[Form 4] Avidity Biosciences, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Avidity Biosciences (RNA) reported insider activity by its Chief Medical Officer. On October 22, 2025, the officer exercised a stock option for 2,209 shares at $10.16 and sold 2,209 shares at a weighted-average price of $47.5394, executed under a Rule 10b5-1 trading plan adopted on June 12, 2024.

Following these transactions, the officer held 38,867 shares of common stock directly and 68,458 derivative securities (stock options). The referenced option was granted on January 20, 2024 and vests in equal monthly installments of 2,208 shares until fully vested and exercisable on January 20, 2028.

Insights

Insider trading compliance analyst

Routine Form 4: option exercise and sale under a 10b5-1 plan.

The CMO exercised an option at $10.16 for 2,209 shares and sold the same number at a weighted-average $47.5394 on October 22, 2025. The filing states these were executed pursuant to a Rule 10b5-1 plan adopted on June 12, 2024, indicating pre-arranged trading parameters.

Post-transaction holdings are 38,867 common shares and 68,458 derivative securities. The option referenced was granted on January 20, 2024 and vests monthly in 2,208-share increments until fully vested by January 20, 2028. Actual market impact depends on overall float and trading volume, which are not detailed here.

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).

X

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^*

Hughes Steven George

(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. [ RNA ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
10/22/2025

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	10/22/2025		M(1)		2,209	A	$10.16	41,076	D
Common Stock	10/22/2025		S(1)		2,209	D	$47.5394(2)	38,867	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)	$10.16	10/22/2025		M(1)			2,209	(3)	01/19/2034	Common Stock	2,209	$0	68,458	D

Explanation of Responses:

1. The exercises and sales reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan previously adopted by the Reporting Person on June 12, 2024.

2. This represents a weighted-average price. These shares were sold in multiple transactions at prices ranging from $46.83 to $49.30. The Reporting Person undertakes to provide the Issuer, any securityholder of the Issuer, or the Staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

3. This option was granted on January 20, 2024 and vests in equal installments of 2,208 shares on each monthly anniversary of such grant date, until it is fully vested and exercisable on January 20, 2028.

Remarks:

	/s/ John B. Moriarty, Jr., J.D., Attorney-in-Fact	10/24/2025
	** 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.

FAQ

What did Avidity Biosciences (RNA) disclose in this Form 4?

The CMO exercised an option for 2,209 shares at $10.16 and sold 2,209 shares at a $47.5394 weighted-average price on October 22, 2025.

Was the RNA insider trade under a Rule 10b5-1 plan?

Yes. The filing states the transactions were executed under a Rule 10b5-1 plan adopted on June 12, 2024.

How many Avidity Biosciences shares does the insider own after the trade?

Following the transactions, the officer directly owned 38,867 common shares and held 68,458 derivative securities (stock options).

What price were the shares sold for in the RNA Form 4?

Shares were sold at a weighted-average price of $47.5394, with individual trades ranging from $46.83 to $49.30.

What are the vesting terms of the reported stock option?

The option was granted on January 20, 2024 and vests in equal monthly installments of 2,208 shares until fully vested and exercisable on January 20, 2028.

What is the insider’s role at Avidity Biosciences (RNA)?

The reporting person is the company’s Chief Medical Officer.