GTx Inc has entered into tie up with diaDexus Inc, a company statement said. Under the terms of the agreement, GTx will provide clinical samples from its now completed phase IIb clinical trial programme, which evaluated Acapodene (toremifene citrate) tablets for the reduction in the incidence of prostate cancer in men with high grade prostatic intraepithelial neoplasia (PIN), a premalignant lesion that has the potential to progress to prostate cancer.

Acapodene is a nonsteroidal SERM (selective estrogen receptor modulator) that appears to block the estrogen's unwanted actions on the prostate. Information resulting from this collaboration will be evaluated for use by diaDexus for the potential purpose of developing a commercial assay or test from blood or urine to detect high grade PIN and/or prostate cancer.

"High grade PIN identifies patients who are at high risk for developing prostate cancer," stated Mitchell Steiner, CEO of GTx. "The development of assays for the accurate detection of high grade PIN could be a component in the recognition and treatment of this disease," he added.

High grade PIN has been established as a premalignant lesion of the prostate that has a high potential to progress to invasive prostate cancer. There are approximately 7 million men in the US in their 40s and 50s who harbor high grade PIN. These men are thought to be at greater risk for developing prostate cancer within ten years.

This year in the United States, approximately 1,300,000 prostate biopsies will be performed to detect over 230,000 new cases of prostate cancer. High grade PIN is found in an average of 9 per cent of prostate biopsies, which represents an estimated 115,000 new cases of high grade PIN, diagnosed each year. Patients who are found to have high grade PIN are at high risk of prostate cancer with up to 37 per cent of patients being later diagnosed with prostate cancer within 1 year.

Toremifene is a nonsteroidal SERM, a small molecule that binds and selectively modulates the estrogen receptor. SERMs have been shown to block estrogen receptors in the prostate. GTx has licensed the right to develop, market and distribute toremifene citrate, the active ingredient of Acapodene tablets.