Testosterone Undecanoate Replacement Therapy in Boys With Pubertal Delay or Confirmed Hypogonadism
The absence of clinical signs of pubertal maturation, i.e. pubertal delay, is a relatively frequent reason for consultation in boys. In cases where it is necessary, the treatment to be established is the administration of testosterone with the aim of provoking the development of secondary sexual characteristics and optimizing growth. Currently, the most commonly used treatment is empirical, with im testosterone enanthate at increasing doses (from 50 mg every 4 weeks up to 250 mg every 4 weeks) over a period of 2 to 3 years. The pharmacokinetic profile has not been described to see if it mimics the physiological progressive increase in testosterone levels occurring during normal puberty. In adults, testosterone enanthate shows supraphysiological serum testosterone the first week after, with a progressive drop to subphysiological levels in the fourth week. Testosterone undecanoate is used in adults at a dose of 1000 mg im every 12 weeks, as equivalent to testosterone enanthate 250 mg every 4 weeks.Serum levels of testosterone show a profile within physiological ranges. Testosterone undecanoate im has not been tested in adolescents. Hypothesis: The hypothesis of this work is that the initial administration of 1 ml (\ 250 mg) of testosterone undecanoate (1000 mg/4 ml) via im every 12 weeks for 6 months, with a progressive increase of 1 ml (\ 250 mg) every 6 months until reaching 4 ml (1000 mg) per dose is safe and effective in causing normal progression of secondary sex characteristics and growth spurt in boys with pubertal delay. The primary specific objectives are to determine, in boys with pubertal delay: (a) if a treatment regimen of testosterone undecanoate (1000 mg/4 ml), with an initial dose of 250 mg every 12 weeks and subsequent increase up to 1000 mg every 12 weeks over 2 years (increasing 250 mg every 6 months) induces a progression in the development of secondary sexual characteristics and growth spurt commensurate with those of normal pubertal development, and (b) the safety of the administration of increasing doses of im testosterone undecanoate.
• Males between 13 and 18 years old without signs of pubertal development, or between 12 and 18 years old with a confirmed diagnosis of anorchia or hypogonadism.
• Normal male configuration of the external genitalia for Tanner G1 stage, with or without palpable testicles, as defined in 4.5.
• As appropriate, assent/consent of the patient and their parents or guardians.