Pfizer has announced positive outcomes for its 20-valent pneumococcal conjugate vaccine candidate (20vPnC), from a Phase 3 study conducted in infants, in the US.

In the trial, the vaccine showed effectiveness in preventing invasive pneumococcal disease (IPD) caused by the 20 Streptococcus pneumoniae serotypes, in the paediatric population.

The study had two co-primary objectives, the first related to immunogenicity responses one month after the third and fourth doses of the four-dose vaccination series, respectively.

The second includes non-inferiority (NI) of the percentage of participants with serotype-specific immunoglobin G (IgG) concentrations after Dose 3 and NI of IgG geometric mean concentrations (GMCs) after Dose 4.

In the clinical trial, all the 20 serotypes had met the co-primary objective of NI of IgG GMCs after Dose 4, said Pfizer.

Fourteen of the 20 serotypes met the co-primary objective, and all serotypes met non-inferiority for the key secondary objective of IgG GMCs after Dose 3.

Also, all the 20 serotypes in the vaccine candidate showed superior functional responses (OPA) and showed increase in antibody responses after Dose 4.

The 20vPnC candidate showed an overall safety profile that was consistent with Prevnar 13.

Pfizer vaccine research and development senior vice president and chief scientific officer Annaliesa Anderson said: “We are encouraged by today’s data which show that if approved for a pediatric indication, 20vPnC would have the potential to cover more of the clinically significant remaining burden of infant pneumococcal disease than any other available pneumococcal conjugate vaccine.

“We are grateful to everyone who made this study possible, including the study investigators and in particular the trial participants and their parents/guardians for their contribution to this important research.”

The 20vPnC vaccine candidate includes 13 serotypes already included in Prevnar 13 including stereotype 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F, with seven new serotypes.

The 20 serotypes included in the vaccine are responsible for global causes of invasive pneumococcal disease (IPD), along with antibiotic resistance, and meningitis.

In August 2020, the 20vPnC received the Breakthrough Therapy Designation from the US Food and Drug Administration (FDA) for use in infants, children, and adolescents.

In June last year, the FDA approved PREVNAR 20 for the prevention of invasive disease and pneumonia caused by the 20 Streptococcus pneumoniae serotypes in adults.

Furthermore, Pfizer intends to submit a supplemental Biologics License Application (sBLA) with the FDA by the end of this year, based on the positive safety and immunogenicity data.