Pfizer Releases ABRYSVO for RSV: Top-Line Results in Immunocompromised Adults

Pfizer reported top-line interim safety and immunogenicity outcomes from Substudy B within the MONeT-RSV Immunization Study for Adults, showing that two doses of the ABRYSVO vaccine provided safety and immunogenicity in immunocompromised individuals aged 18 years and older who are at risk of developing lower respiratory tract disease (LRTD) due to RSV.

Patients with compromised immune systems are more likely to develop RSV-LRTD. Substudy B of the MONeT trial was conducted to evaluate the safety and immunogenicity of two doses of ABRYSVO, administered one month apart, in four groups of immunocompromised adults: patients with non-small cell lung cancer, patients receiving hemodialysis for end-stage renal disease (ESRD), patients with autoimmune diseases (AID) receiving active immunomodulatory therapy, and recipients of solid organ transplants.

A subgroup of 203 adult participants was included in this substudy, with approximately half of the participants between 18 and 59 years of age and the other half 60 years or older.

The side effects of ABRYSVO were mild during the trial, and the safety profile aligned with previous studies of the vaccine. A single 120 µg dose of ABRYSVO was sufficient to induce a neutralizing response against both RSV subtypes, RSV-A and RSV-B, in all cohorts and age categories in the trial, despite the company initially considering two doses. Pfizer intends to present these findings at an upcoming scientific meeting and submit them to scientific journals for peer review, as well as to regulatory authorities for review.

“Finally, a vaccine specifically designed for older adults, whose immunocompromised conditions significantly increase the risk and severity of developing RSV, has been developed. However, U.S. populations up to 59 years old remain unprotected due to the lack of available vaccines for their age group,” said Annaliesa Anderson, Senior Vice President and Chief Scientific Officer of Research and Development at Pfizer Vaccine.

These recently reported data in immunocompromised adults add to the evidence supporting the profile of ABRYSVO in high-risk adults. This analysis of a cohort of adults aged 18 to 59 years with certain chronic medical conditions was presented at the annual meeting of the Advisory Committee on Immunization Practices (ACIP) in June 2024 by Pfizer.

In this double-blinded trial, 681 subjects aged 18–59 with chronic diseases were randomized in a 2:1 ratio to receive either ABRYSVO or a placebo. The participants demonstrated an RSV-A and RSV-B neutralizing antibody response that was as effective as that observed in the Phase 3 RENOIR study for ABRYSVO, which established the vaccine’s efficacy in adults aged 60 years and above. These results corroborate data previously reported at ACIP on the high clinical efficacy of ABRYSVO against lower respiratory tract illness in the adult population aged 60 and above, which included a significant number of immunocompromised patients.

The post Pfizer Releases ABRYSVO for RSV: Top-Line Results in Immunocompromised Adults appeared first on LifeSci Voice.