Immutep (ASX:IMM) has released its annual report, detailing significant progress over the past year with its lead immunotherapy candidate eftilagimod alpha (efti). This drug is designed to activate the body’s immune system to better recognise and attack cancer cells. It targets LAG-3, a protein that plays a key role in regulating immune responses. Specifically, efti stimulates antigen-presenting cells (APCs), which are essential for initiating the body’s immune defence by showing immune cells what to attack.
One of the major trials for efti is the Phase II TACTI-002 trial, conducted in partnership with Merck, which produces the immunotherapy drug KEYTRUDA. KEYTRUDA works by blocking a protein called PD-1 on immune cells, allowing the immune system to fight cancer more effectively. Many cancer cells have a protein called PD-L1, which binds to PD-1, effectively "hiding" them from the immune system. By blocking PD-1, KEYTRUDA exposes cancer cells to immune attack. However, some cancers resist this treatment, so combining KEYTRUDA with efti aims to boost the immune response further.
In the TACTI-002 trial, the combination of efti and KEYTRUDA showed a 71.4% overall response rate (ORR) in patients with non-small cell lung cancer (NSCLC). To put this into context, standard treatment with KEYTRUDA alone typically shows an ORR of around 40.8% in similar patient groups. The combination therapy also led to a median overall survival of 35.5 months in patients whose tumours had at least 1% PD-L1 expression, and 23.4 months for patients with low PD-L1 expression.
These results suggest that adding efti to KEYTRUDA can significantly improve patient outcomes, especially in cancers that are harder to treat with PD-1 inhibitors alone. Immutep is now preparing for a larger Phase III trial, which will evaluate the combination therapy on a broader scale.
With a solid $100m capital raise extending its financial runway through 2026, Immutep is in a strong position to continue advancing its LAG-3 immunotherapy platform.
