No, Arexvy Is Not the First RSV Vaccine
Arexvy, developed by GSK, received FDA approval on May 3, 2023, as the second RSV vaccine for adults aged 60 and older.[1] It targets the RSV prefusion F protein to prevent lower respiratory tract disease.
What Was the First RSV Vaccine?
Abrysvo, from Pfizer, earned FDA approval one day earlier, on May 3, 2023 (via priority review), also for adults 60+ and later expanded to pregnant women for infant protection.[1][2] Both vaccines launched in the 2023-2024 respiratory season, with Arexvy following closely in availability.
How Do Arexvy and Abrysvo Compare?
| Feature | Arexvy (GSK) | Abrysvo (Pfizer) |
|---------|--------------|------------------|
| Approval Date | May 3, 2023 | May 3, 2023 (first) |
| Target Population | Adults 60+ | Adults 60+; pregnant women (32-36 weeks) |
| Efficacy (Phase 3) | 83% vs. RSV lower respiratory disease (median 2-season follow-up)[3] | 89% vs. RSV acute lower respiratory infection (1 season); 81% for infants via maternal immunization[4] |
| Dosing | Single dose | Single dose |
| U.S. Sales (2023) | ~$1.5B (leading market share) | ~$1B |
Arexvy has shown longer-duration protection in trials, but Abrysvo's maternal indication gives it a unique edge for infant protection.[3][4]
Are There Other RSV Vaccines?
- Approved: Only Arexvy and Abrysvo in the U.S. and EU for adults; Sanofi/AstraZeneca's Beyfortus (nirsevimab) is a monoclonal antibody for infants, not a vaccine.[1]
- In Development: Moderna's mRESVIA (FDA-approved May 2024, third for adults 60+); Janssen's single-dose candidate; several others in late-stage trials targeting pediatrics or high-risk groups.[2][5]
When Did RSV Vaccine Development Accelerate?
Breakthroughs in stabilizing the RSV prefusion F protein (2013 onward) enabled modern vaccines after decades of failures.[6] Pre-2023 candidates like Novavax's ResVax flopped in trials (e.g., 2016 Phase 3).[7]
Patent and Exclusivity Timelines
Arexvy's key U.S. patents (e.g., prefusion F stabilization) expire around 2035-2038; GSK has pediatric exclusivity until ~2034.[8] Abrysvo's core patents run to 2036-2040.[8] No biosimilars expected before 2030 due to complex biologics.
Sources
[1]: FDA.gov - Arexvy Approval
[2]: FDA.gov - Abrysvo Approval
[3]: NEJM - Arexvy Efficacy
[4]: NEJM - Abrysvo Efficacy
[5]: ClinicalTrials.gov - RSV Vaccines
[6]: Science - Prefusion F Discovery
[7]: NEJM - ResVax Trial
[8]: DrugPatentWatch.com - RSV Vaccines