Pharmacists Play Key Role in Selecting Best RSV Vaccine for Older Adults

Respiratory syncytial virus (RSV) is a leading cause of seasonal respiratory illness epidemics in the United States.¹ RSV is particularly dangerous for¹:

• Adults 65 years or older, with higher risks for individuals with medical frailty and residents who are in long-term care facilities
• Immunocompromised individuals, including transplant recipients and those on immunosuppressive medications
• Individuals with chronic obstructive pulmonary disease, asthma, or heart failure

Image credit: KatMoy | stock.adobe.com

In May 2023, the FDA approved 2 vaccines—Arexvy (GSK) and Abrysvo (Pfizer Inc)—for preventing RSV-associated lower respiratory tract disease (LRTD) in adults 60 years or older.^2,3 Additionally, on May 31, 2024, the FDA approved mRNA-1345 (mRESVIA) from Moderna for the same purpose.⁴

To prevent RSV infection, the CDC recommends that adults 60 years or older should receive a single dose of an RSV vaccine through shared clinical decision-making, which entails discussions between health care providers and patients to determine the vaccine’s benefits. Adults who are at higher risk for severe RSV include those in nursing homes and individuals with chronic health conditions, frailty, or other factors that increase their risk of respiratory illness.⁵

Arexvy

Arexvy, the first FDA-approved RSV vaccine for adults, is a single-dose intramuscular injection developed by GSK.⁶ On June 7, the FDA approved Arexvy for use in adults 50 to 59 years of age with increased risk.⁷ It contains a key protein from RSV called a prefusion F glycoprotein (RSVPreF3) and an adjuvant called AS01E, which helps boost the immune response.²

The original approval was based on findings from the pivotal phase 3 AReSVi-006 clinical trial (NCT04886596), which included 24,966 participants who were randomly assigned 1:1 to receive either the vaccine or placebo. Over a median follow-up of 6.7 months, there were 7 cases (1 per 1000 participant-years) of reverse transcriptase polymerase chain reaction–confirmed RSV-related LRTD in the vaccine group compared with 40 cases (5.8 per 1000 participant-years) in the placebo group.⁸

These results demonstrate that Arexvy was highly effective in preventing LRTD in adults 60 years or older. During the first RSV season after vaccination, a single dose was 82.6% effective in protecting recipients against LRTD (96.95% CI, 57.9%-94.1%).¹ This effectiveness waned somewhat in the second season, offering 56.1% protection (95% CI, 28.2%-74.4%).¹

According to the study results, Arexvy was more reactogenic than the placebo, but most adverse events (AEs) were transient and had mild to moderate severity. There were similar incidences of serious AEs and potential immune-mediated diseases in both treatment arms.⁸

Abrysvo

Pfizer’s Abrysvo, the second FDA-approved RSV vaccine for adults 60 years or older, arrived on the scene in May 2023.⁹ Unlike Arexvy, Abrysvo is a bivalent vaccine, meaning it targets both RSV A and B strains using 2 prefusion F proteins.³

This approval was based on findings from the pivotal phase 3 RENOIR trial (NCT05035212) in adults 60 years or older. The study enrolled approximately 36,000 participants. The primary end point was vaccine efficacy against RSV-associated LRTD with at least 2 or 3 signs or symptoms, and the secondary end point was vaccine efficacy against RSV-associated acute respiratory illness.¹⁰

The results showed Abrysvo to be highly effective in preventing LRTD, with an initial efficacy of 88.9% (98% CI, 53.6%-98.7%) during the first RSV season.¹ This protection remained strong during the partial second season, offering 78.6% efficacy (98% CI, 23.2%-96.1%).¹ According to the study results, 9% of vaccine recipients and 8.5% of placebo recipients reported AEs that occurred up to 1 month after injection. The most commonly reported AEs were in the categories of infections and infestations; respiratory, thoracic, and mediastinal disorders; and cough.¹⁰

mRESVIA

Moderna’s mRESVIA (mRNA-1345), the third RSV vaccine for adults 60 years or older, was approved by the FDA on May 31, 2024, based on findings from the ConquerRSV trial (NCT05127434). This randomized, double-blinded study enrolled approximately 37,000 participants from 22 countries.⁴

The 2 primary efficacy end points were the prevention of RSV-associated LRTD with at least 2 signs or symptoms and with at least 3 signs or symptoms. A key secondary efficacy end point was the prevention of RSV-associated acute respiratory disease.¹¹ Vaccine efficacy was 83.7% (95.88% CI, 66%-92.2%) against RSV-associated LRTD with at least 2 signs or symptoms, and 82.4% (96.36% CI, 34.8%-95.3%) against the disease with at least 3 signs or symptoms. Vaccine efficacy was 68.4% (95% CI, 50.9%-79.7%) against RSV-associated acute respiratory disease.¹¹

Individuals in the mRNA-1345 group experienced more expected local adverse reactions (58.7% vs 16.2% in the placebo group) and systemic reactions (47.7% vs 32.9%).¹¹

The Pharmacist’s Role in RSV Vaccination

With their accessibility and their vast medication and vaccine expertise, pharmacists have a sizable role to play in the battle against RSV and promoting immunity in their communities. Nine in 10 Americans live within 5 miles of a pharmacy, and half of all Americans live within 1 mile of one.¹² Furthermore, pharmacies are often open for longer hours and more days per week than primary care providers, and patients visit their pharmacists during the year 12 times more often than their physician.¹⁴

In addition to administering vaccines, pharmacists can also answer potential questions about RSV vaccines, address patient concerns, and ensure a safe and smooth vaccination process.

References

1. Melgar M, Britton A, Roper LE, et al. Use of respiratory syncytial virus vaccines in older adults: recommendations of the Advisory Committee on Immunization Practices — United States, 2023. MMWR Morb Mortal Wkly Rep. 2023;72(29):793-801. doi:10.15585/mmwr.mm7229a4

2. Arexvy. Prescribing information. GSK; 2023. Accessed April 4, 2024. https://www.fda.gov/media/167805/download

3. Abrysvo. Prescribing information. Pfizer Inc; 2024. Accessed April 4, 2024. https://www.fda.gov/media/168889/download

4. Moderna receives US FDA approval for RSV vaccine mRESVIA. News release. Moderna. May 31, 2024. Accessed June 5, 2024. https://investors. modernatx.com/news/news-details/2024/Moderna-Receives-U.S.-FDA-Approval-for-RSV-Vaccine-mRESVIAR/default.aspx

5. Healthcare providers: RSV vaccination for adults 60 years of age and over. CDC. Updated March 1, 2024. Accessed April 4, 2024. https://www.cdc.gov/vaccines/vpd/rsv/hcp/older-adults.html

6. US FDA approves GSK’s Arexvy, the world’s first respiratory syncytial virus (RSV) vaccine for older adults. Press release. GSK. May 3, 2023. Accessed April 4, 2024. https://www.gsk.com/en-gb/media/press-releases/us-fdaapproves-gsk-s-arexvy-the-world-s-first-respiratory-syncytial-virus-rsvvaccine-for-older-adults/

7. US FDA approves expanded age indication for GSK’s Arexvy, the first respiratory syncytial virus (RSV) vaccine for adults aged 50-59 at increased risk. News release. GSK. June 7, 2024. Accessed June 12, 2024. https://www.gsk.com/en-gb/media/press-releases/us-fda-approves-expanded-ageindication-for-gsk-s-arexvy-the-first-rsv-vaccine-for-adults-aged-50-59-atincreased-risk/

8. Papi A, Ison MG, Langley JM, et al. Respiratory syncytial virus prefusion F protein vaccine in older adults. N Engl J Med. 2023;388(7):595-608. doi:10.1056/NEJMoa2209604

9. U.S. FDA approves Abrysvo, Pfizer’s vaccine for the prevention of respiratory syncytial virus (RSV) in older adults. Press release. Pfizer Inc. May 31, 2023. Accessed April 4, 2024. https://www.pfizer.com/news/press-release/press-release-detail/us-fda-approves-abrysvotm-pfizersvaccine-prevention

10. Walsh EE, Pérez Marc G, Zareba AM, et al. Efficacy and safety of a bivalent RSV prefusion F vaccine in older adults. N Eng J Med. 2023;388(16):1465-1477. doi:10.1056/NEJMoa2213836

11. Wilson E, Goswami J, Baqui AH, et al. Efficacy and safety of an mRNA-based RSV PreF vaccine in older adults. N Engl J Med. 2023;389:2233-2244. doi:10.1056/NEJMoa2307079

12. Nine out of 10 Americans live close to community pharmacy. News release. University of Pittsburgh Medical Center. July 28, 2022. Accessed April 4, 2024. https://www.upmc.com/media/news/072722-community-pharmacy

13. Community pharmacists’ contributions to disease management during the COVID-19 pandemic. CDC. Reviewed September 24, 2020. Accessed April 8, 2024. https://www.cdc.gov/pcd/issues/2020/20_0317.htm

14. DeMaagd G, Pugh A. Pharmacists’ expanding role in immunization practices. U.S. Pharmacist. October 18, 2023. Accessed April 8, 2024. https:// www.uspharmacist.com/article/pharmacists-expanding-role-in-immunization-practices