SAT-228 - Long-Term Real-World Evidence of Clinical Suppression with 6-Month Subcutaneous Leuprolide Acetate in Children with Central Precocious Puberty

Gonadotropin-releasing hormone agonists (GnRHa) are the gold-standard treatment for central precocious puberty (CPP). Approved by the FDA in 2020, 6-month 45mg subcutaneous leuprolide acetate (SC-LA, FENSOLVI®) is the first LA therapy with a polymeric gel delivery system and a small injection volume. Phase 3 data demonstrated SC-LA to be an effective, safe, and convenient treatment option for CPP; however, long-term efficacy and safety data remain limited. The objective of this retrospective real-world database review is to assess long-term clinical suppression with SC-LA in children with CPP.

This multi-site retrospective study evaluated the real-world use of 6-month SC-LA for the treatment of CPP. Anonymized electronic data from patient medical records at enrolled sites are being collected. This interim analysis includes data from 2020 through December 16, 2025; data collection is ongoing, and additional analyses are planned upon study completion. The patient inclusion criteria include: ≥2 and ≤12 years of age at CPP diagnosis; has received at least 3 consecutive 6-month SC-LA injections; has been prescribed SC-LA for CPP use. Baseline was defined as the last recorded assessment prior to any GnRHa. Height velocity was calculated using the difference in height between visits and annualized for presentation. Pubertal maturation was categorized with a modified Tanner staging system using breast development for girls and external genitalia for boys.

A total of 40 children from 4 clinical sites were included, with 3-7 injections per child (up to 38 months of treatment) and a median follow-up of 26 months. Mean height velocity (HV) decreased from 7.5 cm/year at baseline to 6.9, 5.4, 5.1, and 5.4 cm/year during Months 1–6, 7–12, 13–18, and 19–24, respectively. Breast development Tanner stage in girls was maintained or regressed in 94, 96, 93, and 90% of evaluable patients during the same time periods, respectively. All 3 boys' external genitalia development remained at tanner stage 2 during the available follow-up time frame (12 months).

In this real-world, multi-site retrospective study, children were treated with 6-month 45 mg SC-LA for up to 38 months. SC-LA demonstrated sustained clinical suppression, including suppression of HV to the prepubertal range and stabilization of pubertal progression as reflected by maintained or regressed Tanner stage. These findings complement and extend the phase 3 pivotal trial results by providing supportive long-term real-world evidence for the effectiveness of SC-LA in children treated for CPP.

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