TABLE OF CONTENTS

As filed with the Securities and Exchange Commission on December 21, 2018

October 24, 2023

Registration No. 333-            

333-273395

UNITED STATES


SECURITIES AND EXCHANGE COMMISSION

WASHINGTON,

Washington, D.C. 20549


PRE-EFFECTIVE AMENDMENT NO. 2
TO
FORMS-3


REGISTRATION STATEMENT


UNDER


THE SECURITIES ACT OF 1933

Catalyst Biosciences, Inc.

CATALYST BIOSCIENCES, INC.
(Exact name of registrant as specified in its charter)

Delaware

56-2020050

(State or other jurisdiction of


incorporation or organization)

​

​

56-2020050
(I.R.S. Employer


Identification No.)

Number)

611 Gateway Blvd.

Catalyst Biosciences, Inc.
12730 High Bluff Drive
Suite 710

South 250

San Francisco, California 94080

Diego, CA 92130

(650)871-0761

266-8674

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Nassim Usman, Ph.D.


President and Chief Executive Officer

Catalyst Biosciences, Inc.

611 Gateway Blvd.

12730 High Bluff Drive
Suite 710

South 250

San Francisco, California 94080

Diego, CA 92130

(650)871-0761

266-8674

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copy

Copies to:

Stephen B. Thau

Morrison & Foerster LLP

755 Page Mill Road

Palo Alto, CA 94304

(650)813-5600

Stephen Thau
David Schwartz
Orrick, Herrington & Sutcliffe LLP
51 West 52nd Street
New York, NY 10019
(212) 506-5000
​​
Ryan A. Murr
Branden C. Berns
Gibson, Dunn & Crutcher LLP
555 Mission Street, Suite 3000
San Francisco, CA 94105
(415) 393-8200
Approximate date of commencement of proposed sale to the public:
From time to time or at one time as determined by the registrant after the effective date of this registration statement.

Registration Statement becomes effective.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box:box.  ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box:box. ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-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 Rule12b-2 of the Exchange Act.

Large accelerated filer  ☐
​☐​
Accelerated filer  ☐
​​
Non-accelerated filer ☒
​​
Emerging growth company  ☐
Non-accelerated filer
​☐​
​​
​​
Smaller reporting company
☒
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 7(a)(2)(B) of the Securities Act.  ☐

CALCULATION OF REGISTRATION FEE

 

Title of Each Class of

Securities to be Registered(1)

 

Amount

to be

Registered(1)(2)(3)

 

Proposed

Maximum

Offering Price

Per Unit(1)

 

Proposed

Maximum

Aggregate

Offering Price(1)(2)(3)

 

Amount of

Registration Fee(4)

Common Stock, par value $0.001 per share

        

Preferred Stock, par value $0.001 per share

        

Debt Securities

        

Warrants

        

Units

        

Total

     $200,000,000 $24,240

 

 

(1)

Not specified as to each class of securities to be registered pursuant to General Instruction II.D ofForm��S-3 under the Securities Act of 1933, as amended, or the Securities Act.

(2)

The registrant is hereby registering an indeterminate amount and number of each identified class of the identified securities up to a proposed maximum aggregate offering price of $200,000,000, which may be offered from time to time at indeterminate prices, including securities that may be purchased by underwriters. The registrant has estimated the proposed maximum aggregate offering price solely for the purpose of calculating the registration fee pursuant to Rule 457(o) under the Securities Act. Securities registered hereunder may be sold separately, together or as units with other securities registered hereunder.

(3)

The registrant is hereby registering an indeterminate amount and number of each identified class of the identified securities as may be issued upon conversion, exchange, exercise or settlement of any other securities that provide for such conversion, exchange, exercise or settlement. In addition, pursuant to Rule 416 under the Securities Act, the securities being registered hereunder include such indeterminate number of shares of common stock and preferred stock as may be issuable with respect to the shares being registered hereunder as a result of stock splits, stock dividends or similar transactions.

(4)

Calculated pursuant to Rule 457(o) under the Securities Act.

The registrant hereby amends this Registration Statementregistration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment whichthat specifically states that this Registration Statementregistration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until this Registration Statementregistration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

TABLE OF CONTENTS

The information in this preliminary prospectus is not complete and may be changed. WeThe Selling Stockholders may not sell these securities until the registration statement filed with the U.S. Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and we areis not soliciting offersan offer to buy these securities in any state or other jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED DECEMBER 21, 2018

PROSPECTUS

$200,000,000

LOGO

Common Stock

Preferred Stock

Debt Securities

Warrants

Units

FromOctober 24, 2023

Prospectus


1,240,442,745 Shares
COMMON STOCK
Offered by the Selling Stockholders
This prospectus relates to the potential resale from time to time we may offer and sell, in one or more offerings, in amounts, at prices and on terms determined atby the time of any such offering, common stock, preferred stock, debt securities, warrants, either individually or in units, with a total valueSelling Stockholders (as defined below) of up to $200,000,000. We1,240,442,745 shares of common stock, par value $0.001 per share (“Common Stock”), of Catalyst Biosciences, Inc. (the “Company”), including 123,400,000 shares of Common Stock issuable upon the conversion of the Company’s Series X Convertible Preferred Stock, par value $0.001 per share (“Convertible Preferred Stock”). The “Selling Stockholders” refer to ourGNI USA (as defined below), the Minority Holders (as defined below) and their respective permitted transferees. The shares of Common Stock registered by this prospectus are referred to herein as the “Resale Shares.” The Resale Shares consist of:
(i)
6,266,521 shares of Common Stock beneficially owned by GNI USA, Inc., a Delaware corporation (“GNI USA”), previously issued to GNI Group Ltd, a company incorporated under the laws of Japan with limited liability (“GNI Japan”), and GNI Hong Kong Limited, a company incorporated under the laws of Hong Kong with limited liability (“GNI Hong Kong Limited”), in a private issuance pursuant to the Asset Purchase Agreement, dated December 26, 2022 (the “F351 Agreement”), and ultimately transferred to GNI USA prior to the closing of the Transactions (as defined below);
(ii)
123,400,000 shares of Common Stock issuable upon conversion of 12,340 shares of Convertible Preferred Stock beneficially owned by GNI USA, previously issued to GNI Japan and GNI Hong Kong Limited in the private issuance pursuant to the F351 Agreement, and ultimately transferred to GNI USA prior to the closing of the Transactions;
(iii)
953,821,796 shares of Common Stock issuable to GNI USA pursuant to the Business Combination Agreement, dated December 26, 2022 (the “Business Combination Agreement”), by and among the Company, GNI USA, the individuals listed on Annex A thereto (the “Minority Holders”) and other parties thereto; and
(iv)
156,954,428 shares of Common Stock to be issued to the Minority Holders pursuant to the Business Combination Agreement.
Certain Resale Shares will be issued upon the completion of certain transactions contemplated by the Business Combination Agreement (the “Transactions”), subject to stockholder approval, which was obtained at the special meeting of stockholders of the Company held on August 29, 2023 (the “Special Meeting”).
Completion of the Transactions is subject to receipt of required regulatory approvals, including approval from the China Securities Regulatory Commission (“CSRC”) pursuant to the Trial Administrative Measures of Overseas Securities Offering and Listing by Domestic Enterprises (the “Trial Measures”), No. 1 to No. 5 Supporting Guidance Rules, the Notes on the Trial Measures, the Notice on Administration Arrangements for the Filing of Overseas Listings by Domestic Enterprises and the relevant CSRC Answers to Reporter Questions on the official website of CSRC. These regulations established a filing-based regime to regulate overseas offerings and listings by PRC domestic companies. On October 20, 2023, Beijing Continent Pharmaceuticals Co., Ltd (“BC”), a company organized under the laws of the People’s Republic of China (the “PRC”), of which the combined company will hold an indirect controlling interest following the consummation of the Transaction, received such approval from the CSRC in connection with the Transactions. The Company anticipates that the Transactions will be completed prior to the Outside Date (as defined in the Business Combination Agreement).
Further, at the Special Meeting, stockholders of the Company adopted and approved an amendment to the restated certificate of incorporation of the Company to effect a reverse stock split of Common Stock, by a ratio of not less than 1-for-10 and not more than 1-for-60. If all other conditions precedent to the completion of the Transactions are met or waived, we will file a prospectus supplement or an amendment to the registration statement of which this prospectus is a part, as applicable, to decrease the number of the Resale Shares by giving effect to the reverse stock split.
We are not offering or selling any shares of Common Stock under this prospectus, and we will not receive any proceeds from the sale of the Resale Shares by the Selling Stockholders pursuant to this prospectus. Our registration of the securities covered by this prospectus does not mean that the Selling Stockholders will offer or sell any of the Resale Shares. The Selling Stockholders may sell the Resale Shares covered by this prospectus in a number of different ways and at varying prices. We provide more information about how the Selling Stockholders may sell the Resale Shares in the section entitled “Plan of Distribution.”
If any underwriters, dealers or agents are involved in the sale of any of the Resale Shares, their names and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in an applicable prospectus supplement. See the sections of this prospectus entitled “About this Prospectus” and “Plan of Distribution” for more information.
Pursuant to the Business Combination Agreement, the “combined company” following the consummation of the Transactions will acquire an indirect controlling interest in BC. BC faces various risks and uncertainties related to doing business in the PRC. BC’s business operations are primarily conducted in the PRC, and BC is subject to complex and evolving PRC laws and regulations. For a detailed description of risks related to doing business in the PRC, please refer to the risks disclosed under “ Risk Factors—Risks Related to BC—Risks Related to BC’s Business Operations in the PRC ” in the Company’s Definitive Proxy Statement on Schedule 14A filed with the U.S. Securities and Exchange Commission (the “SEC”) on July 20, 2023 (the “Proxy Statement”).
The PRC government’s significant authority in regulating the combined company’s operations and its oversight and control over offerings conducted overseas by, and foreign investment in, PRC-based issuers could significantly limit or completely hinder the combined company’s ability to offer or continue to offer securities to investors and cause the value of the combined company’s securities to significantly decline or be worthless if the Transactions are consummated. Implementation of industry-wide regulations, including data security or anti-monopoly related regulations, in this nature could result in a material change in the combined company’s operations and may cause the value of the combined company’s securities to significantly decline or become worthless if the Transactions are consummated. Risks and uncertainties arising from the legal system in the PRC, including risks and uncertainties regarding the enforcement of laws and quickly evolving rules and regulations in the PRC could result in a material adverse change in the combined company’s operations and the value of the combined company’s common stock preferredif the Transactions are consummated. For example, in recent years, the PRC government has made statements and taken regulatory actions to regulate certain market players or to improve its supervision of the market in general, such as those related to data security or anti-monopoly concerns. There is no assurance that any new rules or regulations promulgated in the future will not impose additional requirements on the combined company. If any such rules or regulations are adopted, the combined company may be subject to more stringent regulatory scrutiny of its operation and financing efforts, which may in turn result in more compliance costs and expenses for the combined company, delay the combined company’s investment and financing activities, or otherwise impact the combined company’s ability to conduct its business, accept foreign investments, or list on a U.S. or other foreign exchange following the Transactions. For more details, see “Risk Factors Risks Related to BC—Risks Related to BC’s Business Operations in the PRC—The PRC government may intervene in or influence BC’s operations at any time, which could result in a change in BC’s operations” and “—There are uncertainties regarding the interpretation and enforcement of PRC laws, rules and regulations” in the Proxy Statement.
Continued on next page

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Pursuant to the Cybersecurity Review Measures published by the Cybersecurity Administration of the PRC, which became effective on February 15, 2022, critical information infrastructure operators purchasing network products and services which affect or may affect national security, or online platform operators possessing personal information of more than one million users, seeking to be listed on foreign stock debtmarkets must apply for a cybersecurity review by the Cybersecurity Review Office. For a detailed description, please refer to risks disclosed under “Risk Factors—Risks Related to BC—Risks Related to BC’s Business Operations in the PRC—Compliance with the PRC’s new Data Security Law, Cyber Security Law, Cybersecurity Review Measures, Personal Information Protection Law, regulations and guidelines relating to the multi-level protection scheme on cyber security and any other future laws and regulations may entail significant expenses and could affect BC’s business” in the Proxy Statement.
According to Special Administrative Measure (Negative List) for Access of Foreign Investments (2021 Edition) which became effective on January 1, 2022 (the “Negative List”), if a PRC company, which engages in any business where foreign investment is prohibited under the Negative List or prohibited businesses, seeks an overseas offering or listing, it must obtain approval from competent governmental authorities. For a detailed description, please refer to “BC’s Business—Regulations on M&A and Overseas Listings” in the Proxy Statement.
However, applicable PRC laws and regulations may be tightened, and new laws or regulations may be introduced to impose additional government approval, license, and permit requirements. If BC or its subsidiaries fail to obtain and maintain such approvals, licenses, or permits required for its business, inadvertently conclude that such approval is not required, or respond to changes in the regulatory environment, BC or its subsidiaries could be subject to liabilities, penalties, and operational disruption, which may materially and adversely affect its business, operating results, financial condition and the value of our ordinary shares, significantly limit or completely hinder the combined company’s ability to offer or continue to offer securities warrantsto investors, or cause such securities to significantly decline in value or become worthless.
Generally, cash is transferred through BC’s organization in the following manner: (i) funds are transferred to BC from Continent Pharmaceuticals Inc., a Cayman Islands company limited by shares (“CPI”) as needed through BJContinent Pharmaceuticals Limited, a company incorporated under the laws of Hong Kong with limited liability (“BJC Limited”), or from other domestic shareholders, in the form of capital contributions or shareholder loans; and units(ii) dividends or other distributions may be paid by BC to CPI through BJC Limited, or to other domestic shareholders.
In September 2020, BC paid a cash dividend of $1.9 million to BJC Limited. As required under the PRC Enterprise Income Tax Law, the dividends paid by BC were subject to a withholding tax rate of 10%. Such amount was settled in full net of withholding PRC tax through multiple payments by August 2020.
Since BC’s inception to the date of this prospectus, there were no transfers, dividends, or distributions between BJC Limited, BC, BC’s wholly-owned subsidiary (Beijing Continent Biomedical Technology Co., Ltd., a company organized under the laws of the PRC (“BC Biomedical”)), or to investors (except as “securities.disclosed above and excluding shareholder capital contributions). BC intends to retain all available funds and any future earnings for use in the operation of its business and does not anticipate paying any cash dividends on its capital stock in the foreseeable future. Notwithstanding the foregoing, any determination to pay cash dividends subsequent to the Transactions will be at the discretion of the combined company’s board of directors and will depend upon a number of factors, including the combined company’s results of operations, financial condition, future prospects, contractual restrictions, restrictions imposed by applicable law and other factors the combined company’s board of directors deems relevant. For more details, see “BC’s Business—Regulatory Requirements in the PRC—Dividends, Distributions and Other Transfers”

Our, Audited Financial Statements of Beijing Continent Pharmaceuticals Co., Ltd. and “Selected Historical and Unaudited Pro Forma Condensed Combined Financial Information—Unaudited Pro Forma Condensed Combined Financial Information” included in the Proxy Statement.

Under the Holding Foreign Companies Accountable Act (the “HFCAA”), the SEC is required to identify issuers that retain an auditor that has a branch or office that is located in a foreign jurisdiction and that the Public Company Accounting Oversight Board (the “PCAOB”) determines it is unable to inspect or investigate completely because of a position taken by an authority in that foreign jurisdiction. On December 16, 2021, the PCAOB issued a report on its determination that it is unable to inspect or investigate completely PCAOB-registered accounting firms headquartered in the PRC and in Hong Kong. On December 15, 2022, the PCAOB announced that it was able to conduct inspections and investigations of PCAOB-registered public accounting firms headquartered in mainland PRC and Hong Kong in 2022, and as a result, the PCAOB vacated its December 2021 determinations. While vacating those determinations, the PCAOB noted that, should it encounter any impediment to conducting an inspection or investigation of auditors in mainland PRC or Hong Kong as a result of a position taken by any authority there, the PCAOB would act to immediately reconsider the need to issue new determinations consistent with the HFCAA and PCAOB Rule 6100.
If (i) the combined company’s operations require that it retain an auditor that is headquartered in mainland PRC to act as a principal auditor in order to comply with the standards of the PCAOB and (ii) the PCAOB retakes a position that is similar to its December 2021 determinations, then the combined company would be identified by the SEC as a Commission-Identified Issuer. In accordance with the HFCAA, the combined company’s securities would be prohibited from being traded on a national securities exchange or in the over-the-counter trading market in the United States if the SEC identifies the combined company as a Commission-Identified Issuer for two consecutive years in the future. The combined company’s operations will likely require such an auditor to act as its principal auditor. For a detailed description of risks of and impacts on the combined company relating to the HFCAA and related regulations, please refer to risks disclosed under “Risk Factors—Risks Related to the Combined Company—The PRC-operations portion of the combined company’s audit may be conducted by an independent registered public accounting firm that is not subject to inspection by the PCAOB, which may negatively impact investor sentiment towards the combined company or its PRC operations, which could adversely affect the market price of the combined company’s common stock trades” in the Proxy Statement.
Our Common Stock is currently listed on The Nasdaq Capital Market (“Nasdaq”) under the symbol “CBIO.” We have applied to continue the listing of our Common Stock on Nasdaq under the symbol “GYRE” upon the completion of the Transactions. It is a condition to the completion of the Transactions that the Resale Shares be approved for listing on Nasdaq (subject only to official notice of issuance thereof), but there can be no assurance that such listing condition will be met. If such listing condition is not met, the Transactions will not be consummated unless the listing condition is waived pursuant to the terms of the Business Combination Agreement.
On December 20, 2018,October 23, 2023, the last reported sale price of the common stockour Common Stock as reported on The Nasdaq Capital Market was $7.10$0.466 per share.

This

Investing in our Common Stock involves risk. See “Risk Factors” beginning on page 11 of this prospectus provides you withand in the documents incorporated by reference in this prospectus for a general descriptiondiscussion of the securities we may offer. Each time we offer securities using this prospectus, we will provide the specific terms of the securities and the offering in one or more supplementsfactors you should carefully consider before deciding to this prospectus. We may also authorize one or more free writing prospectuses to be provided to you in connection withpurchase these offerings. securities.
The prospectus supplement and any related free writing prospectus will also describe the specific manner in which we will offer the securities and may also supplement, update or amend information contained in this prospectus. You should read this prospectus, any accompanying prospectus supplement and any related free writing prospectus carefully before you purchase any of our securities.

We may offer the securities in amounts, at prices and on terms determined at the time of offering. We may sell the securities directly to you, through agents designated from time to time or to or through underwriters or dealers, on a continuous or delayed basis. If we use agents, underwriters or dealers to sell the securities, we will name them and describe their compensation in a prospectus supplement. You can find additional information about our plan of distribution for the securities under the heading “Plan of Distribution” in this prospectus. We will also describe the plan of distribution for any particular offering of these securities in the prospectus supplement. This prospectus may not be used to offer and sell securities unless accompanied by a prospectus supplement.

INVESTING IN OUR SECURITIES INVOLVES A HIGH DEGREE OF RISK. YOU SHOULD CAREFULLY READ AND CONSIDER THE RISKS AND UNCERTAINTIES DESCRIBED IN THIS PROSPECTUS, ANY ACCOMPANYING PROSPECTUS SUPPLEMENT AND ANY RELATED FREE WRITING PROSPECTUS AND IN THE DOCUMENTS INCORPORATED BY REFERENCE INTO THIS PROSPECTUS, ANY ACCOMPANYING PROSPECTUS SUPPLEMENT AND ANY RELATED FREE WRITING PROSPECTUS. SEE “RISK FACTORS” BEGINNING ON PAGE 5.

Neither the Securities and Exchange Commission nor anyand state securities commission hasregulators have not approved or disapproved of these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is      , 2018

2023.

TABLE OF CONTENTS

TABLE OF CONTENTS
​​
Page

Caption

About this Prospectus
​Page​
1

ABOUT THIS PROSPECTUSCautionary Note Regarding Forward-Looking Statements

​​1
2

OUR COMPANYWhere You Can Find More Information

​​2
4

CAUTIONARY NOTE REGARDING FORWARD-LOOKING INFORMATIONInformation Incorporated by Reference

​​3
5

RISK FACTORSProspectus Summary

​​5
6

USE OF PROCEEDSThe Offering

​​5
10

DESCRIPTION OF CAPITAL STOCKRisk Factors

​​6
11

ADDITIONAL INFORMATION CONCERNING OUR CAPITAL STOCKUse of Proceeds

​​11
12

DESCRIPTION OF DEBT SECURITIESSelling Stockholders

​​14
13

DESCRIPTION OF WARRANTSPlan of Distribution

​​21
15

DESCRIPTION OF UNITSDividend Policy

​​23
17

PLAN OF DISTRIBUTIONLegal Matters

​​25
18

LEGAL MATTERSExperts

​​27
19

EXPERTSPart II Information Not Required In Prospectus

​​27
II-1

WHERE YOU CAN FIND MORE INFORMATIONSignatures

​​28
II-6
i

You should rely only on the information contained or incorporated by reference in this prospectus, in any accompanying prospectus supplement or in any related free writing prospectus filed by us with the U.S. Securities and Exchange Commission (the “SEC”). We have not authorized any other person to provide you with different information. If anyone provides you with additional, different or inconsistent information, you should not rely on it. You should not assume that the information appearing in this prospectus, any applicable prospectus supplement, any related free writing prospectus or any documents incorporated by reference herein or therein is accurate as of any date other than the dates of those documents. Our business, financial condition, results of operations and prospects may have changed since those dates. Any information contained on or accessible through our Internet site is not incorporated herein and does not constitute part of this prospectus.TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

This prospectus is part of athe registration statement on FormS-3 that we filed with the U.S. Securities and Exchange Commission, or the SEC using a “shelf” registration process. Under this shelf registration process, wethe Selling Stockholders may, from time to time, issue,sell the shares of our Common Stock through any means described in the section entitled “Plan of Distribution.” More specific terms of any securities that the Selling Stockholders offer and sell to the public any part of the securities describedmay be provided in this prospectus, together or separately, in one or more offerings, for a maximum aggregate offering price not to exceed $200,000,000.

This prospectus provides you with a general description of the securities we may offer. Each time we sell any securities under this prospectus, we will provide a prospectus supplement containing morethat describes, among other things, the specific information aboutamounts and prices of the Common Stock being offered and the terms of that offering, including the specific amounts, prices and terms of the securities offered. Any such prospectus supplement may include a discussion of risks or other special considerations applicable to us or the securities offered thereby. Any suchoffering.

A prospectus supplement may also add, update or change information included in this prospectus. Any statement contained in this prospectus will be deemed to be modified or in documents incorporated by reference insuperseded for purposes of this prospectus. Toprospectus to the extent that a statement contained in such prospectus supplement modifies or supersedes such statement. Any statement so modified will be deemed to constitute a part of this prospectus only as so modified, and any statement thatso superseded will be deemed not to constitute a part of this prospectus.
Neither we make in a prospectus supplement is inconsistentnor the Selling Stockholders have authorized anyone to provide you with statements made in this prospectus or in documents incorporated by reference in this prospectus,any information other than the statements madeinformation contained or incorporated by reference in this prospectus will be deemed modified or superseded by those made in the prospectus supplement.

This prospectus and any applicable prospectus supplement contain and incorporate by reference market data, industry statistics and other data that have been obtained or compiled from information made available by third parties. These data, to the extent they contain estimates or projections, involve a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates or projections. Industry publications and other reports we have obtained from independent parties generally state that the data contained in these publications or other reports have been obtained in good faith or from sources considered to be reliable, but they do not guarantee the accuracy or completeness of such data. We urge you to carefully read this prospectus, any applicable prospectus supplement and any related free writing prospectus prepared by or on behalf of us in connection with this offering to which we have referred you. We and the Selling Stockholders take no responsibility for, and can provide no assurances as to the reliability of, any documentsother information that we incorporateothers may give you. The information contained or incorporated by reference in this prospectus or any applicable prospectus supplement and any relatedsuch free writing prospectus provided in connection with this offering is accurate only as of the date thereof, regardless of the time of delivery of such document or of any sale of our Common Stock. Our business, financial condition and results of operations may have changed since those dates. It is important for you to read and consider all the information contained in this prospectus, including the documents incorporated by reference herein or any free writing prospectus prepared by or on behalf of us in connection with this offering, in making your investment decision.

The Selling Stockholders are not offering to sell, or seeking offers to buy, shares of our Common Stock in any jurisdictions where offers and sales are not permitted. The distribution of this prospectus and the additional informationoffering of the Resale Shares in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the Resale Shares and the distribution of this prospectus outside the United States. This prospectus does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.
This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is made to the actual documents for complete information. All of the summaries are qualified in their entirety by the actual documents. Copies of some of the documents referred to herein have been filed, will be filed or will be incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below under “Where“Where You Can Find More Information” before making an investment decision.

This document may only be used where it is legal to sell these securities. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any jurisdiction whether the offer or sale is not permitted.

THIS PROSPECTUS MAY NOT BE USED TO OFFER AND SELL SECURITIES UNLESS IT IS ACCOMPANIED BY A PROSPECTUS SUPPLEMENT.

For purposes ofInformation.”

In this prospectus, references tounless otherwise indicated or the context otherwise requires, the terms “Catalyst,” the “Company,” “we,” “us” and “our” refer to Catalyst Biosciences, Inc., a Delaware corporation, unless the context otherwise requires.

The registration statement containing this prospectus, including exhibits to the registration statement, provides additional information about us and the securities offered under this prospectus. The registration statement can be read at the SEC’s website or at the SEC offices mentioned under the heading “Where You Can Find More Information.”

1
OUR COMPANY

TABLE OF CONTENTS

We are a clinical-stage biopharmaceutical company focused on developing novel medicines to address serious medical conditions for individuals who need new or better treatment options. We are focusing our product development efforts in the field of hemostasis (the process that regulates bleeding) and have a mission to develop valuable therapies for individuals with hemophilia. We used a scientific approach to engineer several protease-based therapeutic candidates that regulate blood clotting.

Additional details of our development or clinical programs and related strategic agreements are contained in our Annual Report on Form10-K for the fiscal year ended December 31, 2017 and our Quarterly Reports on Form10-Q for the quarterly periods ended March 31, 2018, June 30, 2018 and September 30, 2018.

We commenced operations in 2002 and are a Delaware corporation. Our corporate headquarters are located at South San Francisco, California 94080. Our telephone number is (650)871-0761, and our website address is www.catalystbiosciences.com. The information on or accessible through our website does not constitute part of this prospectus or any accompanying prospectus supplement and should not be relied upon in connection with making any investment in our securities. Further, our reference to the URL for the website is intended to be an inactive textual reference only. We make our annual reports on Form10-K, quarterly reports on Form10-Q, current reports on Form8-K, and amendments to these reports available free of charge on our website as soon as reasonably practicable after we file these reports with the SEC. Our Code of Ethics can be found on our website.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING INFORMATION

STATEMENTS

This prospectus and any accompanying prospectus supplement, as well as the documents we incorporateincorporated by reference herein or therein, containscontain forward-looking statements within the meaning of Section 27Athe Private Securities Litigation Reform Act of 1995. Forward-looking statements include information concerning our future results of operations and financial position, strategy and plans, and our expectations for future operations. Forward-looking statements include all statements that are not historical facts and, in some cases, can be identified by terms such as “anticipate,” “believe,” “continue,” “could,” “design,” “estimate,” “expect,” “intend,” “may,” “plan,” “possible,” “potential,” “predict,” “project,” “seek,” “should,” “target,” “will,” “would” or the negative version of these words and similar expressions.
Forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements, including those described in “Risk Factors” included elsewhere in this prospectus and in the documents that are incorporated by reference herein. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Also, forward-looking statements represent our beliefs and assumptions only as of the Securities Actdate of this prospectus, or, in the case of any document incorporated by reference herein in this prospectus, as of the date of such document. In light of the significant uncertainties in these forward-looking statements, you should not regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and Section 21Eplans in any specified time frame, or at all. You should read this prospectus and the documents incorporated by reference herein completely and with the understanding that our actual future results may be materially different from what we expect.
These forward-looking statements include, but are not limited to, statements concerning the following:
the ability of our clinical trials to demonstrate safety and efficacy of our product candidates and other positive results;
our ability to develop a pipeline of product candidates to address unmet needs in the treatment of organ fibrosis and other inflammatory diseases;
the timing, progress and results of clinical trials for Hydronidone from the Company’s Phase 2a trial and other product candidates that the Company may develop, including statements regarding the timing of initiation and completion of studies or trials and related preparatory work, the period during which the results of the studies or trials will become available and research and development programs;
the timing, scope and likelihood of regulatory filings and approvals, including timing of investigational new drug applications and final approval of Hydronidone from the U.S. Food and Drug Administration for the treatment of nonalcoholic steatohepatitis (“NASH”) and liver fibrosis associated with chronic hepatitis B, and any other future product candidates;
the timing, scope or likelihood of foreign regulatory filings and approvals;
our expectations regarding the reconsideration of its strategic alternatives in the event the Transactions are not completed;
our expectations regarding the future pursuit of product development efforts, including whether it will pursue such efforts, estimates regarding the expenses, future revenue, timing of any future revenue, capital requirements and need for additional financing related to such efforts, the timing of and ability of the Company to pursue such efforts and the Company’s plans to develop and, if approved, subsequently commercialize any product candidates resulting from such efforts;
our expectations regarding its ability to fund its operating expenses and capital expenditure requirements with its cash, cash equivalents and investments;
our ability to develop and advance current product candidates and programs into, and successfully complete, clinical studies;
our manufacturing, commercialization and marketing capabilities and strategy;
plans relating to commercializing our product candidates, if approved, including the geographic areas of focus and sales strategy;
the need to hire additional personnel and our ability to attract and retain such personnel;
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the size of the market opportunity for our product candidates, including estimates of the number of patients who suffer from the diseases the Company is targeting;
expectations regarding the approval and use of our product candidates in combination with other drugs;
expectations regarding potential for accelerated approval or other expedited regulatory designation;
our competitive position and the success of competing therapies that are or may become available;
estimates of the number of patients that the Company will enroll in its clinical trials;
the beneficial characteristics and the potential safety, efficacy and therapeutic effects of our product candidates;
our ability to obtain and maintain regulatory approval of its product candidates and its expectations regarding particular lines of therapy;
plans relating to the further development of our product candidates, including additional indications the Company may pursue;
existing regulations and regulatory developments in the United States, Europe, and other jurisdictions;
expectations regarding the impact of the COVID-19 pandemic on our business;
our intellectual property position, including the scope of protection the Company is able to establish and maintain for intellectual property rights covering Hydronidone, and other product candidates it may develop, including the extensions of existing patent terms where available, the validity of intellectual property rights held by third parties and our ability not to infringe, misappropriate or otherwise violate any third-party intellectual property rights;
our continued reliance on third parties to conduct additional clinical trials of our product candidates and for the manufacture of its product candidates for clinical trials;
our relationships with patient advocacy groups, key opinion leaders, regulators, the research community and payors;
our ability to obtain and negotiate favorable terms of, any collaboration, licensing or other arrangements that may be necessary or desirable to develop, manufacture or commercialize our product candidates;
the pricing and reimbursement of Hydronidone, and other product candidates the Company may develop, if approved;
the rate and degree of market acceptance and clinical utility of Hydronidone, and other product candidates the Company may develop;
our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;
our financial performance;
the period over which the Company estimates its existing cash and cash equivalents will be sufficient to fund its planned operating expenses and capital expenditure requirements;
statements regarding the approval and closing of the Transactions;
the timing of the consummation of the Transactions;
our ability to solicit a sufficient number of proxies to approve the change of control resulting from the Transactions;
satisfaction of conditions to the completion of the Transactions;
the expected benefits of the Transactions;
our ability to complete the Transactions;
expectations about the continued listing of Common Stock on Nasdaq;
the impact of laws and regulations; and
expectations regarding the period during which the Company will qualify as a smaller reporting company under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). All statements, other than statements
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WHERE YOU CAN FIND MORE INFORMATION
We have filed with the SEC this registration statement under the Securities Act of historical facts, included or incorporated in1933, as amended (the “Securities Act”) covering the Common Stock to be offered and sold by this prospectus regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects, plans, intentions and objectivesany applicable prospectus supplement. This prospectus does not contain all of management are forward-looking statements. We may,the information included in the registration statement, some cases, use words such as “believe,” “anticipate,” “should,” “could,” “intend,” “plan,” “may,” “will,” “seek,” “estimate,” “predict,” “project,” “potentially,” “continue,” “expect” orof which is contained in exhibits to the negative of these terms or similar expressions, although not all forward-looking statements contain these identifying words. These statements are based on our management’s assumptions and assessments in light of information currently available to our management, its experience and its perception of historical trends, current conditions, expected future developments and other factors our management believes to be appropriate. These forward-looking statementsregistration statement. In addition, we are subject to a numberthe information and periodic and current reporting requirements of risks and uncertainties, including those risks described under “Risk Factors”the Exchange Act, and in accordance therewith, we file periodic and current reports, proxy statements and other sections ininformation with the SEC.
You may access our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, proxy statements on Schedule 14A and amendments or supplements to those reports and statements, filed with the SEC, free of charge at our website at www.catalystbiosciences.com or by means of the SEC’s website at www.sec.gov. The information found on, or that can be accessed from or that is hyperlinked to, our website or the SEC’s website is not part of this prospectus and in our current and periodic reports, and other filings, filed from timeyou should not rely on that information when making a decision to time with the SEC that are incorporated by reference into this prospectus, that could cause actual results to differ materially from those anticipated in the forward-looking statements. See “Where You Can Find More Information” below and for information about how to obtain copies of those documents.

Forward-looking statements included or incorporated by reference in this prospectus include, for example, statements about:

the strategies, prospects, plans, expectations or objectives of management for future operations;

our focus on specific product candidates;

the progress, scope or duration of the development of product candidates or programs, clinical trial plans, timelines and potential results;

the benefits that may be derived from product candidates or the commercial or market opportunity in any target indication;

our ability to protect intellectual property rights;

our anticipated operations, financial position, revenues, costs or expenses, statements regarding future economic conditions or performance, statements of belief and any statement of assumptions underlying any of the foregoing;

potential regulatory filings for or approval of any of our product candidates;

the progress of our third-party collaborations, including estimated milestones;

our intention to seek, and the ability to enter into, strategic alliances and collaborations;

the responsibilities of our collaborators, including the responsibility to make cost reimbursement, milestone, royalty and other payments to us, and our expectations regarding our collaborators’ plans with respect to our products;

our responsibilities to our collaborators, including our responsibilities to conduct research and development, clinical trials and manufacture products;

the results and timing of clinical trials and the possible commencement of future clinical trials;

conditions for obtaining regulatory approval of our product candidates;

submission and timing of applications for regulatory approval;

the impact of the U.S. Food and Drug Administration (FDA) and other government regulations on our business;

uncertainties associated with obtaining and protecting patents and other intellectual property rights, as well as avoiding the intellectual property rights of others;

products and companies that will compete with the products we license to third-party collaborators;

the possibility we may commercialize our own products and build up our commercial, sales and marketing capabilities and other required infrastructure;

our employees, including the number of employees and the continued service of key management, technical and scientific personnel;

our future performance and obligations under agreements we have entered into, such as the definitive agreement related to the termination of the Pfizer Agreement;

our future performance and our expectations regarding our ability to achieve profitability;

requirements for us to purchase supplies and raw materials from third parties, and the ability of third parties to provide us with required supplies and raw materials;

sufficiency of our cash resources, anticipated capital requirements and capital expenditures and our need for additional financing;

the composition of future revenues;

accounting policies and estimates, including revenue recognition policies; and

statements of belief and any statement of assumptions underlying any of the foregoing.

Any such forward-looking statements are not guarantees of future performance and are subject to certain risks and uncertainties that could cause actual results to differ materially from those contemplated by such forward-looking statements. All such forward-looking statements are made only as of the date of the document in which they are contained, based on our management’s beliefs and assumptions and information available to us as of the date of that document, and we caution you not to place undue reliance on forward-looking statements in light of the risks and uncertainties associated with them. We undertake no obligation, and disclaim any duty, to update or revise any forward-looking statements in light of future developments. You should also carefully consider other information set forth in reports or other documents that we file with the SEC.

RISK FACTORS

Our business is subject to certain risks and uncertainties. Before you invest in our securities, in addition to the other information, documents or reports incorporated by referenceCommon Stock.

Any statement made in this prospectus and any prospectus supplement, periodic and current reports, proxy statements and other information filed or furnished with the SEC concerning the contents of any contract, agreement or other document is only a summary of the actual contract, agreement or other document. If we have filed any contract, document, agreement or other document as an exhibit to such filing or furnishing, you should read the exhibit for a more complete understanding of the document or matter involved. Each statement regarding a contract, agreement or other document is qualified in its entirety by reference to the actual document.
Upon written or oral request, we will provide without charge to each person to whom a copy of the prospectus is delivered a copy of the documents incorporated by reference herein (other than exhibits to such documents unless such exhibits are specifically incorporated by reference herein). You may request a copy of these filings, at no cost, by writing or calling us at the contact information set forth below. We have authorized no one to provide you with any information that differs from that contained in this prospectus. Accordingly, we take no responsibility for any other information that others may give you. You should not assume that the information in this prospectus is accurate as of any date other than the date of the front cover of this prospectus.
Catalyst Biosciences, Inc.
Investor Relations
12730 High Bluff Drive,
Suite 250
San Diego, CA 92130
(650) 266-8674
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INFORMATION INCORPORATED BY REFERENCE
The SEC allows us to “incorporate by reference” the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference herein is considered to be part of this prospectus, and information that we file later with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below (except the information contained in such documents to the extent “furnished” and not “filed”) and any future filings we make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act (except the information contained in such documents to the extent “furnished” and not “filed”):
•
our Annual Report on Form 10-K for the fiscal year ended December 31, 2022 filed with the SEC on March 30, 2023 (and any portions of the Proxy Statement that are incorporated by reference into our Annual Report on Form 10-K for the year ended December 31, 2022);
•
our Quarterly Reports on Form 10-Q for the fiscal quarters ended March 31, 2023 and June 30, 2023 filed with the SEC on May 15, 2023 and August 14, 2023, respectively;
•
our Current Reports on Form 8-K as filed with the SEC on January 19, 2023, March 2, 2023, March 30, 2023, April 7, 2023, May 5, 2023, June 20, 2023, and August 31, 2023;
•
the Proxy Statement; and
•
the Description of Catalyst Capital Stock section contained in the Proxy Statement, including any amendment or report filed for the purpose of updating such description.
We will provide without charge upon written or oral request a copy of any or all of the documents that are incorporated by reference herein into this prospectus, other than exhibits which are specifically incorporated by reference herein into such documents. Requests should be directed to our Investor Relations department at Catalyst Biosciences, Inc., 12730 High Bluff Drive, Suite 250, San Diego, CA 92130. Our telephone number is (650) 266-8674.
Any statement contained in a document incorporated or deemed to be incorporated by reference herein into this prospectus shall be deemed to be modified or superseded for the purposes of this prospectus to the extent that a statement contained in this prospectus (or in any document incorporated by reference herein therein) or in any other subsequently filed document that is or is deemed to be incorporated by reference herein into this prospectus modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this prospectus.
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PROSPECTUS SUMMARY
You should read the following summary together with the entire prospectus and the documents incorporated by reference herein, including our consolidated financial statements and related notes as well as any free writing prospectus prepared by us or on our behalf. You should carefully consider, among other things, the matters discussed in the sections entitled “Risk Factors” included in or incorporated by reference in this prospectus.
Our Company
We are a biopharmaceutical company focused on the development and commercialization of Hydronidone for the treatment of NASH in the United States. Hydronidone is being evaluated for the treatment of liver fibrosis associated with a broad spectrum of chronic liver diseases. A Phase 1 clinical trial of Hydronidone has been completed in the United States and generated pharmacokinetics (“PK”), safety and tolerability data of single and multiple ascending doses of Hydronidone in U.S. healthy subjects.
We anticipate filing an investigational new drug application for the treatment of NASH in the United States in late 2023. NASH is a severe form of nonalcoholic fatty liver disease, characterized by inflammation and fibrosis in the liver that can progress to cirrhosis, liver failure, hepatocellular carcinoma and death. There are currently no approved products for the treatment of NASH.
We plan to initiate the clinical development of Hydronidone in NASH fibrosis in a randomized, double-blind, placebo-controlled, parallel group, Phase 2a, Proof-of-Concept (“PoC”) clinical study evaluating the safety, tolerability, PK, and Pharmacodynamics (“PD”) of Hydronidone capsules administered daily at an oral dose of 360 mg (given as 120 mg thrice daily) for 24 weeks to adult subjects with advanced liver fibrosis associated with noncirrhotic NASH. The main goal of the proposed Phase 2a study is to obtain early PoC for Hydronidone in subjects with NASH fibrosis as a basis of expansion into a more comprehensive Phase 2/3 clinical program, provided that the drug is successful. The study will include a small sample size (total of 60 evaluable subjects) who will receive in a 2:1 ratio Hydronidone or Placebo. The study will evaluate changes from baseline in a set of noninvasive biochemical and imaging biomarkers relevant to assessment of NASH fibrosis in the context of drug exposure, as well as the mechanism of anti-fibrotic action of Hydronidone. The study will employ PK blood sampling and assessment of the initial population PK and PK/PD relationship to inform Hydronidone treatment in future clinical studies in NASH fibrosis. In addition, this trial will include a disease-specific patient-reported outcomes, a validated composite Chronic Liver Disease Questionnaire – NASH, to collect patient-reported data about the impact of Hydronidone treatment on quality of life of subjects with advanced NASH fibrosis.
Prior to our acquisition from GNI Japan and GNI Hong Kong Limited, of all of the assets and intellectual property rights primarily related to the proprietary Hydronidone compound, other than such assets and intellectual property rights located in the PRC, we were engaged in the research and development of product candidates from our protease engineering platform. In February 2022, we engaged Perella Weinberg Partners as a financial advisor to assist our company in exploring strategic alternatives to monetize our assets. In March 2022, we ceased research and development activities and in May 2022, we entered into an asset purchase agreement with Vertex Pharmaceuticals Inc., pursuant to which Vertex Pharmaceuticals Inc. (“Vertex”) purchased our complement portfolio, including CB 2782-PEG and CB 4332, as well as our complement-related intellectual property, including the ProTUNE™ and ImmunoTUNE™ platforms, for $60.0 million in cash consideration (the “Vertex Transaction”). $55.0 million was received upfront in May 2022 and the remaining $5.0 million was received in May 2023 upon satisfaction of certain post-closing indemnification obligations. The hold-back amount was initially recorded within accounts and other receivables on the condensed consolidated balance sheet. In June 2023, we distributed $3.5 million, which reflected, in consideration with the Vertex Transaction, the hold-back amount received from Vertex less expenses and a reserve for potential tax liabilities to holders of the contingent value right issued to our stockholders of record on January 5, 2023 (the “CVR Holders”). On February 27, 2023, we signed an asset purchase agreement with GC Biopharma (“GCBP”) pursuant to which GCBP acquired our legacy rare bleeding disorders programs, including marzeptacog alpha activated, dalcinonacog alpha and CB-2679d-GT, for a total of $6 million; $1 million payable on signing and $5 million payable on February 28, 2025, subject to satisfaction of post-closing indemnification obligations. In March 2023, we distributed net proceeds of approximately $0.2 million to the CVR Holders. Once received, any additional net proceeds from the transaction will be distributed to the CVR Holders. We are also pursuing certain legal claims against a third party related to payments under a 2016 asset purchase agreement, and any net recoveries related to these claims will be distributed to the CVR Holders.
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We had a net loss of $8.2 million for the year ended December 31, 2022 and $2.2 million for the six months ended June 30, 2023, and an accumulated deficit of $410.9 million as of December 31, 2022 and $413.1 million as of June 30, 2023. As of December 31, 2022, we had $21.7 million of cash and cash equivalents. As of June 30, 2023, we had $6.9 million of cash and cash equivalents. Substantially all our operating losses were incurred in its research and development programs and in our general and administrative operations. For a description of our business, financial condition, results of operations and other important information regarding us and our business, we refer you to our filings with the SEC, incorporated by reference in this prospectus. For instructions on how to find copies of these documents, see “Where You Can Find More Information.”
Pursuant to the Business Combination Agreement, following the consummation of the Transactions, we (as the combined company following the consummation of the Transactions) will acquire an indirect controlling interest in BC. BC faces various risks and uncertainties related to doing business in the PRC. BC’s business operations are primarily conducted in the PRC, and BC is subject to complex and evolving PRC laws and regulations. For a detailed description of risks related to doing business in the PRC, please refer to the risks disclosed under “Risk Factors—Risks Related to BC—Risks Related to BC’s Business Operations in the PRC” in the Proxy Statement.
The PRC government’s significant authority in regulating the combined company’s operations and its oversight and control over offerings conducted overseas by, and foreign investment in, PRC-based issuers could significantly limit or completely hinder the combined company’s ability to offer or continue to offer securities to investors and cause the value of the combined company’s securities to significantly decline or be worthless if the Transactions are consummated. Implementation of industry-wide regulations, including data security or anti-monopoly related regulations, in this nature could result in a material change in the combined company’s operations and may cause the value of the combined company’s securities to significantly decline or become worthless if the Transactions are consummated. Risks and uncertainties arising from the legal system in the PRC, including risks and uncertainties regarding the enforcement of laws and quickly evolving rules and regulations in the PRC could result in a material adverse change in the combined company’s operations and the value of the combined company’s common stock if the Transactions are consummated. For example, in recent years, the PRC government has made statements and taken regulatory actions to regulate certain market players or to improve its supervision of the market in general, such as those related to data security or anti-monopoly concerns. There is no assurance that any new rules or regulations promulgated in the future will not impose additional requirements on the combined company. If any such rules or regulations are adopted, the combined company may be subject to more stringent regulatory scrutiny for its operation and financing efforts, which may in turn result in more compliance costs and expenses for the combined company, delay the combined company’s investment and financing activities, or otherwise impact the combined company’s ability to conduct its business, accept foreign investments, or list on a U.S. or other foreign exchange following the Transactions. For more details, see “Risk Factors Risks Related to BC—Risks Related to BC’s Business Operations in the PRC—The PRC government may intervene in or influence BC’s operations at any time, which could result in a change in BC’s operations and There are uncertainties regarding the interpretation and enforcement of PRC laws, rules and regulations” in the Proxy Statement.
Pursuant to the Cybersecurity Review Measures published by the Cybersecurity Administration of the PRC, which became effective on February 15, 2022, critical information infrastructure operators purchasing network products and services which affect or may affect national security, or online platform operators possessing personal information of more than one million users, seeking to be listed on foreign stock markets must apply for a cybersecurity review by the Cybersecurity Review Office. For a detailed description, please refer to risks disclosed under “Risk Factors—Risks Related to BC—Risks Related to BC’s Business Operations in the PRC—Compliance with the PRC’s new Data Security Law, Cyber Security Law, Cybersecurity Review Measures, Personal Information Protection Law, regulations and guidelines relating to the multi-level protection scheme on cyber security and any other future laws and regulations may entail significant expenses and could affect BC’s business” in the Proxy Statement.
According to the Negative List, if a PRC company, which engages in any business where foreign investment is prohibited under the Negative List, or prohibited businesses, seeks an overseas offering materials,or listing, it must obtain approval from competent governmental authorities. For a detailed description, please refer to “BC’s Business—Regulations on M&A and Overseas Listings” in the Proxy Statement.
However, applicable PRC laws and regulations may be tightened, and new laws or regulations may be introduced to impose additional government approval, license, and permit requirements. If BC or its subsidiaries fail to obtain and maintain such approvals, licenses, or permits required for its business, inadvertently conclude that such
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approval is not required, or respond to changes in the regulatory environment, BC or its subsidiaries could be subject to liabilities, penalties, and operational disruption, which may materially and adversely affect its business, operating results, financial condition and the value of our ordinary shares, significantly limit or completely hinder the combined company’s ability to offer or continue to offer securities to investors, or cause such securities to significantly decline in value or become worthless.
Generally, cash is transferred through BC’s organization in the following manner: (i) funds are transferred to BC from CPI as needed through BJC Limited, or from other domestic shareholders, in the form of capital contributions or shareholder loans; and (ii) dividends or other distributions may be paid by BC to CPI through BJC Limited, or to other domestic shareholders.
In September 2020, BC paid a cash dividend of $1.9 million to BJC Limited. As required under the PRC Enterprise Income Tax Law, the dividends paid by BC were subject to a withholding tax rate of 10%. Such amount was settled in full net of withholding PRC tax through multiple payments by August 2020.
Since BC’s inception to the date of this prospectus, there were no transfers, dividends, or distributions between BJC Limited, BC, BC’s wholly-owned subsidiary (BC Biomedical), or to investors (except as disclosed above and excluding shareholder capital contributions). BC intends to retain all available funds and any future earnings for use in the operation of its business and does not anticipate paying any cash dividends on its capital stock in the foreseeable future. Notwithstanding the foregoing, any determination to pay cash dividends subsequent to the Transactions will be at the discretion of the combined company’s board of directors and will depend upon a number of factors, including the combined company’s results of operations, financial condition, future prospects, contractual restrictions, restrictions imposed by applicable law and other factors the combined company’s board of directors deems relevant. For more details, see “BC’s Business—Regulatory Requirements in the PRC—Dividends, Distributions and Other Transfers”, Audited Financial Statements of Beijing Continent Pharmaceuticals Co., Ltd. and “Selected Historical and Unaudited Pro Forma Condensed Combined Financial Information—Unaudited Pro Forma Condensed Combined Financial Information” included in the Proxy Statement.
Under the HFCAA, the SEC is required to identify issuers that retain an auditor that has a branch or office that is located in a foreign jurisdiction and that the PCAOB determines it is unable to inspect or investigate completely because of a position taken by an authority in that foreign jurisdiction. On December 16, 2021, the PCAOB issued a report on its determination that it is unable to inspect or investigate completely PCAOB-registered accounting firms headquartered in the PRC and in Hong Kong. On December 15, 2022, the PCAOB announced that it was able to conduct inspections and investigations of PCAOB-registered public accounting firms headquartered in mainland PRC and Hong Kong in 2022, and as a result, the PCAOB vacated its December 2021 determinations. While vacating those determinations, the PCAOB noted that, should it encounter any impediment to conducting an inspection or investigation of auditors in mainland PRC or Hong Kong as a result of a position taken by any authority there, the PCAOB would act to immediately reconsider the need to issue new determinations consistent with the HFCAA and PCAOB Rule 6100.
If (i) the combined company’s operations require that it retain an auditor that is headquartered in mainland PRC to act as a principal auditor in order to comply with the standards of the PCAOB and (ii) the PCAOB retakes a position that is similar to its December 2021 determinations, then the combined company would be identified by the SEC as a Commission-Identified Issuer. In accordance with the HFCAA, the combined company’s securities would be prohibited from being traded on a national securities exchange or in the over-the-counter trading market in the United States if the SEC identifies the combined company as a Commission-Identified Issuer for two consecutive years in the future. The combined company’s operations will likely require such an auditor to act as its principal auditor. For a detailed description of risks of and impacts on the combined company relating to the HFCAA and related regulations, please refer to risks disclosed under “Risk Factors—Risks Related to the Combined Company—The PRC-operations portion of the combined company’s audit may be conducted by an independent registered public accounting firm that is not subject to inspection by the PCAOB, which may negatively impact investor sentiment towards the combined company or its PRC operations, which could adversely affect the market price of the combined company’s common stock.” in the Proxy Statement.
Corporate Information
We were incorporated in Delaware in 1997 as a wholly-owned subsidiary of R.J. Reynolds Tobacco Company. In August 2000, we became an independent company when we issued and sold stock to venture capital investors. On August 20, 2015, pursuant to the merger agreement between Targacept, Inc. and Catalyst Biosciences, Inc. (“Private
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Catalyst”), we acquired Private Catalyst and on August 20, 2015, we changed our name from Targacept, Inc. to Catalyst Biosciences, Inc. Our principal executive offices are located at 12730 High Bluff Drive, Suite 250, San Diego, CA 92130, and our telephone number is (650) 266-8674. Our website address is https://www.catalystbiosciences.com . We do not incorporate the information on, or accessible through, our website into this prospectus, and you should not consider any information on, or accessible through, our website as part of this prospectus.
We own various U.S. federal trademark registrations and applications and unregistered trademarks, including our corporate logo. This prospectus contains additional trade names, trademarks and service marks of ours and of other companies. We do not intend our use or display of other companies’ trade names, trademarks or service marks to imply a relationship with, or endorsement or sponsorship of us by, these other companies.
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THE OFFERING
Common Stock offered by the Selling Stockholders
1,240,442,745 shares of Common Stock.
Use of proceeds
We will not receive any proceeds from the sale of our Common Stock by the Selling Stockholders pursuant to this prospectus. See “Use of Proceeds” and “Selling Stockholders.”
Plan of distribution
The Selling Stockholders may sell all or a portion of the Resale Shares owned by them and offered hereby from time to time directly or through one or more underwriters, broker-dealers or agents. Registration of the Resale Shares covered by this prospectus does not mean, however, that such shares necessarily will be offered or sold. See “Plan of Distribution.”
Risk factors
Investing in our Common Stock involves a high degree of risk. See “Risk Factors” and other information included or incorporated into this prospectus for a discussion of the factors you should carefully consider before deciding to invest in our Common Stock.
Nasdaq symbol
Our Common Stock is currently listed on Nasdaq under the risk factorssymbol “CBIO.” We have applied to continue the listing of our Common Stock on Nasdaq under the symbol “GYRE” upon the completion of the Transactions.
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RISK FACTORS
Investing in this section,our Common Stock involves a high degree of risk. You should consider carefully the risks and uncertainties described in the section entitled “Risk Factors”“Risk Factors” contained in any prospectus supplement as well as our most recent Annual Report on Form10-K and the Proxy Statement, as well as any amendments thereto reflected in our Quarterly Reports on Form10-Q filed subsequent tofilings with the Annual Report on Form10-K,SEC, which are incorporated by reference into this prospectus and any prospectus supplement in their entirety, astogether with all of the sameother information contained in this prospectus or any document incorporated by reference herein and any free writing prospectus that we may be amended, supplemented or superseded from time to time by other reports we fileauthorize for use in connection with the SEC in the future. Each of thethis offering. The risks described in this prospectus or any document incorporated by reference herein are not the only risks facing us, but those that we consider to be material. There may be other unknown or unpredictable economic, business, competitive, regulatory or other factors that could have material adverse effects on our future results. Past financial performance may not be a reliable indicator of future performance, and historical trends should not be used to anticipate results or trends in future periods. If any of these sections and documents could materially and adversely affectrisks actually occurs, our business, financial condition, results of operations and prospects, andor cash flow could resultbe adversely affected, which could cause the trading price of our Common Stock to decline, resulting in a partialloss of all or complete losspart of your investment.
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USE OF PROCEEDS

Unless otherwise indicated in a

We are not selling any securities under this prospectus supplement,and we will not receive any proceeds from the sale of the Resale Shares covered hereby. The net proceeds from the sale of securitiesthe Resale Shares offered by this prospectus will be usedreceived by the Selling Stockholders.
Subject to limited exceptions, the Selling Stockholders will pay any underwriting discounts and commissions and expenses incurred by the Selling Stockholders for general corporate purposes, which may include clinical trials, researchbrokerage, accounting, tax or legal services or any other expenses incurred by the Selling Stockholders in disposing of any of the Resale Shares. We will bear the costs, fees and development activities, capital expenditures, selling, generalexpenses incurred in effecting the registration of the Resale Shares covered by this prospectus, including all registration and administrative costs, facilities expansion,filing fees, Nasdaq listing fees and fees and expenses of our counsel and our independent registered public accounting firm.
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SELLING STOCKHOLDERS
This prospectus relates to meet working capital needs. We expectthe resale by the Selling Stockholders from time to time of up to evaluate the acquisition of businesses, products and technologies for which a portion of the net proceeds may be used, although we currently are not planning or negotiating any such transactions. Pending such uses, we may invest the net proceeds in investment grade interest-bearing securities.

The amounts actually expended for each purpose may vary significantly depending upon numerous factors, including the amount and timing of the proceeds from this offering and progress with the commercial development of our products as well as our clinical development programs. Expenditures will also depend upon the establishment of collaborative arrangements with other companies, the availability of additional financing and other factors. Investors will be relying on the judgment of our management regarding the application of the proceeds of any sale of securities.

DESCRIPTION OF CAPITAL STOCK

The following description of our common stock and preferred stock, together with the additional information we include in any applicable prospectus supplements, summarizes the material terms and provisions of the common stock and preferred stock that we may offer under this prospectus. It may not contain all the information that is important to you. For the complete terms of our common stock and preferred stock, please refer to our Fourth Amended and Restated Certificate of Incorporation, as amended (the “restated certificate of incorporation”) and our amended and restated bylaws, which are incorporated by reference into the registration statement which includes this prospectus. The Delaware General Corporation Law (“DGCL”) may also affect the terms of these securities. While the terms we have summarized below will apply generally to any future common stock and preferred stock that we may offer, we will describe the particular terms of these securities in more detail in the applicable prospectus supplement. If we so indicate in a prospectus supplement, the terms of any security we offer under that prospectus supplement may differ from the terms we describe below.

Common Stock

Under our restated certificate of incorporation, we have authority to issue 100,000,0001,240,442,745 shares of our common stock, par value $0.001 per share. As of December 20, 2018, 11,947,738Common Stock, including shares of our common stock were issuedCommon Stock that are issuable to the Selling Stockholders pursuant to the Business Combination Agreement and outstanding. All shares of our common stock will, when issued, be duly authorized, fully paidCommon Stock that are issuable to the Selling Stockholders upon conversion of the Convertible Preferred Stock. The Selling Stockholders may from time to time offer and nonassessable.

Dividends.Subjectsell any or all of the Resale Shares set forth below pursuant to preferential dividend rightsthis prospectus and any accompanying prospectus supplement. When we refer to the “Selling Stockholders” in this prospectus, we mean the persons listed in the table below, and the pledgees, donees, transferees, assignees, successors, designees and others who later come to hold any of anythe Selling Stockholders’ interest in the Resale Shares other class or series of stock,than through a public sale.

Certain Information Concerning the holders ofSelling Stockholders
The table below presents information regarding the Selling Stockholders and the shares of our common stock are entitledCommon Stock that they may sell or otherwise dispose of from time to receive dividends, including dividends of our stock, as and when declared bytime under this prospectus.
In accordance with the F351 Agreement, on December 26, 2022, our board of directors subjectappointed two persons affiliated with GNI USA, Ying Luo, Ph.D. and Mr. Thomas Eastling, to any limitations imposed by lawour board as directors. Dr. Luo will serve as a Class I director with a term expiring at our 2025 annual meeting of the stockholders and until such time as his successor is duly elected and qualified, or until his earlier death, resignation or removal. Mr. Eastling will serve as a Class III director with a term expiring at our 2024 annual meeting of the stockholders and until such time as his successor is duly elected and qualified, or until his earlier death, resignation or removal. GNI USA, through entities affiliated with GNI Japan is a wholly-owned subsidiary of GNI Japan. Dr. Luo is a director, representative executive officer, president and chief executive officer and executive committee member of GNI Japan. Mr. Eastling is an outside member of GNI Japan and an advisor to the rightsexecutive committee of the holders, if any, of our preferred stock. We have never paid cash dividends on our common stock, except with respect to a cash dividend paid in connection with the closing of our business combination with Targacept, Inc. WeGNI Japan. Except as disclosed herein, other Selling Stockholders do not anticipate paying periodic cash dividendshave, and within the past three years have not had, any position, office or other material relationship with us.
For the Selling Stockholders collectively listed on our common stock for the foreseeable future. Any future determination abouttable below, we have calculated the paymentmaximum estimated number of dividends will be made at the discretion of our board of directors and will depend upon our earnings,Resale Shares that could become saleable by such Selling Stockholders pursuant to this prospectus if any, capital requirements, operating and financial conditions and on such other factors as the board of directors deems relevant.

Liquidation. In the event we are liquidated, dissolved or our affairs are wound up, after we pay or make adequate provision for all of our known debts and liabilities, each holder of our common stock will be entitledSelling Stockholders were to share ratably in all assets that remain, subject to any rights that are granted to the holders of any class or series of preferred stock.

Voting Rights. For all matters submitted to a vote of stockholders, each holder of our common stock is entitled to one vote for each share registered in his or her name. Except as may be required by law and in connection with some significant actions, such as mergers, consolidations, or amendments to our restated certificate of incorporation that affect the rights of stockholders, holders of our common stock vote together as a single class. There is no cumulative voting in the election of our directors, which means that, subject to any rights to elect directors that are granted to the holders of any class or series of preferred stock, a plurality of the votes cast at a meeting of stockholders at which a quorum is present is sufficient to elect a director.

Other Rights and Restrictions. Subject to the preferential rights of any other class or series of stock, allconvert their shares of our common stock have equal dividend, distribution, liquidation and other rights, and have no preference, appraisal or exchange rights, except for any appraisal rights provided by Delaware law. Furthermore, holders of our common stock have no conversion, sinking fund or redemption rights, or preemptive rights to subscribe for any of our securities. Our restated certificate of incorporation and our bylaws do not restrict the ability of a holder of our common stock to transfer his or herConvertible Preferred Stock into shares of our common stock.

Common Stock at a rate equal to $10,000 per share divided by the $1.00. On an aggregate basis, the total number of the Resale Shares saleable pursuant to this prospectus is 1,240,442,745 shares.

For purposes of the table below, we have assumed that the Selling Stockholders will not acquire beneficial ownership of any additional securities during the offering. The rights, powers, preferences and privileges of holdersfollowing table is prepared based on information provided to us by the Selling Stockholders. In addition, we assume that the Selling Stockholders have not sold, transferred or otherwise disposed of, our common stock are subjectCommon Stock in transactions exempt from the registration requirements of the Securities Act. Any changed or new information given to and may be adversely affectedus by the rightsSelling Stockholders, including regarding the identity of, holders of shares of any series of preferred stock which we may designate and issue in the future.

Listing. Our common stock is listed on the Nasdaq Capital Market under the symbol “CBIO.”

Transfer Agent and Registrar.The transfer agent for our common stock is American Stock Transfer &Trust Company, LLC. Its address is 6201 15th Avenue, Brooklyn, NY 11219.

Preferred Stock

Under our restated certificate of incorporation, we have authority, subject to any limitations prescribed by law and without further stockholder approval, to issue from time to time up to 5,000,000 shares of preferred stock, par value $0.001 per share, in one or more series. As of December 20, 2018, the Company had no shares of preferred stock issued and outstanding.

Pursuant to our restated certificate of incorporation, we are authorized to issue “blank check” preferred stock, which may be issued from time to time in one or more series upon authorization by our board of directors. Our board of directors, without further approval of the stockholders, is authorized to fix the designation, powers, preferences, relative, participating optional or other special rights, and any qualifications, limitations and restrictions applicable to each series of the preferred stock. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions and other corporate purposes could, among other things, adversely affect the voting power or rights of the holders of our common stock and, under certain circumstances, make it more difficult for a third party to gain control of us, discourage bids for our common stock at a premium or otherwise adversely affect the market price of the common stock.

The preferred stock will have the terms described below unless otherwise provided in the prospectus supplement relating to a particular series of the preferred stock. You should read the prospectus supplement relating to the particular series of the preferred stock being offered for specific terms, including:

the designation and stated value per share of the preferred stock and the number of shares offered;

the amount of liquidation preference per share;

the price at which the preferred stock will be issued;

the dividend rate, or method of calculation of any dividend, the dates on which dividends will be payable, whether dividends will be cumulative or noncumulative and, if cumulative, the dates from which dividends will accumulate;

any redemption or sinking fund provisions;

if other than the currency of the United States, the currency or currencies, including composite currencies, in which the preferred stock is denominated and/or in which payments will or may be payable;

any conversion provisions; and

any other rights, preferences, privileges, qualifications, limitations and restrictions on the preferred stock.

The preferred stock will, when issued, be duly authorized, fully paid and nonassessable. Unless otherwise specified in the prospectus supplement,securities held by, each series of the preferred stock will rank equally as to dividends and liquidation rights in all respects with any other series of preferred stock. The rights of holders of shares of each series of preferred stock will be subordinate to those of our general creditors.

Rank.Unless otherwise specified in the prospectus supplement, the preferred stock will, with respect to dividend rights and rights upon our liquidation, dissolution or winding up of our affairs, rank:

senior to all classes or series of our common stock and to all equity securities ranking junior to such preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs;

on a parity with all equity securities issued by us, the terms of which specifically provide that such equity securities rank on a parity with the preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs; and

junior to all equity securities issued by us, the terms of which specifically provide that such equity securities rank senior to the preferred stock with respect to dividend rights or rights upon our liquidation, dissolution or winding up of our affairs.

The term “equity securities” does not include convertible debt securities.

Dividends. Holders of the preferred stock of each series will be entitled to receive, when, as and if declared by our board of directors, cash dividends at such rates and on such dates described in the prospectus supplement. Different series of preferred stock may be entitled to dividends at different rates or based on different methods of calculation. The dividend rate may be fixed or variable or both. Dividends will be payable to the holders of record as they appear on our stock books on record dates fixed by our board of directors, as specified in the applicable prospectus supplement.

Dividends on any series of the preferred stock may be cumulative or noncumulative, as described in the applicable prospectus supplement. If our board of directors does not declare a dividend payable on a dividend payment date on any series of noncumulative preferred stock, then the holders of that noncumulative preferred stock will have no right to receive a dividend for that dividend payment date, and we will have no obligation to pay the dividend accrued for that period, whether or not dividends on that series are declared payable on any future dividend payment dates. Dividends on any series of cumulative preferred stock will accrue from the date we initially issue shares of such series or such other date specified in the applicable prospectus supplement.

Liquidation Preference.Upon any voluntary or involuntary liquidation, dissolution or winding up of our affairs, before we make any distribution or payment to the holders of any common stock or any other class or series of our capital stock ranking junior to the preferred stock in the distribution of assets upon any liquidation, dissolution or winding up of our affairs, the holders of each series of preferred stock shall be entitled to receive out of assets legally available for distribution to stockholders, liquidating distributions in the amount of the liquidation preference per share set forth in the applicable prospectus supplement, plus any accrued and unpaid dividends thereon. Such dividends will not include any accumulation in respect of unpaid noncumulative dividends for prior dividend periods. Unless otherwise specified in the prospectus supplement, after payment of the full amount of their liquidating distributions, the holders of preferred stock will have no right or claim to any of our remaining assets. Upon any such voluntary or involuntary liquidation, dissolution or winding up, if our available assets are insufficient to pay the amount of the liquidating distributions on all outstanding preferred stock and the corresponding amounts payable on all other classes or series of our capital stock ranking on parity with the preferred stock and all other such classes or series of shares of capital stock ranking on parity with the preferred stock in the distribution of assets, then the holders of the preferred stock and all other such classes or series of capital stock will share ratably in any such distribution of assets in proportion to the full liquidating distributions to which they would otherwise be entitled.

Redemption. If so provided in the applicable prospectus supplement, the preferred stock will be subject to mandatory redemption or redemption at our option, as a whole or in part, in each case upon the terms, at the times and at the redemption prices set forth in such prospectus supplement.

Voting Rights. Holders of preferred stock will have voting rights as required by law or as indicated in the applicable prospectus supplement.

Conversion Rights.The terms and conditions, if any, upon which any series of preferred stock is convertible into common stockSelling Stockholder, will be set forth in the applicable prospectus supplement relating thereto. Such terms will include the number of shares of common stock into which the shares of preferred stock are convertible, the conversion

price, rate or manner of calculation thereof, the conversion period, provisions as to whether conversion will be at our option or at the option of the holders of the preferred stock, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption.

Transfer Agent and Registrar. Any transfer agent and registrar for the preferred stock will be set forth in the applicable prospectus supplement.

Series A Convertible Preferred Stock

As of December 20, 2018, the Company had no shares of preferred stock issued and outstanding.

Liquidation Preference. In the event of a liquidation, the holders of Series A Convertible Preferred Stock will be entitled to participate on anas-converted-to-common-stock basis with holders of the common stock in any distribution of assets of the Company to the holders of the common stock.

Dividends. The Series A Certificate of Designation provides, among other things, that we shall not pay any dividends on shares of common stock (other than dividends in the form of common stock) unless and until such time as we pay dividends on each share of Series A Convertible Preferred Stock on anas-converted basis. Other than as set forth in the previous sentence, the Series A Certificate of Designation provides that no other dividends shall be paid on shares of Series A Convertible Preferred Stock and that we shall pay no dividends (other than dividends in the form of common stock) on shares of common stock unless we simultaneously comply with the previous sentence. The Series A Certificate of Designation does not provide for any restriction on the repurchase of Series A Convertible Preferred Stock by us while there is any arrearage in the payment of dividends on the Series A Convertible Preferred Stock. There are no sinking fund provisions applicable to the Series A Convertible Preferred Stock.

Voting Rights. With certain exceptions, as described in the Series A Certificate of Designation, the Series A Convertible Preferred Stock has no voting rights. However, as long as any shares of Series A Convertible Preferred Stock remain outstanding, the Series A Certificate of Designation provides that we shall not, without the affirmative vote of holders of a majority of the then-outstanding shares of Series A Convertible Preferred Stock, (a) alter or change adversely the powers, preferences or rights given to the Series A Convertible Preferred Stock or alter or amend the Series A Certificate of Designation, (b) increase the number of authorized shares of Series A Convertible Preferred Stock or (c) effect a stock split or reverse stock split of the Series A Convertible Preferred Stock or any like event.

Conversion. Each share of Series A Convertible Preferred Stock is convertible at any time at the holder’s option into a number of shares of Common Stock equal to $1,000.00 per share divided by the Conversion Price. The “Conversion Price” is initially $5.00, subject to adjustment for reverse and forward stock splits, stock dividends, stock combinations and other similar transactions as specified in the Certificate of Designation. Notwithstanding the foregoing, the Series A Certificate of Designation provides further that we shall not effect any conversion of the Series A Convertible Preferred Stock, with certain exceptions, to the extent that, after giving effect to an attempted conversion, the holder of Series A Convertible Preferred Stock (together with such holder’s affiliates, and any persons acting as a group together with such holder or any of such holder’s affiliates) would beneficially own a number of shares of Common Stock in excess of 4.99% (or, at the election of the purchaser, 9.99%) of the shares of our common stock then outstanding after giving effect to such exercise (the “Preferred Stock Beneficial Ownership Limitation”).

Call Right. Additionally, subject to certain exceptions, at any time prior to the three year anniversary of the issuance of the Series A Convertible Preferred Stock, subject to the Preferred Stock Beneficial Ownership Limitation, we will have the right to cause each holder of the Series A Convertible Preferred Stock to convert all or part of such holder’s Series A Convertible Preferred Stock in the event that (i) the volume weighted average price of our common stock for 30 consecutive trading days (the “Measurement Period”) exceeds 300% of the

conversion price of the Series A Convertible Preferred Stock issued (subject to adjustment for forward and reverse stock splits, recapitalizations, stock dividends and similar transactions), (ii) the average daily trading volume for such Measurement Period exceeds $500,000 per trading day and (iii) the holder is not in possession of any information that constitutes or might constitute, materialnon-public information which was provided by the Company and subject to the Preferred Beneficial Ownership Limitation. Our right to cause each holder of the Series A Convertible Preferred Stock to convert all or part of such holder’s Series A Convertible Preferred Stock shall be exercised ratably among the holders of the then outstanding Series A Convertible Preferred Stock.

Listing. We have not applied for listing of the Series A Convertible Preferred Stock on any securities exchange or other trading system.

Transfer Agent. The transfer agent for our Series A Convertible Preferred Stock is American Stock Transfer & Trust Company, LLC.

Certain Effects of Authorized but Unissued Stock

We have shares of common stock and preferred stock available for future issuance without stockholder approval. We may issue these additional shares for a variety of corporate purposes, including future public or private offerings to raise additional capital or to facilitate corporate acquisitions or for payment as a dividend on our capital stock. The existence of unissued and unreserved preferred stock may enable our board of directors to issue shares of preferred stock with terms that could render more difficult or discourage a third-party attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise, thereby protecting the continuity of our management. In addition, if we issue preferred stock, the issuance could adversely affect the voting power of holders of common stock and the likelihood that holders of common stock will receive dividend payments or payments upon liquidation.

ADDITIONAL INFORMATION CONCERNING OUR CAPITAL STOCK

Anti-Takeover Effects of Provisions of Our Charter Documents

Our restated certificate of incorporation provides for our board of directors to be divided into three classes serving staggered terms. Approximatelyone-third of our board of directors will be elected each year. The provision for a classified board could prevent a party who acquires control of a majority of the outstanding voting stock from obtaining control of the board of directors until the second annual stockholders meeting following the date the acquirer obtains the controlling stock interest. The classified board provision could discourage a potential acquirer from making a tender offer or otherwise attempting to obtain control of Catalyst and could increase the likelihood that incumbent directors will retain their positions. Our restated certificate of incorporation provides that directors may be removed with or without cause by the affirmative vote of the holders of at least 66 2/3% of the voting power of all outstanding stock.

Our restated certificate of incorporation requires that certain amendments to the restated certificate of incorporation and amendments by the stockholders of our bylaws require the affirmative vote of at least 66 2/3% of the voting power of all outstanding stock. These provisions could discourage a potential acquirer from making a tender offer or otherwise attempting to obtain control of the Company and could delay changes in management.

Our amended and restated bylaws establish an advance notice procedure for stockholder proposals to be brought before an annual stockholders meeting, including proposed nominations of persons for election to our board of directors. At an annual stockholders meeting, stockholders may only consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our board of directors. Stockholders may also consider a proposal or nomination by a person who was a stockholder of record on the record date for the meeting, who is entitled to vote at the meeting and who has given to the Secretary of the Company timely written notice, in proper form, of his or her intention to bring that business before the annual stockholders meeting. The amended and restated bylaws do not give our board of directors the power to approve or disapprove stockholder nominations of candidates or proposals regarding other business to be conducted at a special or annual meeting of the stockholders. However our bylaws may have the effect of precluding the conduct of business at a meeting if the proper procedures are not followed. These provisions may also discourage or deter a potential acquirer from conducting a solicitation of proxies to elect the acquirer’s own slate of directors or otherwise attempting to obtain control of the Company.

Our amended and restated bylaws provide that only our board of directors, the chairperson of the board, the President or the Chief Executive Officer may call a special meeting of stockholders. Because our stockholders do not have the right to call a special meeting, a stockholder could not force stockholder consideration of a proposal over the opposition of our board of directors by calling a special meeting of stockholders prior to such time as a majority of our board of directors, the chairperson of the board, the President or the Chief Executive Officer believed the matter should be considered or until the next annual meeting provided that the requestor met the notice requirements. The restriction on the ability of stockholders to call a special meeting means that a proposal to replace the board also could be delayed until the next annual stockholders meeting.

Our restated certificate of incorporation does not allow stockholders to act by written consent without a meeting. Without the availability of stockholder’s actions by written consent, a holder controlling a majority of our capital stock would not be able to amend our bylaws or remove directors without holding a stockholders’ meeting.

Anti-Takeover Effects of Provisions of Delaware Law

We are subject to the provisions of Section 203 of the DGCL, or Section 203. Under Section 203, we would generally be prohibited from engaging in any business combination with any interested stockholder for a period of three years following the time that this stockholder became an interested stockholder unless:

prior to this time, our board of directors approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;

upon completion of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding shares owned by persons who are directors and also officers, and by employee stock plans in which employee participants do not have the right to determine confidentially whether shares held subject to the plan will be tendered in a tender or exchange offer; or

at or subsequent to such time, the business combination is approved by our board of directors and authorized at a special or annual stockholders meeting, and not by written consent, by the affirmative vote of at least 66 2/3% of the outstanding voting stock that is not owned by the interested stockholder.

Under Section 203, a “business combination” includes:

any merger or consolidation involving the corporation and the interested stockholder;

any sale, transfer, pledge or other disposition of 10% or more of the assets of the corporation involving the interested stockholder;

any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder, subject to limited exceptions;

any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; or

the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 203 defines an interested stockholder as an entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by such entity or person.

Limitation of Liability and Indemnification

Our restated certificate of incorporation provides that our directors shall not be personally liable to us or our stockholders for monetary damages for any breach of fiduciary duty as a director, except for liability for breach of the director’s duty of loyalty to us or our stockholders, for acts or omissions not in good faith or involving intentional misconduct or a knowing violation of law, for payment of dividends or approval of stock purchases or redemptions that are prohibited by the DGCL, or for any transaction from which the director derived an improper personal benefit. Under the DGCL, our directors have a fiduciary duty to us that is not eliminated by this provision of the restated certificate of incorporation and, in appropriate circumstances, equitable remedies such as injunctive or other forms ofnon-monetary relief will remain available. This provision also does not affect our directors’ responsibilities under any other laws, such as federal securities laws or state or federal environmental laws.

Section 145 of the DGCL empowers a corporation to indemnify its directors and officers against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlements actually and reasonably incurred by them in connection with any action, suit or proceeding brought by third parties by reason of the fact that they were or are directors or officers of the corporation, if they acted in good faith, in a manner they reasonably believed to be in or not opposed to the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe that their conduct was unlawful. The DGCL provides further that the indemnification permitted thereunder shall not be deemed exclusive of any other rights to which the directors and officers may be entitled under the corporation’s bylaws, any agreement, a vote of stockholders or otherwise. Our restated certificate of incorporation provides that, to the fullest extent permitted by Section 145 of the DGCL, we shall indemnify any person who is or was a director or officer of us, or is or was serving at our request as a director, officer or trustee of another corporation, partnership, joint venture, trust, employee benefit

plan or other enterprise, against the expenses, liabilities or other matters referred to in or covered by Section 145 of the DGCL. Our amended and restated bylaws provide that we will indemnify any person who was or is a party or threatened to be made a party to any proceeding by reason of the fact that such person is or was a director or officer of us or is or was serving at our request as a director, officer or trustee of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise to the fullest extent permitted by the DGCL.

In addition, we have entered into indemnification agreements with each of our directors and with certain of our executive officers. Pursuant to the indemnification agreements, we has agreed to indemnify and hold harmless these directors and officers to the fullest extent permitted by the DGCL. The agreements generally cover expenses that a director or officer incurs or amounts that a director or officer becomes obligated to pay because of any proceeding to which he or she is made or threatened to be made a party or participant by reason of his or her service as a current or former director, officer, employee or agent of the Company. The agreements also provide for the advancement of expenses to the directors and officers subject to specified conditions. There are certain exceptions to our obligation to indemnify the directors and officers, including any intentional malfeasance or act where the director or officer did not in good faith believe he or she was acting in our best interests, with respect to “short-swing” profit claims under Section 16(b) of the 1934 Act and, with certain exceptions, with respect to proceedings that he or she initiates.

Section 145 of the DGCL also empowers a corporation to purchase insurance for its officers and directors for such liabilities. We maintain liability insurance for our officers and directors.

DESCRIPTION OF DEBT SECURITIES

The following description, together with the additional information we include in any applicable prospectus supplements, summarizes the material terms and provisions of the debt securities that we may offer under this prospectus. While the terms we have summarized below will apply generally to any future debt securities we may offer under this prospectus, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. The terms of any debt securities we offer under a prospectus supplement may differ from the terms we describe below.

The following summary description, together with the additional information we may include in any applicable prospectus supplements does not purport to be complete and is subject to, and qualified in its entirety by reference to, the form of indenture filed as an exhibit to the registration statement of which this prospectus is part, as it may be supplemented, amended or modified from time to time, as well as the notes and supplemental agreements relating to each series of debt securities that will be incorporated by reference as exhibits to the registration statement that includes this prospectus or as exhibits to a current report on Form8-K if we offer debt securities.

We will issue senior debt securities under one or more senior indentures that we will enter into with a trustee named in the relevant senior indenture. We will issue subordinated debt securities under one or more subordinated indentures that we will enter into with a trustee named in the relevant subordinated indenture. We have filed a form of indenture as an exhibitamendments to the registration statement of which this prospectus is a part. part, if and when necessary.

We usehave determined beneficial ownership in accordance with the terms “indenture”rules of the SEC. Beneficial ownership generally includes voting or investment power over securities. Except in cases where community property laws apply or as indicated in the footnotes to this table, to our knowledge, each Selling Stockholder identified in the table possesses sole voting and “indentures” ininvestment power over the Resale Shares shown as beneficially owned by the Selling Stockholder. The information is not necessarily indicative of beneficial ownership for any other purpose.
 
​​
Beneficial Ownership Prior to the Date of
this Prospectus
​​
Beneficial Ownership Assuming the
Sale of All Shares registered pursuant
to this Prospectus
Name
​​
Number of Shares
Beneficially Owned
Following
Conversion(1)
​​
Percent of
Outstanding
Common Stock(2)
​​
Number of
Shares
​​
Percent of
Outstanding
Common Stock
GNI USA(3)
​​
1,083,488,317
​​
85.17%
​​
0
​​
0%
Ping Lan(4)
​​
42,605,648
​​
3.35%
​​
0
​​
0%
Hui Sun(5)
​​
34,084,519
​​
2.68%
​​
0
​​
0%
Yueying Zhu(6)
​​
44,137,006
​​
3.47%
​​
0
​​
0%
Arthur Xin-bin Cheng(7)
​​
36,127,255
​​
2.84%
​​
0
​​
0%
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TABLE OF CONTENTS

(1)
One share of Convertible Preferred Stock converts into 10,000 shares of Common Stock.
(2)
Based upon 1,272,151,116 shares of Common Stock outstanding assuming the conversion of all shares of Convertible Preferred Stock that a Selling Stockholder beneficially owns into shares of Common Stock.
(3)
GNI USA, through entities affiliated with GNI Japan, is a wholly-owned subsidiary of GNI Japan. By virtue of such relationship, GNI Japan may be deemed to have voting and investment power with respect to the shares held by GNI USA. Ying Luo, Ph.D. is a director, representative executive officer, president and chief executive officer and executive committee member of GNI Japan and may be deemed to share voting and dispositive power over the shares held of record by GNI USA. The business address for GNI USA is 12730 High Bluff Drive, Suite 250, San Diego, California 92130. The address for GNI Japan and Ying Luo, Ph.D. is c/o GNI Group Ltd., Nihonbashi-Honcho YS Bldg. 3rd Floor 2-2-2 Nihonbashi-Honcho, Chuo-ku, 103-0023 Tokyo, Japan.
(4)
The business address for Ping Lan is c/o Beijing Continent Pharmaceuticals Co., Ltd, Room 320507-320509, Building 5, Wangjing SOHO Tower, Yard 1, Futong East Street, Chaoyang District, Beijing, PRC.
(5)
The business address for Hui Sun is c/o Beijing Continent Pharmaceuticals Co., Ltd, Room 320507-320509, Building 5, Wangjing SOHO Tower, Yard 1, Futong East Street, Chaoyang District, Beijing, PRC.
(6)
The business address for Yueying Zhu is c/o Beijing Continent Pharmaceuticals Co., Ltd, Room 320507-320509, Building 5, Wangjing SOHO Tower, Yard 1, Futong East Street, Chaoyang District, Beijing, PRC.
(7)
The business address for Arthur Xin-bin Cheng is c/o Beijing Continent Pharmaceuticals Co., Ltd, Room 320507-320509, Building 5, Wangjing SOHO Tower, Yard 1, Futong East Street, Chaoyang District, Beijing, PRC.
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TABLE OF CONTENTS

PLAN OF DISTRIBUTION
The Selling Stockholders may sell all or a portion of the Resale Shares covered by this prospectus from time to refer to both the senior indenture and the subordinated indenture.

time. The indenturesSelling Stockholders will be qualified under the Trust Indenture Actact independently of 1939, as amended. We use the term “debenture trustee” to refer to either the trustee under the senior indenture or the trustee under the subordinated indenture, as applicable.

The following summaries of material provisions of the senior debt securities, the subordinated debt securities and the indentures are subject to, and qualifiedus in their entirety by reference to, all the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplements related to the debt securities that we sell under this prospectus, as well as the indenture that would contain the terms of the debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture would be identical.

General

We will describe in each prospectus supplement the following terms relating to a series of debt securities:

the title;

the principal amount being offered, and if a series, the total amount authorized and the total amount outstanding;

any limit on the amount that may be issued;

whether or not we will issue the series of debt securities in global form, the terms and who the depositary will be;

the maturity date;

whether and under what circumstances, if any, we will pay additional amounts on any debt securities held by a person who is not a U.S. person for tax purposes, and whether we can redeem the debt securities if we have to pay such additional amounts;

the annual interest rate, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

the terms of the subordination of any series of subordinated debt;

the place where payments will be payable;

restrictions on transfer, sale or other assignment, if any;

our right, if any, to defer payment of interest and the maximum length of any such deferral period;

the date, if any, after which, and the price at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemptions provisions;

the date, if any, on which, and the price at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder’s option to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

whether the indenture will restrict our ability and/or the ability of our subsidiaries to:

incur additional indebtedness;

issue additional securities;

create liens;

pay dividends and make distributions in respect of our capital stock and the capital stock of our subsidiaries;

redeem capital stock;

place restrictions on our subsidiaries’ ability to pay dividends, make distributions or transfer assets;

make investments or other restricted payments;

sell or otherwise dispose of assets;

enter into sale-leaseback transactions;

engage in transactions with stockholders and affiliates;

issue or sell stock of our subsidiaries; or

effect a consolidation or merger;

whether the indenture will require us to maintain any interest coverage, fixed charge, cash flow-based, asset-based or other financial ratios;

a discussion of any material or special U.S. federal income tax considerations applicable to the debt securities;

information describing any book-entry features;

provisions for a sinking fund purchase or other analogous fund, if any;

whether the debt securities are to be offered at a price such that they will be deemed to be offered at an “original issue discount” as defined in paragraph (a) of Section 1273 of the Internal Revenue Code;

the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof; and

any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, including any additional events of default or covenants providedmaking decisions with respect to the debt securities,timing, manner and any terms thatsize of each sale. Such sales may be required by us or advisable under applicable laws or regulations.

Conversion or Exchange Rights

We will set forth in the prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for our common stock or our other securities. We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock or our other securities that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale

Any successor to or acquiror of the indentures must assume all of our obligations under the indentures or the debt securities, as appropriate. If the debt securities are convertible for our other securities or securities of other entities, the person with whom we consolidate or merge or to whom we sell all of our property must make provisions for the conversion of the debt securities into securities that the holders of the debt securities would have received if they had converted the debt securities before the consolidation, merger or sale.

Events of Default Under the Indenture

Unless otherwise provided in any applicable prospectus supplement, documents incorporated by reference or free writing prospectus, the following will be events of default under the indenture with respect to each series of debt securities issued thereunder:

(a)

if we fail to pay interest when due and payable and our failure continues for 30 days, or within such other time period as may be specified in the applicable indenture, and the time for payment has not been extended or deferred;

(b)

if we fail to pay the principal, premium or sinking fund payment, if any, when due and payable and the time for payment has not been extended or delayed;

(c)

if specified events of bankruptcy, insolvency or reorganization occur; and

(d)

if we fail to observe or perform any other covenant contained in the debt securities or the indentures, other than a covenant specifically relating to another series of debt securities, and our failure continues for 60 days, or within such other time period as may be specified in the applicable indenture, after we receive notice from the debenture trustee or holders of at least a majority in principal amount of the outstanding debt securities of an affected series, or such other percentage as may be specified in the applicable indenture, in aggregate principal amount of the outstanding debt securities of the applicable series.

If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the debenture trustee or the holders of at least 25%, or such other percentage as may be specified in the applicable indenture, in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the debenture trustee if notice is given by such holders, may declare the unpaid principal of, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the principal amount of and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the debenture trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indentures, if an event of default under an indenture shall occur and be continuing, the debenture trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the debenture trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the debenture trustee, or exercising any trust or power conferred on the debenture trustee, with respect to the debt securities of that series, provided that:

the direction so given by the holder is not in conflict with any law or the applicable indenture; and

subject to its duties under the Trust Indenture Act of 1939, the debenture trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

A holder of the debt securities of any series will only have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies if:

the holder has given written notice to the debenture trustee of a continuing event of default with respect to that series;

the holders of at least 25% (or, in the case of a default of the type described under subsection (d), above, a majority in principal amount of the outstanding debt securities of an affected series), or such other percentage as may be specified in the applicable indenture, in aggregate principal amount of the outstanding debt securities of that series have made written request, and such holders have offered reasonable indemnity to the debenture trustee to institute the proceeding as trustee; and

the debenture trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 60 days, or within such other time period as may be specified in the applicable indenture, after the notice, request and offer of indemnity.

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities.

We will periodically file statements with the debenture trustee regarding our compliance with specified covenants in the indentures.

Modification of Indenture; Waiver

We and the debenture trustee may change an indenture without the consent of any holders with respect to specific matters:

to evidence the succession of another corporation to us and the assumption by any such successor of our covenants in such indenture and in the debt securities issued thereunder;

to add to our covenants or to surrender any right or power conferred on us pursuant to the indenture;

to establish the form and terms of debt securities issued thereunder;

to evidence and provide for a successor trustee under such indenture with respect to one or more series of debt securities issued thereunder or to provide for or facilitate the administration of the trusts under such indenture by more than one trustee;

to cure any ambiguity, to correct or supplement any provision in the indenture that may be defective or inconsistent with any other provision of the indenture or to make any other provisions with respect to matters or questions arising under such indenture; provided that no such action adversely affects the interests of the holders of any series of debt securities issued thereunder in any material respect;

to add to, delete from or revise the conditions, limitations and restrictions on the authorized amount, terms or purposes of issue, authentication and delivery of securities under the indenture;

to add any additional events of default with respect to all or any series of debt securities;

to supplement any of the provisions of the indenture as may be necessary to permit or facilitate the defeasance and discharge of any series of debt securities, provided that such action does not adversely affect the interests of any holder of an outstanding debt security of such series or any other security in any material respect;

to make provisions with respect to the conversion or exchange rights of holders of debt securities of any series;

to pledge to the trustee as security for the debt securities of any series any property or assets;

to add guarantees in respect of the debt securities of one or more series;

to change or eliminate any of the provisions of the indenture, provided that any such change or elimination becomes effective only when there is no security of any series outstanding created prior to the execution of such supplemental indenture which is entitled to the benefit of such provision;

to provide for certificated securities in addition to or in place of global securities;

to qualify such indenture under the Trust Indenture Act of 1939, as amended;

with respect to the debt securities of any series, to conform the text of the indenture or the debt securities of such series to any provision of the description thereof in our offering memorandum or prospectus relating to the initial offering of such debt securities, to the extent that such provision, in our good faith judgment, was intended to be a verbatim recitation of a provision of the indenture or such securities; or

to make any other change that does not adversely affect the rights of holders of any series of debt securities issued thereunder in any material respect.

In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the debenture trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, we and the debenture trustee may only make the following changes with the consent of each holder of any outstanding debt securities affected:

extending the fixed maturity of the series of debt securities; or

reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption of any debt securities; or

reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver; or

make any change that adversely affects the right to convert or exchange any security into or for common stock or other securities, cash or other property in accordance with the terms of the applicable debt security.

Each indenture provides that we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

register the transfer or exchange of debt securities of the series;

replace stolen, lost or mutilated debt securities of the series;

maintain paying agencies;

hold monies for payment in trust;

recover excess money held by the debenture trustee;

compensate and indemnify the debenture trustee; and

appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the debenture trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

Each debt security will be represented by either one or more global securities registered in the name of The Depository Trust Company, as depositary, or a nominee (which we refer to, in the case of any debt security represented by a global debt security, as a “book-entry debt security”), or a certificate issued in definitive registered form (which we refer to, in the case of any debt security represented by a certificated security, as a “certificated debt security”) as set forth in the applicable prospectus supplement. Except as set forth in the applicable prospectus supplement, book-entry debt securities will not be issuable in certificated form.

You may transfer or exchange certificated debt securities at any office we maintain for this purpose in accordance with the terms of the indenture. No service charge will be made for any registration of transfer or exchange of certificated debt securities, but we may require payment of a sum sufficient to cover all taxes, assessments or other governmental charges that may be imposed in connection with a transfer or exchange.

You may effect the transfer of certificated debt securities and the right to receive the principal of, and any premium and interest on, certificated debt securities only by surrendering the certificate representing those certificated debt securities and either execution by us, and authentication and delivery by the debenture trustee, of the certificate to the new holder or execution by us, and authentication and delivery by the debenture trustee, of a new certificate to the new holder.

If we elect to redeem the debt securities of any series, we will not be required to:

issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days, or within such other time period as may be specified in the applicable indenture, before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

Repurchases on the Open Market

We, or an affiliate of ours, may at any time or from time to time repurchase any debt security in the open market or otherwise. Such debt securities may, at our option (or our affiliate’s option), be held, resold or surrendered to the trustee for cancellation.

Discharge of Debt Securities

When all outstanding debt securities of any series will become due and payable within one year of their stated maturity and we have deposited with the debenture trustee cash sufficient to pay and discharge all outstanding debt securities of such series on the date of their stated maturity, then we may discharge our obligations under the relevant indenture with respect to such debt securities while they remain outstanding.

Information Concerning the Debenture Trustee

The debenture trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the debenture trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the debenture trustee is under no obligation to exercise any of the powers given him or her by the indentures at the request of any holder of debt securities unless he or she is offered reasonable security and indemnity against the costs, expenses and liabilities that he or she might incur.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in a prospectus supplement, we will designate the corporate trust office of the debenture trustee in the City of New York as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the debenture trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

Governing Law

The indentures and the debt securities will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act of 1939 is applicable.

Subordination of Subordinated Debt Securities

The subordinated debt securities will be unsecured and will be subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in a prospectus supplement. The subordinated indenture does not limit the amount of subordinated debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

Outstanding Debt Securities

As of December 20, 2018, the Company had no outstanding debt securities.

DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. The terms of any warrants offered under that prospectus supplement may differ from the terms described below.

The following summary description, together with the additional information we may include in any applicable prospectus supplements does not purport to be complete and is subject to, and qualified in its entirety by reference to, the form of warrant agreement and form of warrant certificate relating to each series of warrants that will be incorporated by reference as an exhibit to the registration statement that includes this prospectus or as an exhibit to a current report on Form8-K if we offer warrants.

General

We will describe in the applicable prospectus supplement the terms of the series of warrants, including:

the offering price and aggregate number of warrants offered;

the currency for which the warrants may be purchased;

if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;

if applicable, the date on and after which the warrants and the related securities will be separately transferable;

in the case of warrants to purchase common stock, the number of shares of common stock purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;

the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreements and the warrants;

the terms of any rights to redeem or call the warrants;

any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;

the dates on which the right to exercise the warrants will commence and expire;

the manner in which the warrant agreements and warrants may be modified;

federal income tax consequences of holding or exercising the warrants;

the terms of the securities issuable upon exercise of the warrants; and

any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including the right to receive dividends, if any, or, payments upon our liquidation, dissolution or winding up or to exercise voting rights, if any.

Exercise of Warrants

Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise

specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to 5:00 P.M. Eastern Time on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Enforceability of Rights by Holders of Warrants

Any warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

Form, Exchange, and Transfer

We may issue the warrants in registered form or bearer form. Warrants issued in registered form, i.e., book-entry form, will be represented by a global security registered in the name of a depository, which will be the holder of all the warrants represented by the global security. Those investors who own beneficial interests in a global warrant will do so through participants in the depository’s system, and the rights of these indirect owners will be governed solely by the applicable procedures of the depository and its participants. In addition, we may issue warrants innon-global form, i.e., bearer form. If any warrants are issued innon-global form, warrant certificates may be exchanged for new warrant certificates of different denominations, and holders may exchange, transfer, or exercise their warrants at the warrant agent’s office or any other office indicated in the applicable prospectus supplement or other offering material.

Outstanding Warrants

As of December 20, 2018, we have outstanding warrants to purchase common stock as follows: (i) at any time until the5-year anniversary of the original date of issuance in 2014, warrants to purchase an aggregate of 2,313 shares of our common stock at an exercise price of $499.05 per share, (ii) at any time until the5-year anniversary of the original date of issuance in 2015, as applicable, warrants to purchase an aggregate of 7,772 shares of our common stock at an exercise price of $49.91 per share and warrants to purchase an aggregate of 24 shares of our common stock at an exercise price of $499.05 per share, and (iii) at any time until the7-year anniversary of the original date of issuance in 2012, warrants to purchase an aggregate of 85 shares of our common stock at an exercise price of $392.70 per share. Effective November 13, 2018, Healthcare Ventures VIII, L.P. agreed to cancel outstanding warrants representing the right to purchase up to an aggregate 1,845 shares of the Company’s common stock (as adjusted for the 15:1 reverse stock split effected February 10, 2017).

DESCRIPTION OF UNITS

The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the units that we may offer under this prospectus. While the terms we have summarized below will apply generally to any units that we may offer under this prospectus, we will describe the particular terms of any series of units in more detail in the applicable prospectus supplement. The terms of any units offered under a prospectus supplement may differ from the terms described below.

The following summary description, together with the additional information we may include in any applicable prospectus supplements does not purport to be complete and is subject to, and qualified in its entirety by reference to, the form of unit agreement and form of unit certificate relating to each series of units that will be incorporated by reference as an exhibit to the registration statement that includes this prospectus or as an exhibit to a current report on Form8-K if we offer units.

General

We may issue units comprised of common stock, preferred stock, debt securities, debt obligations of third parties, including U.S. treasury securities, warrants or any combination thereof. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date.

We will describe in the applicable prospectus supplement the terms of the series of units, including:

the designation and terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;

any provisions of the governing unit agreement that differ from those described below; and

any provisions for the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units.

The provisions described in this section, as well as those described under “Description of Capital Stock,” “Description of Debt Securities” and “Description of Warrants” will apply to each unit and to any common stock, preferred stock, debt security or warrants included in each unit, respectively.

Issuance in Series

We may issue units in such amounts and in such numerous distinct series as we determine.

Enforceability of Rights by Holders of Units

Any unit agent will act solely as our agent under the applicable unit agreement and will not assume any obligation or relationship of agency or trust with any holder of any unit. A single bank or trust company may act as unit agent for more than one series of units. A unit agent will have no duty or responsibility in case of any default by us under the applicable unit agreement or unit, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a unit may, without the consent of the related unit agent or the holder of any other unit, enforce by appropriate legal action its rights as holder under any security included in the unit.

Title

We, any unit agents and any of their agents may treat the registered holder of any unit certificate as an absolute owner of the units evidenced by that certificate for any purpose and as the person entitled to exercise the rights attaching to the units so requested, despite any notice to the contrary. See “Legal Ownership of Securities” below.

Outstanding Units

We have no outstanding units.

PLAN OF DISTRIBUTION

We may sell the securities being offered by this prospectus separately or together through any of the following methods:

todirectly or through one or more underwriters, broker-dealers or dealersagents. If the Resale Shares are sold through underwriters or broker-dealers, the Selling Stockholders will be responsible for underwriting discounts or commissions or agent’s commissions. The Resale Shares may be sold on any national securities exchange or quotation service on which the securities may be listed or quoted at the time of sale, in a public offeringthe over-the-counter market or in transactions otherwise than on these exchanges or systems or in the over-the-counter market and in one or more transactions at fixed prices, at prevailing market prices at the time of the sale, by them;

directly to investors;

through agents;

throughat varying prices determined at the time of sale, or at negotiated prices. These sales may be effected in transactions, which may involve crosses or block tradestransactions. The Selling Stockholders may use any one or more of the following methods when selling the Resale Shares:

on the Nasdaq, in the over-the-counter market or on any other national securities exchange on which our securities are listed or traded;
in privately negotiated transactions;
in underwritten offerings;
in ordinary brokerage transactions and transactions in which the broker or dealer engaged to handlebroker-dealer solicits purchasers;
in a block trade in which the block tradebroker-dealer will attempt to sell the securitiesoffered shares as agent but may position and resell a portion of the block as principal to facilitate the transaction;

through any combination if these methodspurchases by a broker-dealer as principal and resale by the broker-dealer for its account pursuant to this prospectus;

through the writing of sale;options (including put or

in any manner, as provided in call options), whether the applicable prospectus supplement.

We may distribute securities from time to time in oneoptions are listed on an options exchange or more transactions:

otherwise;

at a fixed price or prices, which may be changed;

at market prices prevailing atthrough the times of sale;

at prices related to such prevailing market prices; or

at negotiated prices.

We will describe the method of distribution of the securities shares by any Selling Stockholder to its partners, members or stockholders;

in short sales entered into after the effective date of the registration statement of which this prospectus is a part;
by pledge to secured debts and other obligations;
through delayed delivery arrangements;
an exchange distribution in accordance with the rules of the applicable exchange;
through delayed delivery arrangements;
to or through underwriters or agents;
“at the market” or through market makers or into an existing market for the securities;
through trading plans entered into by a Selling Stockholder pursuant to Rule 10b5-1 under the Exchange Act that are in place at the time of an offering pursuant to this prospectus supplement. Weand any applicable prospectus supplement hereto that provide for periodic sales of securities on the basis of parameters described in such trading plans; or
a combination of any such methods of sale.
The Selling Stockholders also may also determine the priceresell all or other termsa portion of the securities offeredResale Shares in open market transactions in reliance upon Rule 144 under the Securities Act, as permitted by that rule, or Section 4(a)(1) under the Securities Act, if available, rather than under this prospectus, provided that they meet the criteria and conform to the requirements of those provisions.
Broker-dealers engaged by use of an electronic auction. We will describe how any auction will determine the price or anySelling Stockholders may arrange for other terms, how potential investors maybroker-dealers to participate in sales. If the auction andSelling Stockholders effect such transactions by selling the nature of the obligations of the underwriter, dealerResale Shares to or agent in the applicable prospectus supplement.

Unless otherwise specified in the applicable prospectus supplement, each classthrough underwriters, broker-dealers or series of securities will be a new issue with no established trading market, other than our common stock, which is traded on The Nasdaq Capital Market. We may elect to list any other class or series of securities on any exchange, but we are not obligated to do so. It is possible that one or moreagents, such underwriters, may make a market in a class or series of securities, but the underwriters will not be obligated to do so and may discontinue any market making at any time without notice. We cannot give any assurance as to the liquidity of the trading market for any of the securities.

Underwriters, dealersbroker-dealers or agents may receive compensation in the form of discounts, concessions or commissions from us or our purchasers (as their agents in connection with the sale of the securities). In addition, underwriters may sell the securities to or through dealers, and those dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters and/Selling Stockholders or commissions from purchasers of the purchasersResale Shares for whom they may act as agent. These underwriters, dealersagent or to whom they may sell as principal. Such commissions will be in amounts

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to be negotiated, but, except as set forth in a supplement to this prospectus, in the case of an agency transaction will not be in excess of a customary brokerage commission in compliance with FINRA Rule 2121; and in the case of a principal transaction a markup or markdown in compliance with FINRA Rule 2121.01.
The Selling Stockholders may transfer and donate the Resale Shares in other circumstances in which case the transferees, donees or pledgees will be the selling beneficial owners for purposes of this prospectus.
Any broker-dealer or agents participating in the distribution of the Resale Shares may be considereddeemed to be underwriters under“underwriters” within the meaning of Section 2(11) of the Securities Act. As a result, discounts,Act in connection with such sales. In such event, any commissions paid, or profits on resale received by the underwriters, dealers or agents may be treated as underwriting discounts and commissions. The prospectus supplement will identify any such underwriter, dealer or agent, and describe any compensation received by them from us. Only underwriters named in the prospectus supplement are underwriters of the securities offered by the prospectus supplement. Any initial public offering price and any discounts or concessions allowed to, any such broker-dealer or reallowed or paid to dealersagent and any profit on the resale of the Resale Shares purchased by them may be changed from timedeemed to time.

Webe underwriting commissions or discounts under the Securities Act.

The Selling Stockholders may also sell our securities short and deliver the securities to close out their short positions or loan or pledge the securities to broker-dealers that in turn may sell the securitiessecurities. The shares may be sold directly or through agents we designate from timebroker-dealers acting as principal or agent or pursuant to time. We will name any agent involveda distribution by one or more underwriters on a firm commitment or best-efforts basis. The Selling Stockholders may also enter into hedging transactions with broker-dealers. In connection with such transactions, broker-dealers of other financial institutions may engage in short sales of our securities in the offering and salecourse of hedging the positions they assume with the Selling Stockholders. The Selling Stockholders may also enter into options or other transactions with broker-dealers or other financial institutions, which require the delivery to such broker-dealer or other financial institution of securities offered by this prospectus, which securities such broker-dealer or other financial institution may resell pursuant to this prospectus (as supplemented or amended to reflect such transaction).
Each Selling Stockholder has informed the Company that it is not a registered broker-dealer and we will describedoes not have any commissions we will paywritten or oral agreement or understanding, directly or indirectly, with any person to distribute the agentResale Shares. Upon the Company being notified in the prospectus supplement. Unless the prospectus supplement states otherwise, our agent will act onwriting by a best-efforts basisSelling Stockholder that any material arrangement has been entered into with a broker-dealer for the period of its appointment.

We may authorize agentsResale Shares through a block trade, special offering, exchange distribution or underwriterssecondary distribution or a purchase by a broker or dealer, a supplement to solicit offers by certain types of institutional investors to purchase securities from us at the public offering price set forth in thethis prospectus supplementwill be filed, if required, pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.

Underwriters, dealers and agents may be entitled to indemnification by us against certain civil liabilities, including liabilitiesRule 424(b) under the Securities Act, disclosing (i) the name of each such Selling Stockholder and of the participating broker-dealer(s), (ii) the number of Resale Shares involved, (iii) the price at which the Resale Shares were sold, (iv) the commissions paid or discounts or concessions allowed to contribution with respectsuch broker-dealer(s), where applicable, (v) that such broker-dealer(s) did not conduct any investigation to payments madeverify the information set out or incorporated by reference in this prospectus, and (vi) other facts material to the underwriters, dealerstransaction.

Under the securities laws of some U.S. states, shares of our Common Stock may be sold in such states only through registered or agents, under agreements between uslicensed brokers or dealers. In addition, in some U.S. states shares of our Common Stock may not be sold unless such shares have been registered or qualified for sale in such state or an exemption from registration or qualification is available and is complied with.
There can be no assurance that any Selling Stockholder will sell any or all of the underwriters, dealersResale Shares registered pursuant to the shelf registration statement, of which this prospectus is a part.
Each Selling Stockholder and agents.

Anyany other person participating in thesuch distribution of common stock registered under the registration statement that includes this prospectus will be subject to applicable provisions of the Exchange Act and the applicable SEC rules and regulations thereunder, including, among others,without limitation, to the extent applicable, Regulation M of the Exchange Act, which may limit the timing of purchases and sales of any of our common stockthe Resale Shares by the Selling Stockholder and any suchother participating person. Furthermore,To the extent applicable, Regulation M may also restrict the ability of any person engaged in the distribution of our common stockthe Resale Shares to engage in market-making activities with respect to our common stock. These restrictionsthe Resale Shares. All of the foregoing may affect the marketability of our common stockthe Resale Shares and the ability of any person or entity to engage in market-making activities with respect to our common stock.

We may grant underwriters who participate in the distributionResale Shares.

The Selling Stockholders will pay all of the securities an option to purchase additional securities to cover overallotments, if any,expenses incurred in connection with the distribution. Any underwriter may engage in overallotment, stabilizing transactions, short-covering transactions and penalty bids in accordance with Regulation M that stabilize, maintain or otherwise affect the priceregistration of the offered securities. Overallotment involves salesResale Shares, including, without limitation, SEC filing fees and expenses of compliance with state securities or “blue sky” laws, all underwriting discounts and selling commissions, if any, and any legal or other expenses incurred by us or them in excessconnection with the registration and offer and sale of the offering size,Resale Shares.
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DIVIDEND POLICY
On September 20, 2022, we paid a special, one-time cash dividend of approximately $45.0 million (or $1.43 per share) to our common stockholders of record as of the close of business on September 6, 2022. On January 12, 2023, we paid a special, one-time cash dividend of approximately $7.6 million (or $0.24 per share) to our common stockholders of record as of the close of business on January 5, 2023. In June 2023, we distributed $3.5 million, which createreflected, in connection with the Vertex Transaction, the hold-back amount received from Vertex less expenses and a short position. Stabilizing transactions permit bidsreserve for potential tax liabilities, to purchase the underlying security so long as the stabilizing bidsCVR Holders. We currently intend to retain all future earnings, if any, for use in our business and do not exceed a specified maximum. Short covering transactions involve purchases of theanticipate paying any cash dividends on our common stock in the open market afterforeseeable future. Any future determination to declare cash dividends will be made at the distribution is completeddiscretion of our board of directors, subject to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the common stock originally sold by the dealer is purchased in a covering transaction to cover short positions. Those activitiesapplicable laws, and will depend on our financial condition, results of operations, capital requirements, general business conditions and other factors our board of directors may cause the pricedeem relevant.
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LEGAL MATTERS
The validity of the common stock to be higher than it would otherwise be. If commenced, the underwriters may discontinue anyissuance of the activities at any time. If any such activities will occur, theyResale Shares offered by this prospectus has been passed upon for us by Orrick, Herrington & Sutcliffe LLP, New York, New York. Certain legal matters in connection with the Resale Shares offered hereby will be describedpassed on for any agents, dealers or underwriters by counsel that will be named in the applicable prospectus supplement.

Underwriters or agents and their associates may be customers of, engage in transactions with or perform services for us in the ordinary course of business and any such relationships will be described in the applicable prospectus supplement.

To the extent required, this prospectus may be amended or supplemented from time to time to describe a specific plan of distribution.

18
LEGAL MATTERS

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The validity of the securities being offered by this prospectus will be passed upon by Morrison & Foerster LLP of Palo Alto, California. Additional legal matters may be passed upon for us or any underwriters, dealers or agents, by counsel that we will name in an applicable prospectus supplement.

EXPERTS

The consolidated balance sheets of Catalyst Biosciences, Inc. and Subsidiary as of December 31, 20172022 and 2016,2021, and the related consolidated statements of operations, comprehensive loss, redeemable convertible preferred stock and stockholders’ equity (deficit), and cash flowscashflows for each of the years then ended, have been audited by EisnerAmper LLP, independent registered public accounting firm, as stated in their report, which is incorporated herein by reference.reference, which report includes an explanatory paragraph about the existence of substantial doubt concerning the Company’s ability to continue as a going concern. Such financial statements have been incorporated herein by reference in reliance on the report of such firm given upon their authority as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION

We are a reporting companyThe consolidated financial statements of Beijing Continent Pharmaceuticals Co., Ltd. at December 31, 2022 and file annual, quarterly2021, and current reports, proxy statements and other information with the Securities and Exchange Commission, or the SEC. You may read and copy these reports, proxy statements and other information at the SEC’s public reference rooms at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. You can request copies of these documents by writing to the SEC and paying a fee for the copying cost. Please call the SEC at1-800-SEC-0330 for more information about the operationeach of the public reference rooms. Our SEC filingsyears then ended, which are also available at the SEC’s website at www.sec.gov and our website at www.catalystbiosciences.com. We have not incorporated by reference intoin this prospectus the information contained on our websiteProspectus and you should not consider it to be part of this prospectus. In addition, you can readRegistration Statement, have been audited by Ernst & Young Hua Ming LLP, independent registered public accounting firm, as set forth in their report thereon, including therein, and copy our SEC filings at the office of the National Association of Securities Dealers, Inc. at 1735 K Street, Washington, D.C. 20006.

We have filed a registration statement on FormS-3 with the SEC relating to the securities covered by this prospectus. This prospectus is a part of the registration statement and does not contain all of the information in the registration statement. You may review a copy of the registration statement at the SEC’s public reference room in Washington, D.C., as well as through the SEC’s Internet site at www.sec.gov.

The SEC allows us to “incorporate by reference” the information we file with it, which means that we can disclose important information to you by referring you to those documents. The informationare incorporated herein by reference is considered to be partin reliance upon such report given on the authority of this prospectus. In addition, information we file withsuch firm as experts in accounting and auditing.

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1,240,442,745 Shares

COMMON STOCK

Offered by the SEC in the future will automatically update and supersede information contained in this prospectus and any accompanying prospectus supplement.

This prospectus incorporates by reference the documents set forth below that we have previously filed with the SEC:

Selling Stockholders

our Annual Report on Form10-K for the fiscal year ended December 31, 2017 filed with the SEC on March 19, 2018;

our Quarterly Reports on Form10-Q for the quarterly periods ended March 31, 2018, June 30, 2018 and September 30, 2018 filed with the SEC on May 3, 2018, August 2, 2018 and November 1, 2018, respectively; and

PROSPECTUS

our Current Reports on Form8-K filed with the SEC on April 13, 2018, June 14, 2018, June 18, 2018, July 18, 2018, August 15, 2018, August 31, 2018 and December 18, 2018.

All filings filed by us pursuant to the Exchange Act after the

The date of the initial filing of the registration statement of which this prospectus is a part and prior to effectiveness of the registration statement shall be deemed to be incorporated by reference into this prospectus.

We also incorporate by reference into this prospectus additional documents that we may file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, excluding, in each case, information deemed furnished and not filed until we sell all of the securities we are offering. Any statements contained in a previously filed document incorporated by reference into this prospectus is deemed to be modified or superseded for purposes of this prospectus        to the extent that a statement contained in this prospectus, or in a subsequently filed document also incorporated by reference herein, modifies or supersedes that statement., 2023

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We will provide to you at no cost a copy of any and all of the information incorporated by reference into the registration statement of which this prospectus is a part. You may make a request for copies of this information in writing or by telephone. Requests should be directed to:

Catalyst Biosciences, Inc.

611 Gateway Blvd. Suite 710

South San Francisco, CA 94080

Attn: Fletcher Payne, Chief Financial Officer

(650)871-0761

PART II


INFORMATION NOT REQUIRED IN PROSPECTUS

ItemITEM 14.

Other expensesExpenses of issuanceIssuance and distribution

Distributions.

The following table sets forth allthe expenses other than the underwriting discounts and commissions, payableto be borne by usCatalyst Biosciences, Inc. in connection with the offerings described in this offering. All the amounts shown are estimates except for the registration fee.

SEC registration fee

  $24,240 

FINRA fee

   * 

Accounting fees and expenses

   * 

Legal fees and expenses

   * 

Transfer agent and registrar fees

   * 

Printing expenses

   * 

Miscellaneous

   * 
  

 

 

 

Total

  $24,240* 
  

 

 

 

Registration Statement.
Registration fee – Securities and Exchange Commission
​​
$57,152.93
Printing and engraving expenses
​​
*
Legal fees and expenses
​​
*
Accounting fees and expenses
​​
*
Transfer agent fees and expenses
​​
*
Miscellaneous
​​
Total
​​
*
*

The applicable prospectus supplement will set forthThese fees are calculated based on the estimated aggregate amountsecurities offered and the number of expenses payable in respect of any offering of securities.

issuances and accordingly cannot be defined at this time.

ItemITEM 15.

Indemnification of Directors and Officers

Officers.

Our Fourth Amended

Section 145 of the Delaware General Corporation Law authorizes a court to award, or a corporation’s board of directors to grant, indemnity to directors and Restated Certificateofficers under certain circumstances and subject to certain limitations. The terms of Incorporation,Section 145 of the Delaware General Corporation Law are sufficiently broad to permit indemnification under certain circumstances for liabilities, including reimbursement of expenses incurred, arising under the Securities Act of 1933, as amended, or the Securities Act.
As permitted by the Delaware General Corporation Law, our restated certificate of incorporation and as may be further amended and in effect from timerestated bylaws contain provisions relating to time, which we refer to as the limitation of liability and indemnification of directors and officers. The restated certificate of incorporation provides that our directors shallwill not be personally liable to us or our stockholders for monetary damages for any breach of fiduciary duty as a director, except for liability liability:
for any breach of the director’s duty of loyalty to us or our stockholders, stockholders;
for acts or omissions not in good faith or involvingwhich involve intentional misconduct or a knowing violation of law, for paymentlaw;
under Section 174 of dividends or approval of stock purchases or redemptions that are prohibited by the Delaware General Corporation Law of the State of Delaware, as amended, which we refer to as the DGCL,Law; or
for any transaction from which the director derived an improper personal benefit. Under the DGCL, our directors have a fiduciary duty to us that is not eliminated by this provision of the
Our restated certificate of incorporation and, in appropriate circumstances, equitable remedies such as injunctivealso provides that if the Delaware General Corporation Law is amended to authorize corporate action further eliminating or other formslimiting the personal liability ofnon-monetary relief directors, then the liability of our directors will remain available. This provision also does not affect our directors’ responsibilities under any other laws, such as federal securities lawsbe eliminated or state or federal environmental laws.

Section 145 of the DGCL empowers a corporation to indemnify its directors and officers against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlements actually and reasonably incurred by them in connection with any action, suit or proceeding brought by third parties by reason of the fact that they were or are directors or officers of the corporation, if they acted in good faith, in a manner they reasonably believed to be in or not opposed to the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe that their conduct was unlawful. The DGCL provides further that the indemnification permitted thereunder shall not be deemed exclusive of any other rights to which the directors and officers may be entitled under the corporation’s bylaws, any agreement, a vote of stockholders or otherwise. The restated certificate of incorporation provides that,limited to the fullest extent permitted by Section 145the Delaware General Corporation Law as so amended.

Our amended and restated bylaws provide that we will indemnify our directors and officers to the fullest extent permitted by Delaware law, as it now exists or may in the future be amended (but, in the case of any amendment, only to the DGCL,extent such amendment permits broader indemnification rights than such law permitted us prior to such amendment), against all expenses reasonably incurred in connection with their service for or on our behalf. Our amended and restated bylaws provide that we shall indemnify any person who is or wasadvance the expenses incurred by a director or officer in advance of us,the final disposition of an action or proceeding; provided, however, that if the Delaware General Corporation Law so requires, an advancement of expenses incurred by an indemnitee in his or her capacity as a director or officer (and not in any other capacity in which service was or is rendered by such indemnitee, including without limitation, service to an employee benefit plan) will be made only upon delivery to us of an undertaking, by or wason behalf of such indemnitee, to repay all amounts so advanced if it is ultimately determined that such indemnitee is not entitled to be indemnified by us under our amended and restated bylaws or otherwise. Our amended and restated bylaws permit us to secure insurance on behalf of any director, officer, employee, or agent or individual serving at ourthe request of us as a director, officer, employee or trusteeagent of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise against any liability asserted against such person and incurred by such person in any such capacity, or arising out of such person’s status as such, whether or not we would have the expenses, liabilitiespower or other matters referredthe obligation to in or covered by Section 145indemnify such person against such liability under the provisions of the DGCL. Ourour amended and restated bylaws providebylaws.
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We have entered into indemnification agreements with each of our directors and with each executive officer. Pursuant to the indemnification agreements, we have agreed to indemnify and hold harmless these directors and officers to the fullest extent permitted by the Delaware General Corporation Law. The agreements generally cover expenses that we will indemnifya director or officer incurs or amounts that a director or officer becomes obligated to pay because of any person who wasproceeding to which he or she is a partymade or threatened to be made a party to any proceeding by reason of the fact that such person is or was a director or officer of us or is or was serving at our request as a director, officer or trustee of another corporation, partnership, joint venture, trust, employee benefit plan or other enterprise to the fullest extent permitted by the DGCL. In addition, we have entered into agreements with each of our directors and officers under which, among other

II-1

things, we have agreed to indemnify the director or officer against expenses incurred in any proceeding, including any action by us, in which the director or officer was, is or is threatened to be made a party or a participant by reason of his or her statusservice as a presentcurrent or former director, officer, employee or agent of usour company. The agreements also provide for the advancement of expenses to the directors and officers subject to specified conditions. There are certain exceptions to our obligation to indemnify the directors and officers, including any intentional malfeasance or atact where the director or officer did not in good faith believe he or she was acting in our request, any other corporation, partnership, joint venture, trust, employee benefit planbest interests, with respect to “short-swing” profit claims under Section 16(b) of the Exchange Act and, with certain exceptions, with respect to proceedings that he or other enterprise. At present, there is no pending litigation or proceeding involvingshe initiates.

We maintain insurance policies that indemnify our directors and officers against various liabilities arising under the Securities Act and the Exchange Act of 1934, as amended, that might be incurred by any director or officer in his capacity as to which indemnification will be required or permitted, and we are not aware of any threatened litigation or proceeding that may result in a claim for such indemnification.

Section 145 of the DGCL also empowers a corporation to purchase insurance for its officers and directors for such liabilities. We maintain liability insurance for our officers and directors.

Any underwriting agreements that we may enter into will likely provide for the indemnification of us, our controlling persons, our directors and certain of our officers by the underwriters against certain liabilities, including liabilities under the Securities Act.

such.
ItemITEM 16.

Exhibits and Financial Statement Schedules

Exhibits.

(a)

The following exhibits are filed herewith or incorporated​

​
​​
Incorporated by reference herein by reference:

​​

Exhibit

Number


No.
​

​

Description

​​
Form
​​
File No.
​​
Filing Date
​​
Filed
Herewith
2.1
​​
Asset Purchase Agreement, dated December 26, 2022, by and among Catalyst Biosciences, Inc., GNI Japan, and GNI Hong Kong Limited
​​
8-K
​​
000-51173
​​
December 27, 2022
​​
  1.1
2.2
​Form of Underwriting Agreement (for Common Stock)*
​
  1.2Form of Underwriting Agreement (for Preferred Stock)*
  1.3Form of Underwriting Agreement (for Debt Securities)*
  1.4Form of Underwriting Agreement (for Warrants)*
  1.5Form of Underwriting Agreement (for Units)*
  2.1
Agreement and Plan of MergerAmendment to Asset Purchase Agreement, dated as of March 5, 2015,29, 2023, by and among Targacept, Inc.,Catalyst, GNI Japan and GNI Hong Kong Limited.
​​
8-K
​​
000-51173
​​
March 30, 2023
​​
2.3
​​
Business Combination Agreement, dated December 26, 2022, by and among Catalyst Biosciences, Inc., GNI USA, Inc., GNI Japan, GNI Hong Kong Limited, Shanghai Genomics, Inc., the individuals listed on Annex A thereto and Talos Merger Sub,Continent Pharmaceuticals Inc. (incorporated by reference to Exhibit 2.1 to the Company’s Current Report on Form
​​
8-K as filed with the SEC on March 6, 2015)
​​
000-51173
​​
December 27, 2022
​​
2.4
  2.2​​
Amendment No. 1 to Business Combination Agreement, and Plandated as of MergerMarch 29, 2023, by and among Targacept,Catalyst, GNI USA, GNI Japan, GNI Hong Kong Limited, Shanghai Genomics Inc., Talos Merger Sub, Inc.,the Minority Holders and Catalyst dated May  6, 2015 (incorporated by reference to Exhibit 10.1 to the Company’s Current Report on FormCPI.
​​
8-K as filed with the SEC on May 12, 2015)
​​
000-51173
​​
March 30, 2023
​​
2.5
​​
Second Amendment to Business Combination Agreement, dated as of August 30, 2023, by and among Catalyst, GNI USA, GNI Japan, GNI Hong Kong Limited, Shanghai Genomics Inc. and CPI.
​​
8-K
​​
000-51173
​​
August 31, 2023
​​
  3.1
2.6
​​
Contingent Value Rights Agreement, dated as of December 26, 2022, between Catalyst and American Stock Transfer & Trust Company, LLC
​​
S-3
​​
333-273395
​​
July 24, 2023
​​
2.7
​​
Amendment to Contingent Value Rights Agreement, dated as of March 29, 2023, executed by Catalyst.
​​
8-K
​​
000-51173
​​
March 30, 2023
​​
3.1
​​
Fourth Amended and Restated Certificate of Incorporation of the Company (incorporatedRegistrant
​​
S-8
​​
333-133881
​​
May 8, 2006
​​
II-2

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​​
​​
Incorporated by reference to Exhibit 4.1 to the Company’s FormS-8, (RegNo. 333-133881), as filed with the SEC on May 8, 2006)herein
​​
Exhibit 
No.
​​
Description
​​
Form
​​
File No.
​​
Filing Date
​​
Filed
Herewith
3.2
​​
Certificate of Amendment to the Fourth Amended and Restated Certificate of Incorporation of the Company (incorporated by reference to Exhibit 3.1 to the Company’s Current Report on FormRegistrant
​​
8-K as filed with the SEC on
​​
000-51173
​​
August 20, 2015)2015
​​
3.3
  3.3​​
Second Certificate of Amendment to the Fourth Amended and Restated Certificate of Incorporation of the Company (incorporated by reference to Exhibit 3.1 to the Company’s Current Report on FormRegistrant
​​
8-K as filed with the SEC on
​​
000-51173
​​
February 10, 2017)2017
​​
3.4
  3.4​​Bylaws of the Company, as amended (incorporated by reference to Exhibit 3.1 to the Company’s Current Report on Form8-K, as filed with the SEC on March 6, 2015)
  3.5
Certificate of Designation of Preferences, Rights and LimitationsSeries X Convertible Preferred Stock
​​
8-K
​​
000-51173
​​
December 27, 2022
​​
3.5
​​
Certificate of Designation of Series A ConvertibleY Preferred Stock (incorporated by reference to Exhibit 3.5
​​
8-K
​​
000-51173
​​
June 20, 2023
​​
3.6
​​
Certificate of Elimination for Catalyst’s Series Y Preferred Stock.
​​
8-K
​​
000-51173
​​
August 31, 2023
​​
3.7
​​
Amended and Restated Bylaws of the Company’s FormS-1/A (RegNo. 333-216663), as filed with the SEC on April 4, 2017)Registrant
​​
8-K
​​
000-51173
​​
December 27, 2022
​​
5.1
​​
Opinion of Orrick, Herrington & Sutcliffe LLP
​​
S-3/A
​​
333-273395
​​
October 13, 2023
​​
  4.1
23.1
​Form​
Consent of Common Stock Certificate*EisnerAmper LLP
​​
​​
​​
​​
X
23.2
​​
Consent of Ernst & Young Hua Ming LLP
​​
​​
​​
​​
X
  4.2
23.3
​Form​
Consent of Certificate of Designations*

II-2

Orrick, Herrington & Sutcliffe LLP (contained in Exhibit 5.1)

​​
S-3/A
​​
333-273395
​​
October 13, 2023
​​

Exhibit

Number

24.1
​

Description

​
Power of Attorney (contained in the signature page hereto)
​​
S-3
​​
333-273395
​​
July 24, 2023
​​
107
  4.3​​Form of Warrant Agreement (including warrant certificate)*
Filing Fee Table
  4.4​​Form of Unit Agreement (including form of unit certificate)*
S-3
  4.5​​Form of Indenture
333-273395
  5.1​​Opinion of Morrison & Foerster LLP
July 24, 2023
23.1​​Consent of Independent Registered Public Accounting Firm
23.2Consent of Counsel (included inExhibit 5.1)
24.1Powers of Attorney (included as part of the signature pages hereto)
25.1FormT-1 Statement of Eligibility under Trust Indenture Act of 1939 of Debt Trustee (to be filed prior to any issuance of Debt Securities)(1)

*

To be filed by amendment or by a Current Report on Form8-K and incorporated herein by reference.

(1)ITEM 17.

To be filed in accordance with the requirements of Section 305(b)(2) of the Trust Indenture Act of 1939.

Undertakings.

Item 17.

Undertakings

(a)

The undersigned registrant hereby undertakes:

(1)

To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act;

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement,

Provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the SEC by the Registrant pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in this Registration Statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the Registration Statement.

(i)
To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;
(ii)
To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the “Filing Fee Table” filed as an exhibit in the effective registration statement; and
(iii)
To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement; provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference herein in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.
(2)

That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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(3)

To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4)

That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(i) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

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(i)
If the registrant is relying on Rule 430B,
(A)
Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and
(B)

(ii) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5)

That, for the purpose of determining liabilityproviding the information required by Section 10(a) of the Registrant under the Securities Act of 1933 shall be deemed to any purchaserbe part of and included in the initial distributionregistration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference herein into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date;

(ii)
If the registrant is subject to Rule 430C, each prospectus filed pursuant to Rule 424(b) as part of a registration statement relating to an offering, other than registration statements relying on Rule 430B or other than prospectuses filed in reliance on Rule 430A, shall be deemed to be part of and included in the registration statement as of the date it is first used after effectiveness. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference herein into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such first use, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such date of first use.
(5)
The undersigned Registrantregistrant hereby undertakes that, in a primary offering of securities of the undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used or referred to by the undersigned Registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.

(6)

That, for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant’sregistrant’s annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act)Act of 1934) that is incorporated by reference herein in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(7)(6)

That, insofarInsofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrantregistrant pursuant to the foregoing provisions, or otherwise, the Registrantregistrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrantregistrant of expenses incurred or paid by a director, officer or controlling person of the Registrantregistrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrantregistrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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(8)(7)

To file an application forThe undersigned registrant hereby undertakes that: in a registration statement permitted by Rule 430A,

(i)
For purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the Registrant pursuant to Rule 424(b) (1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective; and
(ii)
For the purpose of determining any liability under the eligibilitySecurities Act of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the trusteesecurities offered therein, and the offering of such securities at that time shall be deemed to act under subsection (a) of Section 310 ofbe the Trust Indenture Act in accordance with the rules and regulations prescribed by the SEC under Section 305(b)(2) of the Trust Indenture Act.

initial bona fide offering thereof.
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SIGNATURES

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the RegistrantCatalyst Biosciences, Inc. certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on FormS-3 and has duly caused this Registration Statement on Form S-3 to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of South San Francisco, State of California, on the 21st24th day of December, 2018.

October, 2023.
​​
Catalyst Biosciences, Inc.
​​
​​
​​
By:
​

​

By:
​​
/s/ Nassim Usman, Ph.D.

​​
​​
​​
Nassim Usman, Ph.D.
​​
​​
​​
President and Chief Executive Officer
​​

SIGNATURES AND POWER OF ATTORNEY

Each person whose signature appears below constitutes and appoints Nassim Usman and Fletcher Payne, and each of them severally, as his true and lawfulattorney-in-fact and agent, each acting alone with full power of substitution and resubstitution, for him and in his name, place and stead, in any and all capacities, to sign this Registration Statement on FormS-3 to be filed in connection with the offering of securities of Catalyst Biosciences, Inc., and any and all amendments (including post-effective amendments) to this registration statement, and any subsequent registration statement filed pursuant to Rule 462 under the Securities Act of 1933, as amended, and to file the same with exhibits thereto, and the other documents in connection therewith, with the Securities and Exchange Commission, granting unto saidattorney-in-fact and agent, each acting alone, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as they might or could do in person, hereby ratifying and confirming all that saidattorney-in-fact or his substitutes, each acting alone, may lawfully do or cause to be done by virtue thereof.

IN WITNESS WHEREOF, each of the undersigned has executed this Power of Attorney as of the date indicated.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and as of the dates indicated.

Signature
​​
Title
​​
Date

Signature

​

Title

​

Date

​		​

/S/ NASSIM USMAN, PH.D.

s/ Nassim Usman, Ph.D.

​​
President and Chief Executive Officer, and Director (Principal
(Principal Executive Officer)
​December 21, 2018​
October 24, 2023
Nassim Usman, Ph.D.
​

/S/ FLETCHER PAYNE

Fletcher Payne

​​
​​
*
​​
Interim Chief Financial Officer (Principal
(Interim Principal Financial Officer and
Principal Accounting Officer)
​December 21, 2018​
October 24, 2023
Seline Miller
​

/S/ ERROL B. DE SOUZA, PH.D.

Errol B. De Souza, Ph.D.

​Director​
December 21, 2018​​
*
​​
Chairman of the Board
​​
October 24, 2023

/S/ JEFF HIMAWAN, PH.D.

Jeff Himawan,

Ying Luo, Ph.D.

DirectorDecember 21, 2018​
​​
​​

/S/ AUGUSTINE LAWLOR

Augustine Lawlor

*
​Director​
Director
December 21, 2018​​
October 24, 2023
Augustine Lawlor
​

/S/ JOHN P. RICHARD

John P. Richard

​Director​
December 21, 2018​​
*
​​
Director
​​
October 24, 2023

/S/ STEPHEN A. HILL, M.D.

Stephen A. Hill, M.D.

Thomas Eastling
DirectorDecember 21, 2018​
​​
​​

/S/ ANDREA S. HUNT

Andrea S. Hunt

*
​Director​
Director
December 21, 2018​​
October 24, 2023
Andrea Hunt
​
*By:
​​
/s/ Nassim Usman, Ph.D.
​​

/S/ EDWARD WILLIAMS

Edward Williams

​Director​
Nassim Usman, Ph.D.
December 21, 2018​​
​​
Attorney-in-Fact
​​

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