Sensitivity and specificity of the macimorelin test for diagnosis of AGHD.

OBJECTIVE: The macimorelin test is approved for the diagnosis of adult growth hormone deficiency (AGHD) based on its efficacy vs the insulin tolerance test (ITT). Macimorelin has a significant advantage over ITT in avoiding hypoglycemia. Analyses were conducted to determine whether macimorelin performance is affected by age, BMI, or sex, and evaluate its performance vs ITT over a range of GH cutpoints. DESIGN: Post hoc analyses of data from a previous randomized phase 3 study included participants aged 18-66 years with BMI <37 kg/m2 and high (Group A), intermediate (Group B), or low (Group C) likelihood for AGHD based on pituitary history, and matched controls (Group D). METHODS: Probability of AGHD was estimated using unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted logistic models. Area under the curve (AUC) of the estimated receiver operating characteristic (ROC) curve (range, 0-1; 1 = perfect) was compared for adjusted vs unadjusted models. Separate analyses evaluated agreement, sensitivity, and specificity for macimorelin and ITT using cutpoints of 2.8, 4.0, 5.1, and 6.5 ng/mL. RESULTS: For participants in Group A (n = 41) and Group D (n = 29), unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted models had ROC AUCs (95% CIs) of 0.9924 (0.9807-1), 0.9924 (0.9807-1), 0.9916 (0.9786-1), and 0.9950 (0.9861-1), respectively. CONCLUSIONS: Macimorelin performance was not meaningfully affected by age, BMI, or sex, indicating robustness for AGHD diagnosis. Of the 4 GH cutpoints evaluated, the cutpoint of 5.1 ng/mL provided maximal specificity (96%) and high sensitivity (92%) and was in good overall agreement with the ITT at the same cutpoint (87%).

Thorough QT/QTc Study Evaluating the Effect of Macimorelin on Cardiac Safety Parameters in Healthy Participants.

Macimorelin is an orally active growth hormone secretagogue indicated for the diagnosis of adult growth hormone deficiency. The primary objective of this study was to evaluate the effect of macimorelin on the baseline and placebo-corrected mean QT interval using Fridericia's formula (ΔΔQTcF). Secondary objectives were to determine QTcF for moxifloxacin; evaluate the effects of macimorelin on other cardiac intervals (PR, QRS, RR), heart rate, and electrocardiogram morphology parameters; characterize pharmacokinetics; and assess safety of macimorelin. The phase 1 thorough QT/QTc study, designed according to the International Council for Harmonisation E14 guideline, was a randomized, placebo-controlled, double-blind, 3-way complete crossover study comparing the effect of macimorelin 2.0 mg/kg with placebo and moxifloxacin 400 mg (positive control). Data were collected over a 3-month span from male (n=36) and female participants (n=24) aged 18 to 55 years with body mass index between 18.5 and 30.0 kg/m2 . Fifty-six participants received all 3 treatments. The ΔΔQTcF for macimorelin showed a prolongation with a maximum mean value of 9.61 milliseconds (2-sided 90% confidence interval, 7.81 milliseconds and 11.41 milliseconds) at 4 hours after dosing. The 2-sided 90% confidence interval of this value also exceeded the 10 millisecond threshold at 3 hours after dosing. Assay sensitivity was confirmed with moxifloxacin. Other electrocardiogram parameters evaluated were not influenced by macimorelin. Macimorelin did not raise other safety concerns and was well tolerated. In summary, a single supratherapeutic dose of macimorelin prolonged cardiac repolarization according to the regulatory guideline.

Outcomes in children treated with growth hormone for Prader-Willi syndrome: data from the ANSWER Program® and NordiNet® International Outcome Study.

BACKGROUND: Growth hormone (GH) deficiency is common in patients with Prader-Willi syndrome (PWS) and leads to short adult stature. The current study assessed clinical outcomes based on real-world observational data in pediatric patients with PWS who were treated with GH. METHODS: Data from patients previously naïve to treatment with GH who began therapy with somatropin were collected from 2006 to 2016 in the observational American Norditropin® Studies: Web-Enabled Research (ANSWER) Program® and NordiNet® International Outcome Study. Variables affecting change from baseline in height standard deviation scores (HSDS; n = 129) and body mass index standard deviation scores (BMI SDS; n = 98) were determined. RESULTS: Patients included in both HSDS and BMI SDS analyses were treated with a mean GH dose of 0.03 mg/kg/d (SD, 0.01 mg/kg/d). Results from the HSDS analysis revealed that baseline age and years on treatment had a significant impact on the change in HSDS. In the BMI SDS analysis, longer GH treatment time led to a greater change in BMI SDS from baseline, and patients with a higher BMI at the start of treatment had a greater decrease in BMI over time. CONCLUSIONS: GH is effective in the management of children with PWS. Earlier treatment resulted in a greater gain in height, and a longer treatment period resulted in better outcomes for both height and BMI. TRIAL REGISTRATION: This study was registered with ClinicalTrials.gov ( NCT01009905 ) on November 9, 2009.

Height outcomes in children with growth hormone deficiency and idiopathic short stature treated concomitantly with growth hormone and aromatase inhibitor therapy: data from the ANSWER program.

BACKGROUND: Treatment of children with growth hormone deficiency (GHD) or idiopathic short stature (ISS) using GH is only effective for bone growth prior to epiphyseal fusion. Aromatase inhibitor therapy (AIT) blocks estrogen production, thereby delaying epiphyseal fusion. The current study analyzed baseline characteristics and longitudinal data of male patients with GHD or ISS who were treated with GH and concomitant AIT. METHODS: Data were obtained from the observational American Norditropin® Studies: Web-Enabled Research (ANSWER) Program, which collected efficacy and safety data of patients treated with Norditropin®. A longitudinal cohort approach compared patient characteristics, including chronologic age, bone age, and height standard deviation score (HSDS), in GH-treated males before and after AIT initiation. RESULTS: A total of 142 GH-naïve patients with GHD (n = 115) or ISS (n = 27) with mean (± SD) baseline chronological ages of 12.10 ± 3.00 and 10.76 ± 3.07 years, respectively, were analyzed. The majority were classified at advanced Tanner stages II to V. Patients with GHD had mean HSDS of - 1.97 ± 0.78 at baseline and - 0.99 ± 0.88 prior to AIT initiation, while corresponding values for patients with ISS were - 2.15 ± 0.72 and - 1.04 ± 0.79, respectively. In patients evaluated after 2 years of concomitant AIT, mean HSDS had decreased to - 0.40 ± 1.16 and - 0.65 ± 0.52 for patients with GHD and ISS, respectively. Patients with GHD had a mean bone age/chronological age ratio (BA/CA) of 0.91 ± 0.11 at baseline and 0.97 ± 0.10 prior to AIT initiation, while corresponding values for patients with ISS were 0.85 ± 0.16 and 0.99 ± 0.10, respectively. In patients evaluated after 2 years of concomitant AIT, mean BA/CA values were 0.95 ± 0.10 and 0.96 ± 0.06 for patients with GHD and ISS, respectively. CONCLUSIONS: In this real-world analysis, use of AIT with GH in males appeared to be associated with ongoing growth over 2 years, and AIT likely augmented growth potential as indicated by continued HSDS increase with decreased BA/CA after AIT initiation. TRIAL REGISTRATION: This trial was sponsored by Novo Nordisk and is registered with ClinicalTrials.gov (NCT01009905). Registered November 11, 2009; retrospectively registered.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of macimorelin in healthy adults: Results of a single-dose, randomized controlled study.

OBJECTIVE: Macimorelin is an orally active ghrelin receptor agonist indicated for the diagnosis of adult growth hormone (GH) deficiency in the United States. This phase 1 study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of single ascending doses of macimorelin (including a supratherapeutic dose to be used in a thorough QT trial) in healthy adults. DESIGN: Participants were randomized to receive macimorelin 0.5, 1.0, or 2.0 mg/kg or placebo in 1 of 3 sequential ascending-dose cohorts. Blood samples for pharmacokinetic and pharmacodynamic assays were collected pre-dose and at specified time points over a 24-h period. Pharmacokinetic parameters assessed included area under the concentration-time curve (AUC), maximum concentration (Cmax) of macimorelin in plasma, time to Cmax (tmax), and terminal elimination half-life (t1/2). Pharmacodynamic assessments evaluated levels of GH, adrenocorticotropic hormone, thyroid-stimulating hormone, cortisol, and prolactin. Safety was assessed based on treatment-emergent adverse events (TEAEs), vital signs, 12­lead electrocardiograms, and laboratory parameters. RESULTS: A total of 28 healthy adults were enrolled and completed the study. Macimorelin AUC and Cmax showed less than dose-proportional increases following administration of 0.5 and 1.0 mg/kg. Mean t1/2 was 3.51 h for macimorelin 0.5 and 1.0 mg/kg and 8.29 h for macimorelin 2.0 mg/kg; median tmax occurred at 0.5 to 0.75 h. GH levels increased after dosing, with a tmax of 0.75 h to 1.0 h. Mean GH Cmax was similar with the macimorelin 0.5- and 1.0-mg/kg doses (31.9 and 37.8 ng/mL, respectively) and was ~50% lower with macimorelin 2.0 mg/kg (18.4 ng/mL). Transient increases were observed in adrenocorticotropic hormone, cortisol, and prolactin, which were not dose related. A total of 19 TEAEs were reported in 35.7% (10/28) of participants; all TEAEs were mild or moderate and resolved. A total of 12 drug-related TEAEs were reported in 8 participants. Headache was the most common drug-related TEAE. All doses of macimorelin prolonged mean QTcF by 10 to 11 ms. There were no clinically meaningful changes in vital signs or laboratory parameters. CONCLUSIONS: Single-dose administration of macimorelin 0.5 to 2.0 mg/kg was well tolerated. Macimorelin exposure was less than dose-proportional over the dose range studied. Administration of macimorelin stimulated GH production, with the greatest increases observed in the macimorelin 0.5- and 1.0-mg/kg groups.

Awareness, Care and Treatment In Obesity maNagement to inform Haemophilia Obesity Patient Empowerment (ACTION-TO-HOPE): Results of a survey of US patients with haemophilia and obesity (PwHO) and their partners and caregivers.

BACKGROUND: The ACTION study identified barriers to initiating and maintaining weight loss in patients with obesity; however, joint-related issues (pain, mobility and bleeding) may affect perceptions of patients with haemophilia and obesity (PwHO). AIM: To identify patient and caregiver insights on the unique challenges of PwHO. METHODS: Following IRB approval, adults who self-identified as PwHO, spouses/partners of adult PwHO, and caregivers of adolescent PwHO (aged 12-17 years) completed an online survey between December 2017 and April 2018. RESULTS: Respondents included 124 adult PwHO, 45 spouses/partners and 42 caregivers. By calculated BMI, most adults were overweight (43%) or had obesity (51%); this differed from self-reported weight category. PwHO goals were improving health conditions (60%), having more energy (54%), reducing risks of weight (46%), and losing any weight (44%). Issues related to joint health were secondary for PwHO but frequently reported by spouses/parents. Most perceived weight loss to be a high priority (66%) and their responsibility (64%) but required a complete lifestyle change (63%). Most anticipated that weight loss would reduce joint pain (62%), bleeding (58%) and factor use (52%) and increase mobility (62%). Weight discussions with healthcare providers (HCPs) were commonly reported (51%). HCP discussions targeted improving health conditions (46%), achieving any weight loss (44%), being more active (73%) and improving eating habits (72%). Most PwHO (65%) perceived obesity as a disease and believe that 10% weight loss would be extremely beneficial (78%). In the past 5 years, 80% discussed being overweight and 68% losing weight; a minority reported being successful (9%) or somewhat successful (38%) with weight loss. More realistic or specific (51%/47%) goals, resources (46%), referrals to weight-loss programmes (41%) or dietitians (38%), meals or recipes (54%/50%), local or national (42%/41%) programmes for PwHO and success stories of PwHO (40%) are needed or would be helpful. CONCLUSIONS: PwHO, spouse/partners and caregivers exhibited awareness of general and haemophilia-specific consequences of excess body weight. Most have tried general approaches to improve eating and increase activity with little success and desire more education on weight management and more details on specific actionable recommendations distributed through existing haemophilia channels. These insights will better inform the creation of weight-loss programmes for this community.

Growth hormone replacement in adults: Real-world data from two large studies in US and Europe.

OBJECTIVE: This report describes the effectiveness and safety of growth hormone replacement in 3180 adult patients with growth hormone deficiency followed-up for 0.0-12.2 years in two completed, complementary, non-interventional, multicentre studies, NordiNet® International Outcome Study (IOS) (NCT00960128) and the American Norditropin® Studies: Web-Enabled Research (ANSWER) Program (NCT01009905). DESIGN: In both studies, Norditropin® (somatropin; Novo Nordisk A/S, Denmark) was administered at the discretion of the treating physician and according to routine practice. We present data on baseline characteristics, growth hormone dose, safety data and change from baseline in waist circumference, body mass index and bioimpedance (NordiNet® IOS only). RESULTS: Mean (SD) baseline characteristics (effectiveness analysis set) in NordiNet® IOS (n = 971) and ANSWER (n = 304): females, 45%; 69%; mean growth hormone dose (mg/day) (female, 0.338 [0.177]; male, 0.289 [0.157]); (female, 0.501 [0.313]; male, 0.505 [0.351]). Most patients had BMI ≥25 kg/m2. Median (P10,P90) exposure (females, 3.5 [0.42,11.0]; 1.6 [3.2; 0.3,8.6]; males, 4.1 [0.33,10.8]; 2.3 [2.9; 0.0,7.5] years). Mean (SD) change from baseline for waist circumference (-0.46 [6.38] cm [n = 403], BMI (0.30 [3.30] kg/m2 [n = 857]) and bioimpedance (-17.4 (59.19) ohm [n = 239]) were associated with growth hormone dose (waist/bioimpedance) and duration of follow-up (BMI/bioimpedance). No new safety signals were observed among patients in the full analysis set (NordiNet® IOS, n = 2321; ANSWER, n = 859). CONCLUSIONS: Long-term growth hormone replacement is associated with an improvement in body composition. The accumulated data from >10 years of follow-up support the long-term effectiveness and safety of growth hormone replacement as prescribed in clinical practice.

Long-Term Effectiveness and Safety of Childhood Growth Hormone Treatment in Noonan Syndrome.

INTRODUCTION: Few data exist on long-term growth hormone (GH) treatment in patients with Noonan syndrome (NS). OBJECTIVE: To evaluate the effectiveness and safety of GH treatment in NS in clinical practice. METHODS: Height gain, near-adult height (NAH), and safety were assessed in 2 complementary non-interventional studies: NordiNet® IOS and ANSWER. The safety analysis included 412 patients, and the effectiveness analysis included 84 GH-treated patients (male, n = 67) with ≥4 years' height standard deviation score (HSDS) data. HSDS was determined using national reference (NR) and NS-specific (NSS) data. RESULTS: The mean (SD) baseline age was 8.38 (3.57) years; HSDS, -2.76 (1.03); GH dose, 41.6 (11.1) µg/kg/day. The mean (SD) HSDS increase from baseline (ΔHSDS) was 0.49 (0.37) (first year), 0.79 (0.58) (second year), and 1.01 (0.60) (third year) (NR). The mean (SD) HSDS at year 3 was -1.66 (1.00) (NR; 1.06 [1.12] [NSS]). Twenty-four patients achieved NAH. The mean (SD) NAH SDS (NR) was -1.51 (0.60) (154.90 [3.21] cm) in females and -1.79 (1.09) (165.61 [7.19] cm) in males; 70.8% (17/24) had NAH SDS ≥ -2. Adverse drug reactions and GH-unrelated serious adverse events (n = 34) were reported in 22/412 (5.3%) patients. Four neoplasms and 3 cases of scoliosis were reported; no cardiovascular adverse events occurred. CONCLUSIONS: GH-treated children with NS achieved substantial height gain during the first 3 years of follow-up. Overall, 24 patients achieved NAH, with 70.8% having NAH SDS ≥ -2. There was no evidence to support a higher prevalence of neoplasm, or cardiac or other comorbidities.

Treatment of Children With GH in the United States and Europe: Long-Term Follow-Up From NordiNet® IOS and ANSWER Program.

CONTEXT: Understanding real-world prescribing of GH may help improve treatment of eligible patients. OBJECTIVE: Overall: to assess real-world effectiveness and safety of GH (Norditropin). This analysis: to compare clinical characteristics of GH-treated children in the United States and Europe. DESIGN: The American Norditropin Studies: Web-Enabled Research Program (ANSWER; 2002 to 2016, United States) and the NordiNet International Outcome Study (NordiNet IOS; 2006 to 2016, Europe) were multicenter longitudinal observational cohort studies. SETTING: Data were recorded in 207 (United States) and 469 (Europe) clinics. PARTICIPANTS: Patients with GH deficiency, Turner syndrome, Noonan syndrome, idiopathic short stature, Prader-Willi syndrome, or born small for gestational age, who commenced GH treatment aged <18 years. INTERVENTION: GH was prescribed by treating physicians according to local practice. MAIN OUTCOMES MEASURES: Baseline data and drug doses were recorded. Data on effectiveness and safety were collected. RESULTS: ANSWER had 19,847 patients in the full analysis set (FAS; patients with birthdate information and one or more GH prescription) and 12,660 in the effectiveness analysis set (EAS; GH-naive patients with valid baseline information). NordiNet IOS had 17,711 (FAS) and 11,967 (EAS). Boys accounted for 69% (ANSWER) and 57% (NordiNet IOS). Treatment start occurred later than optimal to improve growth. The proportion of boys treated was generally larger, children were older at treatment start, and GH doses were higher in the United States vs Europe. No new safety signals of concern were noted. CONCLUSIONS: In most indications, more boys than girls were treated, and treatment started late. Earlier diagnosis of GH-related disorders is needed. The data support a favorable benefit-risk profile of GH therapy in children.

Growth hormone therapy in children born small for gestational age: results from the ANSWER program.

Growth hormone (GH) is used to treat short stature and growth failure associated with growth disorders. Birth size and GH status variably modulate response to GH therapy. The aim of this study was to determine the effect of birth size on response to GH therapy, and to determine the impact of GH status in patients born small for gestational age (SGA) on response to GH therapy. Data from the prospective, non-interventional American Norditropin® Studies: Web-Enabled Research (ANSWER) Program were analyzed for several growth outcomes in response to GH therapy over 3 years. GH-naïve children from the ANSWER Program were included in this analysis: SGA with peak GH ≥10 ng/mL (20 mIU/l), SGA with peak GH <10 ng/mL (20 mIU/l), isolated growth hormone deficiency (IGHD) born SGA, IGHD not born SGA, and idiopathic short stature. For patients with IGHD, those who did not meet criteria for SGA at birth showed greater improvements in height SDS and BMI SDS than patients with IGHD who met criteria for SGA at birth. For patients born SGA, response to GH therapy varied with GH status. Therefore, unlike previous guidelines, we recommend that GH status be established in patients born SGA to optimize GH therapy.

Insulin resistance secondary to a high-fat diet stimulates longitudinal bone growth and growth plate chondrogenesis in mice.

It is known that overweight children are often more insulin resistant and taller than normal-weight peers. Because it has been hypothesized that insulin is implicated in the obesity-associated growth acceleration, we aimed to determine whether insulin resistance and secondary hyperinsulinemia are the causative mechanisms of such growth acceleration. Three-week-old mice were fed with standard chow or with a high-fat diet without or with daily administration of pioglitazone. After 6 wk, high-fat mice' body and tibial growth, tibial growth plate height, and serum insulin were all greater than those of standard chow-fed mice. High-fat + pioglitazone mice were shorter, their tibial growth and the growth plate height reduced, and their insulin lower than those of high-fat mice. The addition of insulin to the culture medium of mouse metatarsal bones induced the metatarsal linear growth and increased the metatarsal growth plate height. In addition, insulin stimulated cultured chondrocyte proliferation and differentiation, with both effects being prevented by transfection with a small interfering RNA targeted to the insulin receptor. In conclusion, in high fat-fed mice, insulin resistance is causally related to accelerated skeletal growth. Our in vitro findings suggest that insulin may directly modulate skeletal growth by activating the insulin receptor directly at the growth plate.

Association between oxidative stress and masked hypertension in a multi-ethnic population of obese children and adolescents.

OBJECTIVE: To evaluate whether oxidative stress is correlated with adiposity, obesity-related metabolic abnormalities, and ambulatory blood pressure (ABP) in a multi-ethnic pediatric population. STUDY DESIGN: We conducted a prospective study enrolling 42 obese children (age, 12.8 ± 2.4 years) and 34 non-obese children (age, 11.8 ± 3.4 years). We measured urine 8-isoprostane and hydrogen peroxide (markers of oxidative stress) in both obese and non-obese groups. In the obese group, we measured the 24-hour ABP and obtained an oral glucose tolerance test, lipid panel, interleukin-6, and tumor necrosis factor-α. RESULTS: 8-isoprostane and hydrogen peroxide were correlated with body mass index standard deviation score and waist circumference. The mean 8-isoprostane and hydrogen peroxide levels of the obese group were higher than those of the non-obese group. In the subset of obese subjects who underwent ABP monitoring, 8-isoprostane was correlated with mean 24-hour systolic blood pressure: within the obese group, 8-isoprostane was higher in obese children with elevated mean 24-hour systolic blood pressure. CONCLUSIONS: Our findings provide evidence of a significant correlation between oxidative stress, adiposity, and blood pressure in children. Longitudinal studies in a larger population sample are needed to validate the association between elevated urine 8-isoprostane level and cardiovascular risk factors in an obese pediatric population.

Elevated ambulatory blood pressure in a multi-ethnic population of obese children and adolescents.

OBJECTIVES: To evaluate the relationship among ambulatory blood pressure (ABP), body mass index (BMI), and homeostasis model assessment (HOMA) in a multi-ethnic population of obese children with clinic blood pressure in the reference range. STUDY DESIGN: A total of 43 obese normotensive children (7-17 years old) were recruited. ABP monitoring, oral glucose tolerance test, lipid levels, and urine microalbumin levels were obtained. RESULTS: Fourteen percent of the subjects had elevated 24-hour systolic blood pressure (SBP), 9.3% had elevated daytime SBP, and 32.6 % elevated nighttime SBP. For diastolic blood pressure, 4.7% of the sample had an elevated mean nighttime value. Children with more severe obesity (BMI SD score >2.5) had higher 24-hour and nighttime SBP than children with less severe obesity (BMI SD score < or =2.5). Children with HOMA values in the highest quartile had larger waist circumference and higher clinic blood pressure than children with HOMA values in the lowest quartile, and no difference in the mean ABP values was found in the 2 groups . Multiple linear regression analysis showed that 24-hour and nighttime SBP were significantly correlated with BMI SD score. CONCLUSION: Obese children with normal clinic blood pressure often exhibit elevated ABP. The risk for ambulatory hypertension appears to be correlated with the degree of obesity.

Long term follow-up of a child with ambiguous genitalia, mixed gonadal dysgenesis, and unusual mosaicism.

Mixed gonadal dysgenesis (MGD) is a condition of abnormal and asymmetrical gonadal development. This disorder is typically associated with 45,X/46,XY mosaicism; however, other karyotypes have been rarely reported. The phenotype characterizing MGD is highly variable, although in most cases ambiguous genitalia are found. In addition, many individuals with MGD exhibit stigmata of Turner's syndrome. We describe a patient with MGD, found to have a 45,X/47,XYY karyotype, with the majority of the cell lines being 47,XYY. To our knowledge, our report is the first to describe the long-term follow-up of a patient with ambiguous genitalia diagnosed at birth with 45,X/47,XYY mosaicism.