Novocure Ltd. shares declined roughly 10% after the company disclosed that its Phase 3 TRIDENT trial failed to achieve the study's primary endpoint of a statistically significant increase in overall survival for patients with newly diagnosed glioblastoma.
The randomized study compared two timing strategies for Tumor Treating Fields therapy - initiating treatment at the start of chemoradiation (Early Start Arm) versus beginning TTFields in the maintenance phase (Maintenance Start Arm). In the intent-to-treat analysis, patients in the Early Start Arm had a median overall survival of 17.7 months versus 17.5 months in the Maintenance Start Arm. The reported hazard ratio was 0.953 with a p-value of 0.519, indicating the difference did not reach statistical significance.
TRIDENT enrolled 981 patients who were randomized shortly after surgical resection. The company reported that early initiation of TTFields was feasible and generally well tolerated, and that no new safety signals emerged during the study. Device-related safety findings were described as consistent with previous clinical studies of TTFields therapy in glioblastoma.
Survival rates at defined timepoints for both arms were disclosed. In the Early Start Arm, one-, two-, and three-year survival rates were 70.9%, 33.9%, and 22.5%, respectively. The Maintenance Start Arm showed one-, two-, and three-year survival rates of 72.0%, 31.6%, and 18.4%, respectively.
Patient demographics and baseline characteristics were reported in the study population. The median age was 60 years. Among participants, 38% had a Karnofsky Performance Status of 70 or 80, 39% carried a methylated MGMT promoter, and 5% had IDH-mutant tumors. The company also noted that about 25% of patients across both arms did not initiate the maintenance phase of treatment.
Novocure said the TRIDENT results have been accepted for presentation at the American Society for Radiation Oncology 2026 Annual Meeting.
Context and implications
While the trial did not demonstrate a statistically significant survival advantage for earlier initiation of TTFields, the study confirmed feasibility and an expected safety profile for the device when started at chemoradiation. The survival rates at one, two, and three years are included for both arms, but the primary endpoint analysis did not meet the threshold for statistical significance.
The trial's enrollment of 981 patients and the subsequent acceptance of the data for presentation at a major radiation oncology meeting underscore the scale and clinical interest in the question of optimal timing for TTFields in newly diagnosed glioblastoma, even as the primary endpoint was not met.