A forthcoming article for the special issue of the Journal of Law, Medicine and Ethics (JLME), edited by Marc Rodwin and supported by the Edmond J. Safra Center for Ethics, presents evidence that about 90 percent of all new drugs approved by the FDA over the past 30 years are little or no more effective for patients than existing drugs.
All of them may be better than indirect measures or placebos, but most are no better for patients than previous drugs approved as better against these measures. The few superior drugs make important contributions to the growing medicine chest of effective drugs.
https://ethics.harvard.edu/blog/risky-drugs-why-fda-cannot-be-trusted