UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.001 par value ANAB The Nasdaq Stock Market LLC FORM 10-Q ☒ Quarterly Report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended June 30, 2020 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to . Commission File Numbe ...

Revenue and Collaboration - Collaboration revenue for Q1 2020 was $15.0 million, compared to $0.0 million in Q1 2019, driven by two milestones related to dostarlimab[91]. - The company has received approximately $100.0 million in cash receipts from collaborations to date[80]. - The company expects marketing approval for dostarlimab by the FDA for endometrial cancer during 2020[80]. Research and Development Expenses - Research and development expenses increased to $21.0 million in Q1 2020 from $20.6 million in Q1 2019, primarily due to a $0.5 million rise in clinical expenses[92]. - External costs for the etokimab program were $7.9 million in Q1 2020, up from $7.5 million in Q1 2019, reflecting an increase of $0.4 million[95]. - ANB019 external costs rose to $5.2 million in Q1 2020 from $5.0 million in Q1 2019, an increase of $0.2 million[95]. - ANB030 external costs decreased significantly to $0.7 million in Q1 2020 from $1.5 million in Q1 2019, a decrease of $0.8 million[95]. - Total external costs for the company were $16.4 million in Q1 2020, compared to $16.0 million in Q1 2019, reflecting a modest increase of $0.4 million[95]. - The company anticipates interim top-line data from the ECLIPSE trial of etokimab in Q3 2020[75]. Financial Performance - The ongoing COVID-19 pandemic may negatively impact the company's financial results and liquidity in fiscal 2020[82]. - General and administrative expenses increased to $4.3 million for Q1 2020 from $4.1 million in Q1 2019, primarily due to a $0.2 million rise in personnel costs and insurance expenses[96]. - Interest expense decreased to $0.0 million in Q1 2020 from $0.3 million in Q1 2019 due to the final payment on Term Loans[97]. - Interest income fell to $1.9 million in Q1 2020 from $3.0 million in Q1 2019, attributed to lower interest rates and decreased investment balances[98]. - Cash, cash equivalents, and investments totaled $412.7 million as of March 31, 2020, down from $428.5 million as of December 31, 2019[104]. - Net cash used in operating activities was $15.1 million in Q1 2020, compared to $16.1 million in Q1 2019, reflecting a reduced net loss[106]. - Net cash provided by investing activities was $10.8 million in Q1 2020, up from $9.7 million in Q1 2019, primarily due to investment maturity timing[107]. Future Financial Outlook - The company expects general and administrative expenses to rise due to costs associated with being publicly traded, including legal and compliance expenses[96]. - Future minimum annual obligations under non-cancellable operating lease commitments are $0.7 million for the remainder of fiscal years ending 2020 and 2021[110]. - The company has received an aggregate of $738.5 million since inception, with $412.7 million available as of March 31, 2020, to fund operations[100]. - The company may seek additional financing through equity or debt financings or collaborations, with uncertainty regarding the ability to obtain such financing on reasonable terms[102].

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ______________________________________ FORM 10-K ______________________________________ ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number: 001-37985 ______________________________________ ANAPTYSBIO, INC. (Ex ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.001 par value ANAB The Nasdaq Stock Market LLC Non-accelerated Filer ☐ Smaller Reporting Company ☐ Emerging Growth Company ☐ FORM 10-Q ☒ Quarterly Report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended September 30, 2019 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securi ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.001 par value ANAB The Nasdaq Stock Market LLC Non-accelerated Filer ☐ Smaller Reporting Company ☐ Emerging Growth Company ☐ FORM 10-Q ☒ Quarterly Report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended June 30, 2019 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.001 par value ANAB The Nasdaq Stock Market LLC FORM 10-Q x Quarterly Report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the quarterly period ended March 31, 2019 OR ¨ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 For the transition period from to . Commission File Numb ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 ______________________________________ FORM 10-K ______________________________________ x ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2018 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM TO Commission File Number: 001-37985 ______________________________________ ANAPTYSBIO, INC. (Ex ...