 22 countries and a limited number of clinical trial sites have resumed screening patients after a temporary pause due to the ongoing COVID-19 pandemic. Given the uncertainty of the COVID-19 pandemic, we are experiencing slower than expected enrollment and are unable to provide an update on anticipated enrollment completion.

In November 2020, we reached an agreement with the FDA on the durable response measure for the primary efficacy endpoint of the study as well as the inclusion of additional secondary endpoints. In January 2021, we announced that the FDA had granted Fast Track designation to TAVALISSE for the treatment of warm AIHA. The FDA previously granted TAVALISSE Orphan Drug designation for the treatment of warm AIHA in January 2018.

Fostamatinib—in Hospitalized COVID-19 Patients

Disease background.COVID-19 is the infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). SARS-CoV-2 primarily infects the upper and lower respiratory tract and can lead to ARDS. Additionally, some patients develop other organ dysfunction including myocardial injury, acute kidney injury, shock resulting in endothelial dysfunction and subsequently micro and macrovascular thrombosis. Much of the underlying pathology of SARS-CoV-2 is thought to be secondary to a hyperinflammatory immune response associated with increased risk of thrombosis. SYK is involved in the intracellular signaling pathways of many different immune cells. Therefore, SYK inhibition may improve outcomes in patients with COVID-19 via inhibition of key Fc gamma receptor (FcγR) and c-type lectin receptor (CLR) mediated drivers of pathology such as inflammatory cytokine release by monocytes and macrophages, production of NETs by neutrophils, and platelet aggregation. Furthermore, SYK inhibition in neutrophils and platelets may lead to decreased thromboinflammation, alleviating organ dysfunction in critically ill patients with COVID-19.

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Orally-available fostamatinib program. In November 2020, we launched a Phase 3 clinical trial to evaluate the safety and efficacy of fostamatinib in hospitalized COVID-19 patients without respiratory failure that have certain high-risk prognostic factors. This multi-center, double-blind, placebo-controlled, adaptive design study will randomly assign either fostamatinib plus SOC or matched placebo plus SOC (1:1) to approximately 308 evaluable patients. Treatment will be administered orally twice daily for 14 days with follow up to day 60. The primary endpoint of this study is the proportion of subjects who progress to severe/critical disease within 29 days.

In September 2020, we announced a Phase 2 clinical trial to be sponsored by the NIH/NHLBI in order to evaluate the safety of fostamatinib for the treatment of hospitalized COVID-19 patients. This multi-center, double-blind, placebo-controlled study will randomly assign fostamatinib or matched placebo (1:1) to approximately 60 evaluable patients. Treatment will be administered orally twice daily for 14 days. There will be a follow-up period to day 60. The primary endpoint of this study is cumulative incidence of serious adverse events (SAE) through day 29. The trial also includes multiple secondary endpoints designed to assess the early efficacy and clinically relevant endpoints of disease course. The study is projected to complete the enrollment of the 60 evaluable patients in the first quarter of 2021 and we expect to report topline data in April 2021.

In July 2020, we announced a Phase 2 clinical trial sponsored by Imperial College London in order to evaluate the efficacy of fostamatinib for the treatment of COVID-19 pneumonia. This is a two-stage, open label, controlled clinical trial with patients randomized (1:1:1) to fostamatinib plus SOC, ruxolitinib plus SOC, or standard of care alone. Treatment will be administered twice daily for 14 days and patients will receive a follow-up assessment at day 14 and day 28 after the first dose. The primary endpoint of this study is progression from mild to severe COVID-19 pneumonia within 14 days in hospitalized patients. In November 2020, we announced that the Imperial College London-sponsored clinical trial began enrolling patients, and as of the date hereof, there are 106 patients enrolled under this study.

Researchers at MIT and Harvard led a recent screen to identify FDA-approved compounds that reduce MUC1 protein abundance. MUC1 is a biomarker used to predict the development of ALI and ARDS and correlates with poor clinical outcomes. In June 2020, the results were presented. Of the 3,713 compounds that were screened, fostamatinib was the only compound identified which both decreased expression of MUC1 and is FDA approved. Fostamatinib demonstrated preferential depletion of MUC1 from epithelial cells without affecting cell viability. The research was focused on drug repurposing for the much lower risk of toxicity and the ability of FDA-approved treatments to be delivered on a shortened timescale, which is critical for patients afflicted with lung disease resulting from COVID-19.

In addition, recent in vitro studies led by the Amsterdam University Medical Center at the University of Amsterdam, showed that R406, the active metabolite of fostamatinib, blocked macrophage hyperinflammatory responses to a combination of immune complexes formed by anti-Spike IgG in serum from severe COVID-19 patients. Anti-Spike IgG levels are known to correlate with the severity of COVID-19. These results, presented in July 2020, suggest that by inhibiting anti-Spike IgG-mediated hyperinflammation, R406 could potentially play a role in the prevention of cytokine storms as well as pulmonary edema and thrombosis associated with severe COVID-19.

In December 2020, the Journal of Infectious Diseases published research from NIH which demonstrated that R406, the active metabolite of fostamatinib, was able to inhibit NETosis ex vivo in donor plasma from patients with COVID-19. NETosis is a unique type of cell death resulting in the release of NETs. NETs contribute to thromboinflammation and have been associated with mortality in COVID-19. These data provide insights for how fostamatinib may mitigate neutrophil-associated mechanisms contributing to COVID-19 immunopathogenesis.

R835, an Oral IRAK1/4 Inhibitor for Autoimmune, Inflammatory and Hematology-Oncology Diseases

Orally Available IRAK 1/4 Inhibitor Program.During the second quarter of 2018, we selected R835, a proprietary molecule from our IRAK 1/4 preclinical development program, for human clinical trials. This investigational candidate was an orally administered, potent and selective inhibitor of IRAK1 and IRAK4 that blocks inflammatory cytokine production in response to toll-like receptor (TLR) and the interleukin-1 (IL-1R) family receptor signaling. TLRs and IL-1Rs play a critical role in the innate immune response and dysregulation of these pathways can lead to a variety of inflammatory conditions including psoriasis, rheumatoid arthritis, inflammatory bowel disease and gout (among others). R835 prevents cytokine release in response to TLR and IL-1R activation in vitro. R835 is active in multiple

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rodent models of inflammatory disease including psoriasis, arthritis, lupus, multiple sclerosis and gout. Preclinical studies show that R835 inhibits both the IRAK1 and IRAK4 signaling pathways, which play a key role in inflammation and immune responses to tissue damage. Dual inhibition of IRAK1 and IRAK4 allows for more complete suppression of pro-inflammatory cytokine release.

In October 2019, we announced results from a Phase 1 clinical trial of R835 in healthy subjects to assess safety, tolerability, PK and pharmacodynamics. The Phase 1 study was a randomized, placebo-controlled, double-blind trial in 91 healthy subjects, ages 18 to 55. The Phase 1 trial showed positive tolerability and PK data as well as established proof-of-mechanism by demonstrating the inhibition of inflammatory cytokine production in response to a lipopolysaccharide (LPS) challenge.

We continue to advance the development of our IRAK1/4 program, which includes R835, an orally available, potent and selective inhibitor that inhibits both IRAK1 and IRAK4. We are currently identifying therapeutic opportunities in the areas of hematology/oncology and rare immunology diseases.

R552, a RIP1 Inhibitor for Autoimmune and Inflammatory Diseases

Orally Available RIP1 Inhibitor Program. R552, is a potent and selective inhibitor of RIP1. RIP1 is believed to play a critical role in induction of necroptosis. Necroptosis is a form of regulated cell death where the rupturing of cells leads to the dispersion of their inner contents, which activates immune responses and enhances inflammation.

Initial data from our completed Phase 1 study in healthy volunteers suggests that R552 has an attractive PK and safety profile with a half-life of approximately 14 hours which may allow for once a day dosing. In preclinical studies, R552 was shown to prevent joint and skin inflammation in a RIP1-mediated murine model of inflammation and tissue damage.

In February 2021, we entered into a global exclusive license agreement with Lilly to co-develop and commercialize R552 for all indications, including autoimmune and inflammatory diseases, as well as other non-CNS disease development candidates. In addition, Lilly will lead all clinical development and commercialization of brain penetrating RIP1 inhibitors in CNS diseases.

Partnered Clinical Programs

R548 (ATI-501 and ATI-502) - Aclaris

Aclaris is developing ATI-501 and ATI-502, an oral and topical janus kinase (JAK) 1/3 inhibitor discovered in Rigel’s laboratories. ATI- 501 is being developed as an oral treatment for patients with alopecia areata (AA), including the more severe forms of AA that result in total scalp hair loss, known as alopecia totalis (AT), and total hair loss on the scalp and body, known as alopecia universalis (AU).

In December 2018, Aclaris also reported on the enrollment and/or results for a number of Phase 2 studies with ATI-502 for the topical treatment of AA and Vitiligo, including results from its AUATB-201 study.

In June 2019, Aclaris reported positive results from its Phase 2 clinical trial of ATI-502 topical (AGA-201) in patients with androgenetic alopecia (AGA), a condition commonly known as male/female-pattern baldness. There were no treatment-related serious adverse events. Later in June 2019, Aclaris reported that its Phase 2 clinical trial of ATI-502 topical (AA-201) in patients with AA did not meet its endpoints. ATI-502 was observed to be generally well-tolerated. Adverse events were primarily mild or moderate in severity. No treatment-related serious adverse events were reported.

In July 2019, Aclaris announced that ATI-501 achieved statistically significant improvement over placebo in several measures of hair growth, including the primary endpoint and certain secondary endpoints of this trial. ATI-501 was observed to be generally well-tolerated at all doses. There were no serious adverse events reported. All adverse events (AEs) were mild or moderate in severity and rates of AEs were similar across all groups. No thromboembolic events were observed in the trial.

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Aclaris is currently seeking a development and commercialization partner for ATI-501 and ATI-502 as potential treatments for alopecia.

BGB324 - BerGenBio

BerGenBio is conducting Phase 1/2 studies with BGB324 (bemcentinib), a first-in-class selective AXL kinase inhibitor, as a single agent in relapsed acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS); and in combination with erlotinib (Tarceva®) in advanced (EGFR-positive) non-small-cell lung carcinoma. BerGenBio is also conducting Phase 2 studies with BGB324 in combination with KEYTRUDA® (pembrolizumab) in non-small cell adenocarcinoma of the lung and triple negative breast cancer in collaboration with another company.

In November 2019, BerGenBio showed that the primary endpoint of Overall Response Rate (ORR) had been met in Cohort A of its Phase 2 clinical trial evaluating bemcentinib in combination with KEYTRUDA as a potential new treatment regimen for previously treated advanced non-small cell lung cancer (NSCLC). The primary efficacy endpoint requires that at least 25% evaluable patients achieve a clinical response when treated with the novel drug combination, defined as either complete or partial response, as measured by Response Evaluation Criteria in Solid Tumors (RECIST). A secondary endpoint of median Progression Free Survival (mPFS) reported significant 3-fold improvement in AXL positive vs negative patients, as defined by BerGenBio’s composite AXL tumor-immune score.

In December 2019, BerGenBio reported results in combination with low-dose cytarabine (LDAC) in elderly AML patients. The bemcentinib-LDAC combination was safe and well tolerated in elderly AML patients. The overall response rate and duration surpass historical benchmarks and compare favorably to other LDAC combinations.

In April 2020, BerGenBio announced that bemcentinib has been selected as the first potential treatment to be fast-tracked in a new UK national multi-center randomized Phase 2 clinical trial initiative to potentially receive an early indication of bemcentinib’s effectiveness in treating the most vulnerable patients with COVID-19.

In June 2020, BerGenBio confirmed dosing the first COVID-19 patient with bemcentinib at the University Hospital Southampton NHS Foundation Trust. The Phase 2 trial has commenced in seven more sites across the UK, with the plan to recruit approximately 120 subjects to assess safety and efficacy of bemcentinib as an add-on therapy to standard of care in approximately 60 hospitalized COVID-19 patients with the other approximately 60 control group patients receiving standard of care. Bemcentinib has exhibited potent anti-viral activity in preclinical models against several enveloped viruses, including Ebola and Zika virus and as of recently, to the COVID-19 virus. Bemcentinib is a small molecule inhibitor that targets a cell-surface protein called AXL, which is one of several cell surface receptors used by enveloped viruses to enter cells. Bemcentinib inhibits virus entry into cells and also prevents inhibition of Type I Interferon, the cell’s anti-viral defense mechanism, suggesting potential use in the treatment of COVID-19 infection.

In June 2020, BerGenBio announced positive interim clinical and translational data from Cohort B, stage 1 of the Phase 2 trial (BGBC008) evaluating bemcentinib in combination with Merck & Co.’s KeytrudaTM in previously treated NSCLC patients with confirmed progression on prior immune checkpoint therapy. The trial is recruiting patients in the second stage of the cohort.

In July 2020, BerGenBio announced that its first patient was dosed in a trial assessing bemcentinib in recurrent glioblastoma (GBM). The trial is sponsored by Ichiro Nakano, MD, Professor in the Department of Neurosurgery and co-leader of the Neuro-Oncology Program at University of Alabama at Birmingham, and is funded by the National Cancer Institute. This is an open label, multi-center, intra-tumoral tissue PK study of bemcentinib in patients with recurrent GBM for whom a surgical resection is medically indicated. The trial intends to enroll up to 20 recurrent GBM patients, at up to 15 sites in the U.S. The end points of the study include an evaluation of bemcentinib’s ability to cross the blood brain barrier, AXL expression, PK, safety and tolerability, as well as efficacy assessments including PFS and Overall Survival.

In October 2020, BerGenBio announced first patient enrolled in Phase 2 trial assessing bemcentinib as a potential treatment for COVID-19 patients in India and South Africa and in December 2020, BerGenBio announced that

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the first patient has been enrolled with bemcentinib in the UK Research and Innovation (UKRI) funded COVID-19 ACCORD clinical study.

DS-3032 - Daiichi

DS-3032 is an investigational oral selective inhibitor of the murine double minute 2 (MDM2) protein currently being investigated by Daiichi in three Phase 1 clinical trials for solid and hematological malignancies including AML, acute lymphocytic leukemia, chronic myeloid leukemia in blast phase, lymphoma and MDS.

Preliminary safety and efficacy data from a Phase 1 study of DS-3032 suggests that DS-3032 may be a promising treatment for hematological malignancies including relapsed/refractory AML and high-risk MDS. Evaluation of additional dosing schedules of DS-3032 is underway and combination studies with fostamatinib are currently being conducted by Daiichi.

In September 2020, worldwide rights to DS-3032 were out-licensed from Daiichi to Rain Therapeutics Inc.

For the year ended December 31, 2020, we recognized $2.1 million of revenue as a result of the achievement of a milestone in accordance with the Amended Collaboration Agreement dated April 20, 2005 with Daiichi. All deliverables under the agreement had been delivered as of September 30, 2020, as such the above payment was recognized as revenue in the third quarter of 2020. We received the milestone payment from Daiichi in October 2020.

AZ-D0449 – AZ

AZ is currently conducting a Phase 1 study in healthy volunteers and patients with mild asthma to investigate the safety, anti-inflammatory effect of inhaled AZ-D0449. The study, which follows the single and multiple ascending doses, is currently recruiting patients.

Research/Preclinical Programs

We are conducting proprietary research in the broad disease areas of inflammation/immunology, immuno-oncology and cancers. Within these disease areas, our researchers are investigating mechanisms of action as well as screening compounds against potential novel targets and optimizing those leads that appear to have the greatest potential.

Commercialization and Sponsored Research and License Agreements

We conduct research and development programs independently and in connection with our corporate collaborators. As of December 31, 2020, we are a party to collaboration agreements with ongoing performance obligations, with Kissei for the development and commercialization of fostamatinib in Japan, China, Taiwan and the Republic of Korea and with Grifols to commercialize fostamatinib in all indications, including chronic ITP and AIHA, in Europe and Turkey and with Medison to commercialize fostamatinib in all indications, including chronic ITP and AIHA in Canada and Israel. As of December 31, 2020, we are also a party to collaboration agreements, but do not have ongoing performance obligations with Aclaris for the development and commercialization of JAK inhibitors for the treatment of alopecia areata and other dermatological conditions, AZ for the development and commercialization of R256, an inhaled JAK inhibitor, BerGenBio for the development and commercialization of AXL inhibitors in oncology, and Daiichi to pursue research related to MDM2 inhibitors, a novel class of drug targets called ligases.

Under these agreements, which we entered into in the ordinary course of business, we received or may be entitled to receive upfront cash payments, payments contingent upon specified events achieved by such partners and royalties on any net sales of products sold by such partners under the agreements. Total future contingent payments to us under all of these agreements could exceed $607.2 million if all potential product candidates achieved all of the payment triggering events under all of our current agreements (based on a single product candidate under each agreement). Of this amount, up to $67.5 million relates to the achievement of development events, up to $163.7 million relates to the achievement of regulatory events and up to $376.0 million relates to the achievement of certain commercial or launch events. This estimated future contingent amount does not include any estimated royalties that could be due to us if the

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partners successfully commercialize any of the licensed products. Future events that may trigger payments to us under the agreements are based solely on our partners’ future efforts and achievements of specified development, regulatory and/or commercial events.

In July 2020, Grifols launched TAVLESSE in Germany and the UK, and thereafter expects a phased roll-out over the next 18 months across Europe. In December 2020, the Scottish Medicines Consortium accepted TAVLESSE for use in NHS in Scotland. In addition, our partner, Kissei is currently conducting a Phase 3 clinical trial for fostamatinib in ITP in Japan.

In February 2021, we entered into a global exclusive license agreement and strategic collaboration with Lilly to co-develop and commercialize R552, a receptor-interacting serine/threonine-protein kinase 1 (RIP1) inhibitor, for the treatment of non-central nervous system (non-CNS) diseases. In addition, the collaboration is aimed at developing additional RIP1 inhibitors for the treatment of CNS diseases, whereby the Company is responsible for performing and funding initial discovery and identification of CNS disease development candidates, which is nearly completed, and future funding is expected to be minimal. Following candidate selection, Lilly will be responsible for performing and funding all future development and commercialization of the CNS disease development candidates.

Grifols License Agreement

In January 2019, we entered into an exclusive license agreement with Grifols to commercialize fostamatinib in all indications, including chronic ITP and AIHA, in Europe and Turkey. Under the agreement, we received an upfront payment of $30.0 million, with the potential for $297.5 million in total regulatory and commercial milestones, which included a $20.0 million payment upon approval from the EMA for fostamatinib in chronic ITP as discussed below. We will also receive stepped double-digit royalty payments based on tiered net sales which may reach 30% of net sales. In return, Grifols will receive exclusive rights to fostamatinib in human diseases, including chronic ITP and AIHA, in Europe and Turkey. Grifols also received an exclusive option to expand the territory under its exclusive and non-exclusive licenses to include the Middle East, North Africa and Russia (including Commonwealth of Independent States). In November 2020, Grifols exercised its option to include these territories as part of the licensed territories under the agreement. The agreement also requires us to conduct the Phase 3 trial in AIHA.

In January 2020, we received European Commission’s approval of our MAA for fostamatinib for the treatment of chronic immune thrombocytopenia in adult patients who are refractory to other treatments. With this approval, we received in February 2020 a $20.0 million non-refundable payment, which is comprised of a $17.5 million payment for EMA approval of fostamatinib for the first indication and a $2.5 million creditable advance royalty payment, based on the terms of our collaboration agreement with Grifols.

Kissei License Agreement

In October 2018, we entered into an exclusive license and supply agreement with Kissei to develop and commercialize fostamatinib in all current and potential indications in Japan, China, Taiwan and the Republic of Korea. Kissei is responsible for performing and funding all development activities for fostamatinib in the above-mentioned territories. We received an upfront cash payment of $33.0 million, with the potential for up to an additional $147.0 million in development, regulatory and commercial milestone payments, and will receive mid to upper twenty percent, tiered, escalated net sales-based payments for the supply of fostamatinib. Under the agreement, we granted Kissei the license rights to fostamatinib in the territories above and are obligated to supply Kissei with drug product for use in clinical trials and pre-commercialization activities. We are also responsible for the manufacture and supply of fostamatinib for all future development and commercialization activities under the agreement.

Medison Commercial and License Agreements

In October 2019, we entered into two exclusive commercial and license agreements with Medison for the commercialization of fostamatinib for chronic ITP in Israel and in Canada pursuant to which we received a $5.0 million upfront payment under our agreement in Canada. We accounted for the agreement made with an upfront payment under ASC 606 and identified the following combined performance obligations at inception of the agreement: (a) granting of

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the license and (b) obtaining regulatory approval in Canada of fostamatinib in ITP. We determined that the non-refundable upfront fee of $5.0 million represented the transaction price. However, under the agreement, we have the option to buy back all rights to the product in Canada within six months that we obtain regulatory approval in Canada of the product for the indication of AIHA. The buyback option precludes us from transferring control of the license to Medison under ASC 606. We believe that the buyback provision, if exercised, will require us to repurchase the license at an amount equal to or more than the upfront $5.0 million. As such this arrangement is accounted for as a financing arrangement. Accrued interest related to this financing arrangement as of December 31, 2020 is immaterial. Pursuant to this exclusive commercialization license agreement, in August 2020, we entered into a commercial supply agreement with Medison.

Other license agreements

For the year ended December 31, 2020, we recognized $2.1 million of revenue as a result of the achievement of a milestone in accordance with the Amended Collaboration Agreement dated April 20, 2005 with Daiichi. All deliverables under the agreement had been previously delivered, as such the above payment has been recognized as revenue in the third quarter of 2020. We received the milestone payment from Daiichi in October 2020.

Our Discovery Engine

The approaches that we use in connection with both our proprietary product development programs and our corporate collaborations are designed to identify protein targets for compound screening and validate the role of those targets in the disease process. Unlike genomics-based approaches, which begin by identifying genes and then searching for their functions, our approach identifies proteins that are demonstrated to have an important role in a specific disease pathway. By understanding the disease pathway, we attempt to avoid studying genes that will not make good drug targets and focus only on the subset of expressed proteins of genes that we believe are specifically implicated in the disease process.

We begin by developing assays that model the key events in a disease process at the cellular level. We then identify potential protein targets. In addition, we identify the proteins involved in the intracellular process and prepare a map of their interactions, thus giving us a comprehensive picture of the intracellular disease pathway. We believe that our approach has a number of advantages, including:

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Because of the very large numbers of screens employed, our technology is labor intensive. The complexity of our technology requires a high degree of skill and diligence to perform successfully. We believe we have been and will continue to be able to meet these challenges successfully and increase our ability to identify targets for drug discovery.

Pharmacology and Preclinical Development

We believe that the rapid characterization and optimization of compounds identified in high-throughput screening (HTS) will generate high quality preclinical development candidates. Our pharmacology and preclinical development group facilitates lead optimization by characterizing lead compounds with respect to PK, potency, efficacy and selectivity. The generation of proof-of-principle data in animals and the establishment of standard pharmacological models with which to assess lead compounds represent integral components of lead optimization. As programs move through the lead optimization stage, our pharmacology and preclinical development groups support our chemists and biologists by performing the necessary studies, including toxicology, for IND application submissions.

Clinical Development

We have assembled a team of experts in drug development to design and implement clinical trials and to analyze the data derived from these trials. The clinical development group possesses expertise in project management and regulatory affairs. We work with external clinical research organizations with expertise in managing clinical trials, drug formulation, and the manufacture of clinical trial supplies to support our drug development efforts.

Intellectual Property

We are able to protect our technology from unauthorized use by third parties only to the extent that it is covered by valid and enforceable patents or is effectively maintained as a trade secret. Accordingly, patents and other proprietary rights are an essential element of our business. As of December 31, 2020, we had 67 pending patent applications and 357 issued and active patents in the United States, as well as corresponding pending foreign patent applications and issued foreign patents. Our policy is to file patent applications to protect technology, inventions and improvements to inventions that are commercially important to the development of our business. We seek U.S. and international patent protection for a variety of technologies, including new screening methodologies and other research tools, target molecules that are associated with disease states identified in our screens, and lead compounds that can affect disease pathways. We also intend to seek patent protection or rely upon trade secret rights to protect other technologies that may be used to discover and validate targets and that may be used to identify and develop novel drugs. We seek protection, in part, through confidentiality and proprietary information agreements. We are a party to various license agreements that give us rights to use technologies in our research and development.

We currently hold a number of issued patents in the United States, as well as corresponding applications that allow us to pursue patents in other countries, some of which have been allowed and/or granted and others of which we expect to be granted. Specifically, in most cases where we hold a U.S. issued patent, the subject matter is covered at least by an application filed under the Patent Cooperation Treaty (PCT), which is then used or has been used to pursue protection in certain countries that are members of the treaty. Our patents extend for varying periods according to the date of patent filing or grant and the legal term of patents in the various countries where patent protection is obtained. Some of these patents may be eligible for patent term extensions, depending on their subject matter and length of time required to conduct clinical trials. Our material patents relate to fostamatinib, an oral SYK inhibitor, that is the active pharmaceutical ingredient in TAVALISSE, and R406, the active metabolite of fostamatinib. These patents will expire in 2023, 2026, 2028, 2030, 2031, 2032 and 2034.

Fostamatinib. Fostamatinib is covered as a composition of matter in a U.S. issued patent that has an expected expiration date of September 2031, after taking into account a patent term adjustment and extension rules. Fostamatinib is also covered under broader composition of matter claims in a U.S. issued patent that has an expiration date in March 2026, after taking into account a patent term adjustment. Additional patents covering fostamatinib composition of matter, methods for use, formulations, methods for making and intermediates expire in 2023, 2026, 2028, 2030, 2032 and 2034. Corresponding applications have been filed in foreign jurisdictions under the PCT, and are at various stages

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of prosecution. Of note, a patent covering fostamatinib as a composition of matter and in compositions for use treating various diseases has been granted by the European Patent Office.

R406. R406 is covered as a composition of matter in a U.S. issued patent and, with a patent term adjustment, has an expiration date in February 2025. R406 is also covered under two broader composition of matter patents issued in the U.S. expiring in February 2023 and July 2024. Methods of using R406 to treat various indications and compositions of matter covering certain intermediates used to make R406 are also covered under patents described above. Corresponding applications have been filed in foreign jurisdictions under the PCT and are at various stages of prosecution.

Competition

The biotechnology and pharmaceutical industries are intensely competitive and subject to rapid and significant technological change. Many of the drugs that we are attempting to discover will be competing with existing therapies. In addition, a number of companies are pursuing the development of pharmaceuticals that target the same diseases and conditions that we are targeting.

There are existing therapies and drug candidates in development for the treatment of ITP that may be alternative therapies to TAVALISSE. Currently, corticosteroids remain the most common first line therapy for ITP, occasionally in conjunction with intravenous immuglobulin (IVIg) or anti-Rh(D) as added agents to help further augment platelet count recovery, particularly in emergency situations. However, it has been estimated that frontline agents lead to durable remissions in only a small percentage of newly-diagnosed adults with ITP. Moreover, concerns with steroid-related side effects often restrict therapy to approximately four weeks. As such, many patients progress to persistent or chronic ITP, requiring other forms of therapeutic intervention.

The FDA can approve an Abbreviated New Drug Application (ANDA) for a generic version of a branded drug without the ANDA applicant undertaking the clinical testing necessary to obtain approval to market a new drug. In September 2019, the FDA published product-specific bioequivalence guidance on fostamatinib disodium to let potential ANDA applicants understand the data the FDA would expect to see for approval of a generic version of TAVALISSE. The ANDA process can result in generic competition if the patents at issue are not upheld or if the generic competitor is found not to infringe our patents. In September 2019, the FDA published product-specific bioequivalence guidance on fostamatinib disodium to let potential ANDA applicants understand the data FDA would expect to see for approval of a generic version of TAVALISSE.

Other approaches to treat ITP are varied in their mechanism of action, and there is no consensus about the sequence of their use. Options include splenectomy, thrombopoietin receptor agonists (TPO-RAs) and various immunosuppressants (such as rituximab). The response rate criteria of the above-mentioned options vary, precluding a comparison of response rates for individual therapies. According to the most recent ITP guideline from the ASH, there was a lack of evidence to support strong recommendations for various management approaches. In general, strategies that avoided medication side effects were favored. A large focus was placed on shared decision-making especially with regard to second-line therapy.

Even with the above treatment options, a significant number of patients remain severely thrombocytopenic for long durations and are subject to risk of spontaneous or trauma-induced hemorrhage. The addition of fostamatinib to the treatment options could be beneficial since it has a different mechanism of action than the TPO agonists. Fostamatinib is a potent and relatively selective SYK inhibitor, and its inhibition of Fc receptors and B-cell receptors signaling pathways make it a potentially broad immunomodulatory agent.

Other products in the U.S. that are approved by the FDA to increase platelet production through binding and TPO receptors on megakaryocyte precursors include PROMACTA® (Novartis), Nplate® (Amgen, Inc.) and DOPTELET® (Dova Pharmaceuticals).

We face, and will continue to face, intense competition from pharmaceutical and biotechnology companies, as well as from academic and research institutions and government agencies, both in the United States and abroad. Some of

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these competitors are pursuing the development of pharmaceuticals that target the same diseases and conditions as our research programs. Our major competitors include fully integrated pharmaceutical companies that have extensive drug discovery efforts and are developing novel small molecule pharmaceuticals. We also face significant competition from organizations that are pursuing the same or similar technologies, including the discovery of targets that are useful in compound screening, as the technologies used by us in our drug discovery efforts.

Competition may also arise from:

● new or better methods of target identification or validation;

● generic version of TAVALISSE or of products with which we compete;

● new small molecules; or

● other classes of therapeutic agents.

Our competitors or their collaborative partners may utilize discovery technologies and techniques or partner with collaborators in order to develop products more rapidly or successfully than we or our collaborators are able to do. Many of our competitors, particularly large pharmaceutical companies, have substantially greater financial, technical and human resources and larger research and development staffs than we do. In addition, academic institutions, government agencies and other public and private organizations conducting research may seek patent protection with respect to potentially competitive products or technologies and may establish exclusive collaborative or licensing relationships with our competitors.

We believe that our ability to compete is dependent, in part, upon our ability to create, maintain and license scientifically advanced technology and upon our and our collaborators’ ability to develop and commercialize pharmaceutical products based on this technology, as well as our ability to attract and retain qualified personnel, obtain patent protection or otherwise develop proprietary technology or processes and secure sufficient capital resources for the expected substantial time period between technological conception and commercial sales of products based upon our technology. The failure by any of our collaborators or us, including our commercial team, in any of those areas may prevent the successful commercialization of our potential drug targets.

Many of our competitors, either alone or together with their collaborative partners, have significantly greater experience than we do in:

● identifying and validating targets;

● screening compounds against targets; and

● undertaking preclinical testing and clinical trials.

Accordingly, our competitors may succeed in obtaining patent protection, identifying or validating new targets or discovering new drug compounds before we do.

Our competitors might develop technologies and drugs that are more effective or less costly than any that are being developed by us or that would render our technology and product candidates obsolete and noncompetitive. In addition, our competitors may succeed in obtaining the approval of the FDA or other regulatory agencies for product candidates more rapidly. Companies that complete clinical trials, obtain required regulatory agency approvals and commence commercial sale of their drugs before us may achieve a significant competitive advantage, including certain patent and FDA marketing exclusivity rights that would delay or prevent our ability to market certain products. Any drugs resulting from our research and development efforts, or from our joint efforts with our existing or future collaborative partners, might not be able to compete successfully with competitors’ existing or future products or obtain regulatory approval in the United States or elsewhere.

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We face and will continue to face intense competition from other companies for commercial and collaborative arrangements with pharmaceutical and biotechnology companies, for establishing relationships with academic and research institutions and for licenses to additional technologies. These competitors, either alone or with their collaborative partners, may succeed in developing technologies or products that are more effective than ours.

Our ability to compete successfully will depend, in part, on our ability to:

● identify and validate targets;

● discover candidate drug compounds that interact with the targets we identify;

● attract and retain scientific and product development personnel;

● enter commercialization agreements for our new drug compounds.

Government Regulation

Government authorities in the United States, at the federal, state and local level, and in other countries and jurisdictions, extensively regulate, among other things, the research, development, testing, manufacture, quality control, approval, packaging, storage, recordkeeping, labeling, advertising, promotion, distribution, marketing, sales, post-approval monitoring and reporting, and import and export of pharmaceutical products. The processes for obtaining regulatory approvals in the United States and in foreign countries and jurisdictions, along with subsequent compliance with applicable statutes and regulations, such as those governing personal information and information security,require the expenditure of substantial time and financial resources.

Review and Approval of Drugs in the United States

In the United States, the FDA approves and regulates drugs under the Federal Food, Drug, and Cosmetic Act (FDCA) and implementing regulations. The failure to comply with requirements under the FDCA and other applicable laws at any time during the product development process, approval process or after approval may subject an applicant and/or sponsor to a variety of administrative or judicial sanctions, including refusal by the FDA to approve pending applications, withdrawal of an approval, imposition of a clinical hold, issuance of warning letters and other types of letters, product recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of government contracts, restitution, disgorgement of profits, or civil or criminal investigations and penalties.

A drug product candidate must be approved by the FDA through the new drug application (NDA). An applicant seeking approval to market and distribute a new drug product in the United States must typically undertake the following:

● review by an FDA advisory committee, if requested by the FDA;

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● payment of user fees and securing FDA approval of the NDA; and

Before an applicant begins testing a compound with potential therapeutic value in humans, the drug candidate enters the preclinical testing stage. Preclinical studies include laboratory evaluation as well as in vitro and animal studies to assess the safety and activity of the drug for initial testing in humans and to establish a rationale for therapeutic use. The results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature and plans for clinical studies, among other things, are submitted to the FDA as part of an IND. Some long-term preclinical testing, such as animal tests of reproductive adverse events and carcinogenicity, and long-term toxicity studies, may continue after the IND is submitted.

In support of the IND, applicants must submit a protocol for each clinical trial and any subsequent protocol amendments. In addition, the results of the preclinical tests, together with manufacturing information, analytical data, any available clinical data or literature, among other things, are submitted to the FDA as part of an IND. The FDA requires a 30-day waiting period after the submission of each IND before clinical trials may begin. At any time during this 30-day period, or thereafter, the FDA may raise concerns or questions about the conduct of the trials as outlined in the IND and impose a clinical hold or partial clinical hold. In this case, the IND sponsor and the FDA must resolve any outstanding concerns before clinical trials can begin or resume. An IRB representing each institution participating in the clinical trial must review and approve the plan for any clinical trial before it commences at that institution, and the IRB must conduct continuing review and reapprove the study at least annually. An IRB can suspend or terminate approval of a clinical trial.

Clinical trials involve the administration of the investigational product to human subjects under the supervision of qualified investigators in accordance with GCP requirements, which include, among other things, the requirement that all research subjects provide their informed consent in writing before their participation in any clinical trial. Human clinical trials are typically conducted in sequential phases, which may overlap or be combined:

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The FDA or the sponsor or the data monitoring committee may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research subjects are being exposed to an unacceptable health risk.

Review and Approval of Drugs in the EU and the UK

Similar rules governing clinical trials to those in place in the United States apply in the EU and the UK. Following the UK’s exit from the EU, commonly referred to as Brexit, and the end of the transition period that was in place until the end of 2020, clinical trials that take place in the UK will be seen by the EMA as trials that have taken place in a “third country” and will only be considered during the course of a marketing authorization application if they are carried out on a basis that is in line with the regulations governing clinical trials in the EU. Clinical trials in the EU must be conducted in accordance with the requirements of the EU Clinical Trials Directive, as implemented in national law by individual member states, and applicable good clinical practice standards. The EU Clinical Trials Directive is due to be replaced with the new EU Clinical Trials Regulation, or EU CTR, at the end of 2021. Should the UK not seek to align its clinical trials regulations with the EU CTR then trials that take place in the UK may carry less weight when applying for a marketing authorization in the EU.

Review of an NDA by the FDA

If clinical trials are successful, the next step in the drug development process is the preparation and submission to the FDA of a NDA. The NDA is the vehicle through which drug applicants formally propose that the FDA approve a new drug for marketing and sale in the United States for one or more indications. The NDA must contain a description of the manufacturing process and quality control methods, as well as results of preclinical tests, toxicology studies, clinical trials and proposed labeling, among other things. The submission of most NDAs is subject to an application user fee and the sponsor of an approved NDA is also subject to annual product and establishment user fees. These fees are typically increased annually.

Following submission of an NDA, the FDA conducts a preliminary review of an NDA to determine whether the application is sufficiently complete to permit substantive review. Once the submission is accepted for filing, the FDA begins an in-depth substantive review. The FDA has agreed to goals to review and act within ten months from filing for standard review NDAs and within six months for NDAs that have been designated for “priority review”.

Before approving an NDA, the FDA typically will inspect the facility or facilities where the product is or will be manufactured. The FDA will not approve an application 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. Additionally, before approving an NDA, the FDA will typically inspect one or more clinical sites to assure compliance with GCP. In addition, as a condition of approval, the FDA may require an applicant to develop a REMS. REMS use risk minimization strategies beyond the professional labeling to ensure that the benefits of the product outweigh the potential risks. To determine whether a REMS is needed, the FDA will consider the size of the population likely to use the product, seriousness of the disease, expected benefit of the product, expected duration of treatment, seriousness of known or potential adverse events, and whether the product is a new molecular entity.

The FDA is required to refer an application for a novel drug to an advisory committee or explain why such referral was not made. Typically, an advisory committee is a panel of independent experts, including clinicians and other scientific experts, that reviews, evaluates and provides a recommendation as to whether the application should be approved and under what conditions. The FDA is not bound by the recommendations of an advisory committee, but it considers such recommendations carefully when making decisions.

On the basis of the FDA’s evaluation of the NDA and accompanying information, including the results of the inspection of the manufacturing facilities, the FDA may issue an approval letter or a complete response letter. An approval letter authorizes commercial marketing of the product with specific prescribing information for specific indications. A complete response letter generally outlines the deficiencies in the submission and may require substantial additional testing or information in order for the FDA to reconsider the application. If and when those deficiencies have been addressed to the FDA’s satisfaction in a resubmission of the NDA, the FDA will issue an approval letter.

If the FDA approves a product, it may limit the approved indications for use for the product, require that contraindications, warnings or precautions be included in the product labeling, require that post-approval studies, including Phase 4 clinical trials, be conducted to further assess the drug’s safety after approval, require testing and surveillance programs to monitor the product after commercialization, or impose other conditions, including distribution

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restrictions or other risk management mechanisms, including REMS, which can materially affect the potential market and profitability of the product. The FDA may prevent or limit further marketing of a product based on the results of post-market studies or surveillance programs. After approval, many types of changes to the approved product, such as adding new indications, manufacturing changes and additional labeling claims, are subject to further testing requirements and FDA review and approval.

Post-Approval Requirements

Drugs manufactured or distributed pursuant to FDA approvals are subject to pervasive and continuing regulation by the FDA, including, among other things, requirements relating to recordkeeping, periodic reporting, product sampling and distribution, advertising and promotion and reporting of adverse experiences with the product. After approval, most changes to the approved product, such as adding new indications or other labeling claims, are subject to prior FDA review and approval. In addition, drug manufacturers and other entities involved in the manufacture and distribution of approved drugs are required to register their establishments with the FDA and state agencies, and are subject to periodic unannounced inspections by the FDA and these state agencies for compliance with cGMP requirements. Changes to the manufacturing process are strictly regulated and often require prior FDA approval before being implemented. FDA regulations also require investigation and correction of any deviations from cGMP and impose reporting and documentation requirements upon the sponsor and any third-party manufacturers that the sponsor may decide to use. Accordingly, manufacturers must continue to expend time, money, and effort in the area of production and quality control to maintain cGMP compliance.

Once an approval is granted, the FDA may withdraw the approval if compliance with regulatory requirements and standards is not maintained or if problems occur after the product reaches the market. Later discovery of previously unknown problems with a product, including adverse events of unanticipated severity or frequency, or with manufacturing processes, or failure to comply with regulatory requirements, may result in revisions to the approved labeling to add new safety information; imposition of post-market studies or clinical trials to assess new safety risks; or imposition of distribution or other restrictions under a REMS program.

The FDA strictly regulates marketing, labeling, advertising and promotion of products that are placed on the market. Drugs may be promoted only for the approved indications and in accordance with the provisions of the approved label. 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 uses 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.

In addition, the distribution of prescription pharmaceutical products is subject to the Prescription Drug Marketing Act, or PDMA, and its implementing regulations, as well as the Drug Supply Chain Security Act, or DSCA, which regulate the distribution and tracing of prescription drugs and prescription drug samples at the federal level, and set minimum standards for the regulation of drug distributors by the states. The PDMA, its implementing regulations and state laws limit the distribution of prescription pharmaceutical product samples, and the DSCA imposes requirements to ensure accountability in distribution and to identify and remove counterfeit and other illegitimate products from the market.

Orphan Drug Designation and Exclusivity

Under the Orphan Drug Act, the FDA may designate a drug product as an “orphan drug” if it is intended to treat a rare disease or condition, generally meaning that it affects fewer than 200,000 individuals in the United States, or more in cases in which there is no reasonable expectation that the cost of developing and making a drug product available in the United States for treatment of the disease or condition will be recovered from sales of the product. A company must request orphan drug designation before submitting an NDA for the drug and rare disease or condition. Orphan drug designation does not shorten the goal dates for the regulatory review and approval process, although it does convey certain advantages such as tax benefits and exemption from the application fee.

If a product with orphan designation receives the first FDA approval for the disease or condition for which it has such designation, the product generally will receive orphan drug exclusivity. Orphan drug exclusivity means that the

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FDA may not approve another sponsor’s marketing application for the same drug for the same indication for seven years, except in certain limited circumstances. Orphan exclusivity does not block the approval of a different drug for the same rare disease or condition, nor does it block the approval of the same drug for different indications. If a drug designated as an orphan drug ultimately receives marketing approval for an indication broader than what was designated in its orphan drug application, it may not be entitled to exclusivity. Orphan exclusivity will not bar approval of another product under certain circumstances, including if a subsequent product with the same drug for the same indication is shown to be clinically superior to the approved product on the basis of greater efficacy or safety, or providing a major contribution to patient care, or if the company with orphan drug exclusivity is not able to meet market demand.

Pharmaceutical Coverage, Pricing and Reimbursement

In the United States and markets in other countries, patients who are prescribed treatments for their conditions and providers performing the prescribed services generally rely on third-party payors to reimburse all or part of the associated healthcare costs. Third-party payors include federal and state government health programs such as Medicare and Medicaid, commercial health insurers, managed care organizations, and other organizations. Significant uncertainty exists as to the coverage and reimbursement status of products approved by the FDA and other government authorities. For example, there have been several recent U.S. Congressional inquiries and proposed federal legislation designed to, among other things, bring more transparency to drug pricing, review the relationship between pricing and manufacturer patient programs, reduce the cost of drugs under Medicare, and reform government program reimbursement methodologies for drugs. In the United States, some of these proposals at the federal level include directing Medicare to negotiate directly with manufacturers for the costliest drugs; various Medicare Part D and Medicaid reforms; price reporting transparency; importation rulemaking; an international pricing index proposal to require additional discounts to Medicare, as well as a proposal requiring manufacturers to pay a rebate to the federal government if the price of a Medicare Part B or Part D drug increases more than the rate of inflation. For example, certain proposals have been contemplated that would implement a cap on annual price increases for certain drugs covered under Medicare at the rate of inflation or require the respective manufacturers to pay a rebate. There has also been advocacy for increasing the Medicaid drug rebates cap, currently at 100% of a drug's average manufacturer price or removing such cap in its entirety. At the state level, legislatures have increasingly passed legislation and implemented 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 transparency measures, and, in some cases, to encourage importation from other countries and bulk purchasing. Thus, even if a product candidate is approved, sales of the product will depend, in part, on the extent to which third-party payors provide coverage and establish adequate reimbursement levels for the product. It is likely that additional state and federal healthcare reform measures will be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand for a pharmaceutical manufacturer’s products or additional pricing pressure.

In order to secure coverage and reimbursement for any product that might be approved for sale, a company may need to conduct expensive pharmacoeconomic studies in order to demonstrate the medical necessity and cost-effectiveness of the product, in addition to the costs required to obtain FDA or other comparable marketing approvals. Nonetheless, product candidates may not be considered medically necessary or cost effective. A decision by a third-party payor not to cover a product candidate could reduce physician utilization once the product is approved and have an adverse effect on sales, results of operations and financial condition. Additionally, 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 drug product does not assure that other payors will also provide coverage and reimbursement for the product, and the level of coverage and reimbursement can differ significantly from payor to payor.

The containment of healthcare costs also has become a priority of federal, state and foreign governments and the prices of drugs have been a focus in this effort. Governments have shown significant interest in implementing cost-containment programs, including price controls, restrictions on reimbursement and requirements for substitution of generic products. Adoption of price controls and cost-containment measures, and adoption of more restrictive policies in jurisdictions with existing controls and measures, could further limit a company’s revenue generated from the sale of any approved products. 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 a company or its collaborators receive marketing approval, less favorable coverage policies and reimbursement rates may be implemented in the future.

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Healthcare and Privacy Law and Regulation

Healthcare providers and third-party payors play a primary role in the recommendation and prescription of drug products that are granted marketing approval. Arrangements with providers, consultants, third-party payors and customers are subject to broadly applicable fraud and abuse, anti-kickback, false claims laws, reporting of payments to physicians and teaching physicians and patient privacy laws and regulations and other healthcare laws and regulations that may constrain business and/or financial arrangements. Restrictions under applicable healthcare laws and regulations, include the following:

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Some state, local and foreign laws require pharmaceutical companies to comply with the pharmaceutical industry’s voluntary compliance guidelines and the relevant compliance guidance promulgated by the federal government, restrict payments that may be made to healthcare providers and other potential referral sources, and/or require drug manufacturers to report information related to payments and transfers of value made to physicians and other health care providers or entities or marketing expenditures. In addition, there are state and local laws that require registration of sales representatives; state laws that require drug manufacturers to report information related to drug pricing; data privacy and security laws and regulations in foreign jurisdictions that may be more stringent than those in the United States (such as the European Union (E.U.), which adopted the General Data Protection Regulation (GDPR), which became effective in May 2018); federal and state laws governing the privacy and security of personal information (including health information) many of which differ from each other in significant ways and may not have the same effect, thus complicating compliance efforts; and state laws related to insurance fraud in the case of claims involving private insurers.

Efforts to ensure that our business arrangements will comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental and enforcement authorities will conclude that our business practices may not comply with current or future statutes, regulations or case law interpreting applicable fraud and abuse or other healthcare laws and regulations. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business, including the imposition of civil, criminal and administrative penalties, damages, disgorgement, monetary fines, individual imprisonment, additional reporting obligations and oversight if we become subject to a corporate integrity agreement or other agreement to resolve allegations of non-compliance with these laws, possible exclusion from participation in federal healthcare programs, contractual damages, reputational harm, diminished profits and future earnings, and curtailment or restructuring of our operations, any of which could adversely affect our ability to operate our business and our results of operations.

Healthcare Reform

The United States and state governments continue to propose and pass legislation designed to reduce the cost of healthcare. In March 2010, the United States Congress enacted the Affordable Care Act which included changes to the coverage and payment for drug products under government health care programs. There remain judicial and Congressional challenges to certain aspects of the Affordable Care Act, as well as efforts by the Trump administration to repeal or replace certain aspects of the Affordable Care Act. For example, President Trump signed two Executive Orders designed to delay the implementation of certain provisions of the Affordable Care Act or otherwise circumvent some of the requirements for health insurance mandated by the Affordable Care Act. Concurrently, Congress has considered legislation that would repeal or repeal and replace all or part of the Affordable Care Act. While Congress has not passed comprehensive repeal legislation, several bills affecting the implementation of certain taxes under the Affordable Care Act have been enacted. The Tax Cuts and Jobs Act of 2017 includes a provision repealing, effective January 1, 2019, the tax-based shared responsibility payment imposed by the Affordable Care Act on certain individuals who fail to maintain qualifying health coverage for all or part of a year that is commonly referred to as the “individual mandate”. In addition, the 2020 federal spending package permanently eliminated, effective January 1, 2020, the Affordable Care Act’s mandated “Cadillac” tax on high-cost employer-sponsored health coverage and medical device tax and, effective January 1, 2021, also eliminated the health insurer tax. The Bipartisan Budget Act of 2018 (BBA) among other things, amended the Affordable Care Act, effective January 1, 2019, to increase from 50% to 70% the point-of-sale discount that is owed by pharmaceutical manufacturers who participate in Medicare Part D and to close the coverage gap in most Medicare drug plans, commonly referred to as the “donut hole.” In December 2018, CMS published a new final rule permitting further collections and payments to and from certain Affordable Care Act qualified health plans and health insurance

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issuers under the Affordable Care Act risk adjustment program in response to the outcome of federal district court litigation regarding the method CMS uses to determine this risk adjustment. On December 14, 2018, a U.S. District Court Judge in the Northern District of Texas ruled that the individual mandate is a critical and inseverable feature of the Affordable Care Act, and because it was repealed as part of the Tax Cuts and Job Act of 2017, the remaining provisions of the Affordable Care Act are invalid as well. Additionally, on December 18, 2019, the U.S. Court of Appeals for the 5th Circuit upheld the District Court ruling that the individual mandate was unconstitutional and remanded the case back to the District Court to determine whether the remaining provisions of the Affordable Care Act are invalid as well. The U.S. Supreme Court is currently reviewing this case, but it is unknown when a decision will be reached. Although the U.S. Supreme Court has not yet ruled on the constitutionality of the Affordable Care Act, on January 28, 2021, President Biden issued an executive order to initiate a special enrollment period from February 15, 2021 through May 15, 2021 for purposes of obtaining health insurance coverage through the Affordable Care Act marketplace. The executive order also instructs certain governmental agencies to review and reconsider their existing policies and rules that limit access to healthcare, including among others, reexamining Medicaid demonstration projects and waiver programs that include work requirements, and policies that create unnecessary barriers to obtaining access to health insurance coverage through Medicaid or the Affordable Care Act. It is unclear how the Supreme Court, other such litigation, the healthcare reform measures of the Biden administration will impact the Affordable Care Act.

Other legislative changes have been proposed and adopted in the United States since the Affordable Care Act was enacted. In August 2011, the Budget Control Act of 2011, among other things, created measures for spending reductions by Congress. A Joint Select Committee on Deficit Reduction, tasked with recommending a targeted deficit reduction of at least $1.2 trillion for the years 2013 through 2021, was unable to reach required goals, thereby triggering the legislation’s automatic reduction to several government programs. This includes aggregate reductions of Medicare payments to providers of 2% per fiscal year, which went into effect in April 2013, and, due to subsequent legislative amendments, will remain in effect through 2030, unless additional Congressional action is taken. However, COVID-19 relief support legislation suspended the 2% Medicare sequester from May 1, 2020 through March 31, 2021.In January 2013, President Obama signed into law the American Taxpayer Relief Act of 2012 (ATRA), which, among other things, further reduced Medicare payments to several providers, including hospitals and cancer treatment centers, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

In addition, there has been heightened governmental scrutiny in the United States of pharmaceutical pricing practices in light of the rising cost of prescription drugs and biologics. Such scrutiny has resulted in several recent congressional inquiries and proposed and enacted federal and state legislation designed to, among other things, bring more transparency to product pricing, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for products. At the federal level, the Trump administration used several means to propose or implement drug pricing reform, including through federal budget proposals, executive orders and policy initiatives. For example, on July 24, 2020 and September 13, 2020, the Trump administration announced several executive orders related to prescription drug pricing that attempt to implement several of the administration’s proposals. The FDA also released a final rule, effective November 30, 2020, implementing a portion of the importation executive order providing guidance for states to build and submit importation plans for drugs from Canada. Further, on November 20, 2020, HHS finalized a regulation removing safe harbor protection for price reductions from pharmaceutical manufacturers to plan sponsors under Part D, either directly or through pharmacy benefit managers, unless the price reduction is required by law. The implementation of the rule has been delayed by the Biden administration from January 1, 2022 to January 1, 2023 in response to ongoing litigation. The rule also creates a new safe harbor for price reductions reflected at the point-of-sale, as well as a new safe harbor for certain fixed fee arrangements between pharmacy benefit managers and manufacturers, the implementation of which have also been delayed pending review by the Biden administration until March 22, 2021. On November 20, 2020, CMS issued an interim final rule implementing President Trump’s Most Favored Nation executive order, which would tie Medicare Part B payments for certain physician-administered drugs to the lowest price paid in other economically advanced countries, effective January 1, 2021. On December 28, 2020, the United States District Court in Northern California issued a nationwide preliminary injunction against implementation of the interim final rule. Further, certain proposals have been contemplated that would implement a cap on annual price increases for certain drugs covered under Medicare at the rate of inflation or require the respective manufacturers to pay a rebate. There has also been advocacy for increasing the Medicaid drug rebates cap, currently at 100% of a drug's average manufacturer price or removing such cap in its entirety. However, it is unclear whether the Biden administration will work to reverse measures taken during the Trump administration or pursue similar policy initiatives. At the state level, legislatures have increasingly passed legislation and

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implemented 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 transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing.

Outside the United States, ensuring adequate coverage and payment for our products will face challenges. Pricing of prescription pharmaceuticals is subject to governmental control in many countries. Pricing negotiations with governmental authorities can extend well beyond the receipt of regulatory approval for a product and may require us to conduct a clinical trial that compares the cost effectiveness of our product candidates or products to other available therapies. The conduct of such a clinical trial could be expensive and result in delays in our commercialization efforts. Third-party payors are challenging the prices charged for medical products and services, and many third-party payors limit reimbursement for newly approved health care products. Recent budgetary pressures in many E.U. countries are also causing governments to consider or implement various cost-containment measures, such as price freezes, increased price cuts and rebates. If budget pressures continue, governments may implement additional cost-containment measures. Cost-control initiatives could decrease the price we might establish for products that we may develop or sell, which would result in lower product revenues or royalties payable to us. There can be no assurance that any country that has price controls or reimbursement limitations for pharmaceutical products will allow favorable reimbursement and pricing arrangements for any of our products. Further, it is possible that additional governmental action is taken in response to the COVID-19 pandemic.

Manufacturing and Raw Materials

We currently do not have the manufacturing capabilities or experience necessary to produce TAVALISSE or any product candidates for clinical trials, including fostamatinib in AIHA, our IRAK 1/4 inhibitor program and our RIP1 inhibitor program. We do not own or operate manufacturing or distribution facilities or resources for clinical or commercial production and distribution of our product for commercial use or for preclinical and clinical trials. We assign internal personnel to manage and oversee third parties working on our behalf under contract. These third parties manufacture raw materials, the active pharmaceutical ingredient (API) and finished drug product for commercial distribution and for use in clinical studies. We currently rely on and will continue to rely on these third-party contract manufacturers to produce sufficient quantities of our products.

Employees

As of December 31, 2020, we had 169 full-time employees. None of our employees are represented by a collective bargaining arrangement, and we believe our relationship with our employees is good. Recruiting and retaining experienced and qualified sales and marketing personnel to successfully commercialize our product and scientific personnel to continue to perform research and development work in the future will be critical to our business success. We may not be able to attract and retain personnel on acceptable terms given the competition among pharmaceutical and biotechnology companies, academic and research institutions and government agencies for experienced scientists.

Scientific and Medical Advisors

We utilize scientists, key opinion leaders and physicians to advise us on scientific and medical matters as part of our ongoing commercialization activities and research and product development efforts, including experts in clinical trial design, preclinical development work, chemistry, biology, immunology, oncology and immuno-oncology. Certain of our consultants receive non-employee options to purchase our common stock and certain of our scientific and medical advisors receive honorarium for time spent assisting us.

Corporate Information

Our principal executive office is located at 1180 Veterans Boulevard, South San Francisco, California 94080. Our telephone number is (650) 624-1100.

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Available Information

We electronically file with the Securities and Exchange Commission (SEC) our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K and amendments to the reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act. We make available free of charge on or through our website at www.rigel.com, copies of these reports as soon as reasonably practicable after we electronically file these reports with, or furnish them to, the SEC. The information found on our website is not part of or incorporated by reference into this Annual Report on Form 10-K.

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

Item 1A. Risk Factors

In evaluating our business, you should carefully consider the following risks, as well as the other information contained in this Annual Report on Form 10-K. These risk factors could cause our actual results to differ materially from those contained in forward-looking statements we have made in this Annual Report on Form 10-K and those we may make from time to time. If any of the following risks actually occurs, our business, financial condition and operating results could be harmed. The risks and uncertainties described below are not the only ones facing us. Additional risks and uncertainties not presently known to us, or that we currently see as immaterial, may also harm our business.

Our prospects are highly dependent on our first commercial product, TAVALISSE (fostamatinib disodium hexahydrate). To the extent that the commercial success of TAVALISSE in the United States is diminished or is not commercially successful, our business, financial condition and results of operations may be adversely affected, and the price of our common stock may decline.

TAVALISSE is our only drug that has been approved for sale in the United States and Europe for patients with chronic ITP. We are focusing a significant portion of our activities and resources on fostamatinib, and we believe our prospects are highly dependent on, and a significant portion of the value of our company relates to, our ability to sustain successful commercialization of TAVALISSE in the United States. We have entered into an exclusive commercialization agreement with Grifols to commercialize fostamatinib in Europe.

Sustained successful commercialization of TAVALISSE is subject to many risks and uncertainties, including the impact of the COVID-19 pandemic on the successful commercialization in the United States, as well as the successful commercialization efforts for TAVLESSE in Europe through our partner, Grifols. Prior to TAVALISSE, we have never, as an organization, launched or commercialized a product, and there is no guarantee that we will be able to continue to do so successfully with fostamatinib for its approved indication. In addition, our partner, Grifols, is responsible for the commercial launch of TAVLESSE in Europe. Although Grifols launched TAVLESSE in Germany and the UK in July 2020, we cannot be certain if Grifols will be successful in launching TAVLESSE in Italy, Spain and France, and additional territories in Europe that it may pursue, or continue to be successful in commercializing and marketing in any such regions, including Germany and the UK. There are numerous examples of unsuccessful product launches and failures to meet high expectations of market potential, including by pharmaceutical companies with more experience and resources than us.

As we continue to build out our commercial team, there are many factors that could cause the commercialization of TAVALISSE to be unsuccessful, including a number of factors that are outside our control. The commercial success of TAVALISSE depends on the extent to which patients and physicians accept and adopt TAVALISSE for patients with chronic ITP who have had an insufficient response to a previous treatment. We also do not know how physicians, patients and payors will respond to our future price increases of TAVALISSE. Physicians may not prescribe TAVALISSE and patients may be unwilling to use TAVALISSE if coverage is not provided or reimbursement is inadequate to cover a significant portion of the cost. TAVALISSE competes, and may in the future compete, with currently existing therapies, including generic drugs, and products currently under development. Our competitors, particularly large pharmaceutical companies, may deploy more resources to market, sell and distribute their products. If our efforts are not appropriately resourced to adequately promote our products, the commercial potential of our sales

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may be diminished. Additionally, any negative development for fostamatinib in clinical development in additional indications, such as in the clinical trials of fostamatinib in COVID-19 patients, may adversely impact the commercial results and potential of fostamatinib. Thus, significant uncertainty remains regarding the commercial potential of fostamatinib.

Market acceptance of fostamatinib will depend on a number of factors, including:

● the clinical indications for which the product is approved;

● impacts due to the evolving effects of the COVID-19 pandemic;

RIGL US Equity

RIGL · 10-K · period ended 2020-12-31

Item 1. Business

Item 1A. Risk Factors

RIGL US Equity☆

RIGL · 10-K · period ended 2020-12-31

Item 1. Business

Item 1A. Risk Factors

RIGL US Equity