The US Food and Drug Administration has announced plans to eliminate its long-standing expectation that new medicines be supported by at least two pivotal clinical trials, signaling a significant shift in regulatory policy aimed at accelerating patient access to innovative therapies.

Under the revised approach, a single well-designed, robust clinical study — supported by confirmatory or supplementary evidence — may be sufficient for approval in many cases. The move reflects evolving scientific standards, improved trial methodologies, and advances in statistical analysis that enhance the reliability of modern clinical data.

Historically, the two-study benchmark emerged from regulatory interpretations dating back to the 1960s, when lawmakers required “adequate and well-controlled investigations” to demonstrate safety and efficacy. Over time, this standard was commonly interpreted as requiring at least two independent trials. However, in recent years, the agency has already exercised flexibility in certain areas, particularly for treatments addressing serious or life-threatening conditions.

FDA leadership stated that the updated policy is intended to streamline development timelines, reduce duplication in clinical research, and encourage innovation while maintaining rigorous safety and efficacy standards. Officials believe the change could lower development costs and reduce time to market, potentially stimulating increased investment in drug development.

Regulatory experts note that the shift formalizes practices that have gradually evolved within the agency, especially in oncology and rare disease indications where single pivotal studies have often supported approvals when backed by strong evidence. The FDA is expected to provide further guidance clarifying how the new framework will be applied across therapeutic categories.