[Treatment of precocious puberty with an LH-RH agonist (D-TRP6-LH-RH)]

Chronic administration of luteinizing hormone-releasing hormone (LH-RH) is currently considered as the most appropriate therapy of precocious puberty. A delayed release preparation of D-Trp-6-LH-RH (Décapeptyl in microcapsules) designed to release the agonist for 28 days after intramuscular injection of 60 micrograms/kg body wt was given to 12 boys and 26 girls with precocious puberty. Plasma levels of gonadotropins and sex steroids were suppressed to prepubertal levels within 3 weeks, whilst pituitary responses to LH-RH test were almost abolished within 7 weeks. A significant improvement of secondary sex characteristics, as well as gonadal size, was observed within 6 months. Growth velocity (cm/yr, mean +/- SD) was reduced in boys and girls from 9.9 +/- 3.4 and 9.6 +/- 3.3 respectively before treatment to 5.2 +/- 1.0 and 5.3 +/- 1.3 respectively during the third year of treatment. The mean ratio height age/bone age was just before treatment 0.91 in boys and 0.88 in girls and increased to 1 after 3 yr of treatment. This study shows that Décapeptyl in microcapsules induced a prolonged suppression of gonadal function and a relative blockade of bone maturation. A significant improvement of adult height relative to the effect of conventional treatments should be expected.