This summer, GSK cut its yearly vaccine sales projection on the back of a narrowed recommendation for adult respiratory syncytial virus (RSV) vaccines from the Centers for Disease Control and Prevention. With sales of its flagship shingles vaccine Shingrix separately faltering, new data on co-administration of the two adult vaccines could provide a new way for the company to promote the jabs.
The company studied co-administration of its RSV vaccine Arexvy and Shingrix in a phase 3 study of 530 adults age 50 years and older. When the shots were given during the same doctor's visit, the company recorded non-inferior immune responses compared with separate administration of the shots during different doctor's visits.
Those who received the vaccines separately took Shingrix on the first visit and went back for their first dose of Arexvy on day 31.
Both groups experienced the same adverse events related to vaccine administration such as pain at the injection site, fatigue and muscle pain. The duration of those events were “comparable” across both trial groups, GSK reported.
“Adult immunization offers immense individual and societal benefits and yet, vaccination rates for adults are often inadequate,” the company’s vice president of scientific affairs and public health, Len Friedland, M.D., said in a press release. “With our co-administration studies, GSK is using its science and technology to help remove barriers to adult immunization, by potentially reducing the number of visits to the healthcare offices and pharmacies and ultimately help to get ahead of RSV and shingles.”
GSK will use the results to support regulatory submissions with the FDA, the European Medicines Agency and other healthcare regulators, it said.
Both RSV and shingles are common viruses that present major health risks to older adults, especially for those who are immunocompromised or have certain underlying health conditions.
GSK’s Shingrix has been the only FDA-approved shingles vaccine since Merck stopped selling its option in 2020. Arexvy first hit the scene last year along with Pfizer’s rival Abrysvo.
When the RSV vaccines debuted, they were both recommended for adults 60 and older. This year, the CDC has changed its recommendation to a single lifetime dose for those age 75 and older and for those in the 60-74 age group who have underlying conditions that leave them susceptible to severe disease.
That move shrank the predicted U.S. RSV vaccine market for 2024 to $2.2 billion, down from last year’s $2.4 billion, according to healthcare analytics company Airfinity. By the end of the decade, the annual market value could dwindle to $1.7 billion, Airfinity forecasts.
In July, GSK slightly reduced its yearly vaccine sales projection, a move it attributed to the revised CDC recommendations.
During the second quarter, Shingrix sales separately declined by 5.5% to 832 million pounds sterling ($1.07 billion). And despite the adjustment of expectations in RSV, the company expects that its offering will beat its rivals in market share—just as it did last year.