(133) ORAL TESTOSTERONE UNDECANOATE QUICKLY AND EFFECTIVELY ACHIEVES SERUM TESTOSTERONE ≥ 300 NG/DL IN MOST HYPOGONADAL MEN WITHOUT DOSE TITRATIONS

Abstract Introduction Over 2.4 million US men have hypogonadism, defined as serum testosterone (T) levels <300 ng/dL and/or symptoms of T deficiency. Negative effects associated with hypogonadism include development of metabolic syndrome, increased risk of coronary artery disease, decreased libido, low bone mineral density, and muscle loss. Oral T replacement therapies provide a route of administration that may be more appropriate for some patients’ needs. Objective We present secondary analyses of T data from a phase 3 study of oral testosterone undecanoate (TU) which is approved in 158, 198, 237, 316, and 396 mg doses, with the goal of demonstrating that the starting oral TU dose quickly and effective achieves normal serum T concentrations in a large proportion of men. Methods A phase 3, randomized, active controlled, open-label study was conducted to assess the safety and efficacy of oral TU in 222 hypogonadal men. Men ≥18 to ≤75 years with morning serum T ≤ 300 ng/dL twice in one week were eligible. Eligible patients were randomized to oral TU or transdermal T-gel from Days 0 to 42. The initial oral TU dose was 237 mg TU twice a day (BID). For men treated with the initial oral TU dose, serum T concentrations were evaluated at Day 21, 4 hours after the dose. Results 165 men had serum T data. 85% of men achieved serum T concentrations ≥300 ng/dL on Day 21 at 4 hours after the first oral TU dose with no dose titrations. (Figure 1) For these 85%, the mean T concentration was 679 ng/dL. Conclusions Overall, the starting dose of 237 mg TU BID quickly and effectively increased serum T concentrations ≥300 ng/dL in 85% of hypogonadal men. The wide distribution of serum T concentrations for the same dose (e.g., 15% <300 ng/d and 12% ≥1000 ng/dL) suggests that men likely respond differently to T replacement therapy. Therefore, an oral T replacement therapy that allows for dose titration would likely be preferable to a fixed dose. Future studies and investigations should evaluate patient factors that impact the magnitude of T increases allowing for more individualized titrations. Disclosure Yes, this is sponsored by industry/sponsor: Tolmar, Inc. Clarification: Industry initiated, executed and funded study. Any of the authors act as a consultant, employee or shareholder of an industry for: Tolmar, Inc.