Effect of Tostran 2% Gel on Growth, Development & Bone Turnover in Hypogonadal Adolescent Boys

INTERVENTION: Trade Name: Tostran 2% Gel Product Name: NA Product Code: NA Pharmaceutical Form: Gel INN or Proposed INN: TESTOSTERONE CAS Number: 58220 Concentration unit: % (W/W) percent weight/weight Concentration type: equal Concentration number: 2%‐ CONDITION: Delayed puberty or hypogonadism in boys requiring pubertal induction. ; MedDRA version: 9.1 Level: LLT Classification code 10021011 Term: Hypogonadism male ; MedDRA version: 9.1 Level: LLT Classification code 10043335 Term: Testicular hypogonadism ; MedDRA version: 9.1 Level: LLT Classification code 10052649 Term: Primary hypogonadism ; MedDRA version: 9.1 Level: LLT Classification code 10059594 Term: Secondary hypogonadism ; MedDRA version: 9.1 Level: LLT Classification code 10059597 Term: Central hypogonadism ; MedDRA version: 9.1 Level: HLT Classification code 10014692 Term: Endocrine abnormalities of puberty ; MedDRA version: 9.1 Level: LLT Classification code 10012205 Term: Delayed puberty PRIMARY OUTCOME: Main Objective: Study the effect of Testosterone 2% gel application on pubertal development, growth and bone‐turnover in boys requiring testosterone replacement therapy.; ; Main Outcome Measures; 1. Change in pubertal status; 2. Change in linear growth ; 3. Change in markers of bone formation and resorption; Primary end point(s): Evaluation of primary outcome measures at end of the two treatment periods within the cross‐over study. Secondary Objective: 1. To ensure tolerability; 2. To assess changes in salivary levels of testosterone INCLUSION CRITERIA: Boys who are being started on testosterone replacement therapy for clinical indications. Written informed consent Are the trial subjects under 18? yes Number of subjects for this age range: F.1.2 Adults (18‐64 years) no F.1.2.1 Number of subjects for this age range F.1.3 Elderly (>=65 years) no F.1.3.1 Number of subjects for this age range