Avidity Biosciences (RNA) director disposes options in $72 Novartis merger

Rhea-AI Filing Summary

Avidity Biosciences director Carsten Boess reported dispositions of stock options and common shares in connection with the company’s acquisition by Novartis. Several “Stock Option (Right to Buy)” awards and 6,692 shares of common stock were transferred to the issuer under the merger agreement.

The options were canceled in exchange for a cash payment equal to the excess of the merger consideration of $72.00 per share over each option’s exercise price, reflecting cash-out treatment rather than open-market sales.

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

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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^*

BOESS CARSTEN

(Last) (First) (Middle)

C/O AVIDITY BIOSCIENCES, INC.

3020 CALLAN RD.

(Street)

SAN DIEGO CA 92121

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Avidity Biosciences, Inc. [ RNAM ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
02/27/2026

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

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

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

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	02/27/2026		D		6,692(1)	D	(1)	0	D

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
Stock Option (Right to Buy)	$33.62	02/27/2026		D			10,034	(2)	06/09/2035	Common Stock	10,034	(2)	0	D
Stock Option (Right to Buy)	$39.96	02/27/2026		D			13,489	(2)	06/12/2034	Common Stock	13,489	(2)	0	D
Stock Option (Right to Buy)	$12.48	02/27/2026		D			22,000	(2)	06/14/2033	Common Stock	22,000	(2)	0	D
Stock Option (Right to Buy)	$12.03	02/27/2026		D			22,000	(2)	06/14/2032	Common Stock	22,000	(2)	0	D
Stock Option (Right to Buy)	$26.09	02/27/2026		D			15,000	(2)	06/15/2031	Common Stock	15,000	(2)	0	D
Stock Option (Right to Buy)	$8.82	02/27/2026		D			20,858	(2)	05/14/2030	Common Stock	20,858	(2)	0	D

Explanation of Responses:

1. The reported securities represent shares of Common Stock (inclusive of shares of Common Stock issuable upon settlement of previously reported restricted stock units) disposed of pursuant to the terms of the Agreement and Plan of Merger, dated as of October 25, 2025 (the "Merger Agreement"), among Novartis AG ("Novartis"), Ajax Acquisition Sub, Inc., an indirect wholly owned subsidiary of Novartis, and the Issuer.

2. The reported Options were disposed of, pursuant to the Merger Agreement, in exchange for a cash payment equal to the excess of the merger consideration of $72.00 over the exercise price.

	/s/ John B. Moriarty, Jr., J.D., Attorney-in-Fact	02/27/2026
	** Signature of Reporting Person	Date
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FAQ

What insider transaction did Avidity Biosciences (RNA) report on this Form 4?

Avidity Biosciences director Carsten Boess reported multiple dispositions of stock options and 6,692 shares of common stock. The transactions were issuer dispositions tied to Avidity’s merger agreement with Novartis, not open-market trades, and reflect merger-related consideration mechanics.

How were Carsten Boess’s Avidity stock options treated in the Novartis merger?

The reported Avidity stock options were disposed of under the merger agreement and exchanged for cash. Each option received a payment equal to the merger consideration of $72.00 per share minus its exercise price, effectively cashing out the in-the-money value.

What happened to Avidity Biosciences common shares held by Carsten Boess?

Shares of Avidity common stock held by Carsten Boess, including shares issuable from previously reported restricted stock units, were disposed of pursuant to the merger agreement. These securities were converted into merger consideration in connection with Novartis’s acquisition of Avidity Biosciences.

Do these Avidity (RNA) Form 4 transactions represent open-market selling?

No, the Form 4 transactions are coded as dispositions to the issuer, not market sales. The stock options and common shares were canceled or converted pursuant to the merger agreement with Novartis, receiving cash or merger consideration at the specified $72.00 per-share merger price.

What role does Novartis play in Carsten Boess’s reported Avidity transactions?

Novartis is the acquirer in Avidity’s merger, acting through Ajax Acquisition Sub, Inc. Under the merger agreement, Boess’s Avidity stock options and common shares were disposed of and exchanged for cash or merger consideration based on the stated $72.00 per-share merger consideration.