Could you simplify or paraphrase "the informed consent of study subjects"?

Question

The Kefauver-Harris Amendments enacted in 1962 were groundbreaking in their attempts to ensure the safety and effectiveness of all new drugs on the U.S. market. The amendments gave the FDA specific authority to approve a manufacturer's marketing application before a drug could be available for commercial use. Firms now had to prove safety and provide substantial evidence of effectiveness for the drug's intended use. The required evidence had to consist of adequate and well-controlled studies. The amendments helped establish rules of clinical drug investigation and the informed consent of study subjects. The amendments also required that drug-related adverse events be reported to the FDA.

What kind of consent would be called an informed consent? Could you also paraphrase the sentence in simple English?

Answer 1

Consent:
Agree to do something - take the experimental medicine in this case.

Informed:
With knowledge - about possible side-effects or long-term damage.

-> Informed consent of study subjects:
Agreement of persons to participate in the study while fully knowing what is happening or could happen when doing so.

Answer 2

I think I see what you're getting at - it seems a little redundant. How can you get un-informed consent? In order to get consent, they'd have to be informed.

So a different way of saying it (maybe the paraphrase you're looking for) is "The amendments helped establish rules of clinical drug investigation and the consent of study subjects."