Enclomid and Topical Testosterone Elevate Testosterone in Hypogonadal Men but Enclomid Does Not Decrease Testes Size

Program: Abstracts - Orals, Poster Previews, and Posters
Session: SAT 116-136-Male Hypogonadism - Causes and Treatments
Saturday, March 7, 2015: 1:00 PM-3:00 PM
Hall D-F, Reproductive Endocrinology (San Diego Convention Center)

Poster Board SAT-124
Ronald Wiehle, PhD1, Gregory Fontenot, PhD2, Jennifer Nydell, BS1, Jaye Thompson, PhD1, Martin Sandel, MS1 and Andrew McCullough, MD, FACS3
1Repros Therapeutics, The Woodlands, TX, 2Repros therapeutics, The Woodlands, TX, 3Urological Institute of Northeastern New York, Albany, NY
Introduction and Objective: It was our aim to evaluate oral enclomid (enclomiphene citrate or Androxal) as an alternative to a currently-available topical testosterone replacement therapy for men with secondary hypogonadism.

Methods:These trials (ZA-304 and ZA-305) were randomized, double blind, placebo- and active-control, multi-center phase III studies in 224 men between 25 and 60 years of age with secondary hypogonadism. Men received 12.5mg or 25mg of enclomid as a daily capsule and were provided with a placebo gel.  Other men received AndroGel 1.6% and placebo capsules.  Placebo men received placebo capsules and gels.

Results: Subjects needed to have initial testosterone (T) values below 300ng/dL at least twice. At End of Study (EOS), 16 weeks, there was a statistically significant rise in T in men receiving either enclomid or topical testosterone product into the normal range (see table). Placebo subjects did not change. Enclomid did not decrease sperm counts unlike the topical gel. As we have seen before, enclomid increased LH and FSH while men in the topical arm showed decreases (not shown). All men were similar at baseline in testes volume (p=0.94, ANOVA) by orchidometry. Men on topical testosterone demonstrated decreases in mean testicular volume (-0.86 cm3) in both studies and a significant decrease overall compared to the enclomid (p<0.05) or placebo (p<0.05).

Conclusions: Enclomid led to no deleterious effects on sperm counts or testes size by orchidometry.  It also significantly increased total serum testosterone, LH and FSH which suggests that the drug normalized endogenous testosterone production through the hypothalamic-pituitary-testicular axis and supported the natural continuation of sperm number and testes volume.     Supported by Repros Therapeutics Inc.

Disclosure: RW: Chief Scientific Officer, Repros Therapeutics. GF: Researcher, Repros therapeutics. JN: Management Position, Repros Therapeutics. JT: Board Member, Repros Therapeutics, Employee, Repros Therapeutics. MS: Employee, Repros Therapeutics. AM: Coinvestigator, Repros Therapeutics, Medical Advisory Board Member, Repros Therapeutics.

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