Director-linked funds add 75K Zenas BioPharma (ZBIO) shares at $20 in offering

Rhea-AI Filing Summary

Zenas BioPharma, Inc. director-associated investment entities acquired additional common stock in an underwritten public offering. Entities affiliated with Hongbo Lu purchased 75,000 shares of common stock at $20.00 per share, and now hold 422,968 shares indirectly after the transaction. The securities are owned directly by NEXTBio Master Fund LP or NEXTBio Evergreen LLC, with various NEXTBio management entities and Hongbo Lu potentially deemed indirect beneficial owners, subject to a formal disclaimer of beneficial ownership beyond any pecuniary interest.

Insider Trade Summary

Net Buyer: 75,000 shares ($1,500,000)

Net Buy 1 txn

Insider Lu Hongbo

Role Director

Bought 75,000 shs ($1.50M)

Type	Security	Shares	Price	Value
Purchase	Common Stock	75,000	$20.00	$1.50M

Holdings After Transaction: Common Stock — 422,968 shares (Indirect, See footnote)

Footnotes (1)

1. Acquired in an underwritten public offering, pursuant to which Zenas BioPharma, Inc. sold shares of common stock at a purchase price of $20.00 per share. The reported securities are owned directly by NEXTBio Master Fund LP or NEXTBio Evergreen LLC and may be deemed to be indirectly beneficially owned by (i) NEXTBio Capital LLC, the general partner of NEXTBio Master Fund LP (with respect to such securities directly owned by NEXTBio Master Fund LP), (ii) NEXTBio Capital Evergreen GP LLC, the managing member of NEXTBio Evergreen LLC (with respect to such securities directly owned by NEXTBio Evergreen LLC), (iii) NEXTBio Capital Management LP, the investment manager to NEXTBio Master Fund LP and NEXTBio Evergreen LLC, and (iv) Hongbo Lu, a managing member of NEXTBio Capital LLC and NEXTBio Capital Evergreen GP LLC. The Reporting Person disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

Key Figures

Shares purchased: 75,000 shares Purchase price: $20.00 per share Indirect holdings after transaction: 422,968 shares

3 metrics

Shares purchased 75,000 shares Open-market style purchase in underwritten public offering

Purchase price $20.00 per share Price in the underwritten public offering

Indirect holdings after transaction 422,968 shares Total indirect position reported after the purchase

Key Terms

underwritten public offering, indirectly beneficially owned, pecuniary interest, Section 16 of the Securities Exchange Act of 1934

4 terms

underwritten public offering financial

"Acquired in an underwritten public offering, pursuant to which Zenas BioPharma, Inc. sold shares"

An underwritten public offering is when a company sells new shares of its stock to the public with the help of a financial firm, called an underwriter. The underwriter agrees to buy all the shares upfront, reducing the company's risk, and then sells them to investors. This process helps companies raise money quickly and confidently from a wide range of buyers.

indirectly beneficially owned financial

"may be deemed to be indirectly beneficially owned by (i) NEXTBio Capital LLC"

pecuniary interest financial

"disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein"

Section 16 of the Securities Exchange Act of 1934 regulatory

"for purposes of Section 16 of the Securities Exchange Act of 1934, as amended"

A provision of federal securities law that requires company insiders—directors, officers and large shareholders—to publicly report their stock holdings and trades and to surrender any “short-swing” profits from purchases and sales within a six-month window. It acts like a rule that forces leaders to announce their trades and prevents quick buy-sell windfalls, giving investors transparency into insider activity and reducing opportunities for unfair gain.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Lu Hongbo

(Last) (First) (Middle)

C/O ZENAS BIOPHARMA, INC.

852 WINTER ST., SUITE 250

(Street)

WALTHAM MASSACHUSETTS 02451

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Zenas BioPharma, Inc. [ ZBIO ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/31/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/31/2026		P(1)		75,000	A	$20	422,968	I(2)(3)	See footnote(2)(3)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Acquired in an underwritten public offering, pursuant to which Zenas BioPharma, Inc. sold shares of common stock at a purchase price of $20.00 per share.

2. The reported securities are owned directly by NEXTBio Master Fund LP or NEXTBio Evergreen LLC and may be deemed to be indirectly beneficially owned by (i) NEXTBio Capital LLC, the general partner of NEXTBio Master Fund LP (with respect to such securities directly owned by NEXTBio Master Fund LP), (ii) NEXTBio Capital Evergreen GP LLC, the managing member of NEXTBio Evergreen LLC (with respect to such securities directly owned by NEXTBio Evergreen LLC), (iii) NEXTBio Capital Management LP, the investment manager to NEXTBio Master Fund LP and NEXTBio Evergreen LLC, and (iv) Hongbo Lu, a managing member of NEXTBio Capital LLC and NEXTBio Capital Evergreen GP LLC.

3. The Reporting Person disclaims beneficial ownership of the reported securities except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person is the beneficial owner of the securities for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose.

	Hongbo Lu, By: /s/ Hongbo Lu	03/31/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider share purchase did Zenas BioPharma (ZBIO) report in this Form 4?

Zenas BioPharma reported that entities affiliated with director Hongbo Lu bought 75,000 shares of common stock. The shares were acquired at $20.00 per share in an underwritten public offering, increasing the affiliated entities’ indirect holdings to 422,968 shares.

At what price were the Zenas BioPharma (ZBIO) shares acquired in the reported transaction?

The reported entities acquired Zenas BioPharma common stock at a purchase price of $20.00 per share. This price reflects the terms of an underwritten public offering in which Zenas BioPharma sold newly issued shares directly into the market.

How many Zenas BioPharma (ZBIO) shares are held after the transaction by the reporting entities?

Following the transaction, the entities associated with Hongbo Lu indirectly hold 422,968 shares of Zenas BioPharma common stock. This figure represents the total reported indirect position after purchasing 75,000 additional shares in the underwritten public offering.

Who actually owns the Zenas BioPharma (ZBIO) shares reported in Hongbo Lu’s Form 4?

The shares are owned directly by NEXTBio Master Fund LP or NEXTBio Evergreen LLC. They may be deemed indirectly beneficially owned by several NEXTBio management entities and by Hongbo Lu, subject to a disclaimer limiting beneficial ownership to any pecuniary interest.

Was the Zenas BioPharma (ZBIO) insider purchase part of a public offering?

Yes. The Form 4 states the shares were acquired in an underwritten public offering in which Zenas BioPharma sold common stock at $20.00 per share. The reported 75,000-share purchase occurred under those offering terms.

Does Hongbo Lu fully accept beneficial ownership of the reported Zenas BioPharma (ZBIO) shares?

No. The filing notes that the reporting person disclaims beneficial ownership of the securities except to the extent of any pecuniary interest. It also specifies that this disclaimer applies for Section 16 and other legal purposes.