What the label lists and what reports show
Onasemnogene abeparvovec side effects
Onasemnogene abeparvovec's FDA label: “The most common adverse reactions (incidence ≥ 5%) were elevated aminotransferases and vomiting.” FAERS holds 2,272 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is pyrexia (535 reports).
- No generic listed
- Boxed warning
Check it at the source: the onasemnogene abeparvovec FDA label on DailyMed (effective June 16, 2026); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most common adverse reactions (incidence ≥ 5%) were elevated aminotransferases and vomiting.
Table 2: Adverse Reactions and ALT Increases* Following Treatment With ZOLGENSMA
| Adverse reactions | Patients n = 44 (3.0-8.4 kg) n (%) Abbreviations: ULN, upper limit of normal; ALT, alanine aminotransferase. *Laboratory… |
|---|---|
| Elevated aminotransferases | 12 (27%) |
| ALT > 3 X ULN | 7 (16%) |
| ALT > 20 X ULN | 4 (9%) |
| Vomiting | 3 (7%) |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe most common adverse reactions (incidence ≥ 5%) were elevated aminotransferases and vomiting. The most common adverse reactions (incidence ≥ 5%) were elevated aminotransferases and vomiting. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Novartis Gene Therapies at 1-833-828-3947 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another product and may not reflect the rates observed in practice. The safety data described in this section reflect exposure to ZOLGENSMA in five clinical studies enrolling a total of 68 patients. This includes four prospective open-label clinical trials [NCT03306277 (Study 1), NCT02122952 (Study 2), NCT03505099, NCT04851873 (Study 3)], and one observational long-term follow-up study [NCT03421977]. The patient population in NCT03306277, NCT03505099, and NCT02122952 ranged in age from 0.3 months to 7.9 months at the time of infusion (median age, 3.3 months), with weight range from 3.0 kg to 8.4 kg (median weight, 5.5 kg) [see Clinical Studies ( 14 )]. …
Source: FDA drug label, Novartis Innovative Technologies Inc., effective June 16, 2026 (SPL set 68cd4f06-70e1-40d8-bedb-609ec0afa471), via openFDA; the full label on DailyMed
What do FAERS reports show?
2,272 reports list onasemnogene abeparvovec among the medicines taken, each a report of something that happened, not proof the medicine caused it; 157 are coded as a death and 726 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 23 reactions below, 4 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Onasemnogene abeparvovec: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions