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.
The Avidity Biosciences, Inc. (Nasdaq: RNA) SEC filings page on Stock Titan provides access to the company’s official regulatory disclosures as filed with the U.S. Securities and Exchange Commission. These documents offer detailed insight into how Avidity describes its Antibody Oligonucleotide Conjugates (AOCs™) platform, its late-stage neuromuscular programs in myotonic dystrophy type 1 (DM1), Duchenne muscular dystrophy (DMD) and facioscapulohumeral muscular dystrophy (FSHD), and its broader pipeline in precision cardiology and immunology.
Current reports on Form 8-K are especially important for tracking material events at Avidity. Recent 8-K filings have covered topics such as the definitive merger agreement with Novartis AG, the related Separation and Distribution Agreement for the spin-off or sale of early-stage precision cardiology programs into SpinCo, positive clinical data from the EXPLORE44® and EXPLORE44-OLE™ trials of delpacibart zotadirsen (del-zota) in DMD44, and regulatory milestones including Breakthrough Therapy designation and updated BLA submission timing for del-zota. Other 8-Ks detail public equity offerings, amendments to equity incentive plans, and executive compensation arrangements in connection with the proposed merger.
Investors and analysts can also use Avidity’s SEC filings to confirm listing information for its common stock (trading under the symbol RNA on The Nasdaq Global Market), review descriptions of SpinCo and the planned spin-off structure, and understand the conditions, termination provisions and timing expectations associated with the Novartis transaction. These filings often reference additional documents such as proxy statements, registration statements for SpinCo and financial reports that further explain Avidity’s operations, risk factors and capital structure.
On Stock Titan, Avidity’s filings are supplemented by AI-powered summaries that highlight key points from lengthy documents, helping readers quickly identify items such as clinical program updates, collaboration milestones, merger terms and changes in executive compensation. Real-time updates from EDGAR, combined with structured access to Forms 8-K and other filings, make this page a practical starting point for reviewing Avidity’s regulatory history, including material events related to its AOC platform, neuromuscular pipeline and the proposed acquisition by Novartis.
Avidity Biosciences has completed its merger with Novartis and will become a private, indirect wholly owned subsidiary of Novartis. Ajax Acquisition Sub merged into Avidity on February 27, 2026, with Avidity surviving as the subsidiary.
In a related separation, Atrium Therapeutics (SpinCo) assumed Avidity’s early-stage precision cardiology programs, including AOC 1086 and AOC 1072, and related collaboration agreements with Bristol-Myers Squibb and Eli Lilly. All other assets and liabilities remained with Avidity.
Following the merger, Avidity notified Nasdaq of its intent to delist, with trading suspension for its common stock on March 2, 2026 and plans to terminate SEC registration and reporting. All outstanding common shares were converted into the right to receive the merger consideration, and stockholders’ rights otherwise ended. Avidity’s board and executive officers resigned, replaced by the former directors and officers of the merger subsidiary, and its charter and bylaws were amended and restated in line with the merger agreement.
Avidity Biosciences stockholders approved a landmark transaction combining a sale of the company with a spin-off. At a special meeting, investors adopted the Agreement and Plan of Merger with Novartis AG and the Separation and Distribution Agreement creating Atrium Therapeutics, Inc. as a separate company. The Transactions Proposal received 123,351,048 votes for, 8,090 against, and 60,331 abstentions, with 296,100 broker non-votes, comfortably clearing the approval threshold. Stockholders also backed, on a non-binding basis, the merger-related compensation for named executive officers, with 101,383,553 votes for and 21,654,186 against. Approval of the Transactions Proposal satisfies the stockholder vote condition needed to move toward closing the merger and separation.
Avidity Biosciences is a clinical-stage RNA therapeutics company advancing a new class of Antibody Oligonucleotide Conjugates (AOCs) and planning a sale to Novartis. The company has three lead AOC programs: del-zota for Duchenne muscular dystrophy amenable to exon 44 skipping (DMD44), del-desiran for myotonic dystrophy type 1 (DM1) and del-brax for facioscapulohumeral muscular dystrophy (FSHD).
In October 2025, Avidity agreed to merge with a Novartis subsidiary, with Avidity becoming an indirect wholly owned subsidiary after closing. A pre-closing reorganization will move early-stage precision cardiology assets and certain collaborations into a separate company, SpinCo, which may be distributed to shareholders on a one-for-ten basis or sold to a third party, with net cash proceeds then distributed. The merger and related distribution are targeted to close in the first half of 2026, subject to conditions, and include a $450 million termination fee payable by Avidity in some circumstances and a $600 million reverse termination fee payable by Novartis in others.
Avidity highlights strong clinical momentum: del-zota showed substantial dystrophin restoration, creatine kinase reductions greater than 80% and functional improvements versus natural history in the EXPLORE44 program, with an FDA Breakthrough Therapy designation and a planned 2026 BLA submission for potential accelerated approval. Del-desiran is in a fully enrolled global Phase 3 HARBOR trial with a 54-week data cutoff and prior long-term data suggesting reversal of DM1 progression, while del-brax is in a Phase 1/2 FORTITUDE biomarker cohort and a global Phase 3 FORTITUDE-3 study, supported by positive dose-escalation data and regulatory alignment on accelerated and full approval pathways.
Avidity Biosciences, Inc. filed an update describing plans to briefly convene and then immediately adjourn its special meeting of stockholders originally set for February 23, 2026, reconvening on February 26, 2026 via the same virtual link.
The adjournment is intended to allow more time to satisfy conditions for the pro rata distribution of all Atrium Therapeutics, Inc. (“SpinCo”) common stock to Avidity stockholders, a required step before the previously announced merger with Novartis AG can close. The distribution is expected on February 26, 2026 and the merger closing on February 27, 2026, each subject to customary closing conditions, including stockholder approval.
Avidity’s common stock is expected to temporarily trade on the Nasdaq Global Market under the symbol “RNAM” in connection with the distribution and merger closing. The record date for the special meeting remains January 29, 2026, previously submitted proxies remain valid unless revoked, and stockholders who have not yet voted are encouraged by the company to do so.
Janus Henderson Group plc reported beneficial ownership of 6,939,503 shares of Avidity Biosciences, Inc. common stock, representing 4.6% of the class as of 12/31/2025. The shares are held across various investment advisers and their managed client portfolios.
The filing shows Janus Henderson’s asset manager subsidiaries have shared power to vote and dispose of all 6,939,503 shares, with no sole voting or dispositive power. The managed portfolios are entitled to dividends and sale proceeds, and none of them individually owns more than five percent of Avidity’s common stock.
T. Rowe Price Associates, Inc. filed Amendment No. 8 to a Schedule 13G reporting beneficial ownership of 142,888 shares of Avidity Biosciences, Inc. common stock, representing 0.1% of the class as of 12/31/2025.
The firm reports sole voting power over 140,624 shares and sole dispositive power over 142,888 shares, with no shared voting or dispositive power. It states the shares were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of Avidity Biosciences, and that its ownership is 5 percent or less of the outstanding common stock.
Avoro Capital Advisors LLC and Behzad Aghazadeh report beneficial ownership of 8,515,792 shares of Avidity Biosciences common stock, including 3,060,792 shares issuable upon exercise of pre-funded warrants. This represents 5.54% of the company’s common stock, based on 150,675,742 shares outstanding as of October 31, 2025.
The reporting persons state they hold the securities in the ordinary course of business and not for the purpose of changing or influencing control of Avidity Biosciences. Both report sole voting and dispositive power over the same 8,515,792 shares.
Wellington Management Group LLP and affiliates filed an amended Schedule 13G reporting beneficial ownership of Avidity Biosciences common stock. They report beneficial ownership of 723,118 shares, representing about 0.5% of the outstanding common stock as of the event date.
The firms report no sole voting or dispositive power, with 582,610 shares subject to shared voting power and 723,118 shares subject to shared dispositive power. The securities are held in the ordinary course of business for advisory clients, and no single client is reported to hold more than five percent of the class.
Avidity Biosciences, Inc. has set an expected record date of February 12, 2026 for a planned pro rata distribution of all issued and outstanding shares of common stock of Atrium Therapeutics, Inc. to holders of Avidity common stock as of that date.
This planned spin-off of Atrium Therapeutics, referred to as SpinCo, is tied to the previously announced proposed acquisition of Avidity by Novartis AG and the separation of Avidity’s early-stage precision cardiology programs into SpinCo. The filing emphasizes that completion and timing of these transactions depend on customary closing conditions, regulatory approvals, and Avidity stockholder approval, and highlights numerous risks that could cause actual outcomes to differ from current expectations.