Immutep reveals initiation of pivotal Efti study

The clinical trial also involves paclitaxel in the treatment of metastatic breast cancer

Immutep – a company which concentrates on developing novel LAG-3 immunotherapies for cancer and autoimmune diseases – has announced the initiation of its AIPAC-003 (Active Immunotherapy, Eftilagimod Alpha and PAClitaxel) study.

The research is an integrated phase 2/3 trial to evaluate eftilagimod alpha – also known as efti – in combination with paclitaxel for the treatment of metastatic HER2-neg/low breast cancer (MBC).

Regulatory approval has already been received in the US, while Institutional Review Board approval has been received in Spain. Meanwhile, approvals in several additional countries are expected to follow imminently. The first patient is due to be enrolled later this year.

Efti is regarded as well positioned to improve clinical outcomes from standard-of-care chemotherapy. Its stimulation of antigen presenting cells, such as dendritic cells and monocytes, instigates a broad immune response that includes increases in cytotoxic CD8+ T cells, combined with chemo-induced tumour antigens to target cancer.

This interaction was shown by the AIPAC phase 2b trial’s encouraging safety and efficacy, including a better median overall survival (mOS) improvement, statistically significant mOS improvements across three pre-specified subgroups and a statistically significant boost in cytotoxic CD8 T cells that correlated with improved OS.

Immutep chief executive officer, Marc Voigt, was encouraged by the results: “With its novel mechanism of action to activate antigen-presenting cells, efti has to date safely improved clinical outcomes from anti-PD-(L)1 therapies and standard-of-care chemotherapy.”

He added: “We look forward to AIPAC-003 building upon the encouraging synergy seen in our previous phase 2b trial in metastatic breast cancer, especially with its three key adaptations: same day administration of efti plus paclitaxel, this dual IO-chemotherapy treatment continuing until disease progression, and a new primary endpoint of overall survival.”

Depending on the phase 2 results, potential regulatory actions and resources, a randomised, double-blinded, placebo-controlled phase 3 element will follow in due course.