Atrium Therapeutics (symbol: RNA), which is described in the background as Avidity Biosciences, Inc., is a biopharmaceutical company that develops and commercializes therapies for serious diseases. As such, it sells its products primarily to individuals, specifically patients who suffer from these conditions, through the healthcare system.

The major categories of customers it serves are:

• Patients with Myotonic Dystrophy Type 1
• Patients with Duchenne Muscular Dystrophy
• Patients with Facioscapulohumeral Muscular Dystrophy

Sarah Boyce, President and Chief Executive Officer

Sarah Boyce joined Avidity Biosciences as President and CEO in October 2019. She brings over 25 years of global leadership experience in the life sciences industry, having built global organizations and successfully launched innovative therapies such as Tegsedi®, Waylivra®, Soliris®, Gleevec®, and Tasigna®. Before joining Avidity, Ms. Boyce served as President and a board member of Akcea Therapeutics from April 2018 to September 2019, where she led the commercialization of the company's rare disease products. Her career includes executive roles at prominent pharmaceutical and biotech companies, including Ionis Pharmaceuticals, Forest Laboratories, Alexion Pharmaceuticals, Novartis Oncology, and Roche. Ms. Boyce has also been instrumental in Avidity's growth, leading the company through a successful Series C funding round and an IPO. She currently serves on the boards of Ligand, Inc., OmniAb, Inc., Contineum Therapeutics, Inc., and Abcuro, Inc. She holds a B.S. degree in microbiology from the University of Manchester, England.

Michael MacLean, Chief Financial and Chief Business Officer

Michael MacLean was appointed Chief Financial Officer of Avidity Biosciences in May 2020, and his role was expanded to include Chief Business Officer in April 2022. He possesses decades of industry experience, particularly in funding biotechnology companies, developing strategic plans, fostering partnerships for novel technologies, and advancing therapies in rare and orphan disease areas through commercialization. Prior to Avidity, Mr. MacLean served as Chief Financial Officer of Akcea Therapeutics, Inc., where he was responsible for building out its financial and global infrastructure. His previous experience also includes serving as Chief Financial Officer of PureTech Health, plc, and Chief Accounting Officer of Biogen Inc., where he oversaw worldwide finance operations. Mr. MacLean has been involved with companies that underwent acquisition; he was CFO of Akcea Therapeutics, which was eventually acquired, and he disposed of company equity in connection with Avidity Biosciences' merger with Novartis AG in February 2026.

Steve Hughes, MD, Chief Medical Officer

Dr. Steve Hughes joined Avidity Biosciences as Chief Medical Officer in February 2022. He brings over 20 years of experience in building and leading clinical development and medical affairs teams. Dr. Hughes has contributed to more than 50 clinical trials for over 25 drugs across various therapeutic areas, including cardiovascular, neurology, and several rare diseases. Before joining Avidity, he served as Chief Medical Officer at Arcturus Therapeutics, where he continues to act as a strategic clinical advisor. His prior positions include Chief Medical Officer at Organovo, Chief Clinical Development Officer at Ionis Pharmaceuticals, and roles at Biogen, CSL Behring, and Sanofi. Dr. Hughes is board certified in pharmaceutical medicine and earned his medical degree and an MBA from Imperial College, London.

The primary clear emerging threat for Avidity Biosciences, Inc. (RNA) is the **rapid advancement and potential market dominance of competing novel therapeutic modalities from other biopharmaceutical companies.**

This includes:

• The emergence of alternative targeted oligonucleotide delivery platforms or antibody-oligonucleotide conjugates (AOCs) from competitors that demonstrate superior efficacy, safety, or broader application for diseases such as myotonic dystrophy type 1, Duchenne Muscular Dystrophy, or facioscapulohumeral muscular dystrophy.
• Significant breakthroughs in gene therapy or gene-editing technologies (e.g., CRISPR) that could offer more durable or curative treatments for these rare monogenic diseases, potentially rendering oligonucleotide-based approaches less competitive.

The addressable markets for Avidity Biosciences, Inc.'s main products are as follows:

• AOC 1001 (Myotonic Dystrophy Type 1 - DM1): The global market for Myotonic Dystrophy Type 1 (DM1) is projected to grow from USD 1,550 million in 2024 to USD 3,204 million by 2032, exhibiting a compound annual growth rate (CAGR) of 9.5% over the forecast period. Another estimate places the global Myotonic Dystrophy Treatment Market size at US$ 874.39 Million in 2023, with a projection to reach approximately US$ 2,789.35 Million by 2033, growing at a CAGR of 12.3%. Myotonic dystrophy type 1 is estimated to affect approximately 80,000 individuals in the United States and Europe. In 2023, the United States accounted for nearly 54,068 diagnosed prevalent cases of Myotonic Dystrophy.

• AOC 1044 (Duchenne Muscular Dystrophy - DMD): The global Duchenne Muscular Dystrophy (DMD) drugs market size was estimated at USD 3.47 billion in 2023 and is projected to reach USD 9.91 billion by 2030, with a CAGR of 16.8% from 2024 to 2030. Another report estimates the global Duchenne muscular dystrophy drugs market size at USD 4.79 billion in 2025, predicted to increase to approximately USD 19.46 billion by 2034, expanding at a CAGR of 16.85% from 2025 to 2034. There are approximately 15,000 patients with DMD in the U.S. Duchenne Muscular Dystrophy affects 1 in 3,500 to 5,000 boys born worldwide. AOC 1044 specifically targets DMD mutations amenable to exon 44 skipping, which accounts for around 6% of all DMD cases in the U.S.

• AOC 1020 (Facioscapulohumeral Muscular Dystrophy - FSHD): The 7 major facioscapulohumeral muscular dystrophy markets (7MM includes the United States, EU4, and Japan) reached a value of USD 32.2 Million in 2024 and are expected to reach USD 61.4 Million by 2035, exhibiting a CAGR of 6.12% during 2025-2035. The U.S. alone represented about 45% of all FSHD cases across the 7MM in 2024. Overall, the United States accounts for the largest market share (around 80%) of the Facioscapulohumeral Muscular Dystrophy Market, when compared to EU4 and Japan. There are an estimated 45,000-87,000 patients with FSHD. In 2023, the total prevalent cases of FSHD in the 7MM were approximately 79,000. Currently, there are no available therapies that can slow, halt, or reverse the progression of muscle weakness in facioscapulohumeral muscular dystrophy.

Here are 3-5 expected drivers of future revenue growth for Avidity Biosciences, Inc. (symbol: RNA) over the next 2-3 years:

1. Advancement and Potential Commercialization of AOC 1001 (del-desiran) for Myotonic Dystrophy Type 1 (DM1): As Avidity Biosciences' lead product candidate, AOC 1001 (also known as del-desiran) is progressing through clinical development, with the global Phase 3 HARBOR trial initiated in mid-2024. Positive long-term data from earlier trials, demonstrating improvements in disease progression, support its potential. The company has received FDA Breakthrough Therapy Designation for AOC 1001 and is accelerating commercial preparations for a potential launch in rapid succession, which could contribute significantly to revenue within the next 2-3 years.
2. Clinical Progress and Market Entry of AOC 1044 (del-zota) for Duchenne Muscular Dystrophy (DMD) amenable to Exon 44 Skipping (DMD44): AOC 1044 (del-zota) has demonstrated promising results in Phase 1/2 clinical trials, including significant increases in dystrophin production. The FDA has granted Fast Track designation for AOC 1044, and the company plans to submit a Biologics License Application (BLA) by year-end 2025, with an accelerated approval pathway confirmed. This timeline positions AOC 1044 for potential market entry and revenue generation within the next 2-3 years.
3. Development and Future Launch of AOC 1020 (del-brax) for Facioscapulohumeral Muscular Dystrophy (FSHD): AOC 1020 (del-brax) has also received FDA Fast Track designation and shown positive initial data from its Phase 1/2 FORTITUDE trial, indicating reductions in disease-related gene expression and trends of functional improvement. Avidity Biosciences plans to accelerate the initiation of registrational cohorts and a global pivotal trial by mid-2025, with commercialization preparations underway, indicating a potential revenue driver in the near to medium term.
4. Broader Pipeline Expansion and Platform Versatility: Avidity Biosciences is continuously advancing its proprietary Antibody Oligonucleotide Conjugate (AOC) platform, which is designed to deliver RNA therapeutics to target tissues. Beyond its lead programs, the company is developing additional AOCs for various Duchenne muscular dystrophy mutations and expanding its pipeline into other rare neuromuscular diseases. The ongoing discovery and development of new candidates leveraging the AOC platform represent a sustained driver of future growth through new product launches or partnership milestones.
5. Strategic Collaborations and Milestone Payments: As a clinical-stage biopharmaceutical company, Avidity Biosciences generates revenue through collaborations and achieving developmental milestones with larger pharmaceutical partners. For instance, the company received a $10.0 million clinical development milestone payment from Eli Lilly and Company in the third quarter of 2025. Continued progress of its clinical programs is expected to trigger further milestone payments and potential future licensing agreements, contributing to its revenue streams.

Share Issuance

• Avidity Biosciences closed an underwritten public offering in September 2025, selling 17,250,000 shares of its common stock at $40.00 per share, which generated gross proceeds of $690.0 million.
• In February 2024, the company agreed to sell 15,224,773 shares of common stock and pre-funded warrants for 9,030,851 shares in a private placement, resulting in approximately $400 million in gross proceeds.

Inbound Investments

• Novartis AG completed the acquisition of Avidity Biosciences on February 27, 2026, in an all-cash deal valued at approximately $12 billion, with Avidity shareholders receiving $72.00 per share.
• During the third quarter of 2025, Readystate Asset Management LP acquired a new stake of 15,505 shares of Avidity Biosciences, valued at about $676,000.
• JPMorgan Chase & Co. significantly increased its stake in Avidity Biosciences by 55% in Q3 2025, holding 899,557 shares worth approximately $39.2 million.

Outbound Investments

• Prior to its acquisition by Novartis, Avidity Biosciences spun off its early-stage precision cardiology assets into a new, independent public company named Atrium Therapeutics, Inc. (now trading under symbol RNA) in February 2026.
• As part of the spin-off, Avidity distributed one share of Atrium Therapeutics common stock for every ten shares of Avidity common stock held by its shareholders.
• Atrium Therapeutics, Inc. launched with approximately $270 million in cash to advance its pipeline.

Capital Expenditures

• Avidity Biosciences' capital expenditures were $3.74 million in 2021, $2.82 million in 2022, $4.23 million in 2023, and $7.07 million in 2024.
• Expected capital expenditures for 2025 are projected to be $13 million.