A Study to Assess the Efficacy, Safety, and Pharmacokinetics of Debio 4326 in Pediatric Participants With Central Precocious Puberty (LIBELULA™ Clinical Trial)

Inclusion Criteria

• •1. Diagnosis of central precocious puberty.
• •2. Onset of development of sex characteristics (i.e., breast development in girls or testicular enlargement in boys according to the Tanner method) before the age of 8 years in girls and 9 years in boys.
• •3. Initially, only participants aged (a) 5 to 8 years inclusive (i.e., \<9 years) are eligible. The Sponsor will determine based on the recommendation of the DMC following the interim analysis whether participants aged (b) 2 to 4 years inclusive (i.e., \<5 years) and/or (c) 9 to 10 years inclusive (i.e., \<11 years) may be recruited.
• •4. Participant to receive at least 1 year of gonadotropin-releasing hormone agonist (GnRHa) therapy from study treatment start.
• •5. (a) Pre-treated participants: Start of initial GnRHa therapy no later than 18 months after onset of the first signs of CPP.
• •(b) Treatment-naive participants: Start of Debio 4326 treatment no later than 18 months after onset of the first signs of CPP.
• •6. (a) Pre-treated participants: Difference between bone age (Greulich and Pyle method) and chronological age of ≥1 year based on historical values at the initiation of the GnRHa therapy.
• •(b) Treatment-naive participants: Difference between bone age (Greulich and Pyle method) and chronological age of ≥1 year.
• •7. (a) Pre-treated participants: Pubertal-type LH response (LH ≥6 IU/L) following a GnRH/GnRHa stimulation test, or random non-stimulated serum LH \>0.5 IU/L (if considered local standard of care), based on historical values prior to the initiation of GnRHa therapy.
• •(b) Treatment-naive participants: Pubertal-type LH response (≥6 IU/L) 30 minutes following a GnRHa \[leuprolide acetate 20 micrograms per kilogram (μg/kg) subcutaneous injection (SC)\] stimulation test before treatment initiation.
• •8. (a) Pre-treated participants: Clinical evidence of puberty, defined as Tanner Staging ≥2 for breast development for girls and testicular volume ≥4 milliliter (mL) (cubic centimeter \[cc\]) for boys, prior to the initiation of GnRHa therapy.
• •(b) Treatment-naive participants: Clinical evidence of puberty, defined as Tanner Staging ≥2 for breast development for girls and testicular volume ≥4 mL (cc) for boys.