The Long-Term Effects of Growth Hormone Replacement on Bone Mineral Density and Trabecular Bone Score: Results of the 10-Year Prospective Follow-up

There are only few studies concerning about long-term effect of growth hormone (GH) replacement therapy on bone mineral density and bone microstructure. To assess effect of GH replacement therapy on bone mineral density (BMD) and trabecular bone score (TBS) in adult GH deficient (AGHD) subjects over period of 10 years. From 2005 to 2018, a prospective study of AGHD patients was conducted in national referral center for treatment of GHD. All patients received subcutaneous recombinant human GH in an IGF 1-normalizing regimen once a day. Lumbar spine (L-spine) and total hip (TH) BMD using Hologic densitometers were measured at baseline and every two years during treatment with rhGH. TBS was derived from L1-L4 DXA using iNsight® software (Medimaps, France) at each time point. Periods of measurement were baseline, year 2; 4; 6; 8 and 10. In total, 63 patients (38 males, 25 females, mean age 25.1±16 years) were included in the study. After 10 years of GH treatment, IGF-1 significantly increased (~35 %), with greatest increase at year 2. During 10-year follow-up, L-spine BMD increased approximately of 7 % (NS). TH BMD increase of 11 % during follow-up (p=0.0003). The greatest increment of BMD was achieved at year 6 on both sites, L-spine (+6 %) and TH BMD (+13 %) (p<0.05). There was no significant change of TBS during whole follow-up. In this study, sustaining positive effect of GH replacement therapy on bone density in subjects with adult GH deficiency over 10 years of follow-up was observed. The study did not show effect on TBS, as indirect measure of trabecular bone microarchitecture.

Patients with adult GH deficiency should receive GH replacement – Debate

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Diagnosis and Treatment of Adult Growth Hormone Deficiency

Adult growth hormone (GH) deficiency is associated with insulin resistance, elevated cardiovascular risk profile, increased fat mass, reduced muscle mass, skeletal fragility, and impaired quality of life. GH replacement therapy improves body composition, exercise capacity, skeletal health, cardiovascular outcomes, and quality of life, while reducing mortality. Prior to initiation of GH replacement therapy, it is essential to diagnose GH deficiency via a GH stimulation test in adults suspicious of such deficiency. Therapy should be started using (individualized) low dose of GH, followed by titration to the normal range of insulin-like growth factor-1. Clinical improvements should be monitored and side effects should be minimized.

Safety of growth hormone (GH) treatment in GH deficient children and adults treated for cancer and non-malignant intracranial tumors—a review of research and clinical practice

Individuals surviving cancer and brain tumors may experience growth hormone (GH) deficiency as a result of tumor growth, surgical resection and/or radiotherapy involving the hypothalamic-pituitary region. Given the pro-mitogenic and anti-apoptotic properties of GH and insulin-like growth factor-I, the safety of GH replacement in this population has raised hypothetical safety concerns that have been debated for decades. Data from multicenter studies with extended follow-up have generally not found significant associations between GH replacement and cancer recurrence or mortality from cancer among childhood cancer survivors. Potential associations with secondary neoplasms, especially solid tumors, have been reported, although this risk appears to decline with longer follow-up. Data from survivors of pediatric or adult cancers who are treated with GH during adulthood are scarce, and the risk versus benefit profile of GH replacement of this population remains unclear. Studies pertaining to the safety of GH replacement in individuals treated for nonmalignant brain tumors, including craniopharyngioma and non-functioning pituitary adenoma, have generally been reassuring with regards to the risk of tumor recurrence. The present review offers a summary of the most current medical literature regarding GH treatment of patients who have survived cancer and brain tumors, with the emphasis on areas where active research is required and where consensus on clinical practice is lacking.

GH Replacement in the Elderly: Is It Worth It?

Growth hormone (GH), once the age of linear growth is completed, continues to play a fundamental role for the human body. In adulthood, GH contributes to regulate muscle, cardiovascular and bone metabolism. The same happens in old age, although there is less data on the effect of GH in the elderly. Regardless the age of onset, a reduced quality of life (QoL), an increased cardiovascular risk and an accelerated age-related decline in physical strength have been demonstrated in the elderly with GH deficiency (EGHD). In adults with GH deficiency (AGHD), recent studies suggest a role of GH replacement therapy (GHrt) in improving lean/fat mass ratio, blood pressure, lipid profile, bone metabolism and QoL. Despite these recent studies, there is still a lack of randomized controlled trials proving these positive effects in EGHD. Moreover, the lack of a long-term positive outcome on mortality, and the cost of GHrt could often impact on treatment decision-making and lead to postpone or avoid the prescription. The aim of this mini-review is to summarize the available data on GHrt in EGHD, in order to highlight its weaknesses and strengths and to provide directions to clinicians that will help in the management of this specific set of patients.

A Case With Adult GH Deficiency Complicated With Osteogenesis Imperfecta: Effect of GH Replacement on Bone Mineral Density

Background: Osteogenesis imperfecta (OI) is an inherited connective tissue disorder with many phenotypic presentations. Bisphosphonates are the mainstay of pharmacologic fracture prevention therapy, although they aren’t officially approved for the treatment of OI. Clinical Case: The patient was born by breech delivery. After he had multiple fractures at the age of two years, he was diagnosed with osteogenesis imperfecta (OI) type I by genetic analysis (c.1299 + 1G&gt; A mutation in the COL1A1 gene). On the growth curve, his height fell below -2SD at the age of six years. When he was 12 years old, he visited another hospital because of short stature (Hight 119 cm: -2.7SD). Pituitary MRI revealed pituitary stalk disruption and pituitary atrophy. Endocrinological examinations (ITT, TRH, LHRH, arginine stimulation tests) showed severe GH deficiency. Growth hormone replacement therapy was started. At the age of 16 years, he was diagnosed to have central hypothyroidism and central diabetes insipidus, and levothyroxine and DDAVP were started. His bone mineral density of the lumbar spine was 0.546 g/cm2, and alendronate was started. At the age of 17, central hypogonadism was diagnosed by LHRH stimulation test, and HCG injections were initiated. His bone mineral density continued to increase by GH replacement, HCG injections and bisphosphonate and reached 0.820 g/cm2 (Z-score: -0.27) by the age of 18 years. GH replacement was discontinued (final height 180 cm). At that age, his bone mineral density declined to 0.717 g/cm2 at the age of 25 years, although he stayed on an alendronate and HCG injections. At that time, total testosterone 890 ng/dL (142&lt;n&lt;923 ng/dL) was within normal range, but IGF-1 level was below the lower limit (44 ng/mL; -4.6SD, 225&lt;n&lt;337 ng/mL). He was referred to our hospital for transition to adult endocrine care. Endocrinologic evaluation revealed low serum cortisol level in the early morning (2.26 µg/dL, 7.07&lt;n&lt;19.6 μg/dL). GH-releasing peptide-2 stimulation test revealed severe GH deficiency (peak GH 0.18 ng/mL, n&gt; 15 ng/mL (1)) and replacements with GH and hydrocortisone were initiated. After the GH replacement, the bone mineral density started to increase to 0.954 g/cm2 (Z-score: -0.5). Conclusion: So far as we know, this is the first case report of OI with panhypopituitarism treated with GH and bisphosphonate. This case suggests that bisphosphonate alone is not sufficient to maintain bone mineral density complicated with both OI and severe GHD. GH replacement therapy was inevitable to increase bone mineral density in this patient. Reference: (1) Kazuo Chihara et al. A simple diagnostic test using GH-releasing peptide-2 in adult GH deficiency. Eur J Endocrinol.2007;157;19-27.

Design of the ForesiGHt Trial: A Multicenter, Randomized, Placebo- and Active-Controlled Trial to Compare Once-Weekly TransCon hGH (lonapegsomatropin) to Placebo and Daily Somatropin in Adults With Growth Hormone Deficiency (GHD)

BackgroundAdult GHD results from insufficient growth hormone (GH) secretion from the anterior pituitary gland and may represent either a continuation of childhood-onset GHD or GHD acquired during adulthood. Clinically, adult GHD is associated with central adiposity, decreased lean muscle mass, increased fat mass, decreased bone mineral density, and reduced quality of life. Current standard of care consists of GH replacement via daily injections. Lonapegsomatropin is a long-acting prodrug of somatropin (hGH), designed to deliver unmodified hGH with a weekly exposure profile. Lonapegsomatropin consists of somatropin that is transiently bound to a carrier via a proprietary TransCon Linker. The carrier extends the duration of somatropin in the circulation through a shielding effect that minimizes renal excretion and receptor-mediated clearance of the prodrug. At physiologic conditions, lonapegsomatropin releases fully active, unmodified somatropin via autocleavage of the linker in a controlled manner. The safety and efficacy of lonapegsomatropin have previously been evaluated in two phase 3 trials and one long-term extension trial in pediatric GHD. Changes in body composition are an objective and sensitive endpoint that reflects biologic activity of GH and clinical efficacy of GH replacement. Methods: The primary objective of the foresiGHt trial is to evaluate the efficacy of once-weekly lonapegsomatropin compared to placebo at 38 weeks in adults with GHD. The trial will be conducted at approximately 120 sites in North America, Europe, Asia, and Oceania. Approximately 240 subjects will be randomized 1:1:1 to once-weekly lonapegsomatropin, once-weekly placebo, or daily somatropin (Norditropin®). Subjects will be treatment-naïve or without GH therapy for at least 12 months. Subjects with well-controlled non-insulin dependent diabetes mellitus (HbA1c ≤ 7.5%) will be eligible. Following screening, the 38-week treatment period will consist of a 12-week gradual dose titration period and 26 weeks of fixed dose maintenance. Fixed dosing will be used to ensure maximal comparability across the treatment arms in the trial. Three dosing groups per arm will be established to allow for differences in age and oral estrogen intake in women. The primary endpoint is change from baseline in trunk percent fat at week 38, as measured by dual energy X-ray absorptiometry (DXA). Secondary efficacy endpoints are change from baseline in trunk fat mass and change in total body lean mass at week 38. Exploratory efficacy endpoints include total body fat mass, trunk lean mass, visceral adipose tissue, and patient-reported outcomes. Conclusion: The ongoing global phase 3 foresiGHt trial is designed to assess the efficacy, safety, and tolerability of lonapegsomatropin by weekly administration, compared to weekly placebo and daily hGH replacement therapy in adults with GHD.

Pregnancy outcomes in women receiving growth hormone replacement therapy enrolled in the NordiNet® International Outcome Study (IOS) and the American Norditropin® Studies: Web-Enabled Research (ANSWER) Program

Purpose Data on the safety of growth hormone (GH) replacement therapy during pregnancy are limited. We report a combined analysis of data from pregnant women treated with GH while enrolled in two non-interventional, multicenter studies: NordiNet® International Outcome Study (IOS) and the American Norditropin® Studies: Web-Enabled Research (ANSWER) Program. Methods Pregnancy data were pooled from NordiNet® IOS and the ANSWER Program. Data were collected during routine clinic visits by participating physicians using a web-based system. Patients exposed to GH replacement therapy during pregnancy were included in the analysis. Results The study population included 40 female patients with typical causes of adult GH deficiency (GHD). Overall, there were 54 pregnancies. Of these, 47 were exposed to GH between conception and delivery. In 48.9% of pregnancies exposed to GH, the dose was > 0.6 mg/day. GH was continued past conception and then stopped during the first, second, and third trimester, in 27.7%, 17.0%, and 2.1% of pregnancies, respectively. In 29.8%, GH was continued throughout pregnancy, with an unchanged dose in most cases. Of the 47 GH-exposed pregnancies, 37 (78.7%) progressed to normal delivery. There were three adverse events reported in two pregnancies. Conclusion These real-world data suggest that there were no new safety signals related to GH exposure in women with GHD during pregnancy. These results are consistent with findings from previous studies reporting data in pregnancies exposed to GH at conception or throughout pregnancy. This observational study in additional pregnancies provides further evidence that GH exposure does not adversely affect pregnancy outcome. Clinical trial registration: ClinicalTrials.gov NCT00960128 (date of registration: August 13, 2009) and NCT01009905 (date of registration: November 5, 2009).

Adult growth hormone deficiency guidelines: more difficult than it seems to incorporate into clinical practice universally

Adult growth hormone deficiency (GHD) is a syndrome characterized by adverse phenotypic, metabolic, and quality-of-life features. Over the past 2 decades, there is accumulating evidence demonstrating improvement of most of these parameters when GH is optimally replaced. Appropriate selection of patients at risk of GHD is crucial when considering and performing appropriate testing to establish the diagnosis. While generally safe, GH replacement requires careful dose initiation and monitoring to assure effectiveness and tolerance in treated patients. Several consensus clinical practice guidelines recommend evaluation of adults presenting with pituitary disorders for GHD. However, the clinical practice of managing such patients varies among countries largely due to lack of recognition of the condition, lack of GH availability, and lack of reimbursement of the drug, as demonstrated from a large online survey prepared by the European Society of Endocrinology involving 2148 patients from Europe and Australia. These data reinforce the notion of the large variability of disease recognition, clinical practice and education of adult GHD amongst healthcare professionals, and the lack of availability and reimbursement of the drug contributing to the under-utilization of GH replacement therapy in several countries. This commentary article highlights the fact that despite the publication of several guideline recommendations and positive long-term safety and efficacy data of GH replacement, there is still a need for increased education to enhance the awareness in the general population and improve the knowledge of healthcare professionals and administrators of adult GHD as a disease state to allow for early identification and treatment optimization.