Background:In central precocious puberty (CPP),the pulse secretion and release ofgonadotropin-releasing hormone (GnRH) are increased due to early activation of the hypothalamic-pituitary-gonadal axis,resulting in developmental abnormalities with gonadal development and appearance of secondary sexual characteristics.The CPP without organic disease is known as idiopathic CPP (ICPP).The objective of the study was to evaluate the clinical efficacy and safety of domestic leuprorelin (GnRH analog) in girls with ICPP.Methods:A total of 236 girls with ICPP diagnosed from April 2012 to January 2014 were selected and were randomized into two groups.One hundred fifty-seven girls in the test group were treated with domestic leuprorelin acetate,79 girls in the control group were treated with imported leuprorelin acetate.They all were treated and observed for 6 months.After 6-month treatment,the percentage of children with peak luteinizing hormone (LH) ≤3.3 U/L,the percentage of children with peak LH/peak follicle stimulating hormone (FSH) ratio ＜0.6,the improvements of secondary sexual characteristics,gonadal development and sex hormone levels,the change of growth rate of bone age (BA) and growth velocity,and drug adverse effects between two groups were compared.Results:After the treatment,the percentage of children with a suppressed LH response to GnRH,defined as a peak LH ≤3.3 U/L,at 6 months in test and control groups were 96.80％ and 96.20％,respectively,and the percentage of children with peak LH/FSH ratio ≤0.6 at 6 months in test and control groups were 93.60％ and 93.70％,respectively.The sizes of breast,uterus and ovary of children and the levels of estradiol (E2) were significantly reduced,and the growth rate of BA was also reduced.All the differences between pre-and post-treatment in each group were statistically significant (P ＜ 0.05),but the differences of the parameters between two groups were not significant (P ＞ 0.05).Conclusions:Domestic leuprorelin is effective and safe in the treatment of Chinese girls with ICPP.Its effectiveness and safety are comparable with imported leuprorelin.