# EDGAR Filing Document

**Accession Number:** 0001953926
**File Stem:** 0001104659-25-076498
**Filing Date:** 2025-8
**Character Count:** 40299
**Document Hash:** e2d5c45c538abca68ca217e05321c480
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-076498.hdr.sgml**: 20250812

**ACCESSION NUMBER**: 0001104659-25-076498

**CONFORMED SUBMISSION TYPE**: S-8

**PUBLIC DOCUMENT COUNT**: 16

**FILED AS OF DATE**: 20250812

**DATE AS OF CHANGE**: 20250812

**EFFECTIVENESS DATE**: 20250812

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Zenas BioPharma, Inc.
- **CENTRAL INDEX KEY:** 0001953926
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** S-8
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 333-289510
- **FILM NUMBER:** 251204111

**BUSINESS ADDRESS:**
- **STREET 1:** 852 WINTER STREET, SUITE 250
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02451
- **BUSINESS PHONE:** 857-271-2954

**MAIL ADDRESS:**
- **STREET 1:** 852 WINTER STREET, SUITE 250
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02451

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Zenas BioPharma (Cayman) Ltd
- **DATE OF NAME CHANGE:** 20221108

**As filed with the Securities and Exchange Commission on August 12, 2025**

**Registration No. 333-**

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**WASHINGTON, DC 20549**

**FORM S-8**

**REGISTRATION STATEMENT**

***UNDER***

***THE SECURITIES ACT OF 1933***

**ZENAS BIOPHARMA, INC.**

**(Exact name of registrant as specified in its charter)**

---

| | |
|:---|:---|
| **Delaware** | **93-2749244** |
| **(State or other jurisdiction of**<br> **incorporation or organization)** | **(I.R.S. Employer**<br> **Identification No.)** |
| **852 Winter Street, Suite 250**<br> **Waltham, MA**  | **02451** |
| **(Address of Principal Executive Offices)** | **(Zip Code)** |

---

**Inducement Option Award Agreements**

**(Full titles of the plans)**

**Leon O. Moulder, Jr.**

**Chief Executive Officer**

**Zenas BioPharma, Inc.**

**852 Winter Street, Suite 250**

**Waltham, MA 02451**

**(Name and address of agent for service)**

**(857) 271-2954**

**(Telephone number, including area code, of agent for service)**

***Please send a copy of all communications to:***

**Thomas Danielski**

**Nicholas Roper**

**Ropes & Gray LLP**

**Prudential Tower**

**800 Boylston Street**

**Boston, MA 02199-3600**

**617-951-7000**

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 the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer ◻ Accelerated filer ◻ <br> Non-accelerated filer ⌧ Smaller reporting company ⌧ <br> 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. ◻

**EXPLANATORY NOTE**

Zenas BioPharma, Inc. (the "Registrant") is filing this Registration Statement on Form S-8 with the Securities and Exchange Commission (the "Commission") for the purpose of registering an aggregate of 762,000 shares of its common stock, par value $0.0001 per share ("Common Stock") issuable upon the vesting, exercise and settlement of certain stock option grants by the Registrant to three employees of the Registrant, in each case in reliance on and pursuant to the employment inducement exemption under Rule 5635(c)(4) of The Nasdaq Stock Market Rules.

**PART I**

As permitted by Rule 428(a) under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement omits the information specified in Part I of Form S-8. The documents containing the information specified in Part I will be delivered to the employees to whom stock options were issued. These documents, and the documents incorporated by reference in this Registration Statement pursuant to Item 3 of Part II of this Form S-8, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the Securities Act.

**PART II**

**INFORMATION REQUIRED IN THE REGISTRATION STATEMENT**

**Item 3. Incorporation of Documents by Reference.**

The following documents, which have been filed by the Registrant with the Commission, are incorporated herein by reference:

[a.](https://www.sec.gov/ix?doc=/Archives/edgar/data/1953926/000155837025002631/zbio-20241231x10k.htm) [the Registrant's Annual Report on Form 10-K for the fiscal year ended December 31, 2024, filed on March 11, 2025;](https://www.sec.gov/ix?doc=/Archives/edgar/data/1953926/000155837025002631/zbio-20241231x10k.htm)

&nbsp;&nbsp;&nbsp;&nbsp;b. the Registrant's Quarterly Reports on Form 10-Q for the fiscal quarter ended March 31, 2025, filed on [May 15, 2025](https://www.sec.gov/ix?doc=/Archives/edgar/data/1953926/000155837025007803/zbio-20250331x10q.htm) and for the fiscal quarter ended June 30, 2025, filed on [August 12, 2025](https://www.sec.gov/Archives/edgar/data/1953926/000155837025011147/zbio-20250630x10q.htm) ;

[c.](https://www.sec.gov/ix?doc=/Archives/edgar/data/1953926/000110465925058892/tm2517793d1_8k.htm) [the Current Report on Form 8-K filed on June 12, 2025 (except for portions of such reports which were furnished and not filed);](https://www.sec.gov/ix?doc=/Archives/edgar/data/1953926/000110465925058892/tm2517793d1_8k.htm)

&nbsp;&nbsp;&nbsp;&nbsp;d. the information specifically incorporated by reference into the Registrant's [Annual Report on Form 10-K for the fiscal year ended December 31, 2024](https://www.sec.gov/ix?doc=/Archives/edgar/data/1953926/000155837025002631/zbio-20241231x10k.htm) from the Registrant's [Definitive Proxy Statement on Schedule 14A for the 2025 Annual Meeting of Stockholders, filed on April 28, 2025](https://www.sec.gov/ix?doc=/Archives/edgar/data/1953926/000110465925039765/tm2512976-3_def14a.htm) ; and

&nbsp;&nbsp;&nbsp;&nbsp;e. the description of the Registrant's Common Stock which is contained in [Exhibit 4.3](https://www.sec.gov/Archives/edgar/data/1953926/000155837025002631/zbio-20241231xex4d3.htm) to the Registrant's Annual Report
on Form 10-K for the fiscal year ended December 31, 2024, filed on March 11, 2025, including any amendments or reports
filed for the purpose of updating such description.

All reports and other documents filed by the Registrant after the date hereof pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act (other than Current Reports on Form 8-K furnished pursuant to Item 2.02 or Item 7.01 of Form 8-K, including any exhibits included with such information that are related to such items) prior to the filing of a post-effective amendment to this Registration Statement that indicates that all securities offered hereby have been sold or which deregisters all securities then remaining unsold shall be deemed to be incorporated herein by reference herein and to be part hereof from the date of filing of such reports and documents. Any statement contained herein or 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 herein or in any subsequently filed report or document which also is incorporated or is deemed to be incorporated by reference herein modifies or supersedes such earlier statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration 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.**

As permitted by Section 102(b)(7) of the DGCL, our restated certificate of incorporation (our "Restated Charter") includes a provision to eliminate the personal liability of our directors and officers for monetary damages for breach of their fiduciary duties as directors, subject to certain exceptions. In addition, our Restated Charter and amended and restated bylaws provide that we are required to indemnify our officers and directors under certain circumstances, including those circumstances in which indemnification would otherwise be discretionary, and we are required to advance expenses to our officers and directors as incurred in connection with proceedings against them for which they may be indemnified, in each case except to the extent that the DGCL prohibits the elimination or limitation of liability of directors or officers for breaches of fiduciary duty.

Section 145(a) of the DGCL provides that a corporation shall have the power to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by him in connection with such action, suit or proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interest of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful. The termination of any action, suit or proceeding by judgment, order, settlement, conviction or upon a plea of nolo contendere or its equivalent shall not, of itself, create a presumption that the person did not act in good faith and in a manner which the person 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 reasonable cause to believe that his conduct was unlawful.

Section 145(b) of the DGCL provides that a corporation shall have the power to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against expenses (including attorneys' fees) actually and reasonably incurred by him in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation and except that no indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper.

We have entered into indemnification agreements with our directors and with certain of our officers. These indemnification agreements provide broader indemnity rights than those provided under the DGCL and our Restated Charter. These indemnification agreements are not intended to deny or otherwise limit third-party or derivative suits against us or our directors or officers, but to the extent a director or officer were entitled to indemnity or contribution under the indemnification agreement, the financial burden of a third-party suit would be borne by us, and we would not benefit from derivative recoveries against the director or officer. Such recoveries would accrue to our benefit but would be offset by our obligations to the director or officer under the indemnification agreement.

We maintain directors' and officers' liability insurance for the benefit of our directors and officers.

**Item 7. Exemption From Registration Claimed.**

Not applicable.

**Item 8. Exhibits.**

---

| | |
|:---|:---|
| **<u>Exhibit</u>** |  |
| [<u>4.1</u>](https://www.sec.gov/Archives/edgar/data/1953926/000110465924100177/tm2332800d24_ex3-1.htm) | [<u>Restated Certificate of Incorporation (previously filed as Exhibit 3.1 to the Registrant's Current Report on Form 8-K filed with the SEC on September 16, 2024 and incorporated herein by reference).</u>](https://www.sec.gov/Archives/edgar/data/1953926/000110465924100177/tm2332800d24_ex3-1.htm) |
| [<u>4.2</u>](https://www.sec.gov/Archives/edgar/data/1953926/000110465924100177/tm2332800d24_ex3-2.htm) | [<u>Amended and Restated Bylaws (previously filed as Exhibit 3.2 to the Registrant's Current Report on Form 8-K filed with the SEC on September 16, 2024 and incorporated herein by reference).</u>](https://www.sec.gov/Archives/edgar/data/1953926/000110465924100177/tm2332800d24_ex3-2.htm) |
| [<u>4.3\*</u>](tm2522790d1_ex4-3.htm) | [<u>Form of Inducement Option Award Agreement.</u>](tm2522790d1_ex4-3.htm) |
| [<u>4.4</u>](https://www.sec.gov/Archives/edgar/data/1953926/000110465924100244/tm2332800d22_ex4-6.htm) | [<u>Zenas BioPharma, Inc. 2024 Equity Incentive Plan (incorporated by reference to Exhibit 4.6 to the registration statement on Form S-8 filed on September 16, 2024, File No. 333-282151).</u>](https://www.sec.gov/Archives/edgar/data/1953926/000110465924100244/tm2332800d22_ex4-6.htm) |
| [<u>5.1\*</u>](tm2522790d1_ex5-1.htm) | [<u>Opinion of Ropes & Gray LLP</u>](tm2522790d1_ex5-1.htm) |
| [<u>23.1\*</u>](tm2522790d1_ex23-1.htm) | [<u>Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm</u>](tm2522790d1_ex23-1.htm) |
| [<u>23.2\*</u>](tm2522790d1_ex5-1.htm) | [<u>Consent of Ropes & Gray LLP (included in the opinion filed as Exhibit 5.1)</u>](tm2522790d1_ex5-1.htm) |
| [<u>24.1\*</u>](#a_001) | [<u>Powers of Attorney (included on the signature page in Part II)</u>](#a_001) |
| [107\*](tm2522790d1_ex-filingfees.htm) | [Filing Fee Table.](tm2522790d1_ex-filingfees.htm) |

---

\* Filed herewith.

**Item 9. Undertakings.**

(a) The undersigned Registrant hereby undertakes:

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

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

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(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 a prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective Registration Statement;

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(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) and (a)(1)(ii) above shall 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 15(d) of the Exchange Act that are incorporated by reference in the Registration Statement.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2) That, for the purpose of determining any liability under the Securities Act, 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.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(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.

(b) The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the Registrant's annual report pursuant to Section 13(a) or 15(d) of the Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference 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.

(c) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant 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 Registrant 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 and will be governed by the final adjudication of such issue.

**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 City of Waltham, Massachusetts, on this 12th day of August, 2025.

---

| | |
|:---|:---|
| **ZENAS BIOPHARMA, INC.** | **ZENAS BIOPHARMA, INC.** |
| By: | /s/ Leon O. Moulder, Jr. |
|  | Name: Leon O. Moulder, Jr. |
|  | Title: Chief Executive Officer |

---

**POWER OF ATTORNEY**

Each person whose signature appears below constitutes and appoints Leon O. Moulder, Jr. and Joseph Farmer, and each of them singly, his or her true and lawful attorneys-in-fact and agents with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement on Form S-8 to be filed by Zenas BioPharma, Inc. and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, and each of them, or their substitutes, may lawfully do or cause to be done by virtue hereof.

\* \* \* \*

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

---

| | | |
|:---|:---|:---|
| **Signature** | **Title** | **Date** |
| /s/ Leon O. Moulder, Jr.<br> Leon O. Moulder, Jr. | Chief Executive Officer and Director<br> (Principal Executive Officer) | August 12, 2025 |
| /s/ Jennifer Fox<br> Jennifer Fox | Chief Business Officer, Chief Financial Officer and Treasurer<br> (Principal Accounting and Financial Officer) | August 12, 2025 |
| /s/ Patricia Allen<br> Patricia Allen | Director | August 12, 2025 |
| /s/ James Boylan<br> James Boylan | Director | August 12, 2025 |
| <br> Patrick Enright | Director | August 12, 2025 |
| /s/ Tomas Kiselak<br> Tomas Kiselak | Director | August 12, 2025 |
| /s/ Hongbo Lu, Ph.D.<br> Hongbo Lu, Ph.D. | Director | August 12, 2025 |
| /s/ Jake Nunn<br> Jake Nunn | Director | August 12, 2025 |
| /s/ John Orloff, M.D. | Director | August 12, 2025 |
| John Orloff, M.D. |  |  |

---

## Exhibit 4.3

**Exhibit 4.3**

---

| | |
|:---|:---|
| &nbsp;&nbsp;**Name:** | &nbsp;&nbsp;[●] |
| &nbsp;&nbsp;**Number of Shares of Stock subject to the Stock Option:** | &nbsp;&nbsp;[●] |
| &nbsp;&nbsp;**Exercise Price Per Share:** | &nbsp;&nbsp;$[●] |
| &nbsp;&nbsp;**Date of Grant:** | &nbsp;&nbsp;[●] |
| &nbsp;&nbsp;**Vesting Commencement Date:** | &nbsp;&nbsp;[●] |

---

**zenas biopharma, INC.**

**<u>Inducement Option Award Agreement</u>**

This agreement (this "**Agreement**") evidences a stock option (the "**Stock Option**") granted by Zenas BioPharma, Inc., a Delaware corporation (the "**Company**"), to the individual named above (the "**Participant**"), pursuant to an exception to shareholder approval providing for inducement grants under Rule 5635(c)(4) of the Nasdaq Listing Rules as an inducement material to the Participant's entering into employment with the Company within the meaning of Rule 5635(c)(4) of the Nasdaq Listing Rules. The Stock Option shall not be deemed to be granted under the Zenas Biopharma, Inc. 2024 Equity Incentive Plan (the "**<u>Plan</u>**"). Notwithstanding the foregoing, the Stock Option is subject in its entirety to the terms of Plan, the terms of which are hereby incorporated into this Agreement. Except as otherwise defined herein, all capitalized terms used herein have the same meaning as in the Plan.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1. <u>Grant of Stock Option</u>. On the date of grant set forth above (the "**Date of Grant**"), the Company granted to the Participant the Stock Option to purchase, pursuant to and subject to the terms and conditions set forth in this Agreement, up to the number of shares of Stock set forth above (the "**Shares**"), with an exercise price per Share as set forth above, in each case subject to adjustment pursuant to Section 7 of the Plan in respect of transactions occurring after the date hereof.

The Stock Option evidenced by this Agreement is a non-statutory option (that is, an option that is not intended to qualify as an incentive stock option).

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2. <u>Vesting</u>. The term "**vest**" as used herein with respect to the Stock Option or any portion thereof means to become exercisable and the term "**vested**" as used herein with respect to the Stock Option (or any portion thereof) means that the Stock Option (or portion thereof) is then exercisable. Unless earlier terminated, forfeited, relinquished or expired, the Stock Option will vest as follows: [INSERT VESTING SCHEDULE]

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3. <u>Exercise of the Stock Option</u>. No portion of the Stock Option may be exercised until such portion vests. Each election to exercise any vested portion of the Stock Option will be subject to the terms and conditions of this Agreement and must be in written or electronic form acceptable to the Administrator, signed (including by electronic signature) by the Participant or, if at the relevant time the Stock Option has passed to the estate or beneficiary of the Participant or a permitted transferee, by such estate or beneficiary or permitted transferee. Each such written or electronic exercise election must be received by the Company at its principal office or at such other place or by such other party as the Administrator may prescribe and must be accompanied by payment in full of the exercise price by cash or check, or through a broker-assisted exercise program acceptable to the Administrator. Subject to earlier termination as set forth herein or in the Plan (including Section 6(a)(iv) of the Plan), the latest date on which the Stock Option or any portion thereof may be exercised is the tenth (10<sup>th</sup>) anniversary of the Date of Grant and, if not exercised on or prior to such date, the Stock Option or any remaining portion thereof will thereupon immediately terminate.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4. <u>Cessation of Employment</u>. Except as (a) the Administrator may determine in its discretion or (b) expressly provided for in an employment agreement between the Participant and the Company that is in effect at the time of such termination, if the Participant's Employment ceases for any reason, the Stock Option, to the extent not then vested, will be immediately forfeited for no consideration, and any vested portion of the Stock Option that is then outstanding will remain exercisable for the period, if any, described in Section 6(a)(iv) of the Plan.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5. <u>Forfeiture; Recovery of Compensation</u>. By accepting, or being deemed to have accepted, the Stock Option, the Participant expressly acknowledges and agrees that his or her rights, and those of any permitted transferee, with respect to the Stock Option, including the right to any Shares acquired under the Stock Option and any amounts received in respect thereof, are subject to Section 6(a)(v) of the Plan (including any successor provision). The Participant further agrees to be bound by the terms of any applicable clawback or recoupment policy of the Company.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6. <u>Nontransferability</u>. The Stock Option may not be transferred except as expressly permitted under Section 6(a)(iii) of the Plan.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7. <u>Taxes</u>. The Participant expressly acknowledges and agrees that the Participant's rights hereunder, including the right to be issued Shares upon exercise of the Stock Option, are subject to the Participant promptly paying to the Company in cash or by check (or by such other means as may be acceptable to the Administrator in its discretion) all taxes required to be withheld. No Shares will be transferred pursuant to the exercise of this Stock Option unless and until the person exercising the Stock Option has remitted to the Company an amount sufficient to satisfy any federal, state, or local withholding tax requirements, or has made other arrangements reasonably satisfactory to the Company with respect to such taxes. The Participant authorizes the Company and any Subsidiary to withhold such amounts from any amounts otherwise owed to the Participant, but nothing in this sentence will be construed as relieving the Participant from any liability for satisfying his or her obligation under the preceding provisions of this Section.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8. <u>Section 280G</u>. If any payment or benefit that the Participant may receive in respect of the Stock Option (the "<u>Payment</u>"), would (i) constitute a "parachute payment" within the meaning of Section 280G of the Code, and (ii) but for this sentence, be subject to the excise tax imposed by Section 4999 of the Code (the "<u>Excise Tax</u>"), then such Payment shall be reduced to the Reduced Amount. The "<u>Reduced Amount</u>" shall be either (A) the largest portion of the Payment that would result in no portion of the Payment being subject to the Excise Tax or (B) the largest portion, up to and including the total amount, of the Payment, whichever of the amounts determined under (A) and (B), after taking into account all applicable federal, state and local employment taxes, income taxes, and the Excise Tax (all computed at the highest applicable marginal rate), results in the Participant's receipt, on an after-tax basis, of the greater amount of the Payment notwithstanding that all or some portion of the Payment may be subject to the Excise Tax.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9. <u>No Guarantee of Continued Service</u>. The Participant acknowledges and agrees that nothing in this Agreement constitutes an express or implied promise of continued employment or other engagement with the Company or any Subsidiary for any period of time or shall interfere in any way with the right of the Company or any Subsidiary to terminate the Participant's relationship as an employee or other service provider at any time, with or without Cause.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10. <u>Acknowledgements</u>. The Participant acknowledges and agrees that (i) this Agreement may be executed in two or more counterparts, each of which will be an original and all of which together will constitute one and the same instrument, (ii) this Agreement may be executed and exchanged using facsimile, portable document format (PDF) or electronic signature, which, in each case, will constitute an original signature for all purposes hereunder, and (iii) such signature by the Company will be binding against the Company and will create a legally binding agreement when this Agreement is countersigned by the Participant.

*[Signature page follows.]*

The Company, by its duly authorized officer, and the Participant have executed this Agreement.

---

| |
|:---|
| ZENAS BIOPHARMA, INC. |
| By: |
| Name: |
| Title: |

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| | |
|:---|:---|
| Agreed and Accepted: | Agreed and Accepted: |
| By | |
|  | [Participant's Name] |

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*Signature Page to Inducement Option Agreement*

## Exhibit 5.1

**Exhibit 5.1**

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| | |
|:---|:---|
| ![](tm2522790d1_ex5-1img01.jpg) | ROPES & GRAY LLP |
| ![](tm2522790d1_ex5-1img01.jpg) | PRUDENTIAL TOWER |
| ![](tm2522790d1_ex5-1img01.jpg) | 800 BOYLSTON STREET |
| ![](tm2522790d1_ex5-1img01.jpg) | BOSTON, MA 02199-3600 |
| ![](tm2522790d1_ex5-1img01.jpg) | WWW.ROPESGRAY.COM |

---

August 12, 2025

Zenas BioPharma, Inc.

852 Winter Street, Suite 250

Waltham, MA 02451

Ladies and Gentlemen:

This opinion letter is furnished to you in connection with the registration statement on Form S-8 (the "<u>Registration Statement</u>"), filed by Zenas BioPharma, Inc., a Delaware corporation (the "<u>Company</u>"), on the date hereof, with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the "<u>Securities Act</u>"), for the registration of 762,000 shares of Common Stock, $0.0001 par value per share, of the Company (the "<u>Shares</u>"). The Shares are issuable upon the exercise of certain stock options granted by the Company to employees of the Company as an inducement material to entry into employment with the Company (each, an "<u>Inducement Award Agreement</u>" and collectively, the "<u>Inducement Award Agreements</u>").

We are familiar with the actions taken by the Company in connection with the adoption of the Inducement Award Agreements. We have examined such certificates, documents and records and have made such investigation of fact and such examination of law as we have deemed appropriate in order to enable us to render the opinions set forth herein. In conducting such investigation, we have relied, without independent verification, upon certificates of officers of the Company, public officials and other appropriate persons.

The opinions expressed below are limited to the Delaware General Corporation Law.

Based upon and subject to the foregoing, we are of the opinion that the Shares have been duly authorized and, when the Shares have been issued and sold in accordance with the terms of the Inducement Award Agreements, the Shares will be validly issued, fully paid and nonassessable.

Zenas BioPharma, Inc.

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

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| |
|:---|
| Very truly yours, |
| /s/ Ropes & Gray LLP |
| Ropes & Gray LLP |

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## Exhibit 23.1

**Exhibit 23.1**

**Consent of Independent Registered Public Accounting Firm**

We consent to the incorporation by reference in the Registration Statement (Form S-8) pertaining to the Inducement Option Award Agreements of Zenas BioPharma, Inc. of our report dated March 11, 2025, with respect to the consolidated financial statements of Zenas BioPharma, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2024, filed with the Securities and Exchange Commission.

/s/ Ernst & Young LLP

Boston, Massachusetts

August 12, 2025

## Ex-Filing

?xml version='1.0' encoding='ASCII'? EX-FILING FEES

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| |
|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Calculation of Filing Fee Tables**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **S-8**  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Zenas BioPharma, Inc.**  |

---

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| | | | | | | | | |
|:---|:---|:---|:---|:---|:---|:---|:---|:---|
| | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Type**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Security Class Title**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Calculation Rule**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount Registered**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Proposed Maximum Offering Price Per Unit**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Maximum Aggregate Offering Price**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Fee Rate**  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Amount of Registration Fee**  |
| 1 | Equity | Common Stock, $0.0001 par value per share | Other | 400000 | $8.72 | $3488000.00 | 0.0001531 | $534.01 |
| 2 | Equity | Common Stock, $0.0001 par value per share | Other | 250000 | $8.72 | $2180000.00 | 0.0001531 | $333.76 |
| 3 | Equity | Common Stock, $0.0001 par value per share | Other | 112000 | $9.97 | $1116640.00 | 0.0001531 | $170.96 |
| Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: | Total Offering Amounts: |  | $6784640.00  |  | $1038.73  |
| Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  | Total Fee Offsets:  |  |  |  | $0.00  |
| Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  | Net Fee Due:  |  |  |  | $1038.73  |

---

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; **Offering Note** <br>

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>1</sup> Offering Note 1.a Pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Act") this Registration Statement also covers such additional shares of common stock, par value $0.0001 per share ("Common Stock") as may be issued to prevent dilution from stock splits, stock dividends and similar transactions. Offering Note 1.b Consists of shares of common stock of the Registrant issuable under new hire inducement stock option awards as an inducement material to entry into employment with the Registrant in accordance with Nasdaq Listing Rule 5635(c)(4). Offering Note 1.c Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(h) of the Act. The proposed maximum offering price per share and the maximum aggregate offering price a calculated based on the exercise price of the options outstanding under the applicable inducement stock option awards. Offering Note 1.d The inducement stock option awards were granted on April 15, 2025 with an exercise price equal to the closing price of the Registrant's common stock on the Nasdaq Global Select Market on such date.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>2</sup> See Offering Note 1.a, 1.b & 1.c Offering Note 2 The inducement stock option awards were granted on April 15, 2025 with an exercise price equal to the closing price of the Registrant's common stock on the Nasdaq Global Select Market on such date.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <sup>3</sup> See Offering Note 1.a, 1.b & 1.c Offering Note 3 The inducement stock option awards were granted on June 16, 2025 with an exercise price equal to the closing price of the Registrant's common stock on the Nasdaq Global Select Market on such date.

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| | |
|:---|:---|
| | |
| **Rule 457(p)** | **Rule 457(p)** |
| Fee Offset Claims | N/A |
| Fee Offset Sources | N/A |

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