Trends in the Quality of Evidence Supporting FDA Drug Approvals: Results from a Literature Review.

Context: New drug approvals in the United States must be supported by substantial evidence from "adequate and well-controlled" trials. The Food and Drug Administration (FDA) has flexibility in how it applies this standard.

Methods: The authors conducted a systematic literature review of studies evaluating the design and outcomes of the key trials supporting new drug approvals in the United States.

Analysis of Supportive Evidence for US Food and Drug Administration Approvals of Novel Drugs in 2020.

Importance: In recent years, drug approvals have been based on fewer, smaller, and less rigorous pivotal trials. Less robust preapproval testing raises questions about the efficacy and clinical value of these drugs.

Objective: To assess the regulatory context, pivotal design characteristics, and postmarket requirements (PMRs) and postmarket commitments (PMCs) of novel 2020 drug approvals to characterize the state of evidence at the time of approval.

New Drug Postmarketing Requirements and Commitments in the US: A Systematic Review of the Evidence.

Introduction: After the approval of a new drug, the Food and Drug Administration (FDA) may issue postmarketing requirements (PMRs), studies that the law requires manufacturers to conduct for drugs approved under certain conditions, and postmarketing commitments (PMCs), studies that the FDA and manufacturers agree should be conducted as a condition of approval.

Objective: With regulators' increasing reliance on gathering important evidence after initial product approval, we sought to assess the track record of PMRs and PMCs by synthesizing information about postmarketing study completion rates, timeliness, study types, and results reporting.

Methods: A systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted.