Immutep (ASX:IMM) has unveiled a pair of significant clinical developments that underscore its ambition to reshape cancer treatment, announcing positive results in both soft tissue sarcoma and first-line non-small cell lung cancer at the 2025 European Society for Medical Oncology Congress in Berlin.
The company reported that the investigator-initiated EFTISARC-NEO Phase 2 trial evaluating eftilagimod alfa (efti) with radiotherapy and MSD's KEYTRUDA (pembrolizumab) in resectable soft tissue sarcoma (STS) met its primary endpoint, achieving a median 51.5 per cent tumour hyalinization/fibrosis in the evaluable patient population. This represents a more than threefold improvement over historical outcomes from standard radiotherapy alone. Tumour hyalinization is considered an early surrogate for improved survival and recurrence-free outcomes in STS patients.
In a separate presentation, the company revealed new data from the INSIGHT-003 trial in advanced non-squamous first-line NSCLC. The combination of efti with KEYTRUDA and chemotherapy delivered a 61.7 per cent objective response rate in patients with low or no PD-L1 expression (TPS <50 per cent), a group that typically sees lower responses with PD-1 inhibitors alone. This compares with a historical control of 40.8 per cent, marking a meaningful clinical improvement.
These results are expected to inform the pivotal TACTI-004 Phase 3 trial, which is currently enrolling more than 750 patients globally and will assess the same combination across the full spectrum of PD-L1 expression levels.
Immutep’s momentum at ESMO reflects a strategic push to expand its late-stage clinical portfolio and position efti as a foundational component of next-generation immunotherapy combinations.