Description of Business

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 product approved by the US Food and Drug Administration (FDA) is TAVALISSE® (fostamatinib disodium hexahydrate) tablets, the only approved oral spleen tyrosine kinase (SYK) inhibitor, for the treatment of adult patients with chronic immune thrombocytopenia (ITP) who have had an insufficient response to a previous treatment. The product is also commercially available in Europe, United Kingdom (UK) (TAVLESSE) and Canada (TAVALISSE) for the treatment of chronic ITP in adult patients.

Our portfolio also includes olutasidenib, an oral, small molecule inhibitor of mutated isocitrate dehydrogenase-1 (mIDH1) being investigated for the treatment of acute myeloid leukemia (AML) and other malignancies. We in-licensed olutasidenib from Forma Therapeutics, Inc. (Forma) with exclusive, worldwide rights to develop, manufacture, and commercialize the investigational drug.

We conducted a Phase 3 clinical trial evaluating fostamatinib for the treatment of warm autoimmune hemolytic anemia (wAIHA), and recently announced that we do not expect to file a supplemental New Drug Application (sNDA) for this indication at this time considering the top-line data results and the guidance received from the FDA. We recently announced the completion of the FOCUS Phase 3 clinical trial of fostamatinib for the treatment of hospitalized high-risk patients with COVID-19. Fostamatinib is also currently being studied in a National Institute of Health (NIH)/National Heart, Lung, and Blood Institute (NHLBI) sponsored Accelerating COVID-19 Therapeutic Inventions and Vaccines (ACTIV-4) Phase 3 trial (ACTIV-4 Host Tissue Trial) for the treatment of COVID-19 in hospitalized patients.

Our other clinical programs include our interleukin receptor-associated kinase (IRAK) inhibitor program and a receptor-interacting serine/threonine-protein kinase (RIPK1) inhibitor program in clinical development with partner Eli Lilly and Company (Lilly). In addition, we have product candidates in clinical development with partners BerGenBio ASA (BerGenBio) and Daiichi Sankyo (Daiichi).

Basis of Presentation

Our accompanying unaudited condensed financial statements have been prepared in accordance with United States generally accepted accounting principles (US GAAP), for interim financial information and pursuant to the instructions to Form 10-Q and Article 10 of Regulation S-X of the Securities Act of 1933, as amended (Securities Act). Accordingly, they do not include all the information and notes required by US GAAP for complete financial statements. These unaudited condensed financial statements include only normal and recurring adjustments that we believe are necessary to fairly state our financial position and the results of our operations and cash flows. Interim-period results are not necessarily indicative of results of operations or cash flows for a full-year or any subsequent interim period. The balance sheet as of December 31, 2021 has been derived from audited financial statements at that date but does not include all disclosures required by US GAAP for complete financial statements. Because certain disclosures required by US GAAP for complete financial statements are not included herein, these interim unaudited condensed financial statements and the notes accompanying them should be read in conjunction with our audited financial statements and the notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on March 1, 2022.

Use of Estimates

The preparation of financial statements in conformity with US GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. We base our

estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances. Actual results could differ from these estimates.

Significant Accounting Policies

Our significant accounting policies are described in “Note 1 – Description of Business and Summary of Significant Accounting Policies” to our “Notes to Financial Statements” contained in “Part II, Item 8, Financial Statements and Supplementary Data” of our Annual Report on Form 10-K for the year ended December 31, 2021. There have been no material changes to these accounting policies, except for our accounting associated with our in-license agreement with Forma as discussed in detail in “Note 4 – Sponsored Research and License Agreements”.

Liquidity

As of September 30, 2022, we had approximately $81.6 million in cash, cash equivalents and short-term investments. Since inception, we have financed our operations primarily through sales of equity securities, debt financing, contract payments under our collaboration agreements and from product sales.

Based on our current operating plan, we believe that our existing cash, cash equivalents, and short-term investments will be sufficient to fund our expenses and capital expenditure requirements for at least the next 12 months from the date of issuance of this Form 10-Q.

Recently Issued Accounting Standards

No new accounting guidance adopted during the period. Recently issued accounting guidance is not applicable or did not have, or is not expected to have, a material impact to us.