The men’s health company GTx has announced two sets of of interim results in the past month from its pivotal Phase III clinical trial of Acapodene (toremifene citrate) for the treatment of side effects of androgen deprivation therapy (ADT) for prostate cancer.

Androgen deprivation therapy (ADT) for prostate cancer decreases the natural hormone called testosterone. While some men with prostate cancer avoid this treatment altogether and some take it for just a few months, many men with aggressive or advanced disease remain on ADT, continuously or intermittently, for years.

Men on ADT men may experience multiple side effects. These may include hot flashes, painful breast swelling, changes in their cholesterol levels and thinning of the bones with increased risk of fractures.

GTx is conducting a pivotal Phase III clinical trial of Acapodene (toremifene citrate) for the treatment of side effects of androgen deprivation therapy. Approximately 1,400 men are enrolled at over 150 sites in the United States and Mexico.

The main purpose of the study is to determine whether or not the addition of toremifene citrate to therapy can prevent or decrease the number of bone fractures and to evaluate its impact on side effects associated with testosterone reduction therapy.

Toremifene citrate (trade name Acapodene) is a selective estrogen receptor modulator, or SERM, consisting of a small molecule that binds to and selectively modulates estrogen receptors. These molecules have the ability to either stimulate or block estrogen’s activity in different types of tissue:

* Stimulate estrogen’s beneficial action in bone
* Block estrogen’s harmful activity in the breast
* Block estrogen’s harmful activity in the prostate
* Potentially block hot flashes in men

The benchmark goal (or primary endpoint) of the pivotal Phase III clinical trial of Acapodene is a reduction in vertebral fractures. Secondary endpoints include improvements in bone mineral density (BMD), hot flashes, gynecomastia, and lipid profiles.

Final data from this trial, which is being conducted under a Special Protocol Assessment with the United States Food & Drug Administration, is expected in the second half of 2007.

Meanwhile GTx has announced promising interim analysis results for the effect of Acapoden on bone mineral density and on cholesterol and High density lipids (HDL).

Rise in cholesterol associated with ADT is of special concern not only because it elevates the risk of cardiovascular problems but also because prostate cancer has been linked to high cholesterol.

Bone density loss (loss or thinning of the bones) can lead to osteoporosis and fractures of hip and spine. On average, prostate cancer patients on ADT who develop bone fractures have a shorter life expectancy.

GTx is currently recruiting patients for just one trial:
Prostate Cancer Prevention Study for Men With High Grade PIN (Prostatic Intraepithelial Neoplasia)

Other Gtx trials are filled up. You might want to look them over to see what’s in the pipeline.

Potentially this class of drugs could make life a lot easier for prostate cancer patients who require and/or choose to take androgen deprivation therapies.

GTx website page on SERM’s is here.