FDA approves treatment for advanced prostate cancer

Ferring Pharmaceuticals, USA has received FDA approval to market degarelix, an injectable gonadotropin-releasing hormone (GnRH) receptor antagonist, indicated for patients with advanced prostate cancer.

Phase III studies showed that degarelix is at least as effective as leuprolide (Lupron Depot) in sustaining castrate levels or lower of testosterone, and had a statistically significant faster reduction of testosterone. At day 3 of treatment, 96% of degarelix patients achieved castrate levels of testosterone, compared with 0% receiving leuprolide. By day 14, 99% of degarelix patients achieved castrate levels of testosterone, compared with 18% receiving leuprolide, according to Ferring.

In the trial, PSA levels were lowered by 64% 2 weeks after administration of degarelix, 85% after 1 month, 95% after 3 months, and remained suppressed throughout the 1 year of treatment. PSA results should be interpreted with caution, a Ferring release said, because of the heterogeneity of the patient population studied. No evidence has shown that the rapidity of PSA decline is related to a clinical benefit, the company said.

Degarelix achieves medical castration differently than LHRH agonists, specifically by binding reversibly to GnRH receptors on cells in the pituitary gland, quickly reducing the release of gonadotropins and, consequently, testosterone.

“Use of a GnRH receptor antagonist is a highly efficient way to stop the production of testosterone,” said Neal Shore, MD, of Carolina Urologic Research Center, Myrtle Beach, SC. “The approval of degarelix offers the medical community an effective alternative in the treatment of hormonally sensitive prostate cancer. Now prostate cancer can be treated with immediate inhibition of the GnRH receptors, inducing rapid reduction of testosterone to castrate levels, and sustaining those levels over time, which are the goals of systemic therapy.”