REUTERS

Pfizer Inc (PFE.N)said on Monday it began testing fully vaccinated adults over 65 in a new study that uses the company's 20-valent pneumococcal conjugate vaccine (20vPnC) candidate with a third dose of the Pfizer-BioNTech COVID-19 shot.

The aim of the study is to understand if the combination of the vaccines is safe, and the immune response after adding the pneumonia vaccine to the existing COVID-19 vaccine, Pfizer said.

The vaccine candidate, 20vPnC, is being developed to help protect adults against 20 serotypes responsible for the majority of invasive pneumococcal disease and pneumonia.

The new study will include 600 adults who will be recruited from the two companies' late-stage COVID-19 vaccine study, after having received their second dose of the vaccine at least six months before entering the co-administration study.

COVID-19 vaccines were previously recommended to be administered alone. But based on experience with non-COVID vaccines, the U.S. Centers for Disease Control and Prevention has said COVID-19 shots and other vaccines can be given simultaneously or on the same day.

In December, the U.S. Food and Drug Administration (FDA)accepted for a priority review Pfizer's biologics license application for the investigational 20vPnC in adults over 18 and set an action date for a decision in June. The European Medicines Agency (EMA) accepted the company's marketing authorization application for 20vPnC two months later.