Marshall Edwards prostate cancer drug gains fast track status

The successful application for fast track status was based on data derived from a phase Ib/IIa study, conducted in two Australian hospitals, in which men with late stage hormone-refractory prostate cancer (HRPC) were treated with the oral dosage form of phenoxodiol as a monotherapy.

In the study, dosages of phenoxodiol ranging from 200mg to 400mg eight-hourly had a significant effect on disease progression, as evidenced by falls in PSA levels, and suppression of those levels for a period of at least six months. Most of the patients remain on phenoxodiol therapy for periods up to 18 months without evidence of disease progression.

Of particular relevance to the FDA is that prostatic adenocarcinoma that is refractory to both hormonal therapy and cytotoxic chemotherapy is associated with severe morbidity and a life expectancy of less than one year, and as such meets the criteria for a serious and life-threatening disease.

“This decision of the FDA underpins our confidence in phenoxodiol being an effective therapy for late-stage prostate cancer. The next step is to take phenoxodiol into a pivotal study where we will test its ability to halt disease progression in men with prostate cancer who have failed the standard treatment of hormone therapy and docetaxel chemotherapy,” said Dr Graham Kelly, executive chairman of Marshall Edwards.

Phenoxodiol in intravenous form was granted fast track status by the FDA in November 2004 for its intended use in patients with recurrent ovarian cancer.