Merck ends development of two potential COVID-19 vaccines

Merck is giving up on two potential COVID-19 vaccines following poor results in early-stage studies. The drugmaker said Monday that it will focus instead on studying two possible treatments for the virus that also have yet to be approved by regulators. The company said its potential vaccines were well tolerated by patients, but they generated an inferior immune system response compared with other vaccines. Merck entered the race to fight COVID-19 later than other top drugmakers.