Merck’s Pneumococcal Vaccine Elicits Immune Responses to 21 Serotypes in Children with one or More Health Conditions

Positive results from Merck’s Phase III STRIDE-13 trial for its Capvaxive vaccine, a pneumococcal 21-valent conjugate vaccine show it has the potential to provide additional protection in individuals 2 through 17 years old.

The study examined the safety, tolerability and immunogenicity of Capvaxive compared to PPSV23 in 882 children and adolescents aged 2 to 17 years of age who have completed a primary pediatric pneumococcal vaccination regimen and have one or more chronic medical conditions that put them at an increased risk of pneumococcal disease. Conditions included diabetes, chronic compensated liver disease, chronic lung disease, chronic heart disease or chronic kidney disease. In the study, participants were randomized 3:2 to receive a single dose of Capvaxive or PPSV23. Results showed the vaccine covered approximately 78 percent of invasive pneumococcal disease (IPD) cases, with 11 unique serotypes that account for approximately 34 percent of IPD cases. According to the company, the vaccine was found to be superior to the PPSV23 vaccine for each of the nine serotypes unique to Capvaxive, as measured by serotype-specific OPA GMTs at 30 days post-vaccination, which was the primary immunogenicity endpoint.

Although the vaccine was designed for adults and is currently approved for individuals 18 years of age and older, the pediatric population can benefit from this vaccine. “While Capvaxive was designed to specifically cover the serotypes that cause the majority of invasive pneumococcal disease (IPD) cases in adults, findings from STRIDE-13 underscore its added potential to help protect children and adolescents who are at an increased risk,” said Paula Annunziato, MD, senior vice president of infectious diseases and vaccines in Global Clinical Development at Merck Research Laboratories.