[Treatment of precocious puberty by GnRH agonists].

The objective of GnRH agonist treatment in precocious puberty is to block pubertal development, and to reduce the action of sex steroids on bone maturation in order to restore normal long-term growth of the skeleton. Currently available studies show a positive benefit-risk ratio of GnRH analogs in the treatment of precocious puberty. Adult heights obtained are in average greater than those predicted in the absence of treatment and close to the normal target height. The side effects observed during treatment such as headaches, asthenia or hot flushes, are related to sex steroid deprivation and are observed in 20 to 30% of cases. Questions remain concerning the impact of these treatments on intellectual development and body composition. Finally, to assess the impact on fertility, IPSEN laboratories decided to organize a prospective study on patients treated in the 1980-1990s. In pediatrics, a reduction in the number of injections is an important objective to improve compliance. "Depot" formulations with prolonged release over three months, already used in adult indications, represent a useful progress in pediatrics and have recently been assessed. The efficacy and safety of triptorelin acetate (Decapeptyl) administered at a dose of 11.25 mg every trimester for one year were evaluated in a European multicentre open trial including 54 girls and 10 boys. The LH peak during the GnRH test at three months was used as primary end-point. This slow release triptorelin was shown to be effective, similarly to delayed-acting leuprorelin. The auxological effects, in particular on adult height, were not evaluated in this study.