The trial is being conducted by Merck and its US affiliate EMD Pharmaceuticals pursuant to the terms of a collaboration. Merck obtained the exclusive worldwide licensing rights for Stimuvax from Biomira.
The trial will evaluate patients with documented unresectable stage III non-small cell lung cancer (NSCLC) who have had a response or stable disease after at least two cycles of platinum based chemo-radiotherapy. Currently, there are no approved maintenance therapies for patients responding to first-line treatment for unresectable stage III NSCLC.
Stimuvax is designed to induce an immune response to cancer cells that express MUC1, a protein antigen widely expressed on common cancers. MUC1 is over expressed on many cancers such as lung cancer, breast cancer and colorectal cancer. Stimuvax is thought to work by stimulating the body's immune system to identify and destroy cancer cells expressing MUC1.
Overall study results from an earlier phase IIb trial were not statistically significant. But Stimuvax showed a median survival of 30.6 months versus 13.3 months in the control group – an improvement of 17.3 months.