Merck & Co. said Monday that it is halting development of its two experimental Covid-19 vaccines, after early clinical trial data showed the shots triggered disappointing immune responses to the virus.
Early studies of the vaccines indicated that they produced inferior immune responses in subjects who received the injections compared to people who survived Covid-19 or took approved Covid-19 vaccines, the company said.
The exit removes a major vaccine player from the constellation of companies looking for shots to stem the spread of the virus, as the few companies that have been able to market shots struggle to meet high demand.
Kenilworth, NJ-based Merck, one of the world’s leading vaccine makers, said it would now focus on promoting two experimental Covid-19 drugs.
Merck said it expects test results for the pair of drugs in the coming weeks, and the company could ask regulators to allow their use if the results are positive.