Pfizer notifies top-line results from Phase III RSV vaccine trial

Pfizer's Phase III RENOIR trial reveals top-line data on its respiratory syncytial virus (RSV) vaccine, ABRYSVO, targeting RSV-related lower respiratory tract disease (LRTD) in adults aged 60 and above. The study, randomized, placebo-controlled, and double-blinded, assessed the vaccine's safety, immunogenicity, and efficacy after a single dose.

Results show 77.8% efficacy against RSV-associated LRTD after the second season, slightly lower than 88.9% after the first, suggesting lasting protection. Efficacy remains consistent for RSV A and RSV B subtypes, with rates exceeding 80% for LRTD with three or more symptoms.

Stability is noted against less severe LRTD (two or more symptoms), decreasing from 65.1% to 55.7% after the first and second seasons, respectively. Over 16.4 months, efficacy against severe RSV-associated LRTD remained at 81.5%.

Pfizer reports no new adverse events, indicating a favourable safety profile for ABRYSVO. The company plans to submit these findings to regulatory agencies and vaccine technical committees.

This follows Pfizer's Elrexfio receiving conditional approval from the European Commission for treating multiple myeloma post a Phase II trial in patients with prior multiple treatments.