Efficacy and Safety of Triptorelin 3-Month Formulation in Chinese Children with Central Precocious Puberty: A Phase 3, Open-Label, Single-Arm Study

INTRODUCTION: Triptorelin is available as 1- and 3-month prolonged-release (PR) formulations; at the time of the study, only the former was approved for central precocious puberty (CPP) in China. This study assessed the efficacy and safety of the triptorelin 3-month PR formulation in Chinese children with CPP. METHODS: In this 12-month, prospective, open-label, multicentre, single-arm study (NCT04736602), Chinese children (mean age [standard deviation (SD)], 7.6 ± 0.8 years) with CPP received triptorelin pamoate 15 mg on day 1 and at months 3, 6 and 9. The primary endpoint was the proportion with luteinizing hormone (LH) suppression (stimulated peak LH ≤ 3 IU/L after gonadotropin-releasing hormone [GnRH] stimulation) at month 3. Secondary endpoints included changes from baseline in hormone levels and clinical parameters, as well as safety assessments. RESULTS: Overall, 32 children were enrolled, including three boys. LH suppression to prepubertal levels (≤ 3 IU/L) after GnRH stimulation was observed in 100%, 93.5% and 93.5% of participants at months 3, 6 and 12, respectively. Basal and peak LH and follicle-stimulating hormone levels were substantially suppressed at months 3, 6 and 12, and most participants showed sex hormone suppression. At months 6 and 12 respectively 92.9% and 89.3% of girls had stable breast development, and all boys had stable genital development. There was a decrease in mean growth velocity from baseline (8.96 cm/year) to months 3, 6 and 12 (8.07, 5.24 and 6.94 cm/year, respectively). The mean difference between bone and chronological age decreased from baseline (2.85 years) to month 12 (2.39 years). In girls, uterine length was stable or reduced at month 12; in boys, testicular volume was reduced. Triptorelin was well tolerated. CONCLUSION: The triptorelin 3-month PR formulation demonstrated similar efficacy to that previously reported in non-Chinese patients with CPP and had an acceptable safety profile. This supports triptorelin 3-month PR as a viable option for Chinese children with CPP.