Pfizer’s Phase II results strengthen likely regulatory approval for 20vPnC
On September 9, Pfizer announced positive results for a randomised, double-blind proof-of-concept Phase II study following administration of three doses in a four-dose series to assess the safety and immunogenicity of its 20-valent pneumococcal conjugate vaccine candidate (20vPnC).
GlobalData expects the positive trial data will strengthen the likelihood for a positive Phase III result and also for regulatory approval for 20vPnC.
The Phase II trial enrolled 460 healthy infants and the vaccine candidate showed an overall safety profile similar to Prevnar 13, which is the preferred pneumococcal vaccine for infants in most regions, including the US and five major European countries (5EU: France, Germany, Italy, Spain, the UK). 20vPnC is designed to protect against 20 Streptococcus pneumoniae serotypes, including the 13 serotypes found in Prevnar 13, but with the addition of seven serotypes thought to cause significant pneumococcal disease.
Although data for the fourth dose are not available yet, GlobalData expects that results will be similar to the three doses that the Phase III trials will also be positive, and 20vPnC will gain approval for infants. Pfizer has also announced the completion of enrollment for the three Phase III pivotal trials evaluating 20vPnC for the prevention of invasive pneumococcal disease and pneumonia in adults ages 18 years and older. The positive Phase II results reinforce Pfizer remaining on track for a Biologics License Application (BLA) submission for adults by the end of 2020.
Another pneumococcal candidate vaccine is Merck’s 15-valent conjugate pneumococcal vaccine (V-114) with two additional serotypes relative to Prevnar 13. Like 20vPnC, V-114 is also in Phase III, and key opinion leaders (KOLs) interviewed by GlobalData indicate that addition of seven more serotypes is far more desirable for a pneumococcal vaccine candidate and may result in changes in recommendations from Prevnar 13 to 20vPnC. However, when V-114 is launched, it will be less likely to replace Prevnar 13 as being the recommended vaccine due to the marginal improvements in serotype coverage, resulting in lower physician usage.
GlobalData (2019). Merck’s Threat to Pfizer’s Lucrative Prevnar Brand Gains Ground with Positive Phase II Results. May 2019, GDHC2439EI
GlobalData (2019). Merck’s Infant Pneumococcal Vaccine Snags FDA Breakthrough Designation, Threatening Pfizer’s Longstanding Market Dominance. February 2019, GDHC2256EI