Description
Background: Three single dose respiratory syncytial virus (RSV) vaccines are marketed in the U.S.: Arexvy (GSK), Abrysvo (Pfizer), and mRESVIA (Moderna), with only Abrysvo approved for the use during pregnancy. Arexvy is indicated for adults 50+ while Abrysvo and mRESVIA are approved for adults aged 18 years. This study examined post-marketing adverse event (AE) reports with RSV vaccines and detected reporting risk signals of administration-related errors. Methods: Using the U.S. Vaccine Adverse Event Reporting System data in 1/1/2023-12/25/2025, we identified AE reports related to RSV vaccines. Frequencies and percentages of patient age, sex, vaccination facility, and outcomes (i.e., seriousness, hospitalizations, etc.) were summarized by RSV vaccine brand. The top 15 most frequently reported AEs and top 10 most frequently reported vaccine administration errors were examined for Arexvy and Abrysvo. Disproportionality analyses (reporting odds ratio and 95% confidence intervals) were conducted to detect disproportionate reporting risk signals of vaccine administration errors. All analyses were conducted using SAS version 9.4. Results: Among a total of 8,365 AE reports linked to RSV vaccines, most were related to Arexvy (68.2%) and Abrysvo (29.9%). Although not indicated, 4.2% of Arexvy AE reports (n=244) were from individuals <50 years old and 6.6% of Arexvy reports were related to the AE of Exposure during pregnancy (n=375). In addition, extra dose administered was among the top three most reported AEs for the entire sample and among different age groups (50-74 and 75+) and the most reported AE across all vaccination settings (pharmacy/stores and others). Both Arexvy and Abrysvo exhibited significant signals for vaccine administration errors such as extra dose administered, exposure during pregnancy, and product administered to patient of inappropriate age. Conclusion: Findings indicate potential misuse of Arexvy during pregnancy and excess dose for both Arexvy and Abrysvo, which highlight potential gaps in healthcare provider education and vaccine record retrieval.
Publication Info
2026.