title: Testosterone 2% gel can normalize testosterone concentrations in men with low testosterone regardless of body mass index.
abstract: BACKGROUND
  Little is known about the effect of body mass index (BMI) on the efficacy and safety of testosterone therapy in hypogonadal men. A prior noncomparative trial demonstrated that testosterone 2% gel restored testosterone levels in hypogonadal men and was generally well tolerated.
  
  
  OBJECTIVE
  This post hoc analysis evaluated the influence of BMI on the pharmacokinetics of testosterone therapy in men with low testosterone.
  
  
  METHODS
  Men (N = 149) aged 18-75 applied testosterone 2% gel to the front and inner thigh once daily for 90 days. Starting dose was 40 mg/day, which could be adjusted at days 14, 35, and 60. Patients were split into categories depending on baseline BMI: Tertile 1 (≤ 29.1 kg/m(2)), Tertile 2 (29.2-32.4 kg/m(2)), and Tertile 3 (>32.4 kg/m(2)).
  
  
  METHODS
  Efficacy end points were average serum total testosterone concentrations over 24 hours and maximum serum testosterone concentrations at day 90. Adverse events were recorded.
  
  
  RESULTS
  The efficacy analysis included 129 men with low testosterone (mean age 52.9, 54.0, and 54.2 years for Tertiles 1, 2, and 3, respectively) defined as serum testosterone <250-300 ng/dL. Baseline testosterone levels were comparable across BMI tertiles. After 90 days of treatment with testosterone 2% gel (≥ 40 mg/day), 79.1%, 79.5%, and 73.8% of patients in Tertiles 1, 2, and 3, respectively, achieved serum testosterone concentrations in the physiologic range (i.e., ≥ 300 to ≤ 1,140 ng/dL). The mean average daily dose at day 90 was higher in participants in Tertiles 3 vs. 2 (P = 0.039) and Tertiles 3 vs. 1 (P = 0.010). The gel was generally well tolerated, with skin reactions the most commonly reported adverse event (16.1%; n = 24).
  
  
  CONCLUSIONS
  In this study, daily application of testosterone 2% gel was effective at returning serum testosterone to physiologic levels in men with low testosterone and high BMI, although required dose was affected by BMI.
authors.affiliation: Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Adrian
authors.initials: A
authors.lastname: Dobs
authors.forename: Paul
authors.initials: P
authors.lastname: Norwood
authors.forename: Susan
authors.initials: S
authors.lastname: Potts
authors.forename: Errol
authors.initials: E
authors.lastname: Gould
authors.forename: Surya
authors.initials: S
authors.lastname: Chitra
mesh_terms: D000279:Administration, Cutaneous; D000293:Adolescent; D000328:Adult; D000368:Aged; D000728:Androgens / Q000008:administration & dosage* / Q000493:pharmacokinetics; D001823:Body Composition / Q000187:drug effects; D015992:Body Mass Index; D004334:Drug Administration Schedule; D005782:Gels; D006801:Humans; D007006:Hypogonadism / Q000097:blood / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D013739:Testosterone / Q000008:administration & dosage* / Q000097:blood / Q000172:deficiency / Q000493:pharmacokinetics; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000728:Androgens; D005782:Gels; D013739:Testosterone
keywords: Body Mass Index; Hypogonadism; Testosterone Replacement; Transdermal Systemic Testosterone Gel