Immutep Expands Part B of TACTI-002 Study

Immutep has decided to expand Part B of its TACTI-002 Phase II trial, under the study’s Simon’s two- stage clinical trial design. Immutep has commenced recruitment of an additional 13 second line Non-Small Cell Lung Cancer (NSCLC) patients, forming Stage 2 of Part B.

The decision follows a preliminary safety and efficacy review by the Data Monitoring Committee and its recommendation, based on the patients recruited in Stage 1 of Part B.

TACTI-002 (Two ACTive Immunotherapies) is being conducted in collaboration with Merck, Kenilworth, NJ, USA (known as MSD outside the United States and Canada). The study is evaluating the combination of efti with MSD’s KEYTRUDA® (pembrolizumab) in patients with second line head and neck squamous cell carcinoma or non-small cell lung cancer in first and second line.

The trial is a Phase II, Simon’s two-stage, non-comparative, open-label, single-arm, multicenter clinical study that is taking place in up to 12 study centers across Australia, Europe, the UK and US.

Patients participating in three parts:

• Part A - First line Non-Small Cell Lung Cancer (NSCLC), PD-X naive

• Part B - Second line NSCLC, PD-X refractory

• Part C - Second line Head and Neck Squamous Cell Carcinoma (HNSCC), PD-X naive

TACTI-002 is an all-comer study in terms of PD-L1 status, a well-known predictive marker for response to pembrolizumab monotherapy especially in NSCLC and HNSCC. PD-L1 expression is typically reported in three groups for NSCLC: < 1%, 1-49% and ≥ 50% (Tumor Proportion Score or TPS) and in HNSCC: < 1%, 1- 19% and ≥ 20% (Combined Positive Score or CPS). Patients with a high PD-L1 status are typically more responsive to anti-PD-1 therapy such as pembrolizumab, whereas those with low PD-L1 status are overall significantly less responsive. Pembrolizumab monotherapy is registered in the US and the EU for first line NSCLC patients with a TPS score ≥ 1% (US) and ≥ 50% (EU), reflecting 65% and 30% of all first line NSCLC patients, respectively. Pembrolizumab monotherapy is registered in the US (regardless of PD-L1 expression) and EU (≥ 50% TPS score) for second line HNSCC patients.