On Oct. 20, 2020, Merck announced findings from two additional Phase 3 studies evaluating the safety, tolerability and immunogenicity of V114, the company’s investigational 15-valent pneumococcal conjugate vaccine. In the PNEU-PATH (V114-016) study, healthy adults 50 years of age or older received V114 or PCV13 followed by PNEUMOVAX^® 23 one year later. Immune responses following vaccination with PNEUMOVAX 23 (month 13) were comparable in both vaccination groups for the 15 serotypes in V114.

Results also showed that at 30 days post vaccination with either V114 or PCV13 (day 30), immune responses were comparable for both groups across the 13 serotypes shared by the conjugate vaccines and higher in the V114 group for serotypes 22F and 33F, the two serotypes not included in PCV13. In PNEU-DAY (V114-017), a Phase 3 study in immunocompetent adults 18 to 49 years of age with underlying medical conditions associated with increased risk for pneumococcal disease, V114 generated immune responses generally comparable to PCV13 for the 13 shared serotypes and higher immune responses for serotypes 22F and 33F at 30 days post-vaccination.

Results from both studies are based on opsonophagocytic activity (OPA) responses – a measure of vaccine-induced functional antibodies. V114 was generally well tolerated in both studies, with a safety profile consistent with that observed for V114 in previously reported studies. Findings from the V114 Phase 3 clinical program in adults, including PNEU-PATH and PNEU-DAY, will be presented at a future scientific congress. Plans for global regulatory licensure applications, beginning with the U.S. Food and Drug Administration before the end of the year, remain on track.

There are more than 90 different types of pneumococcal bacteria which can affect adults differently than children. Pneumococcal serotypes not in the currently licensed conjugate vaccine, such as 22F and 33F, are among the most common serotypes causing invasive pneumococcal disease in parts of the world, including the U.S., among adults 65 years of age or older. Invasive pneumococcal disease due to serotypes 22F and 33F has been linked to higher case fatality rates and prolonged hospitalization in adults. Overall, adults with certain medical conditions, such as heart disease, diabetes or chronic obstructive pulmonary disease (COPD), have a higher risk for pneumococcal disease compared to those without these conditions.

The V114 Phase 3 clinical development program is comprised of 16 trials investigating the safety, tolerability and immunogenicity of V114 in a variety of populations who are at increased risk for pneumococcal disease, including healthy older adults and children, as well as people who are immunocompromised or have certain chronic medical conditions.

PNEU-PATH is a Phase 3, multi-center, randomized, double-blind, active comparator-controlled study evaluating the safety, tolerability and immunogenicity of V114 followed by administration of PNEUMOVAX 23 one year later in healthy adults 50 years of age or older (n=652). The primary endpoints included serotype specific OPA geometric mean titers (GMTs) at 30 days post-vaccination with PNEUMOVAX 23. The serotype specific OPA GMTs at 30 days post-vaccination with PNEUMOVAX 23 were comparable in the V114 and PCV13 groups for all 15 serotypes in V114.

Secondary endpoints included serotype specific OPA GMTs at 30 days post-vaccination with either V114 or PCV13. The OPA GMTs were comparable for the 13 shared serotypes between V114 and PCV13 at 30 days post-vaccination with either V114 or PCV13. The OPA GMTs were higher in the V114 group compared with the PCV13 group for the two serotypes unique to V114 (22F and 33F) at 30 days post-vaccination with either V114 or PCV13. Results of the safety analyses demonstrated that V114 was generally well tolerated and can be followed by PNEUMOVAX 23.