Pfizer announces positive results from phase 3 study of 20-valent pneumococcal conjugate vaccine

New York: Pfizer Inc. has announced top-line results from one of its Phase 3 studies, which evaluated the safety and immunogenicity of its 20-valent pneumococcal conjugate vaccine (20vPnC) candidate in adults 18 years of age or older not previously vaccinated against pneumococcal disease.

The primary immunogenicity objectives of non-inferiority for the 20 serotypes included in 20vPnC in adults 60 years of age and older at one month after vaccination were met for all serotypes in common with licensed Prevnar 13® (pneumococcal 13-valent Conjugate Vaccine [Diphtheria CRM197 Protein]) and six of the seven additional serotypes when compared to a licensed pneumococcal polysaccharide vaccine (PPSV23); one of the new seven serotypes missed noninferiority criteria by a small margin.

Secondary immunogenicity objectives for adults 18-59 years old compared to those 60-64 years old met non-inferiority for all 20 serotypes. The safety objectives were met in adults 18 years of age or older demonstrating that the safety and tolerability of 20vPnC were comparable to licensed pneumococcal vaccines. Based on prior discussions with regulators, these data are expected to meet licensure criteria.

"We are encouraged by the results from this study and remain on track to file the adult 20vPnC indication with the FDA by the end of 2020. 20vPnC builds on a well-established and trusted foundation of pneumococcal conjugate experience and science that Pfizer has accumulated for more than 20 years," said Kathrin U. Jansen, Ph.D., Senior Vice President and Head of Vaccine Research & Development, Pfizer. "The results from this pivotal study provide evidence that the 20vPnC vaccine is expected to have a comparable safety profile and likely be as effective as Prevnar 13 in helping prevent invasive pneumococcal disease and pneumonia due to the 13 serotypes in Prevnar 13, and also effective against disease due to the seven additional pneumococcal serotypes in adults 18 years of age or older."

Pfizer's 20vPnC vaccine candidate includes 13 serotypes already included in Prevnar 13. The seven new serotypes included in 20vPnC are global causes of invasive pneumococcal disease (IPD), and are associated with high case-fatality rates, antibiotic resistance and/or meningitis. Globally, pneumococcal pneumonia is estimated to cause about 500,000 deaths and 30 million episodes in adults 70 years and older annually.15 Together, the 20 serotypes included in 20vPnC are responsible for the majority of currently circulating pneumococcal disease in the U.S. and globally.

"The 20-valent pneumococcal conjugate vaccine was developed to overcome the limitations attributed to pneumococcal plain polysaccharide vaccines. 20vPnC, like its predecessor Prevnar 13, is expected to provide immunological memory against the 20 serotypes included in the vaccine and to afford protection against non-bacteremic pneumonia for those 20 serotypes," said Luis Jodar, Ph.D., Chief Medical and Scientific Affairs Officer, Pfizer Vaccines. "This is particularly important for the seven additional pneumococcal serotypes due to the burden of pneumonia caused by the new serotypes and the lack of herd protection for adults since the current pediatric vaccine does not protect against the seven additional strains."

Pfizer will seek to present and publish outcomes from this clinical trial at a future date once safety and immunogenicity data have been fully analyzed.

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