Immutep Limited (ASX: IMM), a clinical-stage biotechnology company, has announced positive data from its INSIGHT-003 Phase I trial, showcasing significant survival benefits in non-squamous non-small cell lung cancer (NSCLC). This data strengthens the potential of eftilagimod alpha (efti), an innovative immunotherapy, in combination with KEYTRUDA® (pembrolizumab) and chemotherapy.

Exceptional Survival Outcomes with Efti Combination Therapy

The INSIGHT-003 trial has delivered promising results with mature data from patients having a minimum follow-up of 22 months (N=21). Key highlights include:

• Median Overall Survival (OS): 32.9 months
• Median Progression-Free Survival (PFS): 12.7 months
• 24-month Overall Survival Rate: 81.0%

These results significantly outperform historical controls, where median OS was 22.0 months, median PFS was 9.0 months, and the 24-month OS rate stood at 45.5%.

Improved Response Rates Across PD-L1 Levels

Data from 40 evaluable patients indicate a notable improvement in Overall Response Rate (ORR) across all levels of PD-L1 expression when compared to historical controls:

• High PD-L1 Expression (TPS >50%): 75.0% ORR (vs. 62.1% historical)
• Low PD-L1 Expression (TPS 1-49%): 58.8% ORR (vs. 49.2% historical)
• Negative PD-L1 Expression (TPS <1%): 47.4% ORR (vs. 32.3% historical)

In patients with low and negative PD-L1 expression (N=36), the combination achieved a 52.8% ORR and 86.1% Disease Control Rate (DCR).

Favorable Safety Profile

Safety data from INSIGHT-003 confirm a favorable profile for efti in combination with pembrolizumab and chemotherapy. There were no new safety signals, reinforcing the potential of efti as a viable addition to standard treatments.

Expert Insights and Future Outlook

Professor Salah-Eddin Al-Batran, the project lead, highlighted the trial's promising outcomes, especially in patients with negative or low PD-L1 expression, a population typically less responsive to anti-PD-1 therapies.

Marc Voigt, CEO of Immutep, emphasized, “These results exceed our expectations and bolster our ambition to establish a new standard of care in first-line NSCLC treatment. As we prepare for the TACTI-004 Phase III trial, we remain focused on leveraging efti’s complementary effects to improve patient outcomes globally.”

Next Steps for INSIGHT-003 and Beyond

INSIGHT-003 is nearing completion of patient enrollment, with additional data updates expected in 2025. The upcoming TACTI-004 Phase III trial will further evaluate the efficacy of efti in a similar patient population, with dual primary endpoints of PFS and OS.

About Immutep and Eftilagimod Alpha

Immutep is a leader in the development of novel LAG-3 immunotherapies for cancer and autoimmune diseases. Eftilagimod alpha, a unique MHC Class II agonist, is designed to stimulate the immune system and enhance the efficacy of existing treatments. Its potential has been demonstrated in multiple trials, including the groundbreaking INSIGHT-003 study.

For further information, contact Immutep’s investor relations team or visit the company’s website.