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• The efficacy of weekly somatrogon injections was no different from that of daily somatropin injections to treat children who don't make enough growth hormone to grow adequately. ○ Efficacy refers to how well a drug works in a clinical trial. ○ Children treated with weekly somatrogon had an increased growth rate, similar to that of children treated with daily somatropin . • The safety of weekly somatrogon injections was similar to that of daily somatropin injections. The original scientific article on which this summary is based was published in The Journal of Clinical Endocrinology & Metabolism and can be accessed for free at: https://academic.oup.com/jcem/article/107/7/e2717/6566444. The details of the original article are as follows: Cheri L. Deal, Joel Steelman, Elpis Vlachopapadopoulou, Renata Stawerska, Lawrence A Silverman, Moshe Phillip, Ho-Seong Kim, CheolWoo Ko, Oleg Malievskiy, Jose F. Cara, Carl L. Roland, Carrie Turich Taylor, Srinivas Rao Valluri, Michael P. Wajnrajch, Aleksandra Pastrak, and Bradley S. Miller. Efficacy and safety of weekly somatrogon vs daily somatropin in children with growth hormone deficiency: a phase 3 study. J Clin Endocrinol Metab 2022; 107(7): e2717-e2728. The purpose of this plain language summary is to help you to understand the findings from recent research. •  Somatrogon is used to treat growth hormone deficiency (the condition under study that is discussed in this summary). Approval varies by country; please check with your local healthcare provider for more details. • The results of this study may differ from those of other studies. Physicians/providers should make treatment decisions based on all available evidence and not on the results of a single study., (© The Author(s), 2024.)

Somatrogon-ghla is a long-acting, recombinant human growth hormone approved for the treatment of pediatric patients with growth hormone deficiency. Forty-nine healthy, adult males were enrolled in a randomized, crossover study to compare somatrogon exposure after subcutaneous doses administered using a frozen vial presentation or a prefilled, multiple dose pen. Somatrogon, insulin-like growth factor-I, and IGF-1 binding protein-3 concentrations were collected for up to 240 hours post dose to assess pharmacokinetic and pharmacodynamic responses. There was a 2-week washout between administration of the doses. Seven participants did not complete the study due to withdrawal of consent (n = 2) or loss to follow-up. Two treatment-emergent adverse events, headaches, were judged by the investigator as possibly related to study drug administration. Both were mild. Injection site reactions were observed in 6/48 participants after administration with the pen and 12/46 after administration using the vial. Drug and biomarker concentrations were assessed using validated assays and noncompartmental methods were used to determine pharmacokinetic and pharmacodynamic parameters. Bioequivalence was demonstrated for somatrogon area under the concentration-time curve, but not for the peak somatrogon concentration, where the lower limit of the 90% confidence interval for the ratio of pen/vial was 74.2%, which is less than the lower limit, 80.0%, dictated by bioequivalence criteria. The IGF-1 responses were largely within bioequivalence limits. It was concluded that the 2 formulations are comparable., (© 2024 Pfizer Inc and The Authors. Clinical Pharmacology in Drug Development published by Clinical Pharmacology in Drug Development on behalf of American College of Clinical Pharmacology.)

Objectives: Somatrogon is a long-acting recombinant human growth hormone used to treat patients with paediatric growth hormone deficiency (pGHD). This global phase 3 study compared the efficacy and safety of once-weekly somatrogon with once-daily somatropin in children with GHD., Methods: Prepubertal patients were randomized 1:1 to once-weekly somatrogon (0.66 mg/kg/week) or once-daily somatropin (0.24 mg/kg/week) for 12 months. The primary endpoint was height velocity (HV) at month 12; secondary endpoints included HV at month 6 and change in height standard deviation score (SDS) at months 6 and 12 and insulin-like growth factor 1 (IGF-1) SDS., Results: This post hoc subgroup analysis focused specifically on Asian children (somatrogon: n=24 and mean age=7.76 years; somatropin: n=21 and mean age=8.10 years) across eight countries. Mean HV at month 12 was 10.95 cm/year (somatrogon) and 9.58 cm/year (somatropin); the treatment difference of 1.38 cm/year favoured somatrogon. The lower bound of the two-sided 95 % CI of the treatment difference (somatrogon-somatropin) was -0.20, similar to the overall study population (-0.24). Compared with the somatropin group, the somatrogon group had numerically higher HV at month 6 (8.31 vs. 11.23 cm/year); a similar trend was observed for height SDS and IGF-1 SDS at months 6 and 12. Safety and tolerability were similar between treatment groups; adverse events occurred in 83 % of somatrogon-treated children and 76 % of somatropin-treated children., Conclusions: This subgroup analysis demonstrated that somatrogon efficacy and safety in Asian children were consistent with the overall study population, where once-weekly somatrogon was non-inferior to once-daily somatropin. Clinicaltrials.gov: NCT02968004., (© 2024 the author(s), published by De Gruyter, Berlin/Boston.)

The Kabi International Growth Study (KIGS) was first established in 1987 and is the largest pharmaco-epidemiological study of recombinant human growth hormone (rhGH). KIGS is aimed at evaluating long-term safety and treatment outcomes in pediatric subjects who received Genotropin rhGH therapy (Pfizer, New York, NY, USA) as prescribed by physicians in real-world clinical practice settings. KIGS data have been used to answer multiple research questions related to growth, growth prediction, and growth hormone treatment, leading to the publication of 129 peer-reviewed manuscripts and 24 biannual reports, outcomes from 10 expert meetings, and 3 books. The KIGS has shown that rhGH is safe and increases both the short-term height gain and adult height in patients with GH deficiency (GHD) and multiple other non-GHD conditions associated with short stature.

Context: The Kabi/Pfizer International Growth Database (KIGS) is a large, international database (1987-2012) of children treated with recombinant human growth hormone (rhGH) in real-world settings., Objective: This work aimed to evaluate the safety and efficacy of rhGH from the full KIGS cohort., Methods: Data were collected by investigators from children with growth disorders treated with rhGH (Genotropin [somatropin]; Pfizer). Safety was evaluated in all treated patients, and efficacy in those treated for 1 year or more. A subgroup included patients treated for 5 years or more (≥ 2 years prepubertal) who had reached near-adult height (NAH). Main outcomes included adverse events (AEs), serious AEs (SAEs), and height growth., Results: The full KIGS cohort (N = 83 803 [58% male]) was treated for idiopathic GH deficiency (IGHD; 46.9%), organic GHD (10.0%), small for gestational age (SGA; 9.5%), Turner syndrome (TS; 9.2%), idiopathic short stature (ISS; 8.2%), and others (16.2%). Median rhGH treatment duration was 2.7 years and observation 3.1 years. SAEs occurred in 3.7% of patients and death in 0.4%. The most common SAEs were recurrence of craniopharyngioma (n = 151), neoplasm (n = 99), and cancer (n = 91); and scoliosis (n = 91). Median first-year delta height-SD score (SDS) (Prader) in prepubertal patients was 0.66 (IGHD), 0.55 (ISS), 0.58 (TS), and 0.71 (SGA). Median gains in NAH-SDS were 1.79 (IGHD), 1.37 (ISS), and 1.34 (SGA) for boys, and 2.07 (IGHD), 1.62 (ISS), 1.07 (TS), and 1.57 (SGA) for girls., Conclusion: Data from KIGS, the largest and longest running international database of rhGH-treated children, show that rhGH is safe and increases short-term height gain and adult height across GHD and non-GHD conditions., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society.)

Background: Children with growth hormone deficiency (GHD) are treated with daily somatropin injections; however, poor treatment persistence and adherence have been recognized previously and have been shown to negatively impact growth outcomes. A recent real-world study of a US pediatric GHD population found that a substantial proportion of children discontinued somatropin therapy, but similar data for a real-world UK population are lacking., Objectives: To describe the discontinuation of, and persistence with, daily somatropin treatment among children with GHD in the UK., Methods: This was a retrospective cohort study of children (≥3 and <16 years old) with ≥1 medication prescription for daily injectable somatropin from 1 July 2000 to 31 December 2020 in the IQVIA Medical Research DATA (IMRD) database. Early persistence was defined as the proportion of children prescribed ≥1 somatropin refill (≥2 prescriptions). Discontinuation was defined as the first date at which a medication gap for somatropin (of >60 or >90 days between prescriptions) occurred. Kaplan-Meier methods were used to evaluate persistence (non-discontinuation) over time to assess time to first discontinuation event. Cox proportional hazards models were used to evaluate the relationship between patient characteristics and time to medication discontinuation., Results: Among the cohort identified in this study ( n  = 117), the majority ( n  = 84, 71.8%) had 48 months of available follow-up; 56.4% were boys and the mean (median) age was 8.6 (8.0) years. About 98% exhibited early persistence, but persistence over the follow-up period decreased with follow-up duration. Using the conservative 90-day gap definition of persistence, an estimated 72.4%, 52.8%, and 43.3% were persistent at 12, 36, and 48 months. Lower persistence rates were observed using the 60-day definition. No significant patient predictors of time to discontinuation were identified., Conclusions: Despite high early persistence with somatropin, a high percentage of children with GHD were increasingly non-persistent over time. More than 1 in 4 were non-persistent at 12 months and more than 1 in 2 were non-persistent at 48 months of follow-up. These results suggest that strategies to support improved medication-taking behavior among children with GHD in the UK are warranted., Competing Interests: JL, YC, JA, ES, JK, and MW are all employees of Pfizer Inc. and may hold stock/stock options. JW, DO, DB, and PJ are all employees of Genesis Research, LC, which was a paid consultant to Pfizer for this study. The authors declare that this study received funding from Pfizer Inc. The funder had the following involvement with the study: study design, data collection and analysis, decision to publish, and preparation of the manuscript., (Copyright © 2022 Loftus, Wogen, Oliveri, Benjumea, Jhingran, Chen, Alvir, Rivero-Sanz, Kowalik and Wajnrajch.)

Context: Data on long-term safety of growth hormone (GH) replacement in adults with GH deficiency (GHD) are needed., Objective: We aimed to evaluate the safety of GH in the full KIMS (Pfizer International Metabolic Database) cohort., Methods: The worldwide, observational KIMS study included adults and adolescents with confirmed GHD. Patients were treated with GH (Genotropin [somatropin]; Pfizer, NY) and followed through routine clinical practice. Adverse events (AEs) and clinical characteristics (eg, lipid profile, glucose) were collected., Results: A cohort of 15 809 GH-treated patients were analyzed (mean follow-up of 5.3 years). AEs were reported in 51.2% of patients (treatment-related in 18.8%). Crude AE rate was higher in patients who were older, had GHD due to pituitary/hypothalamic tumors, or adult-onset GHD. AE rate analysis adjusted for age, gender, etiology, and follow-up time showed no correlation with GH dose. A total of 606 deaths (3.8%) were reported (146 by neoplasms, 71 by cardiac/vascular disorders, 48 by cerebrovascular disorders). Overall, de novo cancer incidence was comparable to that in the general population (standard incidence ratio 0.92; 95% CI, 0.83-1.01). De novo cancer risk was significantly lower in patients with idiopathic/congenital GHD (0.64; 0.43-0.91), but similar in those with pituitary/hypothalamic tumors or other etiologies versus the general population. Neither adult-onset nor childhood-onset GHD was associated with increased de novo cancer risks. Neutral effects were observed in lipids/fasting blood glucose levels., Conclusion: These final KIMS cohort data support the safety of long-term GH replacement in adults with GHD as prescribed in routine clinical practice., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society.)

Context: Somatrogon is a long-acting recombinant human growth hormone (rhGH) in development for once-weekly treatment of children with growth hormone deficiency (GHD)., Objective: We aimed to compare the efficacy and safety of once-weekly somatrogon with once-daily somatropin in prepubertal children with GHD., Methods: In this 12-month, open-label, randomized, active-controlled, parallel-group, phase 3 study, participants were randomized 1:1 to receive once-weekly somatrogon (0.66 mg/kg/week) or once-daily somatropin (0.24 mg/kg/week) for 12 months. A total of 228 prepubertal children (boys aged 3-11 years, girls aged 3-10 years) with GHD, impaired height and height velocity (HV), and no prior rhGH treatment were randomized and 224 received ≥1 dose of study treatment (somatrogon: 109; somatropin: 115). The primary endpoint was annualized HV at month 12., Results: HV at month 12 was 10.10 cm/year for somatrogon-treated subjects and 9.78 cm/year for somatropin-treated subjects, with a treatment difference (somatrogon-somatropin) of 0.33 (95% CI: -0.24, 0.89). The lower bound of the 2-sided 95% CI was higher than the prespecified noninferiority margin (-1.8 cm/year), demonstrating noninferiority of once-weekly somatrogon vs daily somatropin. HV at month 6 and change in height standard deviation score at months 6 and 12 were similar between both treatment groups. Both treatments were well tolerated, with a similar percentage of subjects experiencing mild to moderate treatment-emergent adverse events in both groups (somatrogon: 78.9%, somatropin: 79.1%)., Conclusion: The efficacy of once-weekly somatrogon was noninferior to once-daily somatropin, with similar safety and tolerability profiles. (ClinicalTrials.gov no. NCT02968004)., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society.)

Purpose: To report the effects of pegvisomant (PEGV) treatment on patient-reported outcomes in acromegaly patients., Methods: We conducted an extension study of an open-label, multinational, non-interventional study (ACROSTUDY) evaluating the long-term safety and efficacy of PEGV for acromegaly in routine clinical practice. Enrolled patients were rollover patients from ACROSTUDY, or treatment naïve/semi-naïve (NSN; no PEGV within 6 months of enrollment). Exploratory efficacy endpoints were changes in symptoms with the Patient-Assessed Acromegaly Symptom Questionnaire (PASQ) and quality of life with the Acromegaly Quality of Life questionnaire (AcroQoL) analyzed by controlled or uncontrolled IGF-I levels. Results were analyzed in all patients, in NSN patient subgroup, and by diabetes status., Results: A total of 544 patients with acromegaly were enrolled, including 434 rollover subjects from ACROSTUDY and 110 NSN patients. Mean PEGV treatment duration was 7.8 years (range, 0-19.6 years). Overall, the majority of PASQ scores improved over time, but there was no significant difference between IGF-I controlled or uncontrolled groups. In the NSN subgroup, most PASQ and AcroQoL scores remained similar to baseline up to 1 year, regardless of IGF-I control. Patients with diabetes reported better PASQ scores over time with PEGV treatment, regardless of IGF-I control. IGF-I normalization increased from 10% of patients at baseline to more than 78% at year 10, with a mean daily PEGV dose of 18.7 mg., Conclusions: Overall, patients treated with PEGV had small improvements in PASQ. While IGF-I normalization increased with PEGV treatment, IGF-I control had no effects on PASQ and AcroQoL scores., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Objective: The objective of this retrospective cohort study was to describe the adherence and discontinuation patterns of somatropin over 3 years among children with pGHD insured by Medicaid across the United States., Methods: Eligible children were aged ≥3 and <16 years with Medicaid coverage, diagnosed with pGHD, and had ≥2 new prescriptions for somatropin between 1 July 2014 and 31 December 2018. Four non-exclusive patient cohorts were constructed (≥3, 12, 24, and 36 months of continuous enrollment after initial prescription). Suboptimal adherence was defined as medication possession ratio <0.80, and discontinuation as a gap of >60 days between somatropin fills. Logistic and proportional hazards regression methods were used to estimate odds of suboptimal adherence and time to discontinuation, respectively., Results: In the 12-month cohort ( n  = 3623), mean age was 10.5 ± 3.2 years, 70.8% were male, 44.4% White, 29.1% Hispanic, 7.1% Black, and 1.7% Asian. At months 12, 24, and 36, the proportion with suboptimal adherence was 40.9, 50.4, 54.4%, respectively, and 49.2% of patients with ≥3 months of follow-up discontinued therapy. At 12 months, lower age and race/ethnicity (Black vs. White referent) had greater odds of suboptimal adherence. Discontinuation was associated with Black (vs. White referent) race and geographic region., Conclusions: Sociodemographic characteristics may be risk factors for suboptimal adherence and/or discontinuation of prescribed somatropin therapy. Improving GH regimen adherence among this at-risk population, and specifically among subgroups at highest risk, is warranted to improve clinical outcomes.

Background: Limited real-world data from routine clinical care are available on the safety and effectiveness of treatment with taliglucerase alfa in patients with Gaucher disease (GD)., Methods: Taliglucerase Alfa Surveillance (TALIAS), a multinational prospective Drug Registry of patients with GD, was established to evaluate the long-term safety (primary objective) and effectiveness (secondary objective) of taliglucerase alfa. We present an interim analysis of the data from the Drug Registry collected over the 5-year period from September 2013 to January 2019., Results: A total of 106 patients with GD (15.1% children aged < 18 years; 53.8% females) treated with taliglucerase alfa have been enrolled in the Drug Registry, as of January 7, 2019. The median duration of follow-up was 795 days with quartiles (Q1, Q3) of 567 and 994 days. Fifty-three patients (50.0%) were from Israel, 28 (26.4%) were from the United States, and 25 (23.6%) were from Albania. At the time of enrollment, most patients (87.7%) had received prior enzyme replacement therapy (ERT). Thirty-nine of the 106 patients had treatment-emergent adverse events (AEs). Twelve of the 106 patients experienced serious AEs; two patients experienced four treatment-related serious AEs. Four patients died, although none of the deaths was considered to be related to taliglucerase alfa treatment by the treating physicians. Nine patients discontinued from the study, including the four who died. At baseline, patients with prior ERT had a higher mean hemoglobin concentration and platelet counts than treatment-naïve patients, likely reflecting the therapeutic effects of prior treatments. During follow-up, the hemoglobin concentration and platelet counts increased in the treatment-naïve patients and remained relatively constant or increased slightly in patients with prior ERT. Spleen and liver volumes decreased in treatment-naïve patients., Conclusions: The interim data showed no new or emergent safety signals. The overall interim data are consistent with the clinical program experience and known safety and effectiveness profile of taliglucerase alfa., (© 2022. The Author(s).)

Objective: To evaluate adherence to, and discontinuation of, somatropin treatment over 4 years in a US population-based study of children with pediatric growth hormone deficiency (pGHD)., Methods: A retrospective cohort analysis of commercially insured patients ≥3 and <16 years, diagnosed with pGHD, newly treated with somatropin was conducted using Optum De-identified Clinformatics Data Mart. Index date was defined as the first prescription for somatropin between 01 July 2002 and 30 September 2019. Five non-exclusive patient cohorts were identified (>3, 12, 24, 36, and 48 months of post-index continuous enrollment). Suboptimal adherence was defined as medication possession ratio <80%. Discontinuation was defined as the date at which a gap of >60 days between somatropin fills first occurred. Cox proportional hazards regression was used to evaluate time to discontinuation., Results: In the 12-month cohort ( n  = 3091), mean age was 11.3 ± 2.9 years, 75.9% were male, 70.9% white, 9.4% Hispanic, 3.6% Asian, and 3.1% black. The proportion with suboptimal adherence at months 12 and 48 was 19.6% and 35.9%, respectively. Discontinuation occurred in 42.2% of patients. The rate of discontinuation (HR [95% CI]) was higher for age ≥10 (1.74 [1.53-1.98]), females (1.35 [1.21-1.50]), black and Hispanic race/ethnicity (1.50 [1.18-1.90] and 1.27 [1.09-1.49] compared to White) and obesity (1.69 [1.19-2.40])., Conclusion: Suboptimal adherence increases with treatment duration, and risk of discontinuation is associated with age, female gender, black or Hispanic race/ethnicity, and obesity. Strategies that facilitate adherence among children at risk of discontinuation may improve clinical outcomes.

Objective: To report the final long-term safety and efficacy analyses of patients with acromegaly treated with pegvisomant from the ACROSTUDY., Design: Global (15 countries), multicentre, non-interventional study (2004-2017)., Methods: The complete ACROSTUDY cohort comprised patients with acromegaly, who were being treated with pegvisomant (PEGV) prior to the study or at enrolment. The main endpoints were long-term safety (comorbidities, adverse events (AEs), pituitary tumour volumes, liver tests) and efficacy (IGF1 changes)., Results: Patients (n = 2221) were treated with PEGV for a median of 9.3 years (range, 0-20.8 years) and followed up for a median of 7.4 years (range, 0-13.9 years). Before PEGV, 96.3% had received other acromegaly treatments (surgery/radiotherapy/medications). Before PEGV treatment, 87.2% of patients reported comorbidities. During ACROSTUDY, 5567 AEs were reported in 56.5% of patients and of these 613 were considered treatment-related (in 16.5% of patients) and led to drug withdrawal in 1.3%. Pituitary imaging showed a tumour size increase in 7.1% of patients; the majority (71.1%) reported no changes. Abnormal AST or ALT liver tests occurred in 3.2% of patients. IGF1 normalization rate improved over time, increasing from 11.4% at PEGV start to 53.7% at year 1, and reaching 75.4% at year 10 with the use of ≥30 mg PEGV/day in an increasing proportion of patients., Conclusion: This comprehensive review of the complete cohort in ACROSTUDY confirmed the overall favourable benefit-to-risk profile and high efficacy of PEGV as mono- and combination therapy in patients with an aggressive course/uncontrolled/active acromegaly requiring long-term medical therapy for control.

Context: Individual patients vary in their response to growth hormone (GH). No large-scale genome-wide studies have looked for genetic predictors of GH responsiveness., Objective: To identify genetic variants associated with GH responsiveness., Design: Genome-wide association study (GWAS)., Setting: Cohorts from multiple academic centers and a clinical trial., Patients: A total of 614 individuals from 5 short stature cohorts receiving GH: 297 with idiopathic short stature, 276 with isolated GH deficiency, and 65 born small for gestational age., Intervention: Association of more than 2 million variants was tested., Main Outcome Measures: Primary analysis: individual single nucleotide polymorphism (SNP) association with first-year change in height standard deviation scores. Secondary analyses: SNP associations in clinical subgroups adjusted for clinical variables; association of polygenic score calculated from 697 genome-wide significant height SNPs with GH responsiveness., Results: No common variant associations reached genome-wide significance in the primary analysis. The strongest suggestive signals were found near the B4GALT4 and TBCE genes. After meta-analysis including replication data, signals at several loci reached or retained genome-wide significance in secondary analyses, including variants near ST3GAL6. There was no significant association with variants previously reported to be associated with GH response nor with a polygenic predicted height score., Conclusions: We performed the largest GWAS of GH responsiveness to date. We identified 2 loci with a suggestive effect on GH responsiveness in our primary analysis and several genome-wide significant associations in secondary analyses that require further replication. Our results are consistent with a polygenic component to GH responsiveness, likely distinct from the genetic regulators of adult height., (© Endocrine Society 2020.)

Kearns-Sayre syndrome (KSS) is characterized by external ophthalmoplegia, retinal pigmentation and cardiac conduction defects due to mitochondrial DNA (mtDNA) deletions. Short stature and growth hormone (GH) deficiency have been reported in KSS, but data on GH treatment is limited. We describe the clinical presentation, phenotype evolution, and response to GH in a patient with KSS and report data on eight additional KSS patients from the KIGS database. Our patient with KSS and GH deficiency achieved a final adult height at -0.8 SDS. In the KIGS database GH treatment resulted in mean improvement in height from -3.9 to -2.9 SDS in patients with KSS. Two patients did not show growth improvement. Our data shows improvement in height SDS in our patient and mixed results in eight additional patients from the KIGS database after treatment with GH. Heterogeneity in responsiveness may relate to presence of GH deficiency or severity of underlying mitochondrial dysfunction.

Background/aims: Growth hormone (GH) treatment regimens for children with non-GH-deficient, idiopathic short stature (ISS) have not been optimized. To compare the efficacy, efficiency, and safety of an individualized, target-driven GH regimen with standard weight-based dosing after 4 years of treatment., Methods: This is a 4-year, open-label, multicenter, randomized trial comparing individualized, formula-based dosing of Genotropin® versus a widely used ISS dose of Genotropin®. Subjects were prepubertal, had a bone age of 3-10 years for males and 3-9 years for females, were naive to GH treatment, and had a height standard deviation score (Ht SDS) of -3 to -2.25, a height velocity <25th percentile for their bone age, and peak stimulated GH >10 ng/ml. After the first 2 years, the individualized-dosing group was further randomized to either 0.18 or 0.24 mg/kg/week., Results: At 4 years, subjects in all treatment regimens achieved similar average height gains of +1.3 SDS; however, the individualized dosing regimen utilized less GH to achieve an equivalent height gain., Conclusion: Individualized, formula-based GH dosing, followed by a dose reduction after 2 years, provides a more cost-effective growth improvement in patients with ISS than currently employed weight-based regimens., (© 2015 S. Karger AG, Basel.)

Background: Several models have been developed to predict growth response to growth hormone (GH) based on auxological and biochemical parameters for children with non-GH-deficient, idiopathic short stature (ISS)., Objective: To demonstrate if an individualized, formula-based, target-driven GH regimen for children with ISS would lead to a height (Ht) gain to -1.3 SDS during the first 24 months of treatment of this 4-year study, with less variability than with standard weight-based dosing., Methods: A 4-year, open-label, multi-center, randomized, two-arm study comparing formula-based dosing of Genotropin® GH from 0.18 to 0.7 mg/kg/week versus standard FDA-approved ISS dosing of Genotropin® (0.37 mg/kg/week). Subjects (n = 316, 89 females) were prepubertal, 3-14 years of age, bone age 3-10 years (m) and 3-9 years (f), naive to GH treatment, Ht SDS -3 to -2.25, Ht velocity <25th percentile for bone age, and peak GH >10 ng/ml., Results: The majority (83%) of subjects had Ht SDS within the normal range by 2 years. All subjects displayed catch-up growth consistent with other studies of GH treatment of ISS., Conclusion: The formula-based therapy did not meet the primary endpoint achieving targeted gain with lower variability. No new safety concerns were found., (Copyright © 2013 S. Karger AG, Basel.)

Growth hormone deficiency (GHD) and central precocious puberty (CPP) have each, individually, been described in patients with Klinefelter syndrome. However, the combination of GHD, CPP, and Klinefelter syndrome has never been reported. We described a Klinefelter syndrome patient who developed GHD at age 2 10/12 years and CPP at 8 6/12 years. Despite CPP, GnRH agonist therapy was not initiated because of his excellent predicted adult height. At 11 8/12 years, his height was 164.6 cm, close to his mid-parental target height of 165 cm. We report an additional nine patients with Klinefelter syndrome and GHD from the Pfizer International Growth Study (KIGS) database, none of whom had CPP. We conclude that the combination of GHD and CPP is very rare in Klinefelter syndrome and that CPP is unlikely to compromise final adult height.

Objective: Childhood-onset GH deficiency (COGHD) is associated with low bone mineral density (BMD). Adults with persistent COGHD may be at risk for insufficient bone accrual or bone loss during adulthood. The purpose of this study was to identify BMD predictors and to characterize the effects of GH replacement on BMD in COGHD adults with persistent GHD., Design: Retrospective analysis of the KIMS database., Methods: Variables predicting standardized BMD (sBMD) were identified. The effect of GH replacement (3 years) on BMD was examined., Results: Three hundred and fourteen COGHD adults (148 women, 166 men; 62 non-naïve, 178 semi-naïve, and 74 true naïve, depending on length and timing of previous GH replacement), who had BMD measured in lumbar spine (LS) and femoral neck (FN) at study entry. In semi-naïve subjects, a longer gap in GH replacement between childhood and adulthood was predictive of lower sBMD in the FN (r=-0.18, P=0.038). TSH deficiency predicted lower sBMD in the LS (r=-0.16, P=0.052). In true naïve patients, a longer gap between onset of pituitary disease and study entry (r=-0.35, P=0.012), and female gender (r=-0.27, P=0.043) independently predicted lower sBMD in the FN. There were no differences in BMD increases between non-naïve, semi-naïve, and true naïve subjects on GH replacement., Conclusions: In semi-naïve subjects a longer interval off GH replacement was associated with lower sBMD in the FN. Among true naïve patients, a longer gap between the onset of pituitary disease and GH replacement, and female gender predicted lower sBMD in the FN.

Background: Exemestane is an irreversible steroidal inhibitor of cytochrome-P450 aromatase required for estrogen synthesis. The safety of the drug in the pediatric population, particularly in males, has not previously been evaluated. Given the increased interest in treating children with aromatase inhibitors, we undertook a study in rats to assess the potential for exemestane to alter reproductive development and function when administered to juveniles., Methods: Male and female rats were treated with exemestane at doses anticipated to produce exposures approximately 2- and 35-fold the expected clinical plasma exposure in young adult males during the period of reproductive maturation. After maturation, treated rats were mated to evaluate the potential impact on reproductive function., Results and Conclusion: There were no effects on sexual maturation in either sex or on female reproductive function. Treatment of juvenile male rats caused increased cohabitation time and decreased copulation rates; pregnancy rates and litter size were not affected in rats that mated. Decreased testis (10-15%) and epididymis (20-30%) weights, and decreased Sertoli cell numbers were noted at all doses. This indicates that exemestane can reduce Sertoli cell proliferation during maturation. The sensitive window for this effect is expected to be limited to the period of Sertoli cell proliferation, which is completed by around postnatal day 15 in rats and before puberty in humans. Treatment beginning at a later time relative to the window for Sertoli cell proliferation or for a longer duration is not expected to have additional adverse effect as the effect was not shown to be degenerative., (© 2011 Wiley-Liss, Inc.)

Context: GH deficiency (GHD) is associated with low bone mineral density (BMD). Risk factors for lower BMD in this GHD population have not been fully elucidated. In particular, there are limited published data in GH-naïve subjects., Objective: The objective of the study was to identify endocrine correlates of low BMD in treatment-naïve adult GHD subjects., Design: This was a retrospective analysis of data extracted from the (Pfizer International Metabolic Study) KIMS database., Setting: The study was an international epidemiological survey of more than 15,000 adult GHD patients from 31 countries., Patients: A total of 1218 subjects with stringently defined GHD of adult onset (641 women and 577 men) who were GH naïve and had BMD measured in the posterior anterior lumbar spine and femoral neck by dual-energy X-ray absorptiometry., Main Outcome Measures: Variables associated with standardized BMD (sBMD) in adult-onset GHD were examined., Results: In the LS, body mass index (r = 0.13, P < 0.01), unreplaced sex steroid deficiency (r = -0.17, P < 0.0001), and corticotropin deficiency (r = -0.11, P < 0.01) were independently associated with sBMD. In the FN, age (r = -0.19, P < 0.0001), female gender (r = -0.18, P < 0.0001), body mass index (r = 0.21, P < 0.0001), and decreased IGF-I SD scores (r = 0.10, P < 0.001) were independently associated with sBMD., Conclusions: Hormone variables associated with lower sBMD in patients with adult-onset GHD include unreplaced sex steroid deficiency and corticotropin deficiency in the LS and lower IGF-I SDS in the FN.

Background: Improved ease of use of drug-delivery devices may enhance compliance. Development of an easier-to-use device for administration of recombinant human growth hormone (rhGH) may thus be beneficial for patients and their caregivers., Objective: This study compared ease of use and preference for a new disposable rhGH injection pen relative to previous experience with the currently available reusable pen in standard practice. Both pens deliver the same formulation of rhGH., Methods: This multicenter, single-arm, open-label study assessed ease of use and preference for the 2 injection pens in patient-caregiver dyads. Eligible children were aged 8 through 18 years, were currently being treated with rhGH, and had been compliant with use of the current reusable pen for ≥ 3 months before study entry. A validated self-reported Injection Pen Assessment Questionnaire was administered twice during the study-at baseline (to assess perceptions of the reusable pen) and after 2 months of use of the new disposable pen-to assess ease of use of the individual pens (rated on a 5-point Likert-type scale), the comparative ease of use of the 2 pens, and pen preference. The primary end point was the proportion of dyads who rated the new pen as no different or easier to use than the current pen. Regardless of treatment or suspected causal relationship to the investigational product, all observed or volunteered adverse events (AEs) were recorded and rated as mild, moderate, or severe., Results: Of 137 screened dyads, 136 (91 boys, 45 girls) were included in the safety population and 133 were included in the efficacy population. The children had a mean age of 12.3 years, a mean weight of 42.2 kg, a mean height of 145.9 cm, and a mean body mass index of 19.3 kg/m(2); 84.6% of the children were white. The majority (82.4%) of adult dyad members were subjects' mothers. The adult dyad members were more likely than the child members to be responsible for preparing the injection (82.0%) and administering the injection (72.9%). Overall, 73.7% of dyads rated the new disposable pen no different or easier to use than the reusable pen (95% CI, 66.2%-81.2%), and 65.2% rated the disposable pen no different or preferable to the reusable pen (95% CI, 57.0%-73.3%). Overall, 60 all-causality AEs occurred in 28 subjects (20.6%), most of them (93.3%) either mild or moderate in intensity. Eight device-related AEs occurred in 7 subjects (5.1%) (injection-site hematoma in 3 and injection-site pain in 5). The most common AEs were headache (7 events), injection-site pain (5), upper respiratory tract infection (4), and pyrexia (4). No deaths or serious AEs were reported., Conclusions: Nearly three quarters of patients and caregivers reported that the new disposable pen was no different or easier to use than the reusable pen, and nearly two thirds preferred the disposable pen. No safety concerns were identified. The findings suggest that the improvements in the new pen were recognized by patients and caregivers., (©2010 Elsevier HS Journals, Inc.)

Patients with rare and complex diseases such as congenital adrenal hyperplasia (CAH) often receive fragmented and inadequate care unless efforts are coordinated among providers. Translating the concepts of the medical home and comprehensive health care for individuals with CAH offers many benefits for the affected individuals and their families. This manuscript represents the recommendations of a 1.5 day meeting held in September 2009 to discuss the ideal goals for comprehensive care centers for newborns, infants, children, adolescents, and adults with CAH. Participants included pediatric endocrinologists, internal medicine and reproductive endocrinologists, pediatric urologists, pediatric surgeons, psychologists, and pediatric endocrine nurse educators. One unique aspect of this meeting was the active participation of individuals personally affected by CAH as patients or parents of patients. Representatives of Health Research and Services Administration (HRSA), New York-Mid-Atlantic Consortium for Genetics and Newborn Screening Services (NYMAC), and National Newborn Screening and Genetics Resource Center (NNSGRC) also participated. Thus, this document should serve as a "roadmap" for the development phases of comprehensive care centers (CCC) for individuals and families affected by CAH.

Background: Gender disparities were found in reports of early pediatric recombinant human GH (rhGH) use in the United States. With rhGH entering its third decade, we sought to examine U.S. gender-based treatment patterns and how these patterns compare with that of other countries., Methods: All children entered in the Pfizer International Growth Study, a database designed to document long-term outcomes and safety of Genotropin (Pfizer, New York, NY), were categorized by gender, location, date and age of therapy initiation, and diagnosis. Measures of national health status, health care expenditure, general economic indices, and mean adult heights were also compared., Results: Throughout the past 20 yr, the United States had an almost 2:1 male to female ratio overall. The gender ratio depended on the specific indication and age. There was no consistent relation to geographical region, pediatric population size, or density of pediatric endocrinologists. Male predominance was seen in Asia (mostly Japan), the United States, and Europe/Australia/New Zealand (65, 64, and 55%, respectively), but not the rest of the world (47%), where rhGH was prescribed less frequently. In the countries with the greatest rhGH use, the gender ratios depended on the specific indications but did not correlate with mean adult height, national health care measures, or general economic indices., Conclusions: Male predominance among U.S. pediatric rhGH recipients persists, especially for indications without a clear organic etiology. Global differences in gender ratios suggest that factors other than biology are at play. We speculate that social and cultural pressures and the health care systems' permissiveness toward paying for rhGH therapy contribute to these international differences.

Background: Previous studies of varied populations of non-uniformly defined children born small for gestational age (SGA) receiving different growth hormone (GH) regimens have found that GH treatment increased growth velocity and adult height and was safe. The GH dose was the major predictor of first year growth response., Aim: To identify pre- and within-treatment predictors of growth in well defined children born SGA treated with a fixed dose of GH., Methods: 139 short, prepubertal children born SGA (i.e. birth weight and/or length > or =2 standard deviations below the mean) received Genotropin (rhGH) at 0.24 mg/kg/wk for 1 month then an additional 11 months at a dose of 0.48 mg/kg/wk, the FDA-approved dose of GH for children born SGA., Results: Height improved significantly by month 3, with progressive improvement over the entire 12 months (median height SDS change of 0.78). Pretreatment predictors of growth included baseline bone age, IGFBP-3, total cholesterol, WBC and height SDS minus mid-parental height SDS. Within-treatment predictors of the change (Delta) height SDS at month 12 were the A height SDS at months 3 and 6 and growth velocity SDS at months 3 and 6., Conclusion: GH at 0.48 mg/kg/wk was well tolerated and improved growth in children born SGA; the Delta IGF-I was not predictive of the 12 month height SDS gain, while the Delta height SDS at 3 and 6 months were predictive. Underweight children grew as well as normal weight children, and both groups showed improved body composition following GH treatment.

Context: G to A transition at position 6,664 (G6664A) in human GH-1 results in the substitution of arginine by histidine at position 183 (R183H) of the GH molecule and causes familial isolated GH deficiency type II (IGHD II)., Objectives: The objective of the study was to assess the phenotype-genotype correlation of subjects affected with IGHD II caused by a G6664A mutation in 34 affected members of two large families., Design and Patients: Sixty-six subjects from two core families were included. The G6664A mutation among family members was determined by restriction fragment length polymorphism., Results: Twenty-four of the 52 members from family 1 and 10 of 14 from family 2 carried the same G6664A mutation in a heterozygous state. The affected subjects in family 1 were significantly shorter [-2.6 vs. -0.1 sd score (SDS), P < 0.0001] and had significantly lower IGF-I serum levels (-1.9 vs. -0.5 SDS, P < 0.0001), compared with normal-genotype family members. The affected adults exhibited great variability in their stature, ranging from -4.5 to -1.0 (mean -2.8 SDS), with five members being of normal height (>-2 SDS). Twelve children were diagnosed with IGHD. Two affected children had normal peak GH levels, although one of these subsequently demonstrated GH insufficiency (6.5 and 3.7 ng/ml). The affected children from both families exhibited large variability in their height, growth velocity, delay in bone age (chronological age - bone age), age at diagnosis, peak GH response, and IGF-I levels., Conclusions: These detailed phenotypic analyses show the variable expressivity of patients bearing a G6664A mutation, reflecting the spectrum of GH deficiency in affected patients, even within families, and the presence of additional genes modifying height determination. Our findings raise a new dilemma in the guidelines for the diagnosis of GH deficiency and the indications for GH therapy.

Objective: Our objective was to describe the first case of the successful use of pegvisomant during pregnancy in a woman with acromegaly., Design: We present the case of a 26-yr-old female with acromegaly who had failed surgical and subsequent medical therapy but whose disease was well controlled on pegvisomant. She then conceived and was continued on pegvisomant throughout pregnancy. We then collected both maternal and cord blood samples at parturition, and later analyzed her breast milk., Results: Maternal IGF-I was well controlled during gestation. Fetal GH and IGF-I were within the normal range. Maternal pegvisomant levels were consistent with a 25-mg daily dosage. Fetal pegvisomant levels were minimal and near the range detected in untreated acromegalic patients, likely representing minimal cross-reactivity from endogenous GH or spurious contamination by maternal blood. GH variant levels in the maternal blood and the cord blood were both within the normal ranges. Pegvisomant levels in breast milk were below the lower limit of quantification of the assay and similar to those observed when analyzing breast milk samples from normal mothers in the same assay. Fetal growth parameters were normal; the baby was healthy and showed no adverse signs., Conclusions: Pegvisomant therapy during gestation was safe and effective in our patient. Transplacental passage of pegvisomant is either absent or minimal, with a concentration highly unlikely to convey any significant pharmacodynamic effects on the fetal GH and IGF-I system. In addition, there is no evidence of substantial secretion of pegvisomant into breast milk.

Background: Recently, growth hormone (GH) therapy for children with short stature born small for gestational age (SGA) has been approved in the USA and Europe. There have been few reports examining adverse events during GH treatment of these children., Aims: (i) To examine glucose tolerance and insulin sensitivity during GH treatment of children born SGA in a US trial. (ii) To determine and compare adverse events reported in children born SGA with those reported in children with idiopathic short stature (ISS) enrolled in KIGS - Pfizer International Growth Database., Methods: In the US SGA trial, an oral glucose tolerance test was performed and fasting plasma glucose, insulin and glycosylated haemoglobin (HbA(1C)) concentrations were measured at baseline and after 12 months of GH therapy. Insulin sensitivity was calculated using the homeostasis model assessment (HOMA) and the quantitative insulin sensitivity check index (QUICKI). In the KIGS analysis, a retrospective audit of spontaneously logged cumulative adverse events in children born SGA and those with ISS was undertaken. Adverse events are reported per 1,000 patients. Values are expressed as mean with 10th-90th percentiles., Results: In the US trial, 84 patients had complete data sets for analysis. Median birth weight was 1.78 kg (SDS, -2.5) and birth length 43 cm (SDS, -2.2) at a median gestational age of 36.5 weeks; 79% were Caucasian. At entry, median age of the patients analysed was 6.6 years, and 65% were male. Median height was 104.3 cm (SDS, -2.97), median weight 15.95 kg (SDS, -2.21) and body mass index 14.66 kg/m(2) (SDS, -0.67). No patients developed impaired glucose tolerance or overt diabetes mellitus. The 0-min glucose concentration was 81 mg/dl at baseline and 86 mg/dl at 1 year, while the 120-min glucose concentration was 90 mg/dl at baseline and 96 mg/dl at 1 year. The 0-min insulin concentrations were 2.9 mU/l at baseline and 5.3 mU/l at 1 year, while the 120-min insulin levels were 7.7 mU/l at baseline and 11 mU/l at 1 year. The proportions of HbA(1C) were 5.2 and 5.4% at baseline and 1 year, respectively. HOMA and QUICKI values were 0.59 and 0.42, respectively, at baseline, and 1.13 and 0.38 at 1 year. In KIGS, there were 1909 children born SGA aged 9.1 (3.9-13.3) years with a birth weight SDS of -2.6 (-4.0 to -1.5), birth length SDS of -2.7 (-4.3 to -1.3) and height SDS of -2.71 (-3.9 to -1.8) prior to treatment. GH doses ranged from 0.032 to 0.037 in the USA and from 0.022 to 0.023 mg/kg/day in the remaining countries in KIGS. Neither total (187 vs. 183) nor serious (14 vs. 10) adverse events occurred more commonly in the SGA group than in the ISS group. Although respiratory adverse events occurred more commonly in children born SGA (34.3 vs. 16.8; p < 0.05), endocrine (12.0 vs. 2.7; p < 0.05) and hepatobiliary (6.2 vs. 1.1; p < 0.05) adverse events occurred more commonly in children with ISS., Conclusions: As expected, a reduction in insulin sensitivity occurred during GH treatment of children born SGA; however, glucose tolerance remained normal. No adverse events were reported more commonly in children born SGA than in those with ISS. Minor differences in adverse events reporting within organ systems between children born SGA and those with ISS are probably due to variable under-reporting of adverse events. GH appears to be a safe drug to use at current doses as a growth-promoting agent in short children born SGA., (Copyright 2006 S. Karger AG, Basel.)

Context: Treatment of GH-deficient adolescents in transition to adulthood remains challenging., Objective: The objective was to assess the safety and efficacy of GH in GH-deficient adolescents in transition., Patients: Fifty-eight GH-deficient adolescents (mean age, 15.8 +/- 1.8 yr; 33 males) at near completion of their linear growth participated in the study., Intervention: Baseline studies were done while subjects were on GH. Subjects were retested (insulin-induced hypoglycemia) 4 wk after GH discontinuation and reclassified as persistently GH-deficient or controls (n = 18). GH-deficient subjects were randomized to GH (n = 25, approximately 20 microg/kg.d) or placebo (n = 15)., Setting: The multicenter study was conducted over a 2-yr period., Main Outcomes: Changes in body composition, bone mineral density (BMD), quality of life (QOL), cardiovascular and metabolic markers were measured., Results: All groups had normal measures of lipid and carbohydrate metabolism, body composition, BMD, cardiac function, muscle strength, and QOL at baseline and after 2 yr. IGF-I concentrations decreased in all, but less so in the GH-group (P = 0.013). There was a greater increase in lean body mass (lesser adiposity) in the GH group than placebo at 12 months, but not at 24 months., Conclusions: 1) GH-deficient patients properly treated in childhood can have normal BMD, body composition, cardiac function, muscle strength, carbohydrate and lipid metabolism, and QOL when reaching adult height; and 2) continuation of GH therapy for 2 yr did not change these measures as compared to placebo-treated or control subjects. GH-deficient adolescents in good metabolic status at the time of epiphyseal fusion may safely discontinue GH for at least 2 yr. Follow-up is needed to determine whether GH therapy is eventually warranted in subjects treated with GH during childhood.

Growth hormone (GH) secretion is normally episodic, with discrete bursts of GH super-imposed on a minimal basal level of production. This pattern of GH production yields a dynamic state between a low baseline and intervening peaks, posing a challenge for the clinician attempting to understand the 'true GH status' in a specific patient. This pulsatile pattern is maintained throughout the day, but there are clear differences between different segments of the day, with approximately two-thirds of the total daily secretion produced at night. The dynamic nature of GH production has led many investigators to suggest that when evaluating short stature, parameters of spontaneous GH production be applied rather than the GH response to artificial stimulation. GH secretory patterns in healthy control populations are compared to those in patients with several conditions seen by the pediatric endocrinologist (classical GH deficiency, GH neurosecretory dysfunction, acute lymphoblastic leukemia, hypothyroidism, small for gestational age, Russell-Silver syndrome, constitutional delay of growth and puberty and Fanconi's anemia) and variables used for analysis of these patterns are described. Inferences made from comprehensive evaluations of the GH axis in Fanconi's anemia provide unique insight into general GH pathophysiology.

We are reporting a child with congenital panhypopituitarism, in whom deficient fetal steroidogenesis was suspected prenatally because of undetectable estriol levels measured in the maternal triple-marker screen. No fetal abnormalities were detected by ultrasonography. Amniocentesis demonstrated a normal 46,XX karyotype. Measurement of maternal urinary steroids failed to show elevation in the excretion of the major precursor for estriol, 16 alpha-hydroxydehydroepiandrosterone, indicating that the fetus did not have steroid sulfatase deficiency (placental sulfatase deficiency), the most common genetic cause of extremely low estriol. The steroid analysis excluded other rare single gene defects, including aromatase deficiency and 17 alpha-hydroxylase deficiency. We therefore suspected that the cause of low estriol in this fetus was adrenal insufficiency. Postnatal evaluation was consistent with panhypopituitarism, characterized by deficiency of all anterior pituitary hormones. Because this screen is now offered to more than half the pregnant women in the United States, reports of low estriol levels have become increasingly common. Therefore, it is essential that physicians be familiar with the various etiologies, perform the appropriate antenatal evaluation to determine the specific cause, and closely monitor both mother and child ante- and postnatally.

The growth hormone releasing hormone receptor (GHRHR) plays a critical role in growth. We identified three nominally unrelated kindreds harboring the identical mutation (E72X) in GHRHR, the gene that encodes GHRHR; all three families originated in the Indian subcontinent. Because of the relative geographic proximity of these populations, we employed haplotype analysis in the region of GHRHR to determine the likelihood that this mutation occurred in a common ancestor rather than having occurred on separate occasions in different individuals. Members of all three kindreds segregating the E72X mutation were genotyped for highly polymorphic dinucleotide repeat microsatellites in a 15.5 centimorgan (cM) region around GHRHR on chromosome 7p15. We conclude that the affected individuals share a common ancestor, and we use the association with linked markers to estimate the age of this unique mutation., (Copyright 2003 Wiley-Liss, Inc.)

Growth in humans is a complex process, controlled at numerous levels and by a myriad of factors. These factors may act centrally or peripherally and may be hormones, receptors, or transcription factors. Many of these probably are still unknown. The factors that are discussed here include those that act on the developing pituitary gland (transcription factors including LHX3, HESX1, PROP1, and PIT-1); those that regulate the normal activity of the pituitary (hypothalamic hormones such as GHRH, Ghrelin [growth hormone secretagoguel and somatostatin); those factors coming from the pituitary (essentially growth hormone [GH]); and the downstream modulators, transducers, and effectors of GH (including the GH receptor/GH binding protein, insulin-like growth factor-I and -II, their receptors, and their binding factors). What is becoming increasingly clear is the role of genetics in determining stature. This review discusses the most clinically relevant factors, with an emphasis on ontogeny, genetic inheritance, and clinical presentation.

Objectives: 1) To determine the extent of short stature in patients with Fanconi anemia (FA); 2) to determine the extent and nature of endocrinopathy in FA; 3) to assess the impact on height of any endocrinopathies in these patients; and 4) to study the correlation, if any, between height, endocrinopathy, and FA complementation group., Study Design: Fifty-four patients with FA, 30 males and 24 females from 47 unrelated families, were prospectively evaluated in a Pediatric Clinical Research Center. The patients ranged in age from 0.1-31.9 years, with the mean age at assessment 8.6 years., Results: Endocrine abnormalities were found in 44 of the 54 FA patients tested (81%), including short stature, growth hormone (GH) insufficiency, hypothyroidism, glucose intolerance, hyperinsulinism, and/or overt diabetes mellitus. Twenty-one of 48 (44%) participants had a subnormal response to GH stimulation; 19 of 53 (36%) had overt or compensated hypothyroidism, while 8 of 40 participants had reduced thyroid-hormone binding. Two patients were diabetic at the time of study; impaired glucose tolerance was found in 8 of 40 patients (25%), but most surprisingly, hyperinsulinemia was present in 28 of 39 (72%) participants tested. Significantly, spontaneous overnight GH secretion was abnormal in all patients tested (n = 13). In addition, participants demonstrated a tendency toward primary hypothyroidism with serum tetraiodothyronine levels at the lower range of normal, while also having thyrotropin (thyroid-stimulating hormone) levels at the high end of normal. Sixteen patients were assigned to FA complementation group A, (FA-A), 12 to FA-C, and 5 to FA-G; 10 of the 12 participants in FA-C were homozygous for a mutation in the intron-4 donor splice site of the FANCC gene. Patients in groups FA-A and FA-G were relatively taller than the group as a whole (but still below the mean for the general population), whereas those in FA-C had a significantly reduced height for age. GH response to stimulation testing was most consistently normal in participants from FA-G, but this did not reach statistical significance. The tendency toward hypothyroidism was more pronounced in participants belonging to complementation groups FA-C and FA-G, whereas insulin resistance was most evident in patients in FA-G, and least evident in those in FA-C. Short stature was a very common finding among the patients with a mean height >2 standard deviations below the reference mean (standard deviation score: -2.35 +/- 0.28). Patients with subnormal GH response and those with overt or compensated hypothyroidism were shorter than the group with no endocrinopathies. The heights of those participants with glucose or insulin abnormalities were less severely affected than those of normoglycemic, normoinsulinemic participants, although all were significantly below the normal mean. The mean height standard deviation score of patients with entirely normal endocrine function was also >2 standard deviations below the normal mean, demonstrating that short stature is an inherent feature of FA., Conclusion: Endocrinopathies are a common feature of FA, primarily manifesting as glucose/insulin abnormalities, GH insufficiency, and hypothyroidism. Although short stature is a well-recognized feature of FA, 23 patients (43%) were within 2 standard deviations, and 5 of these (9% of the total) were actually above the mean for height for the general population. Those patients with endocrine dysfunction are more likely to have short stature. These data indicate that short stature is an integral feature of FA, but that superimposed endocrinopathies further impact on growth. The demonstration of abnormal endogenous GH secretion may demonstrate an underlying hypothalamic-pituitary dysfunction that results in poor growth.

Familial isolated GH deficiency type II is an autosomal dominant form of short stature, associated in some families with mutations that result in missplicing to produce del32-71-GH, a protein that cannot fold normally. The mechanism by which this mutant suppresses the secretion of wild-type GH encoded by the normal allele is not known. Coexpression of del32-71-GH with wild-type human GH in transient transfections of the neuroendocrine cell lines GH4C1 and AtT20 suppressed accumulation of wild-type GH. The suppression of wild-type GH accumulation by del32-71-GH was a posttranslational effect on wild-type GH caused by decreased stability, rather than decreased synthesis, of wild-type GH. Coexpression of del32-71-GH with human PRL did not suppress accumulation of PRL, indicating that there was not a general suppression of secretory pathway function. Accumulation of del32-71-GH protein was not necessary for the suppression of wild-type GH, because del32-71-GH did not accumulate in the neuroendocrine cell lines in which suppression of accumulation of wild-type GH was observed. Del32-71-GH did accumulate in transfected COS and CHO cells, but did not suppress the accumulation of wild-type GH in these cells. These studies suggest that del32-71-GH may cause GH deficiency in somatotropes of heterozygotes expressing both wild-type and del32-71-GH by decreasing the intracellular stability of wild-type GH.

Basic and translational research achievements over the past 2 decades have disclosed the molecular mechanisms underlying several genetic forms of hypopituitarism. Disorders that are limited to the hypothalamic, pituitary, GH axis are caused by mutations in individual components of that axis. Disorders involving GH and one or more additional pituitary hormones are caused by mutations in the homeodomain transcription factors that direct embryological development of the anterior pituitary gland. Pit-1 has a POU-specific and a POU-homeo DNA-binding domain. The phenotype produced by mutations in the PIT1 gene involves deficiencies of GH, PRL, and TSH. Pituitary glands are either small or normally sized. The PROP1 gene encodes a transcription factor with a single paired-like DNA-binding domain. Persons with inactivating mutations in PROP1 have deficiencies of LH and FSH, as well as GH, PRL, and TSH. Their pituitary glands may be small, normally sized, or extremely large and show suprasellar extension. Pituitary degeneration may produce acquired deficiency of ACTH. Expression of the HESX1 gene precedes expression of PROP1 and PIT1, and it is much more widespread. The protein has a paired-like domain, and it competes with the product of PROP1 for DNA-binding. Homozygosity for inactivating mutations of HESX1 produces a complex phenotype that resembles septo-optic dysplasia. Much more needs to be learned about the role of HESX1 mutations in other forms of hypopituitarism.

Since growth hormone deficiency (GHD) causes short stature and metabolic derangements, the processes which control its release are important physiologically. These processes can be illuminated by an understanding of genetically determined GHD. In 2 Indian Moslem cousins from a consanguineous family, GHD resistant to growth hormone releasing hormone (GHRH) stimulation was found. No mutations were found in the growth hormone gene (GH1) (J. Phillips). The receptor for GHRH (GHRHR), implicated in the dwarfism of the little mouse, thus becomes a candidate gene to explain their GHD. Amplification and sequencing a region of GHRHR homologous to that mutated in the little mouse showed a mutation (265G*T) leading to a stop codon at position 72 which would completely prevent GHRHR expression. Subsequently, Maheshwari et al. found an identical mutation in a multiplex kindred from Sindh, Pakistan, about 800 km from the place of origin of our patients. GHD is more commonly caused by recessive or dominant mutations of GH1. The latter are of great interest in understanding the mechanism of GH secretion. In a large kindred with dominant GHD we found a heterozygous 666G*A mutation replacing of Arg with His at amino acid 183. We speculate that the introduced histidine interferes with interactions necessary for correct GH secretion.