New COVID-19 Vaccine Trials Will Need an Active Comparator

Approved vaccines and the diminishing numbers of unexposed individuals are making placebo-controlled trials for COVID-19 vaccines a thing of the past, so researchers will have to rely on active comparators to develop second-generation shots.

The problem is getting ahold of those doses, said Melanie Saville, director of vaccine research and development at the Coalition for Epidemic Preparedness Innovations (CEPI).

“Unfortunately, lack of access to comparator vaccines is already stalling the development of promising vaccine candidates, and the potential impact on COVID-19 vaccine development and supply is huge,” Saville said in a letter published in the Sept. 7 issue of Nature.

Seven vaccines are currently approved by the World Health Organization, but all the stock is bound by contractual agreement that restricts its use to public health measures, eliminating the possibility of clinical research, Saville said