This study examined clinical trial success rates for new drug developments in gastric cancer since 1998. We also examined the clinical trial design features that may mitigate the risk of clinical trial failure.

Clinical trial data was obtained from clinicaltrials.gov. Drugs were included if they entered testing between January 1, 1998 and January 1, 2022 and were excluded if they did not have a completed phase I trial or treated secondary effects of gastric cancer. Transition probabilities were calculated for each phase and compared with industry averages. Success rates were determined based on biomarker usage, drug target, type of therapy, and drug chemistry.

Upon screening 1990 trials, 219 drugs met our inclusion criteria. The probability of a drug completing all phases of testing and obtaining FDA approval was 7%, which is below the 11% industry average. The use of biomarkers in clinical development resulted in nearly a 2-fold increase in the cumulative success rate. Biologics also exhibited higher success rates (17%) as opposed to small molecules (1%). This was true even when we compared both drug types that shared the same target. When comparing only receptor-targeted therapies, biologics (62%) continued to outperform small molecules (18%). Similarly, when narrowed down to drugs targeting solely HER2 receptors, biologics continued to prevail (64% vs. 24%).

Implementing biomarkers, receptor-targeted therapies, and biologics in clinical development improves clinical trial success rates in gastric cancer. Thus, physicians should prioritize the enrollment of gastric cancer patients in clinical trials that incorporate the aforementioned features.