GSK plc announced that the US Food and Drug Administration (FDA) has accepted a Biologics License Application (BLA) and granted Priority Review for its respiratory syncytial virus (RSV) older adult vaccine candidate.

The US FDA grants Priority Review to applications for vaccines that, if approved, would offer significant improvements in the safety or effectiveness of the treatment or prevention of serious conditions when compared to standard applications. A Priority Review designation means the US FDA’s goal is to expedite review of a BLA, reducing the review period by four months. The Prescription Drug User Fee Act date, the FDA action date for their regulatory decision, is 3 May 2023. If approved, GSK’s RSV older adult vaccine candidate has the potential to be the first vaccine available to help protect adults aged 60 years and older from lower respiratory tract disease caused by RSV infection.

Older adults are at high risk for severe disease due to age-related decline in immunity and underlying conditions. RSV can exacerbate conditions, including chronic obstructive pulmonary disease (COPD), asthma and chronic heart failure and can lead to severe outcomes, such as pneumonia, hospitalisation, and death.

The BLA is based on positive data from a prespecified interim analysis of the pivotal AReSVi-006 (Adult Respiratory Syncytial Virus) phase III trial, which showed high overall vaccine efficacy against RSV lower respiratory tract disease (LRTD) in adults aged 60 years and older. The vaccine was well tolerated with a favourable safety profile. The most frequent observed solicited adverse events were injection site pain, fatigue, myalgia, and headache. Consistent high vaccine efficacy was observed against LRTD in severe disease, adults aged 70-79 years, adults with underlying comorbidities and across RSV A and B strains.

This is the third major regulatory milestone for GSK’s RSV older adult vaccine candidate following regulatory submission acceptances by the European Medicines Agency and Japan’s Ministry of Health, Labour and Welfare. GSK’s RSV older adult vaccine candidate contains a recombinant subunit prefusion RSV F glycoprotein antigen (RSVPreF3) combined with GSK’s proprietary AS01E adjuvant. There are currently no RSV vaccines for older adults approved anywhere in the world.