Cancer drug developer Antisoma has reported preliminary data from a Phase II trial of its AS1404 compound indicating that it has activity in men with hormone-refractory prostate cancer.

Antisoma hopes that the new data will help it ongoing efforts to find a licensing partner for AS1404 (DMXAA), a vascular disrupting agent that was formerly partnered with Roche.

The initial findings show that AS1404 given alongside the chemotherapy agent docetaxel achieved a clinically-significant reduction in levels of prostate-specific antigen (PSA) – a biomarker for prostate cancer – in 57% of patients. This response was seen in 35% of patients given docetaxel alone.

In addition, the proportion of men showing disease progression measured by PSA levels was almost halved in the AS1404 group (17% versus 29% with docetaxel alone).

The findings are a milestone for Antisoma because they back up the efficacy of AS1404 in response rates and disease progression that has already been shown in patients with lung cancer, and indicate that the drug could have utility in multiple indications. The company also reported initial positive data from a Phase II trial in ovarian cancer earlier this year.