Due to transition of the Lupron program from TAP Pharmaceutical Products Inc. to Abbott, the primary purpose of the amendment is document changes regarding Sponsor name, contact information, fax number and a revised timeline for reporting SAEs. -include convulsions as a rarely reported event -document that the commercially-available generic leuprolide acetate daily injection (Leuprolide Acetate Injection) will be used to conduct the GnRHa Stimulation test. -reduce the allowable visit window from +/- 7 days to +/- 3 days at each of the Months 3, 6, 9 and 12 study visits. -clarify which procedures are required at the Early Discontinuation Visit and which procedures are optional if previously preformed or may be performed at the discretion of the investigator based on clinical judgment. -clarify that a copy of the hand-wrist radiograph will be maintained at the study site in the subject's study file and include reference to (and a sample of) the Hand/Wrist Radiograph Transmittal Form that is submitted with the radiograph to Lifespan -at the Months 3 and 9 study visits, the blood collections for basal gonadotropin and sex steroids are relative to the Depot Injection. No stimulation tests are performed at these visits. -indicate that any storage temperatures that fall outside the allowable range of temperature excursions, as defined by the product label and/or the Package Inserts, are to be communicated to Abbott. -incorporate a longer study duration as a result of the enrollment period of the lead-in study, L-CP07-167, having been extended a few months -update criteria for withdrawal (accelerated progression of pubertal symptoms), exclusion (bone age ≥ 14.00 years for girls and ≥ 15.00 years for boys is exclusionary) -clarify premature discontinuation from trial, permitted/prohibited medications, AE and SAE procedures

The purpose of this amendment is to extend the treatment period from 12 months to a total of 36 months to allow subjects to continue to be treated with study medication until a 3-month Depot formulation of leuprolide acetate is approved for the clinical treatment of central precocious puberty and is commercially available. The amendment also allows for subjects currently in the Safety Follow-up Period receiving Lupron Depot as standard of care to resume treatment with the 3-month Depot Investigational Product for an additional 24 months of treatment, following IRB approval. -add study visits to reflect the amendment. Study procedures and assessments such as stimulation tests, physical exams, pelvic ultrasound (girls), etc. to be performed during the study, as well as the change in names from Post-Treatment Follow-Up Period and Post-Treatment Follow-Up Visit to Safety Follow-Up Period and Safety Follow-Up Visit -indicate that the current immunochemiluminometric assay (ICMA) used for the analysis of LH will be changed to the electrochemiluminescent (ECL) methodology, once the ICMA assay is no longer supported by the central laboratory -indicate that following the Month 9 study visit, sites will no longer be required to call the parent the day following each injection to assess for any injection site reactions any hormonal flare response to the study drug. Instead, the parent will call the site to report any reactions or flare. The site will still be required to assess reaction/flare on the day of the injection prior to the subject leaving the clinic, and assess at the following study visit or by asking the parent/subject -provide instructions on storing the frozen samples for LH, estradiol and testosterone, if not shipped on the same day as the day of the blood draw. -clarify study procedures and add 2 interim analyses when all subjects finish their Month 12 and Month 24 visits