FDA approves Merck pneumococcal disease vaccine designed for adults

The Food and Drug Administration on Monday approved Merck‘s latest vaccine designed to guard adults from a bacteria known as pneumococcus that may cause serious illnesses and a lung infection called pneumonia, the drugmaker said.

Merck’s shot, called Capvaxive, specifically protects against 21 strains of that bacteria to forestall a severe type of pneumococcal disease that may spread to other parts of the body and result in pneumonia. It’s the primary pneumococcal conjugate vaccine designed specifically for adults and goals to offer broader protection than the available shots in the marketplace, based on the drugmaker.

Healthy adults can suffer from pneumococcal disease. But older patients and people with chronic or immunocompromising health conditions are at increased risk for the illness, especially the more serious or so-called “invasive” form. 

Invasive pneumococcal disease can result in meningitis, an infection that causes inflammation in the world surrounding the brain and spinal cord, and an infection within the bloodstream called bacteremia. 

“If you might have chronic lung disease, even asthma, you might have a better risk of getting sick with pneumococcal disease, after which being within the hospital, losing out on work,” Heather Platt, Merck’s product development team lead for the newly cleared vaccine, told CNBC in an interview. “Those are things which have an actual impact on adults and kids, their quality of life.”

Around 150,000 U.S. adults are hospitalized with invasive pneumococcal disease annually, Platt said. Death from the more serious type of the disease is highest amongst adults 50 and above, Merck said in a release in December.

Even after the FDA approval, the corporate’s single-dose vaccine won’t reach patients just yet. An advisory panel to the Centers for Disease Control and Prevention will meet on June 27 to debate who must be eligible for the shot.

Platt said Merck will support the committee’s decision and is prepared to produce the vaccine by late summer. 

Some analysts view Capvaxive as a key growth driver for Merck because it prepares to offset losses from its blockbuster cancer drug Keytruda, which can lose exclusivity within the U.S. in 2028. 

Merck’s newly approved shot could boost its competitive edge in that space, which incorporates drugmaker Pfizer. Merck currently markets two pneumococcal shots, but neither is specifically designed for adults. For instance, the corporate’s existing shot Vaxneuvance is approved within the U.S. for patients 6 weeks of age and older.

Pfizer’s single-dose pneumococcal vaccine, Prevnar 20, is the present beneficial product for adults. But Merck expects its latest shot to capture the vast majority of market share amongst adults, Platt said. 

“We do expect there to be rapid uptake of” Capvaxive, she said, adding that the corporate is confident that data on the shot will “really resonate” with clinicians and policymakers. 

Merck’s pneumococcal vaccine protects against eight strains of the bacteria that will not be included in every other approved shot for the disease. Those eight strains account for roughly 30% of invasive pneumococcal disease cases in patients 65, based on a release from Merck, citing CDC data from 2018 to 2021. 

The 21 strains included in Merck’s shot account for roughly 85% of invasive pneumococcal disease cases in adults 65 and above, Merck, citing the CDC data. Meanwhile, Pfizer’s Prevnar targets strains that only account for roughly 52% of cases, based on the identical CDC data. 

The FDA’s approval is partly based on Merck’s late-stage trial called STRIDE-3 that pitted the vaccine against Pfizer’s Prevnar 20 in adults 18 and up who had not previously received a pneumococcal vaccine.