GSK announced that Japan’s Ministry of Health, Labour and Welfare has accepted its regulatory application to extend the use of its adjuvanted recombinant respiratory syncytial virus (RSV) vaccine, Arexvy.
Previously, Arexvy was approved in Japan for use in adults aged 60 and older and those aged 50 and older at increased risk of RSV.
The application seeks its use in adults aged 18-49 at increased risk of severe RSV disease.
GSK’s RSV vaccine includes recombinant glycoprotein F stabilised in the prefusion conformation (RSVPreF3) combined with GSK’s proprietary AS01E adjuvant.
The AS01 adjuvant system contains STIMULON QS-21, licensed from Antigenics, a subsidiary of Agenus.
RSV is a contagious virus affecting the lungs and breathing passages, and can exacerbate medical conditions, leading to severe illness, hospitalisation, and even death.
The regulatory submission is supported by positive results from an open-label Phase 3b trial (NCT06389487) evaluating the immune response and safety of GSK’s RSV vaccine in adults aged 18-49 at increased risk, compared to adults aged 60 and older.
The study involved 1,458 participants across 52 locations in six countries, including Japan.
In the trial, the vaccine showed a non-inferior immune response in adults at increased risk for RSV-LRTD due to certain underlying conditions, compared to adults aged 60 and above.
Safety and reactogenicity data were consistent with the Phase 3 programme that supported the initial approval in Japan.
GSK is the first company to seek regulatory approval for this age group in Japan.
Furthermore, the British drugmaker is continuing its efforts to expand the vaccine’s indications in other regions, including the US and Europe.
