The appointment of vaccine skeptic Robert F. Kennedy Jr. to lead the US Department of Health & Human Services (HSS) and some of the actions he has taken in his first months have raised regulatory uncertainty for vaccines, preventative products that already have a laborious development path and take many years to develop.
There are 14 vaccines in Phase III development for infectious disease, excluding next-generation COVID-19 vaccines, according to a scan of the vaccine R&D landscape by Scrip. Almost all of them are from the world’s four leading vaccines manufacturers – GSK, Sanofi, Pfizer and Merck & Co. – though the mRNA specialist Moderna has the single highest number of vaccines in Phase III development with four.
Many of the late-stage vaccines in development are against viruses with already commercially available vaccines available like flu, pneumonia and varicella, but some could fill voids in the market, including Pfizer and Valneva’s vaccine for Lyme disease and Moderna’s vaccines for cytomegalovirus and norovirus. (See chart below.)
As the US Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP) heads into a meeting June 25-26, the advisory group’s new working group on Lyme disease was expected to present some initial findings on epidemiology, burden and clinical manifestations, beginning preparations for a review of the new Lyme disease vaccine. The first Phase III data from Pfizer/Valneva’s Phase III VALOR trial are expected at the end of the year.
However, Kennedy’s decision to fire all 17 of the ACIP experts two weeks before the June meeting, and the backgrounds of the replacements, have raised questions about how prepared the new advisors will be to jump in on the June agenda.
Longer-term, vaccine developers are working on a wide array of vaccines relying on various mechanisms. There are around 30 vaccines in Phase II development across the industry, including several that could be the first available vaccines for conditions, like GSK’s vaccines for salmonella and Shigella, Moderna’s vaccines for Epstein-Barr virus and Herpes simplex, and Pfizer’s vaccine for Clostridioides difficile (C. difficile).
Although Pfizer has a vaccine, PF-06425090, listed as being in Phase III for C. difficile, the Phase III CLOVER trial missed its primary endpoint in 2022. The company has pivoted to an updated formulation, which is in Phase II, and will use the data from that trial to determine the next steps for the program.