RA Capital (NASDAQ: ACET) exchanges 250K Adicet Bio shares for pre-funded warrant

Rhea-AI Filing Summary

Adicet Bio, Inc. reported that an affiliate of RA Capital restructured part of its position through an exchange. On April 27, 2026, RA Capital Healthcare Fund, L.P. entered into an Exchange Agreement to swap 250,000 shares of Adicet Bio common stock for a pre-funded warrant for up to 250,000 common shares at an exercise price of $0.0001 per share, for no additional consideration. Following the transactions, the Fund held 932,624 shares of common stock and 1,402,833 pre-funded warrant shares indirectly. The pre-funded warrant is exercisable immediately, has no expiration date, and includes a 9.99% beneficial ownership limit that prevents exercises above that level when combined with Attribution Parties.

Insights

Equity ownership & derivatives analyst

RA Capital reclassified 250,000 Adicet shares into a pre-funded warrant with no net buy or sale.

The disclosure shows RA Capital Healthcare Fund exchanging 250,000 Adicet Bio common shares for a pre-funded warrant over the same number of shares at an exercise price of $0.0001, with no additional consideration. This is coded as an "other" restructuring transaction, not an open-market trade.

After the exchange, the Fund reports 932,624 common shares and 1,402,833 pre-funded warrant shares held indirectly, so its overall economic exposure remains substantial. The warrant is immediately exercisable with no expiration but is constrained by a 9.99% beneficial ownership cap, which limits how many shares can be exercised at once relative to Adicet Bio’s outstanding common stock.

Footnotes state that RA Capital Management, its general partner, and individuals Peter Kolchinsky and Rajeev Shah disclaim beneficial ownership beyond their pecuniary interests. This underscores that the filing reflects fund-level restructuring of exposure rather than a directional buy or sell signal by the individuals.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider RA CAPITAL MANAGEMENT, L.P., RA Capital Healthcare Fund LP, Kolchinsky Peter, Shah Rajeev M.

Role null | null | null | null

Type	Security	Shares	Price	Value
Other	Pre-Funded Warrant (Right to Buy)	250,000	$0.00	--
Other	Common Stock	250,000	$0.00	--

Holdings After Transaction: Pre-Funded Warrant (Right to Buy) — 1,402,833 shares (Indirect, See footnotes); Common Stock — 932,624 shares (Indirect, See footnotes)

Footnotes (1)

1. On April 27, 2026, RA Capital Healthcare Fund, L.P. (the "Fund") entered into an Exchange Agreement with the Issuer pursuant to which the Fund exchanged, for no additional consideration, 250,000 shares of the Issuer's Common Stock for a pre-funded warrant exercisable for up to 250,000 shares of the Issuer's Common Stock at an exercise price of $0.0001 per share (the "Pre-Funded Warrant"). RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund"). The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein. Held directly by the Fund. The Pre-Funded Warrant has no expiration date and is exercisable immediately. Notwithstanding the foregoing, the Fund shall not be entitled to exercise the Pre-Funded Warrant to the extent that it would cause the aggregate number of shares of Common Stock beneficially owned by the Fund, together with its Attribution Parties (as defined in the Pre-Funded Warrant), to exceed 9.99% of the total number of issued and outstanding shares of Common Stock of the Issuer following such exercise.

Key Figures

Common shares exchanged: 250,000 shares Warrant underlying shares: 250,000 shares Warrant exercise price: $0.0001 per share +4 more

7 metrics

Common shares exchanged 250,000 shares Common stock swapped for pre-funded warrant on April 27, 2026

Warrant underlying shares 250,000 shares Pre-funded warrant right to buy Adicet common stock

Warrant exercise price $0.0001 per share Exercise price for pre-funded warrant

Common shares after transaction 932,624 shares Fund’s indirect Adicet common stock position following restructuring

Pre-funded warrant shares after transaction 1,402,833 shares Total pre-funded warrant-linked shares held indirectly after transaction

Beneficial ownership cap 9.99% Maximum beneficial ownership allowed upon warrant exercise with Attribution Parties

Restructuring share volume 500,000 shares Total shares involved across both restructuring transactions

Key Terms

Exchange Agreement, Pre-Funded Warrant, beneficial ownership, pecuniary interest, +2 more

6 terms

Exchange Agreement financial

"entered into an Exchange Agreement with the Issuer pursuant to which"

Pre-Funded Warrant financial

"for a pre-funded warrant exercisable for up to 250,000 shares"

A pre-funded warrant is a financial instrument that gives the holder the right to buy shares of a company's stock at a set price, with most of the purchase cost already paid upfront. It functions like a nearly fully paid option, allowing investors to secure shares quickly while minimizing the amount of additional money they need to invest later. This helps investors gain ownership rights efficiently, often used to avoid certain regulatory restrictions or to prepare for future stock purchases.

beneficial ownership financial

"disclaims beneficial ownership of any of the reported securities, except"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

pecuniary interest financial

"disclaims beneficial ownership ... except to the extent of its or his respective pecuniary interest"

Attribution Parties financial

"together with its Attribution Parties (as defined in the Pre-Funded Warrant)"

issued and outstanding shares financial

"9.99% of the total number of issued and outstanding shares of Common Stock"

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

X

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^*

RA CAPITAL MANAGEMENT, L.P.

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Adicet Bio, Inc. [ ACET ]

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

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

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
04/27/2026

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

	Form filed by One Reporting Person
X	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	04/27/2026		J(1)		250,000	D	(1)	932,624	I	See footnotes(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
Pre-Funded Warrant (Right to Buy)	$0.0001	04/27/2026		J(1)		250,000		(4)	(1)	Common Stock	250,000	(1)	1,402,833	I	See footnotes(2)(3)

1. Name and Address of Reporting Person^*

RA CAPITAL MANAGEMENT, L.P.

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

RA Capital Healthcare Fund LP

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

Kolchinsky Peter

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

1. Name and Address of Reporting Person^*

Shah Rajeev M.

(Last) (First) (Middle)

C/O RA CAPITAL MANAGEMENT, L.P.

200 BERKELEY STREET, 18TH FLOOR

(Street)

BOSTON MASSACHUSETTS 02116

(City) (State) (Zip)

UNITED STATES

(Country)

Relationship of Reporting Person(s) to Issuer

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

Explanation of Responses:

1. On April 27, 2026, RA Capital Healthcare Fund, L.P. (the "Fund") entered into an Exchange Agreement with the Issuer pursuant to which the Fund exchanged, for no additional consideration, 250,000 shares of the Issuer's Common Stock for a pre-funded warrant exercisable for up to 250,000 shares of the Issuer's Common Stock at an exercise price of $0.0001 per share (the "Pre-Funded Warrant").

2. RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund"). The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. Each of the Adviser, the Adviser GP, the Fund, Dr. Kolchinsky and Mr. Shah disclaims beneficial ownership of any of the reported securities, except to the extent of its or his respective pecuniary interest therein.

3. Held directly by the Fund.

4. The Pre-Funded Warrant has no expiration date and is exercisable immediately. Notwithstanding the foregoing, the Fund shall not be entitled to exercise the Pre-Funded Warrant to the extent that it would cause the aggregate number of shares of Common Stock beneficially owned by the Fund, together with its Attribution Parties (as defined in the Pre-Funded Warrant), to exceed 9.99% of the total number of issued and outstanding shares of Common Stock of the Issuer following such exercise.

	/s/ Peter Kolchinsky, Manager of RA Capital Management, L.P.	04/29/2026
	/s/ Peter Kolchinsky, Manager of RA Capital Healthcare Fund GP, LLC, the General Partner of RA Capital Healthcare Fund, L.P.	04/29/2026
	/s/ Peter Kolchinsky, individually	04/29/2026
	/s/ Rajeev Shah, individually	04/29/2026
	** 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 transaction did RA Capital report in this Adicet Bio (ACET) Form 4?

RA Capital Healthcare Fund, L.P. exchanged 250,000 shares of Adicet Bio common stock for a pre-funded warrant exercisable for up to 250,000 common shares. The exchange occurred for no additional consideration and is classified as an "other" restructuring transaction, not a market purchase or sale.

How many Adicet Bio (ACET) shares and warrants does the RA Capital fund hold after the transaction?

After the restructuring, RA Capital Healthcare Fund held 932,624 shares of common stock and 1,402,833 pre-funded warrant shares indirectly. These figures reflect the post-transaction ownership reported, combining the remaining stock position with the warrant-linked common share equivalents.

What are the key terms of the pre-funded warrant reported for Adicet Bio (ACET)?

The pre-funded warrant is exercisable for up to 250,000 common shares at an exercise price of $0.0001 per share. It is exercisable immediately, has no expiration date, and represents a very low-cost way for the holder to convert into common stock.

Does the Adicet Bio (ACET) pre-funded warrant have a beneficial ownership limit?

Yes. The pre-funded warrant cannot be exercised to the extent it would cause the Fund and its Attribution Parties to beneficially own more than 9.99% of Adicet Bio’s outstanding common stock after exercise. This cap limits how much of the warrant can be exercised at any one time.

Who is considered to hold the Adicet Bio (ACET) securities in this Form 4 filing?

The securities are held directly by RA Capital Healthcare Fund, L.P.. RA Capital Management, L.P., its general partner RA Capital Management GP, LLC, and individuals Peter Kolchinsky and Rajeev Shah act through these entities and disclaim beneficial ownership beyond their respective pecuniary interests.

Was there any cash consideration paid in the Adicet Bio (ACET) share-for-warrant exchange?

No. The Form 4 states that the Fund exchanged 250,000 common shares for a pre-funded warrant over 250,000 shares for no additional consideration. The transaction restructures how exposure is held without reflecting an open-market cash purchase or sale.