Avidity Biosciences (RNA) CMO executes option exercise and sale under 10b5-1 plan

Rhea-AI Filing Summary

Steven George Hughes, Chief Medical Officer of Avidity Biosciences, Inc. (RNA), reported exercises and a sale on 09/15/2025 under a previously adopted Rule 10b5-1 trading plan. He exercised 1,542 stock options with an exercise price of $6.57 and simultaneously sold 1,542 shares at $45.41. Following the reported transactions, the Form shows 38,867 shares beneficially owned as direct holdings in the non-derivative table and 49,333 derivative securities (options) beneficially owned in the derivative table. The options vest monthly (1/48th) beginning 09/11/2023 and fully vest on the fourth anniversary, subject to continued service. The transactions were effected under a 10b5-1 plan adopted 06/12/2024.

Positive

• Trades executed under a Rule 10b5-1 plan, indicating pre-established trading instructions adopted 06/12/2024
• Exercise price of $6.57 on 1,542 options indicates option exercise at a lower strike relative to the sale price
• Vesting schedule disclosed (1/48th monthly from 09/11/2023, fully vested on fourth anniversary), providing clarity on future option vesting

Negative

• Insider sold 1,542 shares at $45.41 on 09/15/2025, representing insider liquidity which may be viewed negatively by some investors
• Direct holdings decreased to 38,867 shares in the non-derivative table after the sale

Insights

Securities Analyst

TL;DR Insider exercised options and sold an equal number of shares under a pre-established 10b5-1 plan; impact appears routine.

The exercise at $6.57 and contemporaneous sale at $45.41 generated realized proceeds for the reporting person while leaving significant direct and derivative holdings. The filing discloses standard vesting (1/48th monthly) and a 10b5-1 plan adoption date, which supports that trades were pre-planned and not opportunistic. For investors, the transaction documents insider liquidity but does not, by itself, indicate change in company fundamentals.

Corporate Governance Expert

TL;DR Transactions follow prescribed governance controls (10b5-1 plan), suggesting compliance and routine insider liquidity.

The Form 4 clearly states the trades were executed under a 10b5-1 plan adopted 06/12/2024 and includes the required explanation and signature by an attorney-in-fact. Vesting schedule details are provided, indicating continued service conditions. These disclosures align with standard governance and insider reporting practices.

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).

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)
09/15/2025

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	09/15/2025		M(1)		1,542	A	$6.57	40,409	D
Common Stock	09/15/2025		S(1)		1,542	D	$45.41	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)	$6.57	09/15/2025		M(1)			1,542	(2)	09/10/2033	Common Stock	1,542	$0	49,333	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. 1/48th of the total number of shares subject to the options shall vest on each monthly anniversary of September 11, 2023 (the "Vesting Commencement Date"), subject to the Reporting Person's continuous service to the Issuer on each such vesting date, so that the option shall be fully vested on the fourth anniversary of the Vesting Commencement Date.

Remarks:

	/s/ John B. Moriarty, Jr., J.D., Attorney-in-Fact	09/17/2025
	** 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 transactions did Steven G. Hughes report on Form 4 for RNA?

He reported the exercise of 1,542 options at an exercise price of $6.57 and the sale of 1,542 shares at $45.41 on 09/15/2025.

Were the trades executed under a trading plan for Avidity Biosciences (RNA)?

Yes. The exercises and sales were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 06/12/2024.

How many shares and options does the filing show beneficially owned after the transactions?

The filing shows 38,867 shares beneficially owned (direct) in the non-derivative table and 49,333 derivative securities (options) beneficially owned in the derivative table.

What is the vesting schedule for the options referenced in the Form 4?

Options vest at 1/48th of the total each monthly anniversary beginning 09/11/2023, fully vesting on the fourth anniversary, subject to continuous service.

Who signed the Form 4 filing for the reporting person?

The Form 4 was signed by John B. Moriarty, Jr., J.D., Attorney-in-Fact on 09/17/2025.