FDA Approves Merck’s Capvaxive to Prevent Invasive Pneumococcal Disease, Pneumococcal Pneumonia in Adults Over 18 Years of Age

Image Credit: Adobe Stock Images/Dr_Microbe

The FDA has approved Merck’s Capvaxive 21-valent pneumococcal conjugate vaccine to prevent invasive pneumococcal disease (IPD) and pneumococcal pneumonia in adults 18 years of age and older. According to the company, Capvaxive provides a superior level of protection compared to other vaccines, such as PCV20, through targeting eight specific serotypes that lead to a high number of IPD cases in adults. The approval was based on positive results from the Phase III STRIDE-3, STRIDE-5, and STRIDE-6 trials, which compared Capvaxive to PCV20, and in a combination of patients who were vaccine-naïve and vaccine-experienced.¹

“Complications from invasive pneumococcal disease can lead to hospitalization, organ damage and even death. Many cases of adult disease are caused by serotypes not included in other approved pneumococcal conjugate vaccines,” said Walter Orenstein, MD, professor emeritus of medicine, epidemiology, global health and pediatrics, Emory University, Merck scientific advisory committee member, in a press release. “Capvaxive is designed to include the serotypes that cause the majority of invasive pneumococcal disease in adults, helping to protect adults against invasive pneumococcal disease and pneumococcal pneumonia.”

The double-blind STRIDE-3 trial compared Capvaxive to PCV20 in adult patients who had not previously received a pneumococcal conjugate vaccine. Patients were divided into two cohorts, with those over 50 years of age placed into the first cohort and patients aged 49 years and younger placed in the second cohort. All patients were randomly assigned to receive either Capvaxive or PCV20. In the 50 years and older cohort, Capvaxive was found to be equal to PCV20 in all 10 of the serotype polysaccharides that they shared. Additionally, it was found to be superior to PCV20 for 10 of 11 serotype polysaccharides included in Capvaxive. The immune response for serotype 15C showed promise but requires further investigation, and it had a comparable safety profile to PCV20, according to the investigators. In the younger cohort, the treatment demonstrated non-inferior immune responses compared to the older cohort.

The randomized, double-blind STRIDE-5 trial evaluated Capvaxive when administered concomitantly or sequentially with quadrivalent influenza vaccine (QIV) in adults over the age of 50 years. The results indicated that Capvaxive can be safely given at the same time or one month apart from QIV because immune responses from both vaccines stay strong in both administration methods. Further, adverse events (AEs) were similar whether QIV was taken with Capvaxive or Capvaxive was taken alone.

The randomized descriptive STRIDE-6 trial evaluated adults over the age of 50 years who had previously received a pneumococcal vaccine at a minimum of one year prior to the start of the trial. In this study, patients were divided into three cohorts, with cohort one consisting of those who have been vaccinated with PPSV23, cohort two included patients who had previously taken PCV13, and cohort three included those administered PPSV23 followed by or preceded by PCV13, PPSV23 preceded by PCV15, or PCV15 alone. Cohort one was randomly assignedf to receive either Capvaxive or PCV15, cohort two was given either Capvaxive or PPSV23, and all of cohort three received Capvaxive. Results from this study found:

• In patients previously vaccinated with either PPSV23 or PCV13, Capvaxive was found to be a strong booster.
• For cohort one, Capvaxive was comparable to PCV15 for the six common serotypes, and higher for the 15 unique serotypes and serotype 15B.
• For cohort two, Capvaxive was comparable to PPSV23 for the 12 common serotypes and serotype 15B, with a higher number associated with the nine unique serotypes.
• Capvaxive was found to have a safety profile consistent with PCV15 and PPSV23.¹

“Today’s approval is a testament to our population-specific strategy behind Capvaxive, which demonstrated robust immunogenicity in a range of adult populations and is driven by a deep understanding of pneumococcal disease,” said Dean Y. Li, MD, PhD, president, Merck Research Laboratories, in the press release. “We are proud to provide Capvaxive as a new option specifically designed to help protect against the majority of invasive pneumococcal disease-causing serotypes in adults.”

Reference

1. U.S. FDA Approves CAPVAXIVE™ (Pneumococcal 21-valent Conjugate Vaccine) for Prevention of Invasive Pneumococcal Disease and Pneumococcal Pneumonia in Adults. Merck. June 17, 2024. Accessed June 18, 2024. https://www.merck.com/news/u-s-fda-approves-capvaxive-pneumococcal-21-valent-conjugate-vaccine-for-prevention-of-invasive-pneumococcal-disease-and-pneumococcal-pneumonia-in-adults/