Immutep Limited has announced the discontinuation of TACTI-004, a pivotal Phase III clinical trial investigating eftilagimod alfa (efti) as a first-line treatment for advanced non-small cell lung cancer (NSCLC). According to PharmaBiz.com, the decision follows a recommendation from the trial’s Independent Data Monitoring Committee (IDMC), which determined the study met futility criteria during a planned interim analysis.
The unexpected development marks a significant setback for the Australian biotechnology company’s immunotherapy pipeline. Chief Executive Officer Marc Voigt expressed the company’s disappointment, noting that efti’s performance in TACTI-004 contrasted sharply with results from other clinical evaluations of the drug. “We are very disappointed and surprised with the outcome of the futility analysis, in light of efti’s performance in every other clinical trial,” Voigt stated, while acknowledging the contributions of patients, investigators, and clinical teams.
Trial Design and Scope
TACTI-004 was an ambitious, randomized, double-blind Phase III study designed to evaluate efti combined with Merck’s anti-PD-1 therapy Keytruda (pembrolizumab) and chemotherapy as first-line treatment for advanced or metastatic NSCLC. The trial was planned to enroll approximately 756 patients across over 150 clinical sites in more than 25 countries, regardless of PD-L1 expression status. Patients were randomized 1:1 to receive either the efti-containing combination or pembrolizumab plus chemotherapy with placebo. The study’s dual primary endpoints were progression-free survival and overall survival.
Mechanism and Clinical Significance
Efti represents a novel approach to cancer immunotherapy as a first-in-class MHC Class II agonist. The drug works by directly activating antigen-presenting cells, including dendritic cells and monocytes, thereby engaging both adaptive and innate immune systems. By generating co-stimulatory signals and cytokines, efti aims to enhance the immune system’s capacity to combat cancer while priming and activating cytotoxic T cells. The drug’s favorable safety profile has enabled successful combinations with anti-PD-[L] immunotherapy, radiotherapy, and chemotherapy across various clinical programs.
Program Implications and Next Steps
The discontinuation of TACTI-004 will prompt an orderly wind-down including appropriate patient follow-up and site closure in accordance with regulatory and ethical standards. Immutep is undertaking a comprehensive review of available safety and efficacy data to understand the trial’s outcome and determine the program’s path forward.
The financial implications appear less severe than initially expected. The trial’s cessation will extend Immutep’s previously guided cash runway—set at Q2 2027 before the discontinuation, well beyond this timeframe. However, the company has deferred providing specific updated guidance pending completion of operational assessments and full data analysis.
Broader Program Context
Despite TACTI-004’s disappointment, efti continues evaluation in other solid tumors, including head and neck squamous cell carcinoma, soft tissue sarcoma, and breast cancer. The drug maintains FDA Fast Track designations for first-line treatment of both HNSCC and NSCLC, positioning it as an important asset in Immutep’s diversified immunotherapy portfolio, which leverages the company’s expertise in Lymphocyte Activation Gene-3 (LAG-3) therapeutics.
