so doctors who rarely use the term game changer call two forthcoming covid pills game changers. they say they dramatically reduce hospitalization or death for people with mild to moderate covid. but the success really all depends on testing, which we haven't been great at. cnn's elizabeth cohen here to explain. >> john, as amazing as the results are of these clinical trials by merck and pfizer, you know what is even better, not getting covid at all. vaccines are more important than even these trucks. let's take a look at the results that merck and pfizer not when they did that with these anti-virals drugs. for america, they had some people taking a placebo, a drug that does nothing. nine deaths from covid in the group that got the placebo,