Welcome to our dedicated page for Atrium Therapeutics SEC filings (Ticker: RNA), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Atrium Therapeutics filings document the corporate transition that created the current RNA issuer and the related Avidity Biosciences merger, separation and listing records. The filing set includes 8-K material-event reports, shareholder voting disclosures, separation and merger agreement records, capital-structure information and a Form 25 covering removal of Avidity common stock from Nasdaq listing and registration.
Regulatory disclosures tied to the symbol also cover governance matters, operating and financial results, clinical or regulatory updates and security-structure information. As an independent biopharmaceutical company, Atrium's filings center on its RNA therapeutics platform, precision cardiology pipeline, collaboration economics, equity compensation and public-company reporting obligations.
T. Rowe Price Associates, Inc. reported beneficial ownership of 1,553,210 shares of Atrium Therapeutics common stock, representing 10.0% of the class as of 03/31/2026. The filing lists sole voting power of 1,552,984 shares and sole dispositive power of 1,553,210 shares. The Schedule 13G is signed by a T. Rowe Price officer on 04/08/2026.
Avidity Biosciences, Inc. reported that Chief Human Resources Officer Teresa McCarthy disposed of company equity in connection with the previously agreed merger with Novartis AG. The filing shows an issuer disposition of multiple stock option awards and 165,296 shares of Common Stock, including shares underlying previously reported restricted stock units.
According to the merger terms, each reported share of Common Stock was converted into the cash merger consideration of $72.00 per share. The stock options were canceled in exchange for a cash payment equal to the excess of the $72.00 merger price over their exercise price, indicating these were cash-settled, merger-related transactions rather than open-market trades.
Avidity Biosciences director Tamar Thompson reported disposing of all her Avidity equity in connection with the company’s merger with Novartis. Footnotes state that her common stock, including shares underlying previously reported restricted stock units, was transferred to the issuer under the merger agreement, and her stock options were cancelled in exchange for cash equal to the merger consideration of $72.00 per share minus each option’s exercise price. Following these issuer dispositions on February 27, 2026, her reported holdings of both common stock and options are shown as zero.
Avidity Biosciences chief financial officer Michael F. MacLean reported disposing of company equity in connection with the company’s merger with Novartis AG. The filing shows multiple dispositions of stock options and 133,977 shares of common stock as issuer dispositions, rather than open-market sales.
According to the disclosure, the common shares, including shares issuable from previously reported restricted stock units, were disposed of under the October 25, 2025 Merger Agreement among Novartis, Ajax Acquisition Sub, Inc., and Avidity Biosciences. The reported stock options were cancelled in exchange for cash equal to the merger consideration of $72.00 per share minus each option’s exercise price.
Avidity Biosciences, Inc. director Simona Skerjanec reported disposing of equity awards in connection with a pending acquisition. On February 27, 2026, she disposed of 10,034 and 42,308 stock options and 6,692 shares of common stock in issuer dispositions. Footnotes state these securities were cashed out under an Agreement and Plan of Merger dated October 25, 2025 among Novartis AG, Ajax Acquisition Sub, Inc., and Avidity Biosciences, with options exchanged for cash equal to the merger consideration of $72.00 per share minus the exercise price.
Avidity Biosciences’ Chief Medical Officer, Steven George Hughes, reported the disposition of his equity in connection with the company’s merger with Novartis. The filing shows shares of Common Stock, including shares underlying previously reported restricted stock units, were disposed of pursuant to an Agreement and Plan of Merger among Novartis AG, Ajax Acquisition Sub, Inc., and Avidity Biosciences. Several stock option grants were also disposed of. Under the merger terms, these options were exchanged for cash equal to the excess of the merger consideration of $72.00 per share over each option’s exercise price, reflecting a cash-out of his options and common stock as part of the transaction.
Avidity Biosciences, Inc. reported that President and CEO Sarah Boyce disposed of equity awards in connection with the company’s merger with Novartis AG. On February 27, 2026, she transferred 474,861 shares of Common Stock (including shares issuable from previously reported restricted stock units) to the issuer under the merger terms.
Multiple “Stock Option (Right to Buy)” awards were also disposed of to the issuer pursuant to the Merger Agreement dated October 25, 2025. According to the filing, these options were exchanged for cash equal to the excess of the merger consideration of $72.00 over each award’s exercise price.
Avidity Biosciences Chief Legal Officer John B. Moriarty reported disposing of company equity in connection with a merger involving Novartis AG. On the transaction date, he surrendered 92,054 shares of Common Stock and stock options for 50,000 and 160,000 shares to the issuer.
According to the merger agreement, the Common Stock (including shares underlying previously reported restricted stock units) and options were disposed of for cash. The options were exchanged for a cash payment equal to the excess of the merger consideration of $72.00 per share over each option’s exercise price.
Avidity Biosciences Chief Scientific Officer W. Michael Flanagan disposed of his equity awards in connection with the company’s merger with Novartis. The filing shows 150,365 shares of Common Stock, including shares underlying previously reported restricted stock units, transferred to the issuer under the merger terms.
Multiple stock option grants were also disposed of to the issuer. Under the merger agreement, each reported option was exchanged for a cash payment equal to the excess of the $72.00 per share merger consideration over the option’s exercise price.
Avidity Biosciences director Troy Edward Wilson reported multiple issuer dispositions of stock options and common shares tied to the company’s merger with Novartis. On February 27, 2026, stock options covering 10,034, 13,489, and 15,000 shares were disposed of for cash under the merger terms.
The footnotes state these options were cashed out at the merger consideration of $72.00 per share minus their exercise prices. In addition, 65,091 shares of common stock held directly and 13,711 shares held indirectly through a family trust were also disposed of pursuant to the merger agreement, converting the equity into cash consideration.