“While prostate cancer growth is driven by androgens like testosterone, current anti-androgen therapies do not stop the growth of hormone-refractory prostate tumors.
“These preclinical findings with MDV3100 are extremely promising because MDV3100 not only dramatically inhibited the growth of otherwise refractory human prostate tumors, but in half of the cases the tumors regressed,” said Dr Sawyers, chairman of the Human Oncology and Pathogenesis Program at Memorial Sloan-Kettering Cancer Center in New York.
Results of the research showed that MDV3100 treatment was associated with a significant dose-dependent reduction in tumor volume in human hormone-refractory prostate tumors grown in mice. When left untreated, these human tumors approximately doubled in volume over a 28-day period.
By contrast, treatment with MDV3100 over the same period caused these tumors to shrink. Most notably, in the high-dose group, tumor volume was reduced to non-measurable levels in three of seven animals.
“We are very encouraged by these preclinical results and are planning to initiate a US phase I-IIa trial in patients with hormone-refractory prostate cancer in the first half of this year,” said David Hung, president and CEO of Medivation.
“If that trial shows MDV3100 to be tolerated and to inhibit serum prostate-specific antigen levels, we expect to proceed directly to phase III clinical trials in hormone-refractory prostate cancer.”