NCPA 2024: Latest Updates on Respiratory Vaccines

With COVID-19, influenza, respiratory syncytial virus (RSV), and other viruses now circulating, the time for pharmacists to get up to date on the latest vaccine recommendations is now, said David Ha, PharmD, BCIDP, manager of infectious diseases at Stanford Health Care, in a session at the National Community Pharmacists Association 2024 Annual Convention and Expo.

Thus far this year, Ha said CDC data are showing a decent uptick in COVID-19 cases as well as rhinoviruses and adenoviruses. Although the increase of influenza and RSV cases hasn’t yet begun, Ha said it’s inevitable. The seasonal peak hospitalization burden for 2024 and 2025 is expected to be similar or slightly lower than the 2023-2024 season.¹

“But we’ve been fooled before, so just a reminder to keep on your toes with that,” Ha said. “Now or yesterday was the time to vaccinate.”

Women getting vaccines | Image credit: wavebreak3 | stock.adobe.com

COVID-19 Vaccines

The 2024-2025 formulations for COVID-19 vaccines are from the monovalent Omican JN.1 lineage of SARS-CoV and KP.2 (previously XBB), with available mRNA vaccines from Moderna and Pfizer as well as the protein-based Novavax vaccine. Ha noted that around 80% of US adults receive their COVID-19 vaccine from pharmacies, highlighting the importance—as well as the responsibility—of community pharmacies.¹

“Vaccination rates have declined, as I’m sure you’re aware, in the past years, with data from earlier this year suggesting that not more than maybe one-third of patients or less are up to date with their COVID-19 vaccinations,” Ha said.

Across all age groups, the 2023-2024 vaccines were effective against infection, hospitalization, and particularly against emergency department or urgent care visits. Efficacy of the 2023-2024 vaccines persisted for at least 6 months post-vaccination and the 2024-2025 vaccines are expected to be similar.¹

Safety data have shown similar adverse reactions to previous seasons. Guillain-Barre syndrome has been seen in recipients of the Pfizer vaccine who are 65 years of age or older, with 4.1 cases per million. Ha said it is unclear if this is associated with the vaccine or by chance. Ischemic stroke could be possible among recipients of the Pfizer or Moderna vaccines who are 50 to 64 years of age, or recipients of the Moderna vaccine who are 65 years or older, although this is inconsistent across age groups.¹

Importantly, Ha said the CDC’s Vaccine Safety Datalink has found no signal for myocarditis or pericarditis in males 12 to 39 years of age who receive a COVID-19 vaccine, which has previously been a concern.² However, this may be limited by low vaccine uptake in this patient population.

The CDC Advisory Committee on Immunization Practices (ACIP) advises 1 dose of the 2024-2025 mRNA vaccines for anyone 5 years of age or older, and the Novavax vaccine is an option for patients 12 years and older. A single dose of mRNA vaccine is recommended for anyone regardless of previous vaccination, or 3 doses for patients who are moderately to severely immunocompromised. For those not previously vaccinated, 2 doses of the Novavax (3+ weeks apart) is recommended.¹

There were some new updates to the ACIP recommendations ahead of the 2024-2025 season. In particular, a second dose is now recommended for those 65 years or older, ideally 6 months (2 minimum) from the initial or prior dose. A second dose is also recommended for anyone 6 months and older with moderate to severe immunocompromise.¹

“We did continue to see a waning period of about 4 to 6 months in immunity, which is problematic for our more high-risk groups, particularly those that are 65 years and older and those that are moderately to severely immunocompromised,” Ha said. “Because those 2 groups represent a disproportionate amount of the hospitalizations and severe disease, we want additional protection for these folks.”

Ideally, ACIP recommends the use of the same manufacturer for a second vaccine. However, the 2 mRNA vaccines may be used interchangeably if the same one is unavailable. For patients who receive the Novavax vaccine, the initial 2-dose series should be the same, but if it has been 8 or more weeks since the first dose, an mRNA vaccine can be substituted if Novavax is unavailable.¹

Ha also pointed out that self-attestation of moderate to severe immunocompromise is sufficient and specific documentation is not required. This also goes for RSV vaccination in older adults, which Ha discussed later.

“What I would say is the time is now to vaccinate against COVID-19,” Ha concluded.

Influenza

Although influenza vaccines did not have major ACIP updates this year, there was a notable change to the formulations. Ha said the new formulation is trivalent as opposed to previous quadrivalent formulations, with the influenza B/Yamagata strain removed because no cases have been detected since 2020 due to COVID-19 interventions. Instead, the 2024-2025 strains are A/H1N1 (Victoria), A/H3N2, and B/Austria (a Victoria-like lineage).¹

The ACIP recommends routine influenza vaccination for anyone 6 months of age or older, and those 65 years and older should preferentially receive a high-dose adjuvanted or recombinant vaccine such as Fluzone High-Dose, Fluad, or Flublok. Recipients of solid organ transplants may also receive one of these options.¹

“The data are very convincing that these vaccines do much better than the standard dose vaccines for solid organ transplant recipients,” Ha said. “I would love to see this recommendation extended to all immunocompromised patients by ACIP in the future.”

One notable update for the 2025-2026 season will be the planned availability of Flumist at-home immunization option, offering patients a new, more convenient way to reap the benefits of influenza vaccination.³ Ha said this may be especially helpful for children.

Although avian influenza A (H5N1), commonly called the bird flu, is not relevant to immunizations, Ha said patients may have questions. Thus far it has affected 324 farms in 14 states, with 31 human cases as of October 18. All of these had contact with animals and had mild disease, and there has been no human-to-human transmission or markers of antiviral resistance.¹

RSV

Ha focused primarily on RSV vaccination in older adults, saying it is at least as important as COVID-19 and influenza vaccination, despite lower public awareness. In particular, those who are older, who live in a long-term care residence, and those with cardiopulmonary conditions are particularly at high risk for severe RSV.¹

“We see RSV routinely and it is a very challenging disease to manage,” Ha said. “It can cause more severe disease than influenza and more severe disease than COVID-19. RSV vaccination is at least as important as COVID-19 and it should be considered standard for those whom it is indicated for.”

The RSV vaccines are highly effective with quite a bit of durability, highlighted by the lack of re-vaccination recommendations, although Ha said questions do remain about this. Some decline in efficacy is seen from season to season (from around 89% to 78%), but data show that efficacy persists for up to 3 seasons.¹

Routine RSV vaccination is recommended by the ACIP for anyone 75 years and older who is unvaccinated. For those aged 60 to 74 who are unvaccinated, routine vaccination is recommended if they are at high risk for severe disease. No repeat vaccine is indicated for those who were previously vaccinated.¹

Like COVID-19, Ha said self-attestation is sufficient evidence for the presence of risk factors, and RSV vaccination should not be denied due to lack of documentation. There are no formal recommendations regarding timing of the vaccine, although between August and October is recommended for maximal benefit. Importantly, Ha noted that healthy individuals 60 to 74 years of age are no longer covered in the CDC recommendations for RSV vaccines.

Pneumococcal

Finally, Ha touched briefly on pneumococcal vaccination. Capvaxive (Merck) is the newest pneumococcal vaccine, showing improved coverage of serotypes causing invasive pneumococcal disease, although it does not cover serogroup 4.¹

Most recently, the ACIP voted 14:1 to lower the routine vaccination age from 65 to 50, widening the population eligible for this vaccine. The CDC now recommends the 20-valent pneumococcal conjugate vaccine (Prevnar 20; Pfizer) and the pneumococcal 21-valent conjugate vaccine (Capvaxive; Merck).⁴

Individuals aged 19 to 49 who have certain underlying conditions or risk factors may also be eligible for pneumococcal vaccination. Ha noted that for those aged 19 to 49 who received PCV13 but not PPSV23, ACIP prefers the series with PCV20 or PCV21 rather than finishing with PPSV23.¹

“While the complexity of these recommendations may be annoying, these are actually really welcome changes,” Ha concluded. “You can see some of the other vaccines that are in developmental phases, [and] these newer vaccines are really targeting the changes in pneumococcal disease epidemiology, which is really what we need. So these changing recommendations are really part of the growing pains of all of this.”

REFERENCES

1. Ha D. Inhale, Exhale, Immunize: The Latest in Respiratory Vaccines. Presented at: National Community Pharmacists Association 2024 Annual Convention and Expo. October 26, 2024.

2. Abraham N, Spruin S, Rossi T, et al. Myocarditis and/or pericarditis risk after mRNA COVID-19 vaccination: A Canadian head to head comparison of BNT162b2 and mRNA-1273 vaccines. Vaccine. 2022;40(32):4663-4671. doi:10.1016/j.vaccine.2022.05.048

3. Antrim A. FDA Approves First At-Home Nasal Spray Flu Vaccine. Pharmacy Times. September 20, 2024. Accessed October 26, 2024. https://www.pharmacytimes.com/view/fda-approves-first-at-home-nasal-spray-flu-vaccine

4. Gallagher A. ACIP Lowers Pneumococcal Vaccination Recommendation to Age 50. Pharmacy Times. October 24, 2024. Accessed October 26, 2024. https://www.pharmacytimes.com/view/acip-lowers-pneumococcal-vaccination-recommendation-to-age-50