Frontiers in congenital disorders of glycosylation consortium, a cross-sectional study report at year 5 of 280 individuals in the natural history cohort.

OBJECTIVE: Our report describes clinical, genetic, and biochemical features of participants with a molecularly confirmed congenital disorder of glycosylation (CDG) enrolled in the Frontiers in Congenital Disorders of Glycosylation (FCDGC) Natural History cohort at year 5 of the study. METHODS: We enrolled individuals with a known or suspected CDG into the FCDGC Natural History Study, a multicenter prospective and retrospective natural history study of all genetic causes of CDG. We conducted a cross-sectional analysis of baseline study visit data from participants with confirmed CDG who were consented into the FCDGC Natural History Study (5U54NS115198) from October 2019 to November 2023. RESULTS: Three hundred thirty-three subjects consented to the FCDGC Natural History Study. Of these, 280 unique individuals had genetic data available that was consistent with a diagnosis of CDG. These 280 individuals were enrolled into the study between October 8, 2019 and November 29, 2023. One hundred forty-one (50.4%) were female, and 139 (49.6%) were male. Mean and median age at enrollment was 10.1 and 6.5 years, respectively, with a range of 0.22 to 71.4 years. The cohort encompassed individuals with disorders of N-linked protein glycosylation (57%), glycosylphosphatidylinositol anchor disorder (GPI anchor) (15%), disorders of Golgi homeostasis, trafficking and transport (12%), dolichol metabolism disorders (5%), disorders of multiple pathways (6%), and other (5%). The most frequent presenting symptom(s) leading to diagnosis were developmental delay/disability (77%), followed by hypotonia (56%) and feeding difficulties (42%). Mean and median time between first related symptom and diagnosis was 2.7 and 0.8 years, respectively. One hundred percent of individuals in our cohort had developmental differences/disabilities at the time of their baseline visit, followed by 97% with neurologic involvement, 91% with gastrointestinal (GI)/liver involvement, and 88% with musculoskeletal involvement. Severity of disease in individuals was scored on the Nijmegen Progression CDG Rating Scale (NPCRS) with 27% of scores categorized as mild, 44% moderate, and 29% severe. Of the individuals with N-linked protein glycosylation defects, 83% of those with data showed a type 1 pattern on carbohydrate deficient transferrin (CDT) analysis including 82/84 individuals with PMM2-CDG, 6% a type 2 pattern, 1% both type 1 and type 2 pattern and 10% a normal or nonspecific pattern. One hundred percent of individuals with Golgi homeostasis and trafficking defects with data showed a type 2 pattern on CDT analysis, while Golgi transport defect showed a type II pattern 73% of the time, a type 1 pattern for 7%, and 20% had a normal or nonspecific pattern. Most of the variants documented were classified as pathogenic or likely pathogenic using ACMG criteria. For the majority of the variants, the predicted molecular consequence was missense followed by nonsense and splice site, and the majority of the diagnoses are inherited in an autosomal recessive pattern but with disorders of all major nuclear inheritance included. DISCUSSION: The FCDGC Natural History Study serves as an important resource to build future research studies, improve clinical care, and prepare for clinical trial readiness. Herein is the first overview of CDG participants of the FCDGC Natural History Study.

Development of specific growth charts for children with Fanconi anemia.

Patients with Fanconi anemia (FA) are often perceived to have poor growth when general population growth curves are utilized. We hypothesize that FA patients have unique growth and aimed to create FA-specific growth charts. Height and weight data from ages 0 to 20 years were extracted from medical records of patients treated at the Fanconi Anemia Comprehensive Care Clinic at the University of Minnesota. Height, weight, and BMI growth curves were generated and fitted to reference percentiles using the Lambda-Mu-Sigma method. FA-specific percentiles were compared to WHO standards for ages 0-2 and CDC references for ages 2-20. In FA males, the 50th height- and weight-for-age percentiles overlap with the 3rd reference percentile. In FA females, only the 50th height-for-age percentile overlaps with the 3rd reference percentile. For weight, FA females show progressive growth failure between 6 and 24 months followed by stabilization around the 50th percentile. The FA BMI-for-age percentiles show similar patterns to the weight-for-age percentiles but have different timing of onset of adiposity rebound and broader variability in females. Growth in FA patients follows a different trajectory than available normative curves. FA-specific growth charts may be useful to better guide accurate growth expectations, evaluations, and treatment.

Impact of Daily Growth Hormone Adherence on Height Velocity Among Children With Growth Hormone Deficiency (GHD).

OBJECTIVE: To describe adherence to daily somatropin treatment and impact on height velocity within 1 year of treatment start among patients with pediatric growth hormone deficiency in a real-world US population. METHODS: This retrospective cohort study included pediatric patients aged ≥3 years to <16 years with pediatric growth hormone deficiency prescribed somatropin by a pediatric endocrinologist at a US-based center of excellence between January 1, 2015 and December 31, 2020. Patient data were collected using hospital electronic health records linked to a specialty pharmacy patient prescription records. Adherence, evaluated over 12 months, was measured using the proportion of days covered metric and patients were categorized as adherent if their proportion of days covered ≥80%. Height velocity was annualized to compare across adherent and nonadherent patients. RESULTS: One hundred eighty-one patients were identified and included in this study, of which 70.2% were male,73.5% were white, and mean age (standard deviation [SD]) at index was 12.1 (2.8). In the height velocity analysis, 174 patients were included and the mean (SD) annualized change in height was 10.2 (5.7) cm/y in the adherent group (n = 108) and 9.8 (7.6) in the nonadherent group (n = 66). The difference in height velocity between the groups was not statistically significant. CONCLUSIONS: Minor improvements in average height velocity were observed in the patient group who were adherent to somatropin therapy, although not statistically significant. Lack of observed significance may be due to small sample sizes, short observation period, a likely heterogenous population in terms of growth hormone prescribing, data bias due to single-center origin, or potential patient misclassification.

Unstimulated Luteinizing Hormone for Assessment of Suppression during Treatment of Central Precocious Puberty with 6-Month Subcutaneous Leuprolide Acetate: Correlations with Clinical Response.

INTRODUCTION: Phase 3 trial of 6-month subcutaneous leuprolide acetate (SC-LA) in children with central precocious puberty (CPP) demonstrated efficacy and safety. The aims of this secondary analysis were to evaluate unstimulated luteinizing hormone (LH) as efficacy measure, assess clinical suppression metrics, and present biochemical and clinical data for subgroups not achieving hormone suppression. METHODS: Sixty-two children with treatment-naïve CPP received 2 doses of 45 mg SC-LA at 24-week intervals. Unstimulated and GnRH-stimulated LH, E2, and T concentrations were measured. Clinical measures included bone age (BA) and predicted adult height (PAH). RESULTS: Eighty-four percentage and 86% of children achieved unstimulated LH <1 IU/L at weeks 24 and 48, respectively. Of 8 children not achieving unstimulated LH <1 IU/L at week 24 that completed the study, all showed a lack of pubertal stage progression and stable/decreased BA to chronological age ratio (BA/CA). Received operating characteristic (ROC) analyses suggested unstimulated LH is a good diagnostic predictor of GnRH-stimulated LH <4 IU/L at weeks 24 and 48 (AUC = 0.88). Across all children, mean BA/CA improved from 1.4 (screening) to 1.3 (week 48) and mean PAH increased by 3 cm. Of 7 girls not achieving stimulated LH <4 IU/L at week 24, all achieved E2 <10 pg/mL, showed a lack of pubertal stage progression, and had stable or decreased BA/CA by week 48. Additionally, 6/7 had increased PAH by week 48 and 4 had unstimulated LH <1 IU/L. CONCLUSION: Unstimulated LH has value as an efficacy measure and concentrations <1 IU/L may be an adequate surrogate of treatment response in children with CPP. All children who completed the study had evidence of pubertal suppression.

Somatrogon injection for the treatment of pediatric growth hormone deficiency with comparison to other LAGH products.

INTRODUCTION: Somatrogon (NGENLA™) is a long-acting GH (LAGH) formulation that was approved in Canada in October 2021 for the treatment of pediatric growth hormone deficiency (GHD). Somatrogon has also received approval in Australia, Japan, the European Union, the USA, and the UK. Somatrogon is a glycoprotein that utilizes three copies of the C-terminal peptide of human chorionic gonadotropin to delay its clearance allowing for once-weekly administration. AREAS COVERED: The purpose of this article is to describe the development of somatrogon for treatment of individuals with GHD. Trials of somatrogon demonstrated positive efficacy results in adults (Phase 2) and children (Phase 2 and 3) with GHD including non-inferiority of height velocity compared to daily GH, with no concerning side effects. Growth responses, pharmacodynamics and safety data are compared to other LAGH products, lonapegsomatropin and somapacitan, in Phase 3 trials in pediatric GHD. EXPERT OPINION: New LAGH products, including somatrogon, have the potential to increase patient adherence as well as improve quality of life and clinical outcomes. Clinicians will need to identify the best candidates for LAGH therapy and understand how to safely monitor and adjust therapy. Long-term surveillance studies are necessary to demonstrate adherence, efficacy, cost-effectiveness, and safety of LAGH preparations.

Pediatric growth hormone deficiency: Understanding the patient and caregiver perspectives.

Childhood growth hormone deficiency (GHD) is a rare disorder associated with significant burden on both patients and caregivers. Although previous reports have detailed aspects of the burden experienced by patients and their caregivers, there is a paucity of first-hand information on the patient and caregiver journeys from their respective voices. To address this need, an advisory board meeting was conducted on September 30, 2022, with 4 pediatric patients with GHD and their caregivers to discuss their experiences prior to GHD diagnosis, during the diagnostic process, and during ongoing treatment with recombinant growth hormone. Feedback from patients and caregivers was reviewed by pediatric endocrinologists, who provided their own perspectives on the patient and caregiver journeys based on the information reported. Despite the small sample size, important insights were obtained: patients and caregivers reported remarkable growth benefits achieved with treatment, which provided strong motivation to remain adherent to daily injection regimens. Patient and caregiver accounts reflected wide variability between families in time from suspicion to diagnosis and in treatment challenges faced, ranging from practical issues such as handling and administration of medication to broader concerns about treatment access and continuity, as well as key knowledge gaps among patients, caregivers, and clinicians. Recommendations are provided to enhance the patient and caregiver journeys, including increasing development and availability of educational materials, providing opportunities for patient advocacy by clinicians and health care providers, and encouraging institutional improvements to ensure that patients continue to receive uninterrupted treatment during their critical period of growth.

Developments in the Management of Growth Hormone Deficiency: Clinical Utility of Somapacitan.

Growth hormone (GH) replacement therapy for growth hormone deficiency (GHD) in children and adults has for over 25 years, until recently, been administered as daily injections. This daily treatment regimen often incurs a burden to patients and caregivers, leading to high rates of non-adherence and, consequently, decreased treatment efficacy outcomes. To address this shortcoming, long-acting growth hormones (LAGHs) have been developed with the aim of reducing the burden of daily injections, thereby potentially improving treatment adherence and outcomes. Somapacitan (Sogroya®) (Novo Nordisk, Bagsværd, Denmark) is a LAGH currently approved for the treatment of adult and childhood GHD (AGHD and CGHD, respectively) in several countries. Other LAGHs, such as somatrogon (Ngenla®) (Pfizer, New York, United States) and lonapegsomatropin/TransCon GH (Skytrofa®) (Ascendis Pharma, Copenhagen, Denmark), are also currently approved and available for the treatment of CGHD in several countries. In this review, we will consider the method of protraction, pharmacokinetics (PK) and pharmacodynamics (PD), efficacy, and safety results of somapacitan in adult and pediatric trials and how these characteristics differ from those of the other aforementioned LAGHs. Additionally, the administration of somapacitan and timing of measurement of serum insulin-like growth factor-I (IGF-I) levels are summarized. Information on administration, advice on missed doses, and clinical guidelines are discussed, as well as identifying which patients are suitable for somapacitan therapy, and how to monitor and adjust dosing whilst on therapy.

Insights from an advisory board: Facilitating transition of care into adulthood in brain cancer survivors with acquired pediatric growth hormone deficiency.

OBJECTIVE: Children with growth hormone deficiency (GHD) face multiple challenges that can negatively impact the transition from pediatric to adult endocrinology care. For children with GHD resulting from brain cancer or its treatment, the involvement of oncology care providers and possible disease-related comorbidities add further complexity to this transition. DESIGN: An advisory board of pediatric and adult endocrinologists was convened to help better understand the unique challenges faced by childhood cancer survivors with GHD, and discuss recommendations to optimize continuity of care as these patients proceed to adulthood. Topics included the benefits and risks of growth hormone (GH) therapy in cancer survivors, the importance of initiating GH replacement therapy early in the patient's journey and continuing into adulthood, and the obstacles that can limit an effective transition to adult care for these patients. RESULTS/CONCLUSIONS: Some identified obstacles included the need to prioritize cancer treatment over treatment for GHD, a lack of patient and oncologist knowledge about the full range of benefits provided by long-term GH administration, concerns about tumor recurrence risk in cancer survivors receiving GH treatment, and suboptimal communication and coordination (e.g., referrals) between care providers, all of which could potentially result in treatment gaps or even complete loss of follow-up during the care transition. Advisors provided recommendations for increasing education for patients and care providers and improving coordination between treatment team members, both of which are intended to help improve continuity of care to maximize the health benefits of GH administration during the critical period when childhood cancer survivors transition into adulthood.

Longitudinal clinical manifestations of Fanconi anemia: A systematized review.

Fanconi anemia (FA) is a rare and complex inherited genetic disorder characterized by impaired DNA repair mechanisms leading to genomic instability. Individuals with FA have increased susceptibility to congenital anomalies, progressive bone marrow failure, leukemia and malignant tumors, endocrinopathies and other medical issues. In recent decades, steadily improved approaches to hematopoietic cell transplantation (HCT), the only proven curative therapy for the hematologic manifestations of FA, have significantly increased the life expectancy of affected individuals, illuminating the need to understand the long-term consequences and multi-organ ramifications. Utilizing a systematized review approach with narrative synthesis of each primary issue and organ system, we shed light on the challenges and opportunities for optimizing the care and quality of life for individuals with FA and identify knowledge gaps informing future research directions.

Targeting VEGF-mediated blood-brain barrier disruption in advanced cerebral leukodystrophy.

The earliest clinical manifestation of cerebral adrenoleukodystrophy (CALD) is adrenal insufficiency (AI) characterized by elevations in ACTH and loss of cortisol. We showed high (though physiologically achievable) levels of ACTH increases endothelial permeability, increases anisotropy, and increases VEGF secretion. An ACBD1 knockout endothelial cell line had increased sensitivity to ACTH and VEGF. Inhibition of VEGF via application of anti-VEGF (bevacizumab) improved permeability. Six boys with advanced CALD were treated with bevacizumab combined with dexamethasone and ruxolitinib as immune suppressants. Most boys had decreases in gadolinium enhancement on MRI indicating improvement in endothelial function, though all boys continued to progress symptomatically.