Atlanta—The less-than-universal recommendation by a CDC committee is expected to mean a considerably lower uptake of respiratory syncytial virus (RSV) vaccines by older adults.

The Advisory Committee on Immunization Practices (ACIP) voted that adults aged 65 years and older may receive a single dose of the vaccine, using shared clinical decision-making with their care providers.

The second vote said that shared clinical decision-making based on risk assessment should be used for adults aged 60 to 64 years.

In May, the FDA approved two RSV vaccines for use in adults aged 60 years and older—GSK’s vaccine Arexvy (which is a recombinant glycoprotein vaccine that contains the company’s proprietary AS01 adjuvant) and Pfizer's RSV vaccine Abrysvo (an unadjuvanted bivalent recombinant subunit vaccine that contains antigens against the A and B RSV subgroups).

Both vaccines contain 120 mcg of antigen and are given as a single IM dose.

The ACIP suggested that the decision whether or not to vaccinate an individual may be informed by the:

• Best available evidence of who may benefit
• An individual’s characteristics, values, and preferences
• The healthcare provider’s clinical discretion
• The characteristics of the vaccine being considered.

In this case, the CDC noted that adults who may be at higher risk of RSV disease include those with immune compromise, endocrine disorders (e.g., diabetes, hematologic disorders), chronic cardiovascular diseases (e.g., congestive heart failure and coronary artery disease), neurologic disorders, chronic lung diseases (e.g., chronic obstructive pulmonary disease and asthma), and kidney and liver disorders.

Living in a long-term care facility also is a risk factor, according to public health officials.

The ACIP also noted that RSV vaccination is currently approved and recommended as a single dose, and “optimally, vaccination of eligible adults should occur before the onset of increased RSV activity in the community.” The timing is unclear because the season deviated during the COVID-19 pandemic.

“Given this variability, the ideal time to start vaccinating cannot be predicted in advance of the 2023-2024 RSV season,” the CDC advised. “Providers should therefore offer RSV vaccination as soon as vaccine supply becomes available. Providers should continue to offer RSV vaccination throughout the RSV season to eligible adults who remain unvaccinated. There are insufficient data at this time to determine the need for revaccination.”

Guidance also was offered on coadministration of RSV vaccines with other vaccines, with the authors pointing out, “In accordance with General Best Practice Guidelines for Immunization, coadministration of RSV vaccines with other adult vaccines is acceptable This includes giving RSV vaccines simultaneously with seasonal influenza vaccines, COVID-19 vaccines, pneumococcal vaccines, Td/Tdap [tetanus and diphtheria/tetanus, diphtheria, and pertussis], and recombinant zoster vaccine (Shingrix).”

They cautioned, however, that data are currently limited on the immunogenicity of coadministration of RSV vaccines with other vaccines. “In general, coadministration of RSV and seasonal influenza vaccines met non-inferiority criteria for immunogenicity,” according to the report. “However, RSV and influenza antibody titers were generally somewhat lower with coadministration. Additional studies on immunogenicity of coadministration of RSV with other adult vaccines are in process.”

It added that prespecified noninferiority criteria for immune responses were met across trials, with the exception of the FluA/Darwin H3N2 strain after simultaneous administration of the RSVPreF3 vaccine (Arexvy by GSK) and the adjuvanted quadrivalent inactivated influenza vaccine. The CDC also warned that coadministration of multiple vaccines at the same visit may increase reactogenicity, noting, “Post-licensure safety monitoring of coadministration of RSV vaccines with other vaccines will further inform coadministration guidance.”

Even though they were not included in clinical trials, the ACIP says that patients with immunocompromising conditions also may receive the RSV vaccine under shared clinical decision making. “Adults with immunocompromising conditions are at risk of severe RSV-associated disease and death. They may benefit from RSV vaccination but were not included in the clinical trials so efficacy in this population is unknown. These individuals, including those receiving immunosuppressive therapy, may have a diminished immune response to RSV vaccination.”

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.

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