Last reviewed 2026-04-23 · How we verify

AVXS-101

Gene therapy for spinal muscular atrophy

Gene therapy for spinal muscular atrophy Used for Spinal muscular atrophy.

At a glance

Mechanism of action

AVXS-101 is a gene therapy that uses a viral vector to deliver a copy of the SMN1 gene to motor neurons, aiming to increase production of the survival motor neuron protein and slow disease progression.

Approved indications

• Spinal muscular atrophy

Common side effects

• Injection site reaction
• Fever
• Vomiting

Key clinical trials

• Single-Dose Gene Replacement Therapy Using for Patients With Spinal Muscular Atrophy Type 1 With One or Two SMN2 Copies (PHASE3)
• Gene Replacement Therapy Clinical Trial for Participants With Spinal Muscular Atrophy Type 1 (PHASE3)
• Pre-Symptomatic Study of Intravenous Onasemnogene Abeparvovec-xioi in Spinal Muscular Atrophy (SMA) for Patients With Multiple Copies of SMN2 (PHASE3)
• Single-Dose Gene Replacement Therapy Clinical Trial for Participants With Spinal Muscular Atrophy Type 1 (PHASE3)
• Study of Intrathecal Administration of Onasemnogene Abeparvovec-xioi for Spinal Muscular Atrophy (PHASE1)
• Long-term Follow-up of Patients With Spinal Muscular Atrophy Treated With OAV101 in Clinical Trials (PHASE3)
• Phase IIIb, Open-label, Multi-center Study to Evaluate Safety, Tolerability and Efficacy of OAV101 Administered Intrathecally to Participants With SMA Who Discontinued Treatment With Nusinersen or Risdiplam (PHASE3)
• Efficacy and Safety of Intrathecal OAV101 (AVXS-101) in Pediatric Patients With Type 2 Spinal Muscular Atrophy (SMA) (PHASE3)

Primary sources

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