Merck's next-gen pneumococcal vaccine puts the heat on Pfizer with phase 3 wins

Merck and Pfizer are racing their next-gen pneumococcal vaccines to the finish line in a multibillion-dollar field. But while Merck this week posted two trial wins, they won't be enough to secure it a lead in the market-share battle to come, one analyst predicts.

Merck's 15-valent vaccine candidate met its objectives in two phase 3 studies in certain patient populations, the New Jersey drugmaker said Monday. One study tested the vaccine candidate in patients 18 and older who are living with HIV, and the other focused on patients 50 and older who also received a quadrivalent flu vaccine.  

RELATED: Merck pits its pneumococcal shot against Pfizer's mammoth Prevnar in head-to-head phase 3 

In the first study, V114 elicited an immune response against all 15 serotypes included in the shot. The second study showed that the vaccine can be given at the same time as a quadrivalent flu vaccine, Merck said. The tests are only two out of 16 late-stage studies for the vaccine in various patient populations. But with the data, the drugmaker is preparing to file its next-gen pneumococcal vaccine candidate, V114, with regulators worldwide. 

On the company’s first-quarter conference call earlier this year, R&D head Roger Perlmutter said Merck was “really very enthusiastic about this vaccine because of the important new serotypes in it and also the balance with respect to the immune response that we saw in our V114 studies” in earlier testing. 

But looking ahead toward the market faceoff, SVB Leerink analyst Geoffrey Porges predicted in a note to clients that it would be Pfizer's vaccine that would "ultimately win majority share" in adults. Pfizer is pushing forward with a 20-valent shot, a follow-up to the mega-successful Prevnar 13 that pulled in $5.8 billion last year. The company unveiled positive phase 3 data in March and said it was on track for an FDA filing this year. 

RELATED: Pfizer touts latest next-gen pneumococcal data in infants amid race to market with Merck 

Merck may have the upper hand in the infant indication, though, which "faces more uncertainty," Porges noted. Merck has already started a phase 3 trial in infants that's set to wrap up next May, but Pfizer's trial enrollment could hit snags due to the pandemic, he said, possibly giving Merck a head start in that arena.