Pfzier announced topline results from a second phase 3 trial investigating its 20-valent pneumococcal polysaccharide conjugate vaccine (20vPnC) for the prevention of invasive disease and pneumonia caused by Streptococcus pneumoniae serotypes in adults aged 18 to 49 years.

The randomized, double-blind trial evaluated the efficacy and safety of 3 lots of 20vPnC in 1700 adult patients with no history of pneumococcal vaccination. Patients were randomized 2:2:2:1 to receive a single dose of 20vPnC (3 different lots) or 13-valent pneumococcal conjugate vaccine (Prevnar 13). 

Results showed that all 3 lots of 20vPnC elicited equivalent immune responses for all 20 serotypes, achieving the immunogenicity objective of the study. Additionally, the safety profile of 20vPnC was similar to Prevnar 13.

“We are excited by the progress of our adult development program for 20vPnC as this is the second phase 3 trial for this investigational vaccine for which we have positive topline data,” said Kathrin U. Jansen, PhD, SVP and Head of Vaccine Research & Development, Pfizer. “Demonstration of lot consistency is critical to help ensure that vaccine recipients receive the same level of protection irrespective of the manufactured lot used.”

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The Company has completed 3 clinical trials, enrolling over 6000 adults, as part of it’s phase 3 development program for 20vPnC. The Food and Drug Administration (FDA) previously granted Breakthrough Therapy and Fast Track designations to 20vPnC for this indication. 

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