Pfizer, BioNTech post partial win in late-stage trial for COVID/flu combo shot

Pfizer (NYSE:PFE) and BioNTech (NASDAQ:BNTX) announced Friday that a Phase 3 clinical trial for their combined mRNA vaccine against influenza and COVID-19 met only one of its two primary objectives.

The trial, which involved more than 8,000 healthy adults aged 18–64, was designed to evaluate the combined vaccine against a licensed influenza vaccine and the companies’ FDA-approved COVID-19 vaccine. The investigators then measured the participants’ antibody responses to influenza A and B strains and COVID-19.

Citing topline data, Pfizer (PFE) and BioNTech (BNTX) said that the combined vaccine did not meet the primary immunogenicity objective related to a comparable performance (non-inferiority) against the influenza B strain.

However, there were higher influenza A responses and comparable COVID-19 responses against the comparator vaccines. An ongoing safety analysis didn’t indicate safety signals for the combined shot.

Additionally, the duo updated on Pfizer’s (PFE) second-generation trivalent flu vaccine (tIRV). Citing data from people aged 18–64 who received tIRV as part of a Phase 2 trial, the companies said that the mRNA vaccine showed encouraging influenza A and B responses, including more robust influenza A responses compared to a licensed flu shot.

PFE and BNTX added that the readout didn’t show new safety signals, and data from adults 65 years of age and older would be made available later.