Avidity Biosciences, Inc. SEC Filings

Avidity Biosciences insider activity: Teresa McCarthy, Chief Human Resources Officer, effected option exercise and share sales under a Rule 10b5-1 plan on 08/15/2025. She exercised a stock option with a $22.34 exercise price for 10,000 shares and immediately sold 10,000 common shares in multiple transactions at a weighted-average price of $46.5632, with trade prices ranging $45.36 to $47.50. After these transactions the reporting person beneficially owned 97,130 shares of common stock and held options covering 100,000 shares. The option shares were fully vested as of the exercise date.

Avidity Biosciences, Inc. (RNA) reported a proposed sale under Rule 144 of 45,000 common shares through Morgan Stanley Smith Barney LLC with an aggregate market value of $2,073,150.00. The filing indicates the shares were acquired and are to be sold on 08/15/2025 following the exercise of stock options granted by the issuer, with payment made in cash. The company has 128,653,337 shares outstanding, and the filer reports no other sales in the past three months. The filer certifies they are not aware of undisclosed material adverse information and follows the Rule 144 attestation requirements.

Michael F. MacLean, Chief Financial Officer of Avidity Biosciences, Inc. (RNA), reported insider stock sales on a Form 4. On 08/06/2025 he disposed of 30,914 shares of Avidity common stock under a Rule 10b5-1 trading plan adopted 07/08/2024 at a weighted-average price of $42.7264 per share (individual sale prices ranged from $40.15 to $43.92). After the reported transactions he beneficially owned 65,806 shares. The Form 4 was signed by an attorney-in-fact on 08/15/2025. The filing states the reporting person will provide details on the number of shares sold at each price upon request.

Avidity Biosciences insider Steven George executed transactions under a previously adopted Rule 10b5-1 plan, reducing his direct common stock holdings. On 08/13/2025 he acquired 1,542 shares via option exercise at a $6.57 exercise price and simultaneously sold 1,542 shares at $46.66 per share. After the transactions his direct beneficial ownership declined from 40,409 to 38,867 shares. The option that was exercised was granted on 09/11/2023 and vests monthly in equal installments, becoming fully exercisable on 09/11/2027. The 10b5-1 plan was adopted on 06/12/2024.

Avidity Biosciences (RNA) Form 144 notice: The filing reports a proposed sale of 9,709 common shares on 08/13/2025 through Morgan Stanley Smith Barney LLC on NASDAQ, with an aggregate market value of $448,847.07. The securities were recorded as acquired on 08/13/2025 by exercise of stock options and paid in cash. The filing also discloses prior 10b5-1 sales by the same person on 08/06/2025 of 81,434 shares for $3,480,272.61. The filer represents they do not know any material nonpublic information.

Eric Mosbrooker, Chief Commercial Officer of Avidity Biosciences (RNA), reported option exercise and share sales on 08/06/2025. He exercised 124,687 stock options at an exercise price of $9.05, generating 124,687 common shares. Those shares and additional holdings were sold in multiple transactions under a Rule 10b5-1 trading plan adopted on September 11, 2024 at a weighted-average sale price of $44.0626 (range $40.54–$45.44).

The Form 4 shows total reported sales of 130,807 shares (124,687 + 6,120) and a reported direct beneficial ownership in common stock of 55,000 shares following the transactions. The filing also reports 190,313 derivative securities beneficially owned following the transactions and discloses an option vesting schedule of 1/48th monthly beginning January 1, 2024.

Troy Edward Wilson, a director of Avidity Biosciences, Inc. (RNA), executed option exercises and share sales on 08/06/2025 under a previously adopted Rule 10b5-1 trading plan. He exercised 22,000 options at an exercise price of $12.03 and 7,500 options at $12.48, and sold shares at $45.00 per share pursuant to the plan.

Following the reported transactions the filing shows 69,425 shares held directly by the reporting person. The Form 4 also lists indirect beneficial ownership via several irrevocable trusts and a family trust, shown as 285,000, 285,000, 17,776, 17,776, 11,851, 11,851, and 13,711 shares. The filing states the 10b5-1 plan was adopted on December 4, 2024 and that all option shares were fully vested and exercisable at the time of exercise.

Arthur A. Levin, a director of Avidity Biosciences (RNA), reported both the exercise of stock options and the sale of shares on 08/06/2025. He exercised options to acquire 107,500 shares at an exercise price of $22.34 per share; the option is noted as fully vested and exercisable. The same 107,500 shares were sold under a Rule 10b5-1 trading plan adopted on October 17, 2024 at a weighted-average price of $47.6175 per share, with trade prices reported in a range of $47.50–$48.02.

Following these transactions the reporting person directly beneficially owned 19,650 shares. The filing also discloses indirect holdings of 131,372 shares through a family trust and 22,500 shares through a charitable remainder trust. The related option shows an expiration date of 02/01/2031.

Steven George Hughes, Chief Medical Officer of Avidity Biosciences (RNA), reported multiple option exercises and subsequent sales on 08/06/2025. He exercised options with strike prices of $15.96, $6.57, $22.47, and $10.16, acquiring 11,283, 12,334, 6,167, and 17,667 shares respectively. Several of the acquired shares were sold the same day under a Rule 10b5-1 trading plan adopted June 12, 2024.

Sales were reported at a weighted-average price of $42.7373 with transaction prices ranging from $40.15 to $46.44. The filing shows the reporting person’s direct beneficial ownership of common stock following the transactions as 38,867 shares. The Form 4 also includes grant dates and monthly vesting schedules for each option grant.