GSK’s Phase III study in melanoma fails co-primary endpoint

8th September 2013 (Last Updated September 8th, 2013 18:30)

GlaxoSmithKline's (GSK's) Phase III trial of the MAGE-A3 cancer immunotherapeutic, the DERMA trial, has failed to meet its primary endpoint as it did not extend disease-free survival (DFS) period when compared with placebo in the overall MAGE-A3 positive trial population.

GlaxoSmithKline's (GSK's) Phase III trial of the MAGE-A3 cancer immunotherapeutic, the DERMA trial, has failed to meet its primary endpoint as it did not extend disease-free survival (DFS) period when compared with placebo in the overall MAGE-A3 positive trial population.

The DERMA study, which is a randomised, blinded and placebo-controlled study includes Agenus's QS-21 Stimulon adjuvant, a component of GSK's novel adjuvant system AS15.

The Phase III trial evaluated the efficacy and safety of the MAGE-A3 cancer immunotherapeutic in Stage IIIB/C melanoma patients with macroscopic nodal disease, whose tumours expressed the MAGE-A3 gene and also had their tumours removed surgically.

The MAGE-A3, a tumour-specific antigen, is expressed in about 65% of tumors in Stage III melanoma patients.

GSK intends to continue the DERMA trial until the second co-primary endpoint is assessed and will be in line with the Independent Data Monitoring Committee's (IDMC) unanimous recommendation.

"In the near future, we expect to report results of several other QS-21 Stimulon adjuvant containing programmes."

The co-primary endpoint is designed to identify a subset of MAGE-A3 positive patients that may benefit from the treatment, and results from this analysis are expected to be available in 2015.

Agenus chairman and CEO Garo Armen said: "In the near future, we expect to report results of several other QS-21 Stimulon adjuvant containing programmes."

Agenus expects to report Phase II data for HerpV, a QS-21 Stimulon containing investigational therapeutic vaccine for genital herpes, during the fourth quarter of 2013.

On the other hand, GSK expects to announce Phase III results from MAGRIT, the MAGE-A3 non-small cell lung cancer clinical trial during the first half of 2014 and also provide an update to the RTS,S programme for the prevention of malaria.

Agenus's QS-21 Stimulon adjuvant, a saponin extracted from the bark of the Quillaja saponaria tree, has become essential for several investigational therapeutic vaccines intended to treat cancer and degenerative disorders.