Section 16 · Monograph
Onasemnogene abeparvovec (IV)
Reviewed Nov 2026FDA label
ZolgensmaAAV9 gene therapy
- Forms
- IV: single-dose weight-based kit
- Dose
- One-time IV infusion, 1.1 x 10^14 vg/kg (age under 2); BOXED WARNING: serious liver injury
- MOA
- Delivers a functional SMN1 gene
Black Box Warning
- Serious liver injury and acute liver failure, including fatal cases, have occurred — assess liver function (AST, ALT, bilirubin, prothrombin time) before infusion; administer systemic corticosteroid before and after infusion; monitor liver function for at least 3 months
Indications
- Treatment of pediatric patients less than 2 years of age with spinal muscular atrophy with bi-allelic SMN1 mutationsFDA-labeled
Mechanism of Action
- Non-replicating AAV9 vector delivering a functional copy of the SMN1 gene to motor neurons and other tissues
Full Dosing
Adult / usual
- One-time IV infusion over about 60 minutes, 1.1 x 10^14 vector genomes/kg (weight-based kit)
- Prednisolone-equivalent corticosteroid starting the day before infusion and continued for about 30 days then tapered, per label
- Baseline anti-AAV9 antibody testing per label
Contraindications
- None listed in labeling
Drug Interactions
- Live vaccine timing should be reviewed during corticosteroid therapy
- Avoid additional hepatotoxic drugs
Adverse Effects
- Elevated aminotransferases, vomiting
- Acute serious liver injury or liver failure
- Thrombocytopenia
- Thrombotic microangiopathy
- Troponin elevation (cardiac)
Monitoring Parameters
- Liver function tests weekly for the first month and until stable
- Platelet counts and troponin-I
- Infection and clinical status
Pregnancy & Lactation
- Not intended for use in pregnancy or lactation (pediatric indication)