Immutep Discontinues Phase III TACTI-004 Trial in NSCLC Following Futility Analysis

Immutep Limited announced the discontinuation of its TACTI-004 (KEYNOTE-F91) Phase III trial evaluating eftilagimod alfa (efti) in first-line non-small cell lung cancer (1L NSCLC). The decision followed a recommendation from the Independent Data Monitoring Committee (IDMC) after a planned interim futility analysis of 170 patients. The analysis revealed that patients in the efti combination arm were underperforming compared to the control arm (pembrolizumab and chemotherapy). Immutep is conducting a root cause analysis to understand the unexpected outcome, which is expected to extend into Q3 CY2026. Consequently, a proposed Phase II trial in breast cancer is on hold. Financially, the discontinuation triggers a US$10 million payment obligation to licensing partner Dr. Reddy’s by June 2026. Despite this, Immutep reported a strong cash position of A$110.6 million as of March 31, 2026, with a cash runway extending into H1 CY2028. Other programs remain active, including the IMP761 Phase I trial in autoimmune diseases, which is progressing to the multiple ascending dose phase with data expected in 2H CY2026.