Androxal (enclomiphene) boosts sperm count in low testosterone men: Repros

Repros’ Androxal is also found raising male sex hormone testosterone in men

Enclomiphene citrate (Androxal) could significantly increase sperm counts while increasing testosterone levels in men, claims its producers Repros Therapeutics Inc.

Enclomiphene citrate (Androxal) has been studied for its efficacy and safety study  in men with secondary hypogonadism who were receiving testosterone replacement treatment.

Secondary hypogonadism is a deficiency state in which the male hormone testosterone goes below the normal range, even in aging men, due to inadequate stimulation of the testes by the pituitary.

Repros compared its oral formulation enclomiphene citrate (Androxal) to an approved topical testosterone gel Testim 1% by Auxilium Pharmaceuticals Inc, indicated for testosterone replacement therapy in adult males for conditions associated with a deficiency or absence of endogenous testosterone.

Repros conducted the two-center, three-arm, randomized, open-label, fixed dose, active-control, proof-of-principle study in men between 46 and 51 years of age who were treated previously with a topical testosterone gel.

Study results found that Androxal consistently elevated sperm counts into the normal range after 3 and 6 months of treatment and at follow-up.

Testim resulted in sperm counts below 20 x 106/ml (the level below which a man would be considered infertile) for all 5 men at 3 months. At 6 months, 3 of the 5 Testim treated men remained well below the 20 x 106/ml level exhibiting little to no detectable sperm count, whereas the other two showed levels > 20 x 106/ml.

The sperm count was statistically significantly higher in the Androxal than the Testim treated group at 3 and 6 months.

Androxal was also found increasing both leutenising hormone (LH) and follicle stimulating hormone (FSH) while men on Testim had significantly lower levels of these important fertility related hormones.

Androxal has already been demonstrated effective in LH and FSH in a long term study for over a year in men with secondary hypogonadism.

New Androxal study confirms that testosterone levels can be normalized through endogenous testosterone while fertility is restored, Repros reported.

“Androxal may fill the need for a drug that is able to restore testicular function and at the same time provide the benefits that normalization of testosterone provides to hypogonadal men,” said Dr. Jed Kaminetsky (Department of Urology, New York University Medical Center), the lead investigator in an official release.

Treatment with Androxal and Testim was well tolerated in this study, with few side effects being reported.

Repros plans to submit a request for a meeting to US FDA to determine whether the agency deems these observations to be clinically relevant and whether a development program can be designed to confirm the findings of this exploratory study, and ultimately support a label for the treatment of secondary hypogonadism in men who wish to preserve their fertility.

In September, US FDA asked for additional data on Repro’s lead drug Proellex, to resolve the clinical hold placed on it, due to safety reasons.

Proellex is a selective blocker of the progesterone receptor and previously was primarily being developed for the chronic treatment of symptoms associated with uterine fibroids and endometriosis.

In 2008 Repros filed an Investigational New Drug application (IND) for Proellex for a new indication as a three-month pre-surgical treatment for women with anemia due to excessive menstrual bleeding associated with uterine fibroids.

On August 3, 2009, Repros Therapeutics announced it voluntarily suspended dosing of all patients in its clinical trials of Proellex.

Topical testosterone use has been associated with suppression of pituitary gonadotrophic hormones, luteinizing hormone (LH) and follicle stimulating hormone (FSH), both necessary for stimulating testosterone production and spermatogenesis in the testes.

Androxal is an oral therapy intended to restore normal brain-pituitary-testes interaction and thus testicular function in men with secondary hypogonadism.

Based in the Woodlands, Texas, Repros Therapeutics focuses on the development of oral small molecule drugs  that treat male and female reproductive disorders.