Immutep's Independent Data Monitoring Committee recommended discontinuing the Phase III TACTI-004 trial after a planned interim futility analysis determined the study was unlikely to meet its primary endpoints of overall survival and progression-free survival23.
The trial was evaluating eftilagimod alfa (efti), a LAG-3 fusion protein designed to activate antigen-presenting cells, in combination with Merck's Keytruda (pembrolizumab) as a first-line treatment for advanced or metastatic non-small cell lung cancer12.
Immutep's stock plummeted approximately 88.60% on the announcement, falling from around $0.395 to $0.047, with some reports indicating an 80% drop in premarket trading12.
The trial failure was unexpected given efti's positive performance in previous clinical studies, including a Phase 2b trial in head and neck cancer that demonstrated a 35.5% objective response rate13.
CEO Marc Voigt stated the company was "very disappointed and surprised" by the results and announced Immutep would conduct a comprehensive review of available data to determine next steps for the program14.
TACTI-004 was Immutep's primary value driver in its pipeline, and the discontinuation removes the company's most significant commercial prospect2.
The broader LAG-3 development field has experienced mixed results, with many attempts to improve upon existing checkpoint inhibitor treatments failing in late-stage trials2.
Sources:
1. https://www.fiercebiotech.com/biotech/immuteps-phase-3-failure-immunotherapy-surprises-analysts-sinks-stock
2. https://kalkine.com.au/news/general-news/immutep-asximm-stock-crashes-8860-after-phase-iii-trial-failure-what-investors-need-to-know
3. https://www.clinicaltrialsarena.com/news/immutep-efti-phase-iii-frontline-nsclc-trial-discontinuation-tacti-004/
4. https://pharmaphorum.com/news/immutep-investors-spooked-lag-3-failure-lung-cancer