The Food and Drug Administration (FDA) has approved Merck’s new vaccine, Capvaxive, designed to protect adults from pneumococcus bacteria, which can cause severe illnesses and pneumonia, the company announced on Monday.
Capvaxive is formulated to protect against 21 strains of pneumococcus, offering broader protection against severe pneumococcal disease than existing vaccines. This disease can lead to serious infections like pneumonia, meningitis (inflammation around the brain and spinal cord), and bacteremia (bloodstream infection). Notably, Capvaxive is the first pneumococcal conjugate vaccine specifically designed for adults.
While pneumococcal disease can affect healthy adults, it poses a higher risk to older individuals and those with chronic or immunocompromising conditions. Heather Platt, Merck’s product development team lead, emphasized the significant impact of this disease on adults, noting that chronic lung disease, including asthma, increases the risk of severe illness and hospitalization.
“Chronic lung disease patients, even those with asthma, face higher risks of pneumococcal disease, leading to hospitalizations and affecting their quality of life,” Platt told CNBC. She highlighted that around 150,000 U.S. adults are hospitalized annually with pneumococcal pneumonia, and the highest mortality rates from invasive pneumococcal disease are among adults aged 50 and above.
Despite FDA approval, Capvaxive will not be immediately available. The Centers for Disease Control and Prevention (CDC) advisory panel is set to meet on June 27 to determine eligibility for the vaccine. Merck plans to support the committee’s decision and aims to supply the vaccine by late summer.
Merck’s Competitive Edge
Capvaxive is expected to be a significant growth driver for Merck as it prepares for the eventual loss of exclusivity for its cancer drug Keytruda in 2028. Analysts from Cantor Fitzgerald project that the pneumococcal conjugate vaccine market, currently valued at around $7 billion, could grow to over $10 billion in the coming years.
The new vaccine bolsters Merck’s position in a competitive market that includes Pfizer, the current leader with its Prevnar 20 vaccine. While Merck already offers two pneumococcal vaccines, they are not specifically designed for adults. For instance, Vaxneuvance is approved for patients as young as six weeks.
Pfizer’s Prevnar 20 currently dominates the adult market, but Merck’s Capvaxive is expected to capture a significant share. Platt expressed confidence in the rapid adoption of Capvaxive, citing data that she believes will resonate with clinicians and policymakers.
Capvaxive offers protection against eight additional strains of pneumococcus not covered by any other approved vaccines. These eight strains account for approximately 30% of invasive pneumococcal disease cases in patients aged 65 and above. Overall, the 21 strains in Capvaxive cover about 85% of invasive pneumococcal disease cases in this age group, compared to the 51% coverage provided by Pfizer’s Prevnar 20.
The FDA’s approval of Capvaxive is based in part on Merck’s STRIDE-3 late-stage trial, which compared the new vaccine to Pfizer’s Prevnar 20 in adults aged 18 and up who had not previously received a pneumococcal vaccine.
