Investigational PCV Meets Safety and Immunogenicity Objectives in Initial Phase 3 Studies

Merck has announced results from 2 initial Phase 3 studies, PNEU-FLU and PNEU-WAY, evaluating the firm’s 15-valent pneumococcal conjugate vaccine (PCV).

According to investigators, the vaccine candidate (V114) met safety and immunogenicity objectives. Data were published using the International Symposium on Pneumococci and Pneumococcal Diseases online digital library.

V114 uses pneumococcal polysaccharides from 15 serotypes conjugated to a CRM197 carrier protein, including serotypes 22F and 33F. These serotypes are widely associated with invasive pneumococcal disease globally and are not found in the currently licensed pneumococcal conjugate vaccine for adults.

“Certain populations are at greater risk for pneumococcal disease, reinforcing the importance of investigating new interventions focused on their specific needs,” said Luwy Musey, MD, executive director in biologics, vaccine clinical research, at Merck Research Laboratories. “Results from these first two Phase 3 studies of V114 are encouraging and we look forward to sharing additional data in the future from our ongoing clinical development program, including our pivotal studies assessing the immunogenicity of V114 and its potential to protect against the serotypes most likely to cause invasive disease.”

Altogether, 16 trials are involved in the Phase 3 clinic al development of V114. Trial organizers are seeking volunteers who are at increased risk for pneumococcal disease as well as people who are immunocompromised.

PNEU-WAY was a Phase 3, multicenter, randomized, double-blind, active comparator-controlled study. The study team sought to evaluate the tolerability, safety, and immunogenicity of V114 (followed by administration of PNEUMOVAX 23, 8 weeks later) in adults 18 years of age or older living with HIV.

A total of 302 participants were randomized in PNEU-WAY. A total of 152 were randomized 1:1 to receive V114 and 150 to the currently available 13-valent pneumococcal conjugate vaccine (PCV13) followed by PNEUMOVAX 23.

“V114 met its primary immunogenicity objective as measured by serotype-specific opsonophagocytic activity (OPA) Geometric Mean Titers (GMTs) and Immunoglobulin G (IgG) Geometric Mean Concentrations (GMCs) for all 15 serotypes contained in the vaccine at 30 days post-vaccination.” Merck reported.

Additionally, immune responses were more substantial in the V114 group compared with the PCV13 group for serotypes 22F and 33F. The safety profile of V114 was comparable with PCV13.

PNEU-FLU was a Phase 3, multicenter, randomized, double-blind, placebo-controlled study. V114 was administered concomitantly or non-concomitantly with the influenza vaccine in 1200 healthy adults 50 years of age or older.

PNEU-FLU met primary immunogenicity objectives and V114 administered concomitantly with QIV was noninferior compared to V114 administered non-concomitantly with influenza vaccine.