APhA 2025: Navigating Current RSV Vaccination Guidelines and Recommendations

Respiratory syncytial virus (RSV) has become an increasingly important target for immunization, particularly as it affects vulnerable populations such as older adults and infants. Jeff A. Goad, PharmD, MPH, a professor of pharmacy practice at Chapman University School of Pharmacy in Irvine, California, provided an in-depth discussion on the current state of RSV vaccine guidelines, outlining the options available, recommendations for administration, and key considerations for each of the available RSV vaccines at the 2025 American Pharmacists Association (APhA) Annual Meeting & Exposition in Nashville, Tennessee.

RSV is a negative-strand RNA virus belonging to the Pneumoviridae family, according to Goad. It primarily affects the respiratory system and is a leading cause of hospitalizations among infants and older adults. The most critical component for vaccine targeting is the fusion (F) protein, as it plays a key role in viral entry into host cells. Researchers have developed vaccines that focus on the pre-fusion conformation of this protein, hence the common designation of "PreF" in the nomenclature. Targeting this stage enhances the immune response and improves vaccine efficacy, Goad explained.

Currently, there are 3 vaccines available for RSV:

• RSVPreF3 (Arexvy; GlaxoSmithKline): an adjuvanted protein-based vaccine
• RSVpreF (Abrysvo; Pfizer): an unadjuvanted, bivalent protein-based vaccine
• mRNA-1345 (mRESVIA; Moderna): an mRNA-based vaccine

When looking at the indications and recommendations from the CDC and the FDA, there are some important factors to consider for each vaccine.

“Now, if we look across the FDA’s indications—the FDA makes indications, the CDC makes recommendations—they're different. Now the peer standard is CDC. Sometimes the FDA doesn’t like that, but the CDC is the peer standard,” Goad said during the APhA presentation. “If we look at FDA’s approved indications, we have, for example, for the RSVPreF3, everyone over 60 should get a dose. We know that. Now, does it delineate for 75 or older or high risk patients? That's not the FDA’s job. FDA does safety and efficacy. That's how they approve vaccines and medications. The CDC adds some more nuance through their recommendations.”

An illustration of the respiratory syncytial virus. Image Credit: © Bounheng - stock.adobe.com

The FDA has approved RSVPreF3 for individuals aged 60 and older, and RSVPreF for those aged 18 to 59 who are at increased risk for lower respiratory tract disease (LRTD) caused by RSV. RSVPreF is also the only RSV vaccine approved for pregnant individuals at 32 through 36 weeks of gestation to protect infants from RSV.

“Now, if you've been watching the CDC and what's been going on, they missed the meeting in February [2025]. Seriously, it was canceled. So that's when they were supposed to consider these new age ranges that the FDA has approved,” Goad said. “So currently, there is no CDC recommendation for anyone less than 60 years of age, other than in pregnancy.”

For older adults, the CDC has recently refined its recommendations. Individuals aged 75 and older are universally recommended to receive the RSV vaccine. For those aged 60 to 74, the recommendation is based on increased risk due to underlying conditions such as chronic cardiovascular disease; chronic lung or respiratory disease; end-stage renal disease or dependence on hemodialysis or other renal replacement therapy; diabetes complicated by chronic kidney disease, neuropathy, retinopathy, or other end-organ damage, or requiring treatment with insulin or sodium-glucose cotransporter-2 inhibitors; neurologic or neuromuscular conditions causing impaired airway clearance or respiratory muscle weakness; chronic liver disease; chronic hematologic conditions; severe obesity (body mass index ≥40 kg/m²); moderate or severe immune compromise; residence in a nursing home; and other chronic medical conditions or risk factors that a health care provider determines would increase the risk for severe disease due to viral respiratory infection.

According to Goad, the goal is to ensure targeted protection for those at highest risk while maintaining cost-effectiveness. Given the potential severity of RSV in older adults, clinicians and pharmacists must assess risk factors comprehensively when making vaccination recommendations.

In infants, RSV vaccination strategies differ. Maternal vaccination between 32 and 36 weeks gestation provides passive immunity to the newborn, reducing the likelihood of severe RSV infection in the first months of life. If maternal vaccination is not possible, nirsevimab (Beyfortus; AstraZeneca and Sanofi), a monoclonal antibody, is used to protect infants from RSV-related complications. Notably, RSV vaccines themselves are not administered directly to infants. Instead, the strategy relies on maternal antibodies and monoclonal antibodies to provide early protection. This approach aligns with evidence showing that infants younger than 6 months are at the highest risk of severe outcomes from RSV.

“Now for pregnant individuals, remember, 32 to 36 weeks gestation is different than Tdap vaccines. Tdap goes under 27 weeks, but for RSVpreF and only this RSV vaccine, that's where you want to target getting the vaccine to patients, so that in anticipation of RSV season, a baby's born, and they'll have protection during the season,” Goad said.

Regarding vaccine timing, RSV vaccines should ideally be administered between August and October to align protection with the peak RSV season, which occurs from December to February in the Northern Hemisphere. Given that vaccine-induced immunity wanes over time, proper timing is crucial for maximizing protection during the highest-risk months. This seasonal approach ensures that individuals are optimally protected when RSV transmission is at its peak.

A pregnant woman is vaccinated. Image Credit: © adipurnatama - stock.adobe.com

“Now could disease occur at any time during the year? Absolutely. But we know that the peak is around December to February. So, if we're trying to time the vaccine, which we know, like all vaccines, immune protection begins to decay after you give it and doesn't go up anymore; it just goes down after that. So, we're trying to maximize that immunity right after vaccination,” Goad said. “The recommendation looks very similar for pregnancy as well. But again, we're trying to maximize that 30 to 36 weeks to get them vaccinated, but we end vaccination for pregnant individuals in January.”

The shift in CDC recommendations from 2023 to 2024 highlights the complexities of implementing RSV vaccination. In 2023, shared clinical decision-making was recommended for adults over 60, requiring individualized discussions between health care professionals and patients. However, this approach proved difficult to implement on a large scale. The updated 2024 recommendation simplifies administration by making age 75 the universal threshold for vaccination while maintaining risk-based recommendations for those aged 60 to 74. This change aims to streamline decision-making and improve vaccine uptake in high-risk populations.

“Shared clinical decision making… is hard to implement because, unlike a recommendation, you can't target people by disease states or by age, you just have to have a conversation,” Goad said. “You identify a patient you think would benefit from the vaccine, you have a conversation with them, and they decide to get a vaccine. This is very hard on a systems level to implement.”

Vaccine efficacy has been demonstrated in clinical trials, with RSV vaccines showing 67% to 86% efficacy in preventing symptomatic infection and severe disease. Real-world effectiveness data are emerging, with Medicare and other databases reporting 72% to 83% effectiveness in preventing RSV-related complications, including hospitalizations.

“Efficacy is determined in randomized controlled clinical trials, while effectiveness is determined in real-world settings,” Goad said. “We do have some real world data now, although it’s limited because the vaccines are new, but we don't have effectiveness data for the mRNA RSV vaccine, because it's way too new [as it was approved on May 31, 2024].”

However, durability remains a key question. Current data indicate peak efficacy within the first 4 months post-vaccination, with protective effects persisting beyond 1 year. Long-term data will help determine whether additional doses will be required in the future and whether RSV vaccines should be administered annually, similar to influenza vaccines.

“What CDC is waiting for is even longer term data before they make a decision on whether you need another dose, and if so, when,” Goad said. “If I were looking at my crystal ball, I would say the RSV vaccine will probably not remain a 1-dose vaccine. So, when you're talking to patients, I would recommend saying, ‘The recommendation now is that you get 1 dose,’ to leave the door open in case the recommendation changes.”

Vaccine safety remains a priority, and rigorous surveillance systems are in place to detect potential adverse events. One safety signal detected for the protein-based RSV vaccines is an increased risk of Guillain-Barré Syndrome (GBS), a rare neurological disorder. However, GBS is also associated with other vaccines, such as influenza, COVID-19, and shingles vaccines, as well as with infections like Campylobacter jejuni. The FDA and CDC continue to monitor this signal to determine its significance in relation to RSV vaccination.

“[For vaccines,] 42 days is that critical time period that the FDA monitors for safety signals. We can assume that if something occurs within 42 days, looking at the biologic basis and causality, we're more likely to associate it with the disease. Anything beyond 42 days is unlikely to be related to a vaccine. So that's the FDA standard that CDC also uses,” Goad said. “Still compared to other vaccines and compared to Campylobacter jejuni, GBS is less common for RSV, but it's a safety signal and the FDA advises to look for GBS in patients following vaccination. But we should get an update on safety data for the vaccine to see if the signal still holds true as we have more and more shots given. So this is an ongoing issue that we're watching.”

Coadministration of RSV vaccines with other recommended vaccines is encouraged to ensure broader protection against preventable diseases. Studies indicate that RSV vaccines can be given alongside influenza and COVID-19 vaccines without interference in immune response. This approach is particularly beneficial for older adults, who often receive multiple vaccines during the fall season. Pharmacists and health care providers play a key role in ensuring vaccine uptake, as most RSV vaccines are administered in community pharmacies rather than medical clinics.

“As the pharmacist, you are busy,” Goad said. “IQVIA looked at data from EHRs and from community pharmacies to determine doses administered by pharmacy… We can see that most vaccine is given and administered in community pharmacies—the vast majority. In fact, it has not changed since when the vaccine was initially released back in 2024 when we started measuring this, and into 2025 this has not changed.”

REFERENCE

Goad JA. The RSV Rundown: Expert Reports on Current Insights and Vaccine Recommendations. Presented at: APhA Annual Meeting & Exposition; Nashville, Tennessee; March 21-24, 2025.