Clinical Trials and Drug Development - Catalyst Biosciences is initiating a Phase 3 clinical trial for MarzAA, targeting approximately 230 bleeding episodes in about 75 patients with Hemophilia A or B with inhibitors[73]. - The Phase 2b study for DalcA showed effective prophylaxis with FIX activity levels ranging from 14% to 28% and zero bleeds, with a half-life of 70 to 112 hours[79]. - MarzAA has demonstrated the potential for a safety profile comparable to NovoSeven when used in combination with Hemlibra, providing a subcutaneous rescue therapy option[77]. - The company completed two large-scale GMP batches of MarzAA sufficient to support the Phase 3 clinical trial[86]. - Catalyst is optimizing its Factor IX gene therapy construct CB 2679d-GT, which has shown 2-fold to 3-fold higher activity compared to the Padua variant in preclinical studies[80]. - The company is experiencing operational challenges due to the COVID-19 pandemic, which may impact clinical trial timelines and patient enrollment[90]. Financial Performance - The company reported a net loss of $4.1 million for the three months ended March 31, 2020, compared to a net loss of $15.1 million for the same period in 2019, representing a 73% decrease in net loss[93][111]. - As of March 31, 2020, the company had an accumulated deficit of $262.6 million and cash, cash equivalents, and short-term investments totaling $104.5 million[93][118]. - License and collaboration revenue for the three months ended March 31, 2020, was $16.4 million, all derived from the Biogen Agreement[95][112]. - Total operating expenses increased by 36% to $21.4 million for the three months ended March 31, 2020, compared to $15.7 million in the same period of 2019[111]. - Research and development expenses rose to $13.3 million for the three months ended March 31, 2020, up from $12.0 million in 2019, marking a 10% increase[100][114]. - The company expects to incur significant expenses and increasing operating losses for at least the next several years as it continues development and seeks regulatory approval for its drug candidates[94]. Cash Flow and Financing - Cash used in operating activities was $4.8 million for the three months ended March 31, 2020, compared to $14.96 million in the same period of 2019[120]. - The company has committed to a total of $10.7 million in payments to AGC for manufacturing development activities, with $3.4 million outstanding as of March 31, 2020[104]. - Interest and other income increased to $1.0 million for the three months ended March 31, 2020, compared to $0.6 million in 2019, primarily due to a $0.7 million payment from a prior asset sale[116]. - The company plans to fund future losses through equity and/or debt financings, with effective registration statements allowing for the sale of up to $200.0 million in securities[119]. - Cash provided by investing activities for Q1 2020 was $27.4 million, mainly from $33.5 million in proceeds from maturities of investments[123]. - Cash provided by financing activities for Q1 2020 was $32.4 million, due to $32.0 million in net proceeds from the issuance of common stock[125]. - Cash provided by financing activities for Q1 2019 was $0.1 million, entirely from the issuance of common stock related to the Employee Stock Purchase Plan[126]. - As of March 31, 2020, the company had cash and cash equivalents and short-term investments totaling $104.5 million[130]. Market Risks and Accounting Policies - The company does not have any off-balance sheet arrangements[127]. - The company is exposed to market risks, particularly interest income sensitivity in its investment portfolio[129]. - Future investment income may fall short of expectations due to changes in interest rates[129]. - The short-term nature of the instruments in the portfolio minimizes the impact of sudden changes in market interest rates[130]. - There have been no significant changes to critical accounting policies since December 31, 2019[128].

Financial Performance - The company reported a net loss of $55.2 million for the year ended December 31, 2019, compared to a net loss of $30.1 million for the year ended December 31, 2018, resulting in an accumulated deficit of $258.5 million as of December 31, 2019[297]. - Net loss for 2019 was $55.2 million, compared to a net loss of $30.1 million in 2018, representing an increase of 84%[318]. - Cash used in operating activities was $43.6 million in 2019, up from $28.6 million in 2018, reflecting a significant increase in net loss[321]. - Interest and other income decreased by 44% to $2.1 million in 2019 from $3.8 million in 2018, primarily due to the absence of significant milestone payments[315]. Research and Development - Research and development expenses for the year ended December 31, 2019, totaled $43.9 million, significantly increasing from $21.5 million in 2018, with clinical manufacturing costs rising from $12.2 million to $26.1 million[301]. - Research and development expenses increased by 104% to $43.9 million in 2019 from $21.5 million in 2018, primarily due to increased manufacturing activities and personnel-related expenses[312]. - The company expects research and development expenses to increase materially in 2020 due to costs associated with clinical trials and manufacturing[313]. - The company completed a Phase 1/2 SQ dosing trial for DalcA, achieving protective Factor IX activity levels of 12-30% with no reported serious adverse events[288]. - MarzAA, the company's most advanced product candidate, is currently in a SQ Phase 1 study to evaluate its pharmacokinetics and pharmacodynamics, with interim data indicating target levels consistent with treating a bleed[286]. Collaborations and Funding - The company entered into a collaboration agreement with Biogen, receiving a $15 million upfront payment and being eligible for up to $340 million in milestone payments for the development of anti-C3 proteases[290]. - The company raised approximately $32 million from the sale of 5,307,692 shares of common stock at $6.50 per share in February 2020[295]. - The company plans to fund future losses and capital needs through equity and/or debt financings, with effective registration statements allowing for the sale of up to $200.0 million in securities[319]. Cash and Investments - As of December 31, 2019, the company had cash, cash equivalents, and short-term investments totaling $76.9 million[297]. - Cash provided by investing activities was $27.4 million in 2019, primarily due to $157.4 million in proceeds from maturities of investments[324]. - As of December 31, 2019, the company had $76.9 million in cash, cash equivalents, and short-term investments, with an accumulated deficit of $258.5 million[318]. Operating Expenses - General and administrative expenses rose by 9% to $13.4 million in 2019 from $12.4 million in 2018, driven by higher personnel-related costs[314]. - The company expects to incur significant expenses and increasing operating losses for at least the next several years as it continues clinical development and seeks regulatory approval for its drug candidates[298]. Manufacturing and Agreements - The company has a long-term development and manufacturing services agreement with AGC Biologics for drug substance manufacturing, successfully completing a GMP batch of MarzAA to support future studies[292]. - The company has firm work orders totaling $12.4 million with AGC for the manufacture of MarzAA and DalcA to support clinical trials, with $4.6 million still outstanding[304]. - Contract revenue decreased to $0.0 million in 2019 from $0.01 million in 2018, a decline of 100% due to the end of a collaboration agreement[311]. Lease Accounting - The company adopted the new lease accounting standard ASC 842 on January 1, 2019, using the optional transition method, which does not restate comparative financial information[344]. - Operating lease liabilities and corresponding right-of-use assets are recorded based on the present value of lease payments over the expected lease term[345]. - The company utilizes its incremental borrowing rate for lease contracts, as the interest rate implicit in lease contracts is typically not readily determinable[345]. - Lease and non-lease components are combined as a single component, with lease expense recognized over the expected term on a straight-line basis[346]. - Operating leases are recognized on the balance sheet as right-of-use assets and operating lease liabilities, eliminating the recognition of deferred rent[346].

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q (Mark One) ☒ 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 SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number: 000-51173 Catalyst Biosciences, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 56-2020050 (State or Other ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Catalyst Biosciences, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 56-2020050 (State or Other Jurisdiction of Incorporation or Organization) 611 Gateway Blvd., Suite 710 South San Francisco, California 94080 (Address of Principal Executive Offices) (Zip Code) (I.R.S. Employer Identification No.) For the ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION (Mark One) ☒ 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 number: 000-51173 Catalyst Biosciences, Inc. (Exact Name of Registrant as Specified in its Charter) Washington, D.C. 20549 Form 10-Q Indicate by check mark whether the regi ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K (Mark One) ☒ 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: 000-51173 Catalyst Biosciences, Inc. (Exact Name of Registrant as Specified in its Charter) Delaware 56-2020050 (State or Other Jurisdic ...