Avidity Biosciences (RNA) investor relations material

Executive summary

• Ajax Acquisition Sub, Inc., an indirect Novartis subsidiary, will merge with Avidity Biosciences, making Avidity an indirect wholly owned subsidiary of Novartis, subject to terms in the Merger Agreement dated October 25, 2025.

• Prior to the merger, Avidity will reorganize, transferring early-stage precision cardiology programs and certain collaborations to SpinCo (Atrium Therapeutics, Inc.), which will be spun off or sold.

• SpinCo shares will be distributed to Avidity stockholders at a 1:10 ratio or sold to a third party, with Avidity retaining no interest in SpinCo post-transaction.

• The transactions are subject to regulatory and shareholder approvals, with forward-looking statements highlighting potential risks, uncertainties, and the need for business continuity.

• Stephen Moran will be appointed Managing Director of Avidity post-closing, with a focus on maintaining Avidity’s unique culture and scientific excellence during the transition.

Voting matters and shareholder proposals

• A special meeting will be convened for Avidity stockholders to vote on the merger and spin-off transactions, with proxy materials to be provided in advance.

Board of directors and corporate governance

• Information on the interests of directors and executive officers in the transactions will be disclosed in the definitive proxy statement.

• Changes in beneficial ownership by directors and officers will be reflected in SEC filings as required.