Immutep

Clinical research paper describes IMP321’s potency in inducing progression-free survival improvement and effector memory T cells

Immutep S.A. announced today the publication of a clinical research paper showing that its lead product, IMP321, improved progression-free survival in advanced renal cell carcinoma patients.

The single-centre open-label dose-escalation Phase I study was carried out at the Institut Gustave Roussy (IGR, Villejuif, France), the largest cancer clinic in Europe, under the supervision of Dr Bernard Escudier, a leading specialist in renal cell carcinoma. The immuno-monitoring was done by Immutep at its laboratories near Paris.

Twenty-one advanced RCC patients received 119 injections of IMP321 at doses ranging from 0.050 to 30 mg/injection s.c. biweekly for 6 injections. No clinically significant adverse events were observed. Good systemic exposure to the product was obtained following s.c. injections of doses above 6 mg. IMP321 induced both sustained CD8 T cell activation and an increase in the percentage of long-lived effector-memory CD8 T cells in all patients at doses above 6 mg. Tumour growth was reduced and progression-free survival was better in those patients receiving higher doses (>6 mg) of IMP321: 7 out of 8 evaluable patients treated at the higher doses experienced stable disease at three months compared to only 3 out of 11 in the lower dose group (p=0.015).

The absence of toxicity and the demonstration of activity warranted further studies of IMP321 in combined regimens (e.g. chemo-immunotherapy). Further improving the CD8 memory T cell response seen in the present study by extending the treatment schedule of biweekly injections from 3 months to 6 months may also improve the clinical outcome. To this end, two such chemo-immunotherapy trials are in progress in metastatic breast cancer and advanced pancreatic cancer in which IMP321 is given the day after first-line paclitaxel and gemcitabine, respectively.

Published 09/2009 by admin@immutep.com