Test article Tuesday

Pfizer has started testing a booster shot of its COVID-19 vaccine in combination with a pneumococcal vaccine candidate, the company announced this week. 

The company has enrolled 600 fully-vaccinated adults age 65 or older for the trial, which aims to analyze the safety of when both vaccines are co-administered and the immune responses produced by each shot.

The participants will have received their second dose of the Pfizer-BioNTech vaccine at least six months prior to entering the combination study. 

Individuals in the study will receive either the company’s 20-valent pneumococcal conjugate vaccine candidate (20vPnC) plus a third dose of the Pfizer-BioNTech COVID-19 vaccine — referred to as a "booster" — or they’ll get the 20vPnC shot plus a dummy booster. 

Some will also get the Pfizer booster shot plus a 20vPnC placebo, the company said.

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