The response to that should be twofold: Does that mean no drug is really safe or efficacious given the limits of clinical trials. Second, , why not do head to head studies of treatment approaches developed by "purists" and those "corrupted" by industry and see who does better? We actually have some examples.. ALLHAT and CATIE were run by purists, the UK's NICE system of comparative effectiveness is too.
For the most part, purists are lazy. They simply do meta-analyses of selective group of clinical trials that have exclusion critiera that will produce outcomes they support.
Meanwhile, are the purists, who take money from trial lawyers, left wing foundations funded by George Soros, agenda driven organizations and have their own biases really pure?