As filed with the Securities and Exchange Commission on July 6, 2020

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

CATALYST BIOSCIENCES, INC.

(Exact Name of Registrant as Specified in Its Charter)

611 Gateway Blvd. Suite 710

South San Francisco, California 94080

(Address of Principal Executive Offices) (Zip Code)

Catalyst Biosciences, Inc. 2018 Omnibus Incentive Plan

Catalyst Biosciences, Inc. 2018 Employee Stock Purchase Plan

Inducement Stock Option Award

(Full Title of the Plans)

Nassim Usman, Ph.D.

President and Chief Executive Officer

Catalyst Biosciences, Inc.

611 Gateway Boulevard, Suite 710

South San Francisco, CA 94080

(Name and Address of Agent for Service)

(650) 871-0761

(Telephone Number, including area code, of agent for service)

Copies to:

Clinton Musil

Chief Financial Officer

Catalyst Biosciences, Inc.

611 Gateway Boulevard, Suite 710

South San Francisco, CA 94080

(650) 871-0761

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

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

PART I

INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

Item 1. Plan Information.

Information required by this Item 1 to be contained in the Section 10(a) prospectus is omitted from this registration statement on Form S-8 (the “Registration Statement”) in accordance with Rule 428 under the Securities Act of 1933, as amended (the “Securities Act”) and the instructions to Form S-8. In accordance with the rules and regulations of the Securities and Exchange Commission (the “Commission”) and the instructions to Form S-8, such documents are not being filed with the Commission either as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424 under the Securities Act.

Item 2. Registrant Information and Employee Plan Annual Information.

Information required by this Item 2 to be contained in the Section 10(a) prospectus is omitted from this Registration Statement in accordance with Rule 428 under the Securities Act and the instructions to Form S-8. In accordance with the rules and regulations of the Commission and the instructions to Form S-8, such documents are not being filed with the Commission either as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424 under the Securities Act.

PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference.

The following documents filed by Catalyst Biosciences, Inc. (the “Registrant”) with the Commission pursuant to the Securities Exchange Act of 1934, as amended (the “Exchange Act”), are incorporated herein by reference:

All documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-effective amendment, which indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part hereof from the date of the filing of such documents, except as to specific sections of such statements as set forth therein.

Unless expressly incorporated into this Registration Statement, a report furnished on Form 8-K prior or subsequent to the date hereof shall not be incorporated by reference into this Registration Statement, except as to specific sections of such statements as set forth therein. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained in any subsequently filed document, which also is deemed to be incorporated by reference herein, modifies or supersedes such statement.

Item 4. Description of Securities.

Not applicable.

Item 5. Interests of Named Experts and Counsel.

Not applicable.

Item 6. Indemnification of Directors and Officers.

The Registrant’s restated certificate of incorporation provides that the Registrant’s directors shall not be personally liable to the Registrant or its 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 the Registrant or its 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 Delaware General Corporation Law (“DGCL”), or for any transaction from which the director derived an improper personal benefit. Under the DGCL, the Registrant’s directors have a fiduciary duty to the Registrant 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 of non-monetary relief will remain available. This provision also does not affect the Registrant’s directors’ responsibilities under any other laws, such as federal securities laws or state or federal environmental laws.

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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 Registrant’s restated certificate of incorporation provides that, to the fullest extent permitted by Section 145 of the DGCL, the Registrant shall indemnify any person who is or was a director or officer of the Registrant, or is or was serving at the Registrant’s 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. The Registrant’s bylaws provide that the Registrant 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 the Registrant or is or was serving at the Registrant’s 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, the Registrant has entered into indemnification agreements with each of its directors and executive officers. Pursuant to the indemnification agreements, the Registrant 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 Registrant. The agreements also provide for the advancement of expenses to the directors and officers subject to specified conditions. There are certain exceptions to the Registrant’s 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 the Registrant’s best 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 she initiates.

Section 145 of the DGCL also empowers a corporation to purchase insurance for its officers and directors for such liabilities. The Registrant maintains liability insurance for its officers and directors.

Item 7. Exemption from Registration Claimed.

Not applicable.

Item 8. Exhibits

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Item 9. Undertakings.

Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) above do not apply if the information required to be included in a post-effective amendment by such 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 Exchange Act that are incorporated by reference in the Registration Statement.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the South San Francisco, State of California, on July 6, 2020.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that the undersigned officers and directors of Catalyst Biosciences, Inc., a Delaware corporation, do hereby constitute and appoint Nassim Usman, Ph.D. and Clinton Musil, and each of them, the lawful attorneys-in-fact and agents with full power and authority to do any and all acts and things and to execute any and all instruments which said attorneys and agents, and any one of them, determine may be necessary or advisable or required to enable said corporation to comply with the Securities Act of 1933, as amended, and any rules or regulations or requirements of the Securities and Exchange Commission in connection with this Registration Statement. Without limiting the generality of the foregoing power and authority, the powers granted include the power and authority to sign the names of the undersigned officers and directors in the capacities indicated below to this Registration Statement, to any and all amendments, both pre-effective and post-effective, and supplements to this Registration Statement, and to any and all instruments or documents filed as part of or in conjunction with this Registration Statement or amendments or supplements thereof, and each of the undersigned hereby ratifies and confirms that all said attorneys and agents, or any one of them, shall do or cause to be done by virtue hereof.

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Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following persons on behalf of the Registrant in the capacities and on the dates indicated.

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Exhibit 5.1

Catalyst Biosciences, Inc.

611 Gateway Boulevard, Suite 710

South San Francisco, California 94080

Re:         Registration Statement on Form S-8

Ladies and Gentlemen:

We have acted as counsel for Catalyst Biosciences, Inc., a Delaware corporation (the “Company”), in connection with the preparation and filing with the Securities and Exchange Commission (the “Commission”) of the Company’s registration statement on Form S-8 (the “Registration Statement”) under the Securities Act of 1933, as amended (the “Securities Act”) relating to the registration of (i) 1,300,000 shares of the Company’s common stock (“Shares”), par value $0.001 per share, reserved for issuance pursuant to the Company’s 2018 Omnibus Incentive Plan, as amended, (ii) 239,545 Shares reserved for issuance pursuant to the Company’s Employee Stock Purchase Plan, and (iii) 140,000 Shares reserved for issuance pursuant to an inducement stock option award ((i), (ii) and (iii), collectively, the “Plans”). As your legal counsel, we have reviewed the actions proposed to be taken by you in connection with the issuance and sale of the Shares to be issued under the Plans.

In connection with this opinion, we have examined originals or copies, certified or otherwise identified to our satisfaction, of (i) the Fourth Amended and Restated Certificate of Incorporation of the Company, as amended, (ii) the Bylaws of the Company, as amended, (iii) the Registration Statement, (iv) the Plans and (v) such corporate records, agreements, documents and other instruments, and such certificates or comparable documents of public officials and of officers and representatives of the Company, and have made such inquiries of such officers and representatives, as we have deemed relevant and necessary or appropriate as a basis for the opinion set forth below.

In our examination, we have assumed the legal capacity of all natural persons, the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as facsimile, electronic, certified or photostatic copies, and the authenticity of the originals of such copies. In making our examination of documents executed or to be executed, we have assumed that the parties thereto, other than the Company, had or will have the power, corporate or other, to enter into and perform all obligations thereunder and have also assumed the due authorization by all requisite action, corporate or other, and the execution and delivery by such parties of such documents and the validity and binding effect thereof on such parties. As to any facts material to the opinions expressed herein that we did not independently establish or verify, we have relied upon statements and representations of officers and other representatives of the Company and others and of public officials.

Based on the foregoing and subject to the limitations, qualifications and assumptions set forth herein, we are of the opinion that the Shares to be issued pursuant to the terms of the Plans have been duly authorized and, when issued, delivered and paid for in accordance with the terms of the Plans, will be validly issued, fully paid and non-assessable.

The opinion expressed herein is limited to the corporate laws of the State of Delaware and the federal laws of the United States of America, and we express no opinion as to the effect on the matters covered by this letter of the laws of any other jurisdictions.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement. In giving such consent, we do not hereby admit that we are included in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission promulgated thereunder.

Very truly yours,

/s/ Orrick, Herrington & Sutcliffe LLP

ORRICK, HERRINGTON & SUTCLIFFE LLP

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement of Catalyst Biosciences, Inc. on Form S-8 to be filed on or about July 6, 2020 of our reports dated February 20, 2020, on our audits of the consolidated financial statements as of December 31, 2019 and 2018 and for each of the years then ended, and the effectiveness of Catalyst Biosciences, Inc.’s internal control over financial reporting as of December 31, 2019, which reports were included in the Annual Report on Form 10-K filed February 20, 2020.    Our report includes an explanatory paragraph that refers to a change in the method of accounting for leases due to the adoption of Accounting Standards Update No. 2016-02, Leases (Topic 842).

/s/ EisnerAmper LLP

EISNERAMPER LLP

Iselin, New Jersey

July 6, 2020

Exhibit 99.3

CATALYST BIOSCIENCES INC.

NOTICE OF INDUCEMENT STOCK OPTION AWARD

You (the “Grantee”) have been granted an option to purchase shares of Common Stock (the “Option”), outside of the Catalyst Biosciences, Inc. 2018 Omnibus Incentive Plan, as amended from time to time (the “Plan”), pursuant to Rule 5635(c)(4) of the Nasdaq Listing Rules in connection with the Grantee’s commencement of service as the Company’s Chief Financial Officer. Nevertheless, this Option is subject to the terms and conditions set forth in the Plan as well in this Notice of Inducement Stock Option Award (the “Notice”) and the Inducement Stock Option Award Agreement (the “Option Agreement”) attached hereto, as follows. Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Notice, except to the extent defined in that certain employment agreement by and between the Company and Clinton Musil dated                     , 2020 (the “Employment Agreement”).

Vesting Schedule:

Subject to the Grantee’s Continuous Service through each vesting date and the other limitations set forth in this Notice, the Plan and the Option Agreement, the Option may be exercised, in whole or in part, in accordance with the following schedule (the “Vesting Schedule”): 25% vesting on the one- year anniversary of July 1, 2020, and 1/48 vesting monthly thereafter.

Notwithstanding anything in this Notice, the Plan or the Option Agreement to the contrary, upon the termination of Grantee’s employment without Cause by the Company or as a result of Grantee’s Constructive Termination (each, as such term is defined in the Employment Agreement), this Option shall become vested and exercisable in accordance with the terms of the Employment Agreement.

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During any authorized leave of absence, the vesting of the Option as provided in this schedule shall be suspended after the leave of absence exceeds a period of three (3) months. Vesting of the Option shall resume upon the Grantee’s termination of the leave of absence and return to service to the Company or a Related Entity. The Vesting Schedule of the Option shall be extended by the length of the suspension.

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IN WITNESS WHEREOF, the Company and the Grantee have executed this Notice and agree that the Option is to be governed by the terms and conditions of this Notice, the Plan, and the Option Agreement.

THE GRANTEE ACKNOWLEDGES AND AGREES THAT THE SHARES SUBJECT TO THE OPTION SHALL VEST, IF AT ALL, ONLY DURING THE PERIOD OF THE GRANTEE’S CONTINUOUS SERVICE (NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED THE OPTION OR ACQUIRING SHARES HEREUNDER). THE GRANTEE FURTHER ACKNOWLEDGES AND AGREES THAT NOTHING IN THIS NOTICE, THE OPTION AGREEMENT, OR THE PLAN SHALL CONFER UPON THE GRANTEE ANY RIGHT WITH RESPECT TO FUTURE AWARDS OR CONTINUATION OF THE GRANTEE’S CONTINUOUS SERVICE, NOR SHALL IT INTERFERE IN ANY WAY WITH THE GRANTEE’S RIGHT OR THE RIGHT OF THE COMPANY OR RELATED ENTITY TO WHICH THE GRANTEE PROVIDES SERVICES TO TERMINATE THE GRANTEE’S CONTINUOUS SERVICE, WITH OR WITHOUT CAUSE, AND WITH OR WITHOUT NOTICE. THE GRANTEE ACKNOWLEDGES THAT UNLESS THE GRANTEE HAS A WRITTEN EMPLOYMENT AGREEMENT WITH THE COMPANY TO THE CONTRARY, THE GRANTEE’S STATUS IS AT WILL.

By clicking “Accept” on the button below, the Grantee acknowledges receipt of a copy of the Plan and the Option Agreement, and represents that he or she is familiar with the terms and provisions thereof, and hereby accepts the Option subject to all of the terms and provisions hereof and thereof. The Grantee has reviewed this Notice, the Plan, and the Option Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Notice, and fully understands all provisions of this Notice, the Plan and the Option Agreement. The Grantee hereby agrees that all questions of interpretation and administration relating to this Notice, the Plan and the Option Agreement shall be resolved by the Administrator in accordance with Section 13 of the Option Agreement. The Grantee further agrees to the venue selection in accordance with Section 12 of the Option Agreement. The Grantee further agrees to notify the Company upon any change in the residence address indicated in this Notice.

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INDUCEMENT STOCK OPTION AWARD AGREEMENT

1.     Grant of Option. Catalyst Biosciences, Inc., a Delaware corporation (the “Company”), hereby grants to the Grantee (the “Grantee”) named in the Notice of Inducement Stock Option Award (the “Notice”), an option (the “Option”) to purchase the Total Number of Shares of Common Stock subject to the Option (the “Shares”) set forth in the Notice, at the Exercise Price per Share set forth in the Notice (the “Exercise Price”). This Option is being granted outside of the Catalyst Biosciences, Inc. 2018 Omnibus Incentive Plan, as amended from time to time (the “Plan”), pursuant to Rule 5635(c)(4) of the Nasdaq Listing Rules in connection with the Grantee’s commencement of service as the Company’s Chief Financial Officer. Nevertheless, this Option is subject to the terms and conditions set forth in the Plan as well in the Notice and this Inducement Stock Option Award Agreement (the “Option Agreement”). Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Option Agreement, except to the extent defined in that certain employment agreement by and between the Company and Clinton Musil dated                     , 2020 (the “Employment Agreement”).

2.     Exercise of Option.

(a)    Right to Exercise. The Option shall be exercisable during its term in accordance with the Vesting Schedule set out in the Notice and with the applicable provisions of the Plan and this Option Agreement. The Grantee shall be subject to reasonable limitations on the number of requested exercises during any monthly or weekly period as determined by the Administrator. In no event shall the Company issue fractional Shares.

(b)    Method of Exercise. The Option shall be exercisable by delivery of an exercise notice (a form of which is attached as Exhibit A) or by such other procedure as specified from time to time by the Administrator which shall state the election to exercise the Option, the whole number of Shares in respect of which the Option is being exercised, and such other provisions as may be required by the Administrator. The exercise notice shall be delivered in person, by certified mail, or by such other method (including electronic transmission) as determined from time to time by the Administrator to the Company accompanied by payment of the Exercise Price. As a condition to the exercise of the Option, the Grantee must also make arrangements with the Company for payment of any tax withholding obligations.

(c)    Taxes. The Company or any Related Entity shall be entitled, if necessary or desirable, to deduct and withhold (or, in the sole discretion of the Company, secure payment from the Grantee in lieu of withholding) the amount of any tax withholding due with respect to this Option. In the Grantee’s sole discretion, such tax withholding may be accomplished by the withholding of Shares which would otherwise be issued upon Option exercise to the Grantee in an amount whose Fair Market Value equal to the amount required to be withheld (provided the amount withheld does not exceed the maximum statutory tax rate for an employee in the applicable jurisdictions or such lesser amount as is necessary to avoid adverse accounting treatment).

3.    Method of Payment. Payment of the Exercise Price shall be made by any of the following, or a combination thereof, at the election of the Grantee; provided, however, that such exercise method does not then violate any Applicable Law and, provided further, that the portion of the Exercise Price equal to the par value of the Shares must be paid in cash or other legal consideration permitted by the Delaware General Corporation Law:

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(a)    cash;

(b)    check;

(c)    surrender of Shares held for the requisite period, if any, necessary to avoid a charge to the Company’s earnings for financial reporting purposes, or delivery of a properly executed form of attestation of ownership of Shares as the Administrator may require which have a Fair Market Value on the date of surrender or attestation equal to the aggregate Exercise Price of the Shares as to which the Option is being exercised;

(d)    payment through a “net exercise” such that, without the payment of any funds, the Grantee may exercise the Option and receive the net number of Shares equal to (i) the number of Shares as to which the Option is being exercised, multiplied by (ii) a fraction, the numerator of which is the Fair Market Value per Share (on such date as is determined by the Administrator) less the Exercise Price per Share, and the denominator of which is such Fair Market Value per Share (the number of net Shares to be received shall be rounded down to the nearest whole number of Shares); or

(e)    while the Common Stock is listed on a national stock exchange or a national market system, payment through a broker-dealer sale and remittance procedure pursuant to which the Grantee (i) shall provide written instructions to a Company-designated brokerage firm to effect the immediate sale of some or all of the purchased Shares and remit to the Company sufficient funds to cover the aggregate exercise price payable for the purchased Shares and (ii) shall provide written directives to the Company to deliver the certificates for the purchased Shares directly to such brokerage firm in order to complete the sale transaction.

4.     Restrictions on Exercise. The Option may not be exercised if the issuance of the Shares subject to the Option upon such exercise would constitute a violation of any Applicable Laws. If the exercise of the Option within the applicable time periods set forth in Section 5, 6 and 7 of this Option Agreement is prevented by the provisions of this Section 4, the Option shall remain exercisable until one (1) month after the date the Grantee is notified by the Company that the Option is exercisable, but in any event no later than the Expiration Date set forth in the Notice.

5.     Termination or Change of Continuous Service. In the event the Grantee’s Continuous Service terminates, the Grantee may, but only during the Post-Termination Exercise Period, exercise the portion of the Option that was vested at the date of such termination (the “Termination Date”), including but not limited to, any portion which vests due to the termination of Grantee’s employment without Cause by the Company or as a result of Grantee’s Constructive Termination (each, as such term is defined in the Employment Agreement). The Post-Termination Exercise Period shall commence on the Termination Date. In no event, however, shall the Option be exercised later than the Expiration Date set forth in the Notice. In the event of the Grantee’s change in status from Employee, Director or Consultant to any other status of Employee, Director or Consultant, the Option shall remain in effect and the Option shall continue to vest in accordance with the Vesting Schedule set forth in the Notice. Except as provided in Sections 6 and 7 below, to the extent that the Option was unvested on the Termination Date, or if the Grantee does not exercise the vested portion of the Option within the Post-Termination Exercise Period, the Option shall terminate.

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6.     Disability of Grantee. In the event the Grantee’s Continuous Service terminates as a result of his or her Disability, the Grantee may, but only within twelve (12) months commencing on the Termination Date (but in no event later than the Expiration Date), exercise the portion of the Option that was vested on the Termination Date. To the extent that the Option was unvested on the Termination Date, or if the Grantee does not exercise the vested portion of the Option within the time specified herein, the Option shall terminate.

7.     Death of Grantee. In the event of the termination of the Grantee’s Continuous Service as a result of his or her death, or in the event of the Grantee’s death during the Post-Termination Exercise Period, the person who acquired the right to exercise the Option pursuant to Section 8 may exercise the portion of the Option that was vested at the date of termination within twelve (12) months commencing on the date of death (but in no event later than the Expiration Date). To the extent that the Option was unvested on the date of death, or if the vested portion of the Option is not exercised within the time specified herein, the Option shall terminate.

8.     Transferability of Option. The Option may not be transferred in any manner other than by will or by the laws of descent and distribution; provided, however, that the Option may be transferred during the lifetime of the Grantee to the extent and in the manner authorized by the Administrator. Notwithstanding the foregoing, the Grantee may designate one or more beneficiaries of the Grantee’s Option in the event of the Grantee’s death on a beneficiary designation form provided by the Administrator. Following the death of the Grantee, the Option, to the extent provided in Section 7, may be exercised (a) by the person or persons designated under the deceased Grantee’s beneficiary designation or (b) in the absence of an effectively designated beneficiary, by the Grantee’s legal representative or by any person empowered to do so under the deceased Grantee’s will or under the then applicable laws of descent and distribution. The terms of the Option shall be binding upon the executors, administrators, heirs, successors and transferees of the Grantee.

9.     Term of Option. The Option must be exercised no later than the Expiration Date set forth in the Notice or such earlier date as otherwise provided herein. After the Expiration Date or such earlier date, the Option shall be of no further force or effect and may not be exercised.

10.    Tax Consequences. The Grantee may incur tax liability as a result of the Grantee’s purchase or disposition of the Shares. THE GRANTEE SHOULD CONSULT A TAX ADVISER BEFORE EXERCISING THE OPTION OR DISPOSING OF THE SHARES.

11.    Entire Agreement: Governing Law. The Notice, the Plan and this Option Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and the Grantee with respect to the subject matter hereof, and may not be modified adversely to the Grantee’s interest except by means of a writing signed by the Company and the Grantee. Nothing in the Notice, the Plan and this Option Agreement (except as expressly provided therein) is intended to confer any rights or remedies on any persons other than the parties. The Notice, the Plan and this Option Agreement are to be construed in accordance with and governed by the internal laws of the State of Delaware without giving effect to any choice of law rule that would cause the application of the laws of any jurisdiction other than the internal laws of the State of Delaware to the rights and duties of the parties. Should any provision of the Notice, the Plan or this Option Agreement be determined to be illegal or unenforceable, such provision shall be enforced to the fullest extent allowed by law and the other provisions shall nevertheless remain effective and shall remain enforceable.

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12.   Venue and Jurisdiction. The parties agree that any suit, action, or proceeding arising out of or relating to the Notice, the Plan or this Option Agreement shall be brought exclusively in the United States District Court for Delaware (or should such court lack jurisdiction to hear such action, suit or proceeding, in a Delaware state court) and that the parties shall submit to the jurisdiction of such court. The parties irrevocably waive, to the fullest extent permitted by law, any objection the party may have to the laying of venue for any such suit, action or proceeding brought in such court. If any one or more provisions of this Section 12 shall for any reason be held invalid or unenforceable, it is the specific intent of the parties that such provisions shall be modified to the minimum extent necessary to make it or its application valid and enforceable.

13.   Construction. The captions used in the Notice and this Option Agreement are inserted for convenience and shall not be deemed a part of the Option for construction or interpretation. Except when otherwise indicated by the context, the singular shall include the plural and the plural shall include the singular. Use of the term “or” is not intended to be exclusive, unless the context clearly requires otherwise.

14.   Administration and Interpretation. Any question or dispute regarding the administration or interpretation of the Notice, the Plan or this Option Agreement shall be submitted by the Grantee or by the Company to the Administrator. The resolution of such question or dispute by the Administrator shall be final and binding on all persons.

15.   Notices. Any notice required or permitted hereunder shall be given in writing and shall be deemed effectively given upon personal delivery, upon deposit for delivery by an internationally recognized express mail courier service or upon deposit in the United States mail by certified mail (if the parties are within the United States), with postage and fees prepaid, addressed to the other party at its address as shown in these instruments, or to such other address as such party may designate in writing from time to time to the other party.

END OF AGREEMENT

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EXHIBIT A

INDUCEMENT STOCK OPTION EXERCISE NOTICE

Catalyst Biosciences, Inc.

611 Gateway Boulevard, Suite 710

South San Francisco, CA 94080

Attention: Secretary

1.    Exercise of Option. Effective as of today, [DATE], the undersigned (the “Grantee”) hereby elects to exercise the Grantee’s option to purchase shares of the Common Stock (the “Shares”) of Catalyst Biosciences, Inc. (the “Company”) granted outside of but subject to the terms and conditions of the Company’s 2018 Omnibus Incentive Plan, as amended from time to time (the “Plan”) and the Inducement Stock Option Award Agreement (the “Option Agreement”) and Notice of Inducement Stock Option Award (the “Notice”) dated July 1, 2020 and this Exercise Notice (the “Exercise Notice”). Unless otherwise defined herein, the terms defined in the Plan shall have the same defined meanings in this Exercise Notice.

2.    Representations of the Grantee. The Grantee acknowledges that the Grantee has received, read and understood the Notice, the Plan and the Option Agreement and agrees to abide by and be bound by their terms and conditions.

3.    Rights as Stockholder. Until the stock certificate evidencing such Shares is issued (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company), no right to vote or receive dividends or any other rights as a stockholder shall exist with respect to the Shares, notwithstanding the exercise of the Option. The Company shall issue (or cause to be issued) such stock certificate promptly after the Option is exercised. No adjustment will be made for a dividend or other right for which the record date is prior to the date the stock certificate is issued, except as provided in Section 10 of the Plan.

4.    Delivery of Payment. The Grantee herewith delivers to the Company the full Exercise Price for the Shares, which, to the extent selected, shall be deemed to be satisfied by use of the broker-dealer sale and remittance procedure to pay the Exercise Price provided in Section 3(e) of the Option Agreement.

5.    Tax Consultation. The Grantee understands that the Grantee may suffer adverse tax consequences as a result of the Grantee’s purchase or disposition of the Shares. The Grantee represents that the Grantee has consulted with any tax consultants the Grantee deems advisable in connection with the purchase or disposition of the Shares and that the Grantee is not relying on the Company for any tax advice.

6.    Taxes. The Grantee agrees to satisfy all applicable foreign, federal, state and local income and employment tax withholding obligations and herewith delivers to the Company the full amount of such obligations or has made arrangements acceptable to the Company to satisfy such obligations.

7.    Successors and Assigns. The Company may assign any of its rights under this Exercise Notice to single or multiple assignees, and this Exercise Notice shall inure to the benefit of the successors and assigns of the Company. This Exercise Notice shall be binding upon the Grantee and his or her heirs, executors, administrators, successors and assigns.

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8.    Construction. The captions used in this Exercise Notice are inserted for convenience and shall not be deemed a part of this Exercise Notice for construction or interpretation. Except when otherwise indicated by the context, the singular shall include the plural and the plural shall include the singular. Use of the term “or” is not intended to be exclusive, unless the context clearly requires otherwise.

9.    Administration and Interpretation. The Grantee hereby agrees that any question or dispute regarding the administration or interpretation of this Exercise Notice shall be submitted by the Grantee or by the Company to the Administrator. The resolution of such question or dispute by the Administrator shall be final and binding on all persons.

10.    Governing Law; Severability. This Exercise Notice is to be construed in accordance with and governed by the internal laws of the State of Delaware without giving effect to any choice of law rule that would cause the application of the laws of any jurisdiction other than the internal laws of the State of Delaware to the rights and duties of the parties. Should any provision of this Exercise Notice be determined by a court of law to be illegal or unenforceable, such provision shall be enforced to the fullest extent allowed by law and the other provisions shall nevertheless remain effective and shall remain enforceable.

11.    Notices. Any notice required or permitted hereunder shall be given in writing and shall be deemed effectively given upon personal delivery, upon deposit for delivery by an internationally recognized express mail courier service or upon deposit in the United States mail by certified mail (if the parties are within the United States), with postage and fees prepaid, addressed to the other party at its address as shown below beneath its signature, or to such other address as such party may designate in writing from time to time to the other party.

12.    Further Instruments. The parties agree to execute such further instruments and to take such further action as may be reasonably necessary to carry out the purposes and intent of this agreement.

13.    Entire Agreement. The Notice, the Plan and the Option Agreement are incorporated herein by reference and together with this Exercise Notice constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and the Grantee with respect to the subject matter hereof, and may not be modified adversely to the Grantee’s interest except by means of a writing signed by the Company and the Grantee. Nothing in the Notice, the Plan, the Option Agreement and this Exercise Notice (except as expressly provided therein) is intended to confer any rights or remedies on any persons other than the parties.

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