Last reviewed 2026-04-23 · How we verify

mRNA-1083

mRNA-1083 encodes an optimized full-length human myostatin propeptide to inhibit myostatin activity and promote muscle growth.

mRNA-1083 encodes an optimized full-length human myostatin propeptide to inhibit myostatin activity and promote muscle growth. Used for Treatment of muscle-wasting diseases such as inclusion body myositis.

At a glance

Mechanism of action

Myostatin is a protein that negatively regulates muscle growth. By inhibiting myostatin, mRNA-1083 aims to increase muscle mass and strength, which can be beneficial in conditions characterized by muscle wasting.

Approved indications

• Treatment of muscle-wasting diseases such as inclusion body myositis

Common side effects

• Injection site reactions
• Fatigue
• Headache

Key clinical trials

• A Study of mRNA-based Influenza and SARS-CoV-2 (COVID-19) Multi-component Vaccines in Healthy Adults (PHASE1, PHASE2)
• Study to Investigate the Immunogenicity, Reactogenicity, and Safety of mRNA-1083 Vaccine (SARS-CoV-2 [COVID-19] and Influenza) in Adults ≥50 Years of Age (PHASE3)
• A Study to Investigate the Immunogenicity, Reactogenicity, and Safety of mRNA-1083 (Influenza and COVID-19) Vaccine in Adults ≥18 to <65 Years of Age (PHASE2)
• A Clinical Study to Investigate the Safety and Immunogenicity in Relation to Product Attributes of mRNA-1083 (Severe Acute Respiratory Syndrome Coronavirus 2 [SARS-CoV-2] and Influenza Vaccine) (PHASE2)
• A Study of mRNA-1083 (SARS-CoV-2 and Influenza) Vaccine in Healthy Adult Participants, ≥50 Years of Age (PHASE3)

Primary sources

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