GTx and Gen-Probe to Study the Ability of Research-Stage Diagnostic Test to Detect High Grade PIN

Jan. 31, 2006:

"/PRNewswire-FirstCall/ -- GTx, Inc. (Nasdaq: GTXI), the Men's Health Biotech Company, today announced that it has entered into an exploratory collaboration with Gen-Probe, Incorporated (Nasdaq: GPRO) to evaluate the ability of Gen-Probe's research-stage PCA3 assay to detect high grade prostatic intraepithelial neoplasia, or PIN. High grade PIN is the precancerous lesion of the prostate.

Clinical studies have shown that men with high grade PIN are at high risk for prostate cancer. Today high grade PIN can only be diagnosed by prostate biopsy. There are 1.1 million men in the U.S. with biopsy confirmed high grade PIN, with 115,000 new cases diagnosed each year. Yet, it is estimated that that there are 15 million men in the U.S. who unknowingly harbor the condition. The ability to identify high grade PIN through a non-invasive diagnostic test may allow more patients to find out whether they are at high risk for prostate cancer.

Under terms of the agreement, GTx will provide Gen-Probe with urine samples from patients enrolled in GTx's clinical trials testing ACAPODENE(R) (toremifene citrate 20mg) for the prevention of prostate cancer in men with high grade PIN: a completed Phase IIb trial of 514 patients and an ongoing large pivotal Phase III trial in 1,260 men with high grade PIN at more than 130 sites in the United States, Canada, Mexico and Argentina. Gen-Probe will evaluate the samples from this special patient cohort with its research-stage test for PCA3 gene expression. PCA3 has been shown to be highly over-expressed in malignant prostate cells. Its pattern of expression may help identify a high grade PIN subpopulation."

This one may not be disclosed, but if it is, perhaps in the 10-Q for the first quarter - in early May?