Squaring off against Pfizer in the next-gen pneumococcal vaccine field, Merck has posted two more positive phase 3 trials and now says it's planning an FDA filing yet this year. That timing matches rival Pfizer's, setting up a market duel with billions likely on the line.
In one study in healthy adults age 50 and older, Merck’s 15-valent pneumoccocal vaccine candidate matched the efficacy for Pfizer’s Prevnar 13 for the 13 serotypes covered by the best-selling Pfizer shot. Further, the vaccine bested the marketed shot against serotypes 22F and 33F, which Merck says currently cause 13% of invasive pneumococcal disease cases in U.S. adults 65 and older, plus between 7% and 12% of the cases in Europe.
The candidate, V114, also beat Prevnar 13 at protecting against serotype 3, which is a leading cause of invasive pneumococcal disease worldwide. The investigators tracked immunogenicity by opsonophagocytic activity, which is a measure of vaccine-induced functional antibodies.
In the second study Merck touted Wednesday, participants who received V114 showed an equivalent immune response to all 15 serotypes across three separate lots of the vaccine.
Merck only shared top-line results and plans to present further data at an upcoming scientific congress. The results follow two other phase 3 wins for the vaccine from June. In total, Merck is running 16 phase 3 studies on the vaccine.
With the latest results, Merck is ready to move ahead with an FDA filing before the end of the year, the company said Wednesday. Pfizer, meanwhile, is also moving ahead on that timeline with its 20-valent vaccine candidate after positive phase 3 data from March, setting up a duel for the next-gen pneumococcal vaccine market.
In that study, the Pfizer shot—a follow-up to Prevnar 13, which generated $5.8 billion last year—met immunogenicity goals for the serotypes covered by Prevnar 13 and six others, missing its target for serotype 8.
Ahead of the upcoming market clash, Cantor Fitzgerald analyst Louise Chen and her team have discussed potential scenarios with doctors. The doctors are watching to see which company will be first with its next-gen adult vaccine, as well as first with a pediatric shot. Further, docs are curious to see how approvals will change CDC vaccine recommendations, potential pricing for news shots and more.
Earlier this summer, SVB Leerink analyst Geoffrey Porges predicted Pfizer’s new vaccine would “ultimately win majority share” in adults. In the infant indication, there’s more uncertainty, he wrote; Merck has a head start in testing for that population.
Next-gen vaccines are needed, and not just because diseases caused by serotypes not included in licensed shots are increasing. Even the serotypes included in licensed vaccines have caused disease, further prompting the need for better vaccines.