New estrogen inhibitor in phase II development.

2004 MAR 4 - (NewsRx.com & NewsRx.net) -- Ascend Therapeutics, Inc., announced that it has obtained exclusive North American development, marketing and commercialization rights to the developmental pharmaceutical product, TamoGel (4-hydroxytamoxifen gel), a new estrogen inhibitor under investigation for a variety of estrogen-dependent conditions, including cyclic breast pain and gynecomastia.

TamoGel is formulated using Enhanced Hydroalcoholic Gel (EHG) Technology. This technology enables percutaneous delivery of drugs that cannot be delivered orally.

TamoGel is an example of how a patient-friendly percutaneous gel can deliver the clinical promise of undeveloped molecules. 4-hydroxytamoxifen, the active ingredient in TamoGel, is a potent estrogen inhibitor that cannot be taken orally due to high first-pass liver metabolism. The use of the innovative EHG technology as a delivery vehicle for 4-hydroxytamoxifen has enabled the clinical development of this promising, but previously undeveloped molecule, now in phase II trials. TamoGel, along with its intellectual property, was acquired by Ascend from Besins International Holdings, the leading manufacturer of prescription gels in the world.

"We are very pleased to announce the acquisition of TamoGel," noted Jay Bua, CEO of Ascend Therapeutics, "as we firmly believe that we have the potential to create a standard of care for two large areas of unmet medical need: cyclic breast pain in premenopausal women and gynecomastia in men receiving therapy for prostate cancer. Both of these conditions are estrogen-dependent diseases of the breast."

TamoGel is a percutaneously applied gel formulation of the anti-estrogen 4-hydroxytamoxifen (4-OHT), the most active metabolite of tamoxifen. 4-OHT has been shown to be up to 100 times more potent than tamoxifen in inhibiting breast cancer cell proliferation in vitro. 4-OHT cannot be delivered orally, however, because it is rapidly inactivated by the liver following oral administration.

Using EHG Technology, 4-OHT has been formulated for transdermal delivery as a gel. The gel is applied daily by the patient to the surface of the breast. The EHG gel is fast-drying (less than 2 minutes), non-greasy and can easily be incorporated into morning hygiene habits. EHG Technology enhances the penetration of 4-OHT into the skin and allows the skin itself to become the reservoir of drug release.

EHG is a proven technology that is currently used in AndroGel, the leading testosterone replacement therapy in the world. EHG Technology effectively creates an "invisible patch" that patients can apply almost anywhere on the body. Unlike transdermal patches, which need to be concealed and can cause skin irritation, EHG gels are completely invisible after drying. The advantages of percutaneous administration of 4-OHT include avoidance of first-pass liver metabolism, greater bioavailability and the ability to target the desired tissue/area of medical need. Local, transdermal application of TamoGel may be able to provide adequate tissue concentration of 4-OHT while keeping systemic levels low, thus avoiding unwanted side effects.