Merck & Co.’s next-generation pneumococcal vaccine has secured success in a pair of phase 3 trials, bringing the Big Pharma within touching distance of getting the first pneumococcal conjugate shot specifically designed for adults to market.
V116 targets serotypes that account for 85% of cases of invasive pneumococcal disease among individuals aged 65 and over in the U.S., including eight serotypes not currently covered by any licensed vaccines.
Merck reported this morning that the vaccine hit the primary and secondary endpoints across two phase 3 trials dubbed STRIDE-3 and STRIDE-6. In the STRIDE-3 study of 2,600 vaccine-naïve adults, a single dose of V116 demonstrated “statistically significant immune responses” after 30 days when compared to Pfizer’s FDA-approved Prevnar 20 shot.
The STRIDE-6 study recruited over 700 patients aged 50 years and older who had last received a pneumococcal vaccine at least a year earlier. For the trial, these patients either received V116, Merck’s Vaxneuvance or Prevnar 20. The results demonstrated that V116 was immunogenic for all 21 pneumococcal serotypes included in the vaccine, Merck said.
“In both studies, V116 had a safety profile comparable to the comparator in the studies,” the Big Pharma noted.
“Despite the availability of current pneumococcal conjugate vaccines, many adults remain vulnerable to pneumococcal disease, especially those who are older,” Eliav Barr, M.D., chief medical officer at Merck Research Laboratories, said in the release. “These results support the potential for V116 to become an important new preventative option for adults, regardless of prior pneumococcal vaccination status, by expanding coverage to include eight serotypes not currently included in any licensed vaccine.”
V116 is also in a number of ongoing phase 3 trials, including STRIDE-7 in adults with HIV, and STRIDE-4 in 18-49-year-olds.
Merck is keen to take on Pfizer's dominant and growing role in the pneumococcal market. Pfizer reported a 20% increase in revenue for the Prevnar family—which includes Prevnar 13 and Prevnar 20—in 2022 compared to the previous year. In total, the range raked in more than $6.3 billion in revenue.
The two U.S. Big Pharmas have already been in a race for the key infant population, with Merck winning an FDA nod in June 2022 for Vaxneuvance to vaccinate children from 6 weeks old through to 17 years. Pfizer received priority review of Prevnar for the same age group in January.