Timing of onset of menses after GnRH agonist treatment for central precocious puberty.

OBJECTIVES: To understand possible predictors of the onset of menses after gonadotropin-releasing hormone agonist treatment cessation in girls with central precocious puberty (CPP). METHODS: This exploratory post hoc analysis of a phase 3 and 4 trial of girls with CPP treated with once-monthly intramuscular leuprolide acetate examined onset of menses after treatment completion using a time-to-event analysis. Pretreatment and end-of-treatment chronologic age (CA), bone age (BA)/CA ratio, and Tanner breast stage; pretreatment menses status; and end-of-treatment BA and body mass index (BMI) were studied as potential factors influencing the onset of menses. RESULTS: Median time to first menses after stopping treatment was 18.3 months among 35 girls (mean age at onset of treatment, 6.8 years) examined. Of 26 girls experiencing menses, 11 (42 %) menstruated at 16-21 months after stopping treatment. Most girls with pretreatment BA/CA≥1.4 started menstruating very close to 18 months after stopping treatment; those with less advanced BA/CA experienced menses at 9-18 months. End-of-treatment BA/CA≥1.2 was associated with a quicker onset of menses (14.5 vs. 18.5 months for BA/CA<1.2, p=0.006). End-of-treatment BA≥12 years predicted longer time to menses. No relationship with time to menses was observed for pretreatment menarche status, pretreatment or end-of-treatment Tanner breast stage (<3/≥3) or CA (<6/≥6 or ≤11/>11), or end-of-treatment BMI percentiles (<85.6/≥85.6 and <92.6/≥92.6). CONCLUSIONS: Pretreatment menarche status or CA do not appear to predict onset of menses, but pre- and end-of-treatment BA/CA may be helpful in anticipating time to first menses after stopping treatment.

Using change in predicted adult height during GnRH agonist treatment for individualized treatment decisions in girls with central precocious puberty.

OBJECTIVES: It is important to understand what variables influence change in predicted adult height (PAH) throughout GnRHa treatment for central precocious puberty (CPP) to individualize treatment decisions and optimize care. METHODS: Changes in PAH, chronological age (CA), bone age (BA), BA/CA, and height velocity (HV) were evaluated in girls with CPP throughout treatment with leuprolide acetate (n=77). A second analysis focused on changes in the 3 years preceding the first observed BA of ≥12 years. Relationships were characterized using plot inspection and linear mixed-effects analyses. Association between treatment duration and last assessed PAH was examined using multiple linear regression models. RESULTS: BA/CA and HV showed a nonlinear change during treatment, with the largest changes and improvement in PAH observed in the first 6-18 months. Rate of BA advancement tended to decrease more slowly in girls initiating treatment at a younger BA. On-treatment change in PAH was predicted by concurrent BA/CA change, HV, and BA, as well as CA at treatment initiation. Last assessed PAH was positively associated with longer treatment durations (primary/exploratory models cut-offs of ≥33/≥55 months). CONCLUSIONS: These findings support individualized monitoring during GnRHa treatment. Initial response should be interpreted with caution until 6-18 months after treatment initiation and failure should not be assumed based on continued bone maturation in girls starting therapy at a younger age. Treatment cessation should not be automatically based on a diminishing change in PAH or HV, as ongoing treatment may result in continued increase or maintenance of PAH.

Efficacy and Safety of Leuprolide Acetate 6-Month Depot for the Treatment of Central Precocious Puberty: A Phase 3 Study.

Context: Treatment options for central precocious puberty (CPP) are important for individualization of therapy. Objective: We evaluated the efficacy and safety of 6-month 45-mg leuprolide acetate (LA) depot with intramuscular administration. Methods: LA depot was administered at weeks 0 and 24 to treatment-naïve (n = 27) or previously treated (n = 18) children with CPP in a phase 3, multicenter, single-arm, open-label study (NCT03695237). Week 24 peak-stimulated luteinizing hormone (LH) suppression (<4 mIU/mL) was the primary outcome. Secondary/other outcomes included basal sex hormone suppression (girls, estradiol <20 pg/mL; boys, testosterone <30 ng/dL), suppression of physical signs, height velocity, bone age, patient/parent-reported outcomes, and adverse events. Results: All patients (age, 7.8 ± 1.27 years) received both scheduled study doses. At 24 weeks, 39/45 patients (86.7%) had LH suppressed. Six were counted as unsuppressed; 2 because of missing data, 3 with LH of 4.35-5.30 mIU/mL and 1 with LH of 21.07 mIU/mL. Through 48 weeks, LH, estradiol, and testosterone suppression was achieved in ≥86.7%, ≥97.4%, and 100%, respectively (as early as week 4 for LH and estradiol and week 12 for testosterone). Physical signs were suppressed at week 48 (girls, 90.2%; boys, 75.0%). Mean height velocity ranged 5.0 to 5.3 cm/year post-baseline in previously treated patients and declined from 10.1 to 6.5 cm/year at week 20 in treatment-naïve patients. Mean bone age advanced slower than chronological age. Patient/parent-reported outcomes remained stable. No new safety signals were identified. No adverse event led to treatment discontinuation. Conclusion: Six-month intramuscular LA depot demonstrated 48-week efficacy with a safety profile consistent with other GnRH agonist formulations.

Importance of individualizing treatment decisions in girls with central precocious puberty when initiating treatment after age 7 years or continuing beyond a chronological age of 10 years or a bone age of 12 years.

OBJECTIVES: Gonadotropin-releasing hormone agonist treatment is important for optimal growth in girls with central precocious puberty (CPP). Data are lacking regarding benefit to height outcome when treatment is started after chronological age (CA) of 7 years, and if continued beyond CA of 10 years or bone age (BA) of 12 years. METHODS: Forty-eight girls with CPP were treated with monthly leuprolide depot. Change in predicted adult height (PAH) during treatment was assessed. Changes in PAH and growth velocity were compared between girls initiating treatment at CA <7 vs. ≥7 years, and BA ≥12 vs. BA <12 years. RESULTS: Mean baseline CA was 6.8 years, BA, 10.2 years; and PAH, 156.4 cm. BA/CA ratio decreased from pretreatment values, averaging 1.5 to 1.2 at the end of treatment. Proportion of girls with >5 cm PAH change during treatment was similar, and PAH increased throughout treatment in most girls, regardless of age at treatment initiation. PAH continued to increase in 16/19 girls who continued treatment after BA of 12 years, and also in 16/22 girls who continued treatment after CA of 10 years. CONCLUSIONS: PAH improved in most girls who initiated treatment after CA of 7 years. It continued to improve in most girls with longer treatment, even past BA of 12 years or CA of 10 years, which suggests that no absolute CA or BA limit should define initiation or end of treatment. Treatment plans need to be individualized, and neither treatment initiation nor cessation should be based on BA or CA alone.

Predictors of bone maturation, growth rate and adult height in children with central precocious puberty treated with depot leuprolide acetate.

BACKGROUND: Children with central precocious puberty (CPP) are treated with gonadotropin-releasing hormone agonists (GnRHa) to suppress puberty. Optimizing treatment outcomes continues to be studied. The relationships between growth, rate of bone maturation (bone age/chronological age [ΔBA/ΔCA]), luteinizing hormone (LH), predicted adult stature (PAS), as well as variables influencing these outcomes, were studied in children treated with depot leuprolide (LA Depot) Methods: Subjects (64 girls, seven boys) with CPP received LA Depot every 3 months for up to 42 months. Multivariate regression analyses were conducted to examine the predictors affecting ΔBA/ΔCA, PAS and growth rate. RESULTS: Ninety percent of subjects (18 of 20) were suppressed (LH levels <4 IU/L) at 42 months. Over 42 months, the mean growth rate declined 2 cm/year, the mean BA/CA ratio decreased 0.21 and PAS increased 8.90 cm for girls (n=64). PAS improved to mid-parental height (MPH) in 46.2% of children by 30 months of treatment. Regression analysis showed that only the Body Mass Index Standardized Score (BMI SDS) was significantly associated (ß+0.378 and +0.367, p≤0.05) with growth rate. For PAS, significant correlations were with MPH (ß+0.808 and +0.791, p<0.001) and ΔBA/ΔCA (ß+0.808 and +0.791, p<0.001). For ΔBA/ΔCA, a significant association was found only with BA at onset of treatment (ß-0.098 and -0.103, p≤0.05). Peak-stimulated or basal LH showed no significant influence on growth rate, ΔBA/ΔCA or PAS. CONCLUSIONS: Growth rate and bone maturation rate normalized on treatment with LA Depot. LH levels were not significantly correlated with growth rate, ΔBA/ΔCA or PAS, suggesting that suppression was adequate and variations in gonadotropin levels were below the threshold affecting outcomes.

Intramuscular depot formulations of leuprolide acetate suppress testosterone levels below a 20 ng/dL threshold: a retrospective analysis of two Phase III studies.

INTRODUCTION: Androgen deprivation therapy (ADT) with gonadotropin-releasing hormone (GnRH) analogs is a standard treatment for advanced prostate cancer. GnRH analog therapy can reduce testosterone to "castrate" levels, historically defined as <50 ng/dL. With the advent of newer assays, a lower threshold of <20 ng/dL has recently been proposed. We report the results of a retrospective analysis of two Phase III trials of 4- and 6-month depot microsphere formulations of leuprolide acetate (LA), a GnRH agonist that has previously demonstrated efficacy in testosterone suppression to <50 ng/dL in patients on ADT. This analysis investigates the ability of these LA formulations to suppress to ≤20 ng/dL levels. METHODS: In two of five AbbVie/Abbott clinical trials of microsphere formulations of LA for ADT, analytic technology permitting testosterone detection as low as 3 ng/dL was used and thus was selected for this analysis. Both trials were open-label, fixed-dose studies in prostate cancer patients, naïve to ADT. Patients received either 30 mg (4-month formulation; n=49) or 45 mg (6-month formulation; n=151) depot injections of LA microspheres. Treatment duration was up to 32 weeks for the 4-month formulation and 48 weeks for the 6-month formulation. The proportion of patients achieving the 20 ng/dL threshold was determined every 4 weeks. RESULTS: Pooled analysis showed that 152 of 193 (79%) of patients achieved serum testosterone levels of ≤20 ng/dL at 4 weeks, and sustained the improvement at week 24 (169/189, 89%). Additionally, in the 6-month study, 127/135 (94.1%) patients were suppressed to ≤20 ng/dL at 48 weeks. CONCLUSION: Both 4- and 6-month intramuscular depot formulations of LA achieved and maintained mean serum testosterone levels ≤20 ng/dL in the vast majority of patients as early as 4 weeks following treatment initiation. Additional research on the clinical relevance of this lower testosterone threshold is warranted.