ZAI LAB (09688) shares plummeted 7.03% during Thursday's trading session following disappointing news regarding a key drug in its pipeline. The sharp decline comes after Amgen, ZAI LAB's partner, released the final analysis results of the FORTITUDE-101 Phase III clinical trial evaluating bemarituzumab for first-line gastric cancer treatment.

The trial, which combined bemarituzumab with chemotherapy (mFOLFOX6), initially showed promise with statistically significant and clinically meaningful improvement in overall survival compared to chemotherapy alone during the pre-specified interim analysis. However, the final analysis revealed that the magnitude of this survival benefit had diminished, casting doubt on the drug's efficacy and potential market success.

In light of these results, ZAI LAB announced it would delay submitting registration applications for bemarituzumab. Instead, the company will await the outcomes of the FORTITUDE-102 study, which is evaluating bemarituzumab in combination with nivolumab and chemotherapy in the same patient population. This strategic decision has likely contributed to investor concerns, as it potentially pushes back the timeline for bringing this treatment to market. The data from FORTITUDE-102 is not expected until late 2025 or the first half of 2026, signaling a significant wait for potential positive news that could revive investor confidence in this particular drug candidate.