A new study published in the Journal of the National Cancer Institute reveals that approximately 16% of patients participating in phase 2 cancer clinical trials receive treatments that eventually secure FDA approval, offering valuable insights for both drug development and patient recruitment strategies.
Study Scope and Methodology
Researchers analyzed 2,730 phase 2 clinical trials initiated between November 2012 and November 2015. From these, they examined 400 randomly sampled trials encompassing 25,002 patient-participants across 608 cohorts, investigating 332 distinct drugs. The study's comprehensive scope included various treatment approaches, with some drugs being tested in multiple trials - 25 drugs underwent more than 10 trials, 155 were tested in 2-10 trials, and 152 in single trials.
Key Findings and Clinical Implications
The analysis revealed that 71 drug regimens ultimately received FDA approval for their tested indications. This translates to approximately one in six patients in phase 2 trials receiving treatments that would later be approved. However, lead author Charlotte Ouimet emphasizes an important caveat: "Keep in mind that approved drugs don't work for every person. For many FDA approved cancer drugs, only half to a tenth of patients meaningfully benefit."
Context in Drug Development Pipeline
Phase 2 trials represent a critical middle ground in drug development, following initial safety studies but preceding large-scale efficacy trials. Unlike phase 1 trials, which focus on safety and dosing, phase 2 studies administer drugs at doses intended for routine use, making efficacy assessment a crucial consideration for potential participants.
Implications for Patient Decision-Making
For cancer patients considering clinical trial participation, these findings provide valuable context for informed decision-making. "If you're a cancer patient and you are invited into a phase 2 trial, keep in mind that five of six patients get treatments that do not go on to approval," notes study author Jonathan Kimmelman. He adds that while these odds are "dramatically better" than phase 1 trials, they remain lower than phase 3 trials, where approximately one in three patients receive eventually approved treatments.
Impact on Clinical Trial Recruitment
These statistics may actually encourage participation in phase 2 trials, particularly among patients with advanced cancers who have exhausted standard treatment options. A 16% probability of receiving a drug that later achieves FDA approval represents meaningful odds for many patients in this situation, especially when compared to earlier phase trials.
