Immutep has reported positive final data from Part B of the TACTI-002 Phase II trial in second line metastatic non-small cell lung cancer (NSCLC) patients refractory to anti-PD-(L)1 therapy.

The results showed that all the 36 patients, who took part in the trial, demonstrated progression after standard of care first line treatment with anti-PD-X therapy.

This included 67% of the patients who received anti-PD-X therapy and chemotherapy. This figure rose to 72% when non-evaluable patients were excluded.

In these PD-X refractory, 2L metastatic NSCLC patients, the chemo free combination of efti plus pembrolizumab attained 9.9 months of median Overall Survival (mOS) and a 39% OS rate at 21 months, which compare positively to the usual six to nine months mOS and a 10-15% OS rate at 21 months for standard-of-care chemotherapy.

It was also found that the combination of efti and pembrolizumab was well tolerated by the patients with no new safety signals observed.

In addition, Immutep conducted tumour growth kinetics (TGK) analysis based on the difference of the sum of the largest diameters of target lesions in the pre- and post-baseline context on patients.

The analysis found that 83.3% of patients showed decrease or deceleration of tumour growth.

A total of 36%, 39%, and 16.7% of patients had a PD-L1 tumour proportion score (TPS) of less than 1%, 1-49%, and more than 50%, respectively, while 8.3% of patients could not evaluated for PD-L1 expression.

Immutep CEO Marc Voigt said: “These encouraging results and overall survival trends in patients refractory to PD-1/PD-L1 containing therapy, which have confirmed progression via two consecutive scans, offers a potential therapeutic pathway for many in dire need of new options.”