I don’t know where you are getting your information. Drug discovery is still trial and error. Hundreds of tubes containing infected tissue are placed in racks and some drug combination is injected into each one. These tubes are then examined to see if any of these drugs do anything. If there is a positive response, a few may go on to animal trials. If the animals don’t die or suffer serious side effects, human trials start. If that goes well, you may see TV commercials for new drugs that always end with serious risks for some percentage of users. My favorites are: liver failure, kidney failure, heart failure and death. Death is sometimes described as “a sudden fatal reaction.”
Gene editing has nothing to do with evolution. CRISPER/Cas 9 was designed by human beings. The original CRISPR was the hammer and chisel approach. It was damaging neighboring genes. The latest version is still encountering various problems related to what scientists don’t know. The other problem is speed. The original CRISPR was slow, the latest version is faster but it’s regarded as not fast enough. Scientists are working on some ways to increase speed but the journals are reporting the same trial and error approach.