NEW YORK, April 8 (UPI) -- U.S. medical scientists say two new drugs designed to treat metastatic prostate cancer have shown considerable promise in early clinical trials.
The Howard Hughes Medical Institute researchers said of 30 men who received low doses of one the drugs in a multi-site phase I/II trial designed to evaluate safety, 22 showed a sustained decline in the level of prostate specific antigen in their blood. Phase III clinical trials are planned to evaluate the drug's effect on survival in a large group of patients with metastatic prostate cancer.
The drugs are second-generation anti-androgen therapies that prevent male hormones from stimulating growth of prostate cancer cells. The compounds -- manufactured by the pharmaceutical company Medivation and known as MDV3100 and RD162 -- appear to work well even in prostate cells that have a heightened sensitivity to hormones. That heightened sensitivity makes prostate cancer cells resistant to existing anti-androgen therapies.
The drugs were discovered in the laboratory of HHMI scientist Charles Sawyers at Memorial Sloan-Kettering Cancer Center in collaboration with UCLA chemist Michael Jung.
The development of the drugs and initial testing results appear in the online journal Science Express, in advance of print in the journal Science.