Following the recent news that the FDA has recommended an additional Phase III trial for Novavax’s vaccine to prevent medically significant RSV disease in infants, Paul Jeng, Senior Pharma Analyst at GlobalData, a leading data and analytics company, offers his perspective:

“After a string of late-stage clinical disappointments in trials of both elderly adults and pregnant women, Novavax is now at risk of losing its first-to-market advantage for ResVax as a vaccine against serious RSV infections. An additional Phase III trial as requested by the FDA will have to be conducted over a period of at least two annual RSV seasons. With the delay in US launch, Novavax faces increased pressure from competitors such as GSK, which has two clinical-stage RSV products in its pipeline, including a Phase I/II vaccine in development for prophylaxis in a maternal population.

“RSV remains a massive, relatively untapped market with no new preventative or therapeutic products in around two decades. According to GlobalData analysis, over 2.5 million women in the US could be eligible to receive a maternal RSV vaccine each year, depending on stage of pregnancy and likelihood of giving birth during or around the RSV season.

“Moreover, AstraZeneca and Sanofi’s monoclonal antibody MEDI8897 continues to make headway as single-dose passive prophylaxis for young infants entering their first RSV season. With the recent announcement of additional Phase III testing for MEDI8897, the product may sequester market share from ResVax in the US and Europe as early as 2023, particularly in countries like Italy with relatively unfavorable views of vaccination during pregnancy.”