Immutep (ASX:IMM) shares positive data from phase 2b AIPAC trial

• Immutep (IMM) sees a significant increase in innate and adaptive immune response biomarkers in its phase IIb AIPAC trial
• The trial evaluated efti combined with paclitaxel chemotherapy compared to a placebo group in 227 patients with HER2-negative/HR-positive metastatic breast cancer
• IMM says the higher immune response in efti patients compared to placebo patients confirms efti is activating the immune system and improving overall survival
• Immutep is trading 7.58 per cent higher at 35.5 cents

Immutep (IMM) has reported new biomarker and exploratory analysis data from its phase IIb AIPAC trial.

The double-blind and randomised AIPAC trial evaluated efti combined with paclitaxel chemotherapy compared to placebo plus paclitaxel (placebo group) in 227 patients with HER2-negative/HR-positive metastatic breast cancer.

New trial data includes a significant increase in innate and adaptive immune response biomarkers Immutep concluded was sustained throughout the course of the treatment.

Biomarker analysis showed efti, in combination with weekly paclitaxel, significantly increased the number of circulating immune cells and CXCL10 serum levels compared to baseline.

The absolute lymphocyte count (ALC) was shown to increase early on in the patient’s treatment in the efti group, but not the placebo group. Like the increase in biomarkers, the ALC increase was also linked to improved overall survival.

The exploratory analysis revealed that five of the six patient subgroups showed a significant improvement in overall survival in the efti group, compared to placebo.

Furthermore, multivariate analysis showed patients with high body mass index and prior CDK4/6 treatment had much poorer progression-free survival and overall survival outcomes regardless of the therapy they received.

This means high BMI and previous CDK4/6 treatment are considered independent poor prognostic markers and will be considered as stratification factors for future studies.

“The biomarker analysis is highly valuable for two key reasons. Firstly, the statistically significant difference in the immune response between the efti and placebo patients confirms efti is activating the immune system and helping patients live longer,” Chief Scientific Officer and Chief Medical Officer Dr Frederic Triebel said.

“Secondly, the early rise in ALC in patients treated with efti provides clinicians with a potential predictor of improved survival, helping them determine if continued treatment with efti is potentially beneficial,” Dr Triebel said.

Immutep is a globally active biotechnology company that is a leader in developing LAG-3 related immunotherapeutic products for the treatment of cancer and autoimmune disease.

Immutep was trading 7.58 per cent higher at 35.5 cents at 2:29 pm AEST.