Which act established the requirement for scientific proof of efficacy for new drug approval?

The requirement for scientific proof of efficacy for new drug approval was established by the Harris-Kefauver Amendments, which were enacted in 1962. These amendments expanded the authority of the FDA regarding drug approval processes and significant changes were made to bolster consumer protection. Prior to this legislation, the focus was primarily on the safety of drugs, stemming from earlier acts like the 1906 Pure Food and Drug Act and the 1938 Federal Food, Drug, and Cosmetic Act.

The Harris-Kefauver Amendments necessitated that drug manufacturers must not only demonstrate the safety of their drugs but also provide proof of their efficacy through substantial clinical evidence prior to obtaining approval for marketing. This was a pivotal moment in pharmaceutical regulation, as it laid the groundwork for ensuring that drugs available to the public were not only safe but also effective for their intended uses.

In contrast, the earlier acts such as the 1911 Shirley Amendments and the 1938 Federal Food, Drug, and Cosmetic Act did not mandate evidence of efficacy and only set forth requirements for safety and accurate labeling. This distinguishes the Harris-Kefauver Amendments as a significant evolution in the regulatory requirements surrounding drug approval.