Objective: Testosterone replacement therapy is indicated for male hypogonadism. This study aimed to evaluate the efficacy and safety of testosterone gel 2% (Tgel) over 90 days.
Methods: This phase 3, open-label, noncomparator study was conducted in adult hypogonadal men (2 consecutive fasting serum testosterone values <300 ng/dL and >86% subjects with symptoms consistent with testosterone deficiency). Subjects applied Tgel 23 mg/day (single pump-actuation using a hands-free cap applicator). The dose was uptitrated to 46 mg/day after 2 weeks if the 4-hour serum total testosterone level was <500 ng/dL. The dose could be further up- or downtitrated to 23, 46, and 69 mg on Days 21, 42, and 63. The primary endpoint included the percentage of subjects with average testosterone concentration (Cave (0-24)) between 300 and 1,050 ng/dL on Day 90. Safety endpoints were adverse events (AEs), laboratory parameters, and vital signs.
Results: Of the 159 who enrolled, 139 men completed the study. Approximately three-quarters (76.1%) of subjects met Cave criteria on Day 90. Most AEs were mild to moderate. There were 5 serious AEs, and 1 (myocardial infarction) was judged as possibly related to Tgel. Confirmed excessive increases in prostate-specific antigen or hematocrit levels were rare. Tgel had a favorable local skin tolerability profile.
Conclusion: Overall, 76% of subjects achieved Cave between 300 and 1,050 ng/dL with Tgel. Symptoms of testosterone deficiency improved with few safety concerns.
Abbreviations: AE = adverse event Cave(0-24) = average testosterone concentration CI = confidence interval Cmax = maximum concentration IIEF = International Index of Erectile Function MAF = Multidimensional Assessment of Fatigue PK = pharmacokinetic PSA = prostate-specific antigen SAE = serious adverse event SF-12 = Short Form 12 Health Survey Tgel = testosterone gel 2% Tmax = time to achieve maximum concentration TRT = testosterone replacement therapy.