- An experimental pneumococcal vaccine developed by Merck & Co. proved comparable to Pfizer's market-leading shot Prevnar 13 in two late-stage studies, Merck said Tuesday, adding further evidence to the case for approval that the company plans to make to the Food and Drug Administration later this year.
- In one trial, Merck's candidate, known as V114, led to equivalent immune responses as Prevnar 13 in adults over 50. Importantly, vaccination with V114 also led to immune responses that were targeted against two pneumococcal serotypes that Prevnar 13 doesn't cover. Results from the other, in adults with underlying medical conditions that put them at risk for pneumococcal disease, were similar.
- V114 is an important vaccine for Merck, which hopes to challenge Pfizer in the lucrative pneumococcal vaccine market. Pfizer, which earned about $2.6 billion from Prevnar 13 sales between January and June this year, is also developing a second-generation pneumococcal vaccine.
With the announcement Tuesday, Merck has shared summary results for six of its 16 late-stage studies testing V114 in the prevention of pneumococcal disease.
The six trials that have succeeded to date include two crucial tests that Merck needs to support an application for U.S. approval, which the company intends to submit by the end of this year. Some 18,000 participants have been enrolled in V114 studies, with another 6,000 set to be recruited in trials that are new or ongoing.
Pneumococcal vaccines already on the market, like Prevnar 13 and Merck's decades-old Pneumovax 23, can prevent disease caused by up to 23 different strains, or serotypes, of pneumococcal bacteria. Recently, however, other strains not covered by current vaccines have been driving new pneumonia cases, fueling Merck and Pfizer's search for successor shots.
In the case of V114, the serotypes targeted are 22F and 33F, both of which aren't inoculated against by Prevnar 13. V114 differs from Pneumovax 23, meanwhile, in its construction: the latter is what's known as a polysaccharide vaccine, while V114 is a so-called conjugate vaccine like Prevnar 13.
After 30 days, participants in both of the studies announced Tuesday experienced immune responses against the 22F and 33F serotypes, Merck said.
Detailed data was not disclosed and will be presented at an upcoming medical meeting, according to the company.
Pfizer's next-generation penumococcal vaccine is also in late-stage development. Results announced by the pharma earlier this year showed inoculation led to immune responses comparable to Prevnar 13 on all strains included in the older shot, as well as equivalent responses to six of seven serotypes covered by Pneumovax 23.
Analysts view both Pfizer's candidate and V114 as crucial for the respective companies' vaccines businesses in the coming years. This year, however, development of each has taken a back seat to the companies' work in developing experimental coronavirus shots.
Pfizer, together with partner BioNTech, could soon report the first results from a large, late-stage efficacy study of its vaccine candidate, while Merck recently began human testing for one of two shots it plans to develop against the respiratory virus.