Once-Weekly Administration of Sustained-Release Growth Hormone in Korean Prepubertal Children with Idiopathic Short Stature: A Randomized, Controlled Phase II Study

Long acting growth hormone (LAGH), an update

In 1957, Maurice Raben at Yale was able to isolate and purify growth hormone from cadaveric pituitary glands. Pituitary growth hormone was the only way to treat children with growth hormone (GH) deficiency, until 1985 when recombinant GH became available for daily subcutaneous injection. For many years, the pediatric endocrine community longed for a long-acting recombinant GH formulation that would decrease the inconvenience of daily injections. Several mechanisms were employed to develop a GH that is rapidly absorbed into the blood stream after subcutaneous injection, but provides slow removal from the circulatory system to potentially optimize patient adherence to GH therapy. Four long-acting growth hormones are currently available in the world, or are close to regulatory approval. They are: (1) Pegylated formulations, (2) Prodrug formulations which are converted into active drug, (3) Nonvalent transient albumin binding GH compounds and (4) GH fusion proteins where a protein si fused with GH. All four formulations have undergone detailed phase 3 studies and were found to show non-inferiority in these clinical studies. All four demonstrate a safety and tolerability profile that is comparable to that of daily somatropin with an excellent adherence profile.

Growth hormone receptor agonists and antagonists: From protein expression and purification to long-acting formulations

Recombinant human growth hormone (rhGH) and GH receptor antagonists (GHAs) are used clinically to treat a range of disorders associated with GH deficiency or hypersecretion, respectively. However, these biotherapeutics can be difficult and expensive to manufacture with multiple challenges from recombinant protein generation through to the development of long-acting formulations required to improve the circulating half-life of the drug. In this review, we summarize methodologies and approaches used for making and purifying recombinant GH and GHA proteins, and strategies to improve pharmacokinetic and pharmacodynamic properties, including PEGylation and fusion proteins. Therapeutics that are in clinical use or are currently under development are also discussed.

Comparing Dose-dependent Outcomes of Weekly and Daily Growth Hormone Therapy in Children with Growth Hormone Deficiency: A Systematic Review and Meta-analysis.. [DOI: 10.21203/rs.3.rs-3123741/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background Growth hormone deficiency (GHD) is a condition impacting children and adults, leading to low height and other health issues. The primary treatment is daily injections of recombinant human growth hormone (rhGH), though they can be inconvenient and costly. These injections may also negatively impact treatment adherence and outcomes. This study aims to compare the efficacy and safety of once-weekly growth hormone treatment vs daily growth hormone therapy in children with growth hormone insufficiency. Methods To examine the efficacy and safety of once-weekly and once-daily growth hormone treatment for children with growth hormone insufficiency, this meta-analysis followed PRISMA and Cochrane standards. RCTs and prospective cohort studies with children aged 0–18 diagnosed with GHD were considered eligible. We used the risk of bias 2 and the certainty of evidence using the Cochrane tools. Two authors independently assessed papers for eligibility and extracted data after conducting a thorough search of electronic resources. Height velocity, height standard deviation score, insulin-like growth factor 1 levels, and the incidence of adverse events were the primary outcomes. The Revman software version 5.4 was used for data synthesis, and heterogeneity was determined by I-squares greater than 60%. Results This meta-analysis and comprehensive review includes 14 randomized clinical trials and one study was cohort, including 1,322 children with growth hormone insufficiency. Weekly growth hormone treatment at dosages ranging from 0.11 to 0.25 mg enhanced a variety of growth outcomes, including increased height velocity dose (SMD = 0.37, 95% CI, 0.23–0.51; P < 0.001), height standard deviation scores chronological age (SMD= -0.10, 95% CI, -0.13–0.07; P < 0.001), and insulin-like growth factor 1 standard deviation score (SMD = 0.41, 95% CI, 0.40–0.42; P < 0.001). The dosage range of 0.26 to 0.50 mg also improved insulin-like growth factor binding protein-3 significantly (SMD= -0.63, 95% CI, -0.90 – -0.37; P < 0.001). Nevertheless, there were no significant differences in the occurrence of adverse events through the dosage levels (OR = 0.71, 95% CI 0.36 to 1.40; P = 0.32). Conclusions In children with growth hormone deficit, weekly growth hormone treatment, particularly in the 0.11 to 0.25 mg dose range, can function as a viable alternative to daily growth hormone therapy.

Long-acting growth hormone in 2022

After the isolation of pituitary growth hormone (GH) in 1957, this form of GH, always in limited supply, was the only drug available for the treatment of GH deficiency. In 1985, recombinant GH became available, and the modalities of GH therapies changed dramatically as the supply was unlimited. New indications for GH in pediatrics and adult medicine were developed. Treatment was daily. Now in 2021 long-acting GH (LAGH) became available the world over making GH therapy more patient-friendly and even showing slightly greater efficacy than daily GH therapy. We are now entering a new era of LAGH therapy for pediatric and adult use with new formulations of GH, which will predictably be the preferred form of GH therapy for years to come increasing adherence to GH therapy and possibly even efficacy, that is, better growth rate. The continued availability of new safety data will further solidify the use of LAGH in clinical medicine.

Effect of long-acting growth hormone treatment on endogenous growth hormone secretion in prepubertal patients with idiopathic short stature: A preliminary study

Long-acting growth hormone (LAGH) is emerging to be a new preparation for treatment of short stature. We aimed to determine whether 12-month treatment with LAGH in patients with idiopathic short stature has an effect on the nocturnal endogenous growth hormone (GH) secretion and metabolic consequences and efficacy. Participants included 10 GH-naïve prepubertal children with idiopathic short stature (ISS). One patient was withdrawn due to own decline during study. Participants were randomized on a 1:1 ratio to receive either a daily GH (0.37 mg/kg/week) or once-weekly LAGH (0.7 mg/kg/week) over a 12-month period. Nocturnal endogenous GH secretory profiles obtained from 12-h blood samplings at 30-min interval were assessed at baseline and 2 weeks after the completion of GH treatment. Post-treatment changes in height velocity, height standard deviation score (SDS), metabolic parameters, and adverse events were measured. A total of 4 patients received LAGH, and 5 patients received daily GH. Nocturnal endogenous GH secretory profiles, such as mean serum GH concentrations, frequency, amplitude, interpulse interval of spontaneous GH secretory bursts, and mass of GH released per secretory burst were similar at baseline and after 12-month treatment in both groups. The efficacy and safety after LAGH treatment for 12 months were similar to those of daily GH. In conclusions, these findings indicated that LAGH does not suppress endogenous GH secretion, and can be used for treatment of non-GH deficient short stature with similar efficacy and safety compared to daily GH. These may contribute to define and develop treatment and follow-up protocols for LAGH use in ISS patients.

Height outcomes in Korean children with idiopathic short stature receiving growth hormone treatment

Objectives

Growth hormone (GH) therapy's capacity to increase height velocity and height at the end of the study in children with idiopathic short stature (ISS) is controversial. We aimed to investigate the height standard deviation score (SDS) and height velocity of patients with ISS in Korea who received GH treatment.

Methods

We retrospectively reviewed and performed linear mixed model and survival analyses on data from 12 tertiary hospitals in Korea, including subjects diagnosed with ISS from January 2009 to September 2019, treated with GH therapy for more than 6 months, and who were at a pre-pubertal state at the time of diagnosis.

Results

We included 578 children (330 boys and 248 girls). The mean daily dose of GH in this study was 0.051 mg/kg, which was lower than the approved dose in Korea of 0.062 - 0.067 mg/kg. Height SDS was higher in patients who started treatment before the age of 6 years. The probability of reaching the target SDS (-1 SDS) from the beginning of treatment to 2-3 years after its start was higher in children starting treatment before the age of 6 years. The hazard ratio to reach the target SDS (-1 SDS) when using automatic pen or electronic devices was 1.727 times higher than that when using the needle and syringe device.

Conclusion

ISS patients should start GH treatment at an early age, and even lower-than-recommended drug doses may be effective. The selection of automatic pen or electronic device can have a positive effect on reaching the target height SDS.

New insight into the importance of formulation variables on parenteral growth hormone preparations: potential effect on the injection-site pain

Reducing injection-site pain (ISP) in patients with chronic conditions such as growth hormone deficiency is a valuable strategy to improve patient compliance and therapeutic efficiency. Thus understanding different aspects of pain induction following subcutaneous injection of biotherapeutics and identifying the responsible factors are vital. Here we have discussed the effects of formulation's viscosity, concentration, osmolality, buffering agents, pH, and temperature as well as injection volume, dosing frequency, and different excipients on ISP following subcutaneous injection of commercially available recombinant human growth hormone products. Our literature review found limited available data on the effects of different components of parenteral rhGH products on ISP. This may be due to high cost associated with conducting various clinical trials to assess each excipient in the formulation or to determine the complex interactions of different components and its impact on ISP. Recently, conducting molecular dynamics simulation studies before formulation design has been recommended as an alternative and less-expensive approach. On the other hand, the observed inconsistencies in the available data is mainly due to different pain measurement approaches used in each study. Moreover, it is difficult to translate data obtained from animal studies to human subjects. Despite all these limitations, our investigation showed that components of parenteral rhGH products can significantly contribute to ISP. We suggest further investigation is required for development of long acting, buffer-free, preservative-free formulations. Besides, various excipients are currently being investigated for reducing ISP which can be used as alternatives for common buffers, surfactants or preservatives in designing future rhGH formulations.

What do we do now that the long-acting growth hormone is here?

In standard 52-week phase III clinical trials, once weekly lonapegsomatropin, somatrogon and somapacitan have been found to yield non-inferior height velocities and similar safety profiles to daily GH (DGH) in children with pediatric growth hormone deficiency (PGHD). Lonapegsomatropin, a long-acting GH therapy (LAGH), was approved by the United States Food and Drug Administration (FDA) in August 2021 for the treatment of PGHD and has also been approved in other regions of the world. Somatrogon was approved for the treatment of PGHD beginning in some regions beginning in late 2021. Somapacitan was approved by the FDA for the treatment of Adult GHD in August 2020. The phase III clinical trial of somapacitan for the treatment of PGHD has been completed and demonstrated non-inferiority of somapacitan to DGH. New LAGH products may improve patient adherence, quality of life and clinical outcomes, particularly in patients with poor adherence to daily GH injections in the future. With the availability of new LAGH products, clinicians will need to identify the best candidates for LAGH therapy and understand how to monitor and adjust therapy. Long-term surveillance studies are needed to demonstrate adherence, efficacy, cost-effectiveness and safety of LAGH preparations and to understand how the non-physiological pharmacokinetic and pharmacodynamic profiles following administration of each LAGH product relate to short- and long-term safety and efficacy of LAGH therapy.

Effect of Weekly Long-Acting Growth Hormone Replacement Therapy Compared to Daily Growth Hormone on Children With Short Stature: A Meta-Analysis

Background

We performed a meta-analysis to evaluate the efficacy and safety of weekly long-acting growth hormone replacement therapy compared to daily growth hormone in children with short stature.

Methods

A systematic literature search up to April 2021 was performed and 11 studies included 1,232 children with short stature treated with growth hormone replacement therapy at the start of the study; 737 of them were using weekly long-acting growth hormone replacement therapy and 495 were using daily growth hormone. They were reporting relationships between the efficacy and safety of long-acting growth hormone replacement therapy and daily growth hormone in children with short stature. We calculated the odds ratio (OR), and mean difference (MD) with 95% confidence intervals (CIs) to assess the efficacy and safety of weekly long-acting growth hormone replacement therapy compared to daily growth hormone in children with short stature using the dichotomous or continuous method with a random or fixed-effect model.

Results

Long-acting growth hormone replacement therapy had significantly lower height standard deviation scores chronological age (MD, -0.10; 95% CI, -0.13 to -0.08, p <0.001), and insulin-like growth factor binding protein-3 (MD, -0.69; 95% CI, -1.09 to -0.30, p <0.001) compared to daily growth hormone in children with short stature.However, growth hormone replacement therapy had no significantly difference in height velocity (MD, -0.09; 95% CI, -0.69-0.5, p = 0.76), height standard deviation scores bone age (MD, -0.04; 95% CI, -0.10-0.02, p = 0.16), insulin-like growth factor 1 standard deviation scores (MD, 0.26; 95% CI, -0.26-0.79, p = 0.33), and incidence of adverse events (OR, 1.16; 95% CI, 0.90-1.50, p = 0.25) compared to daily growth hormone in children with short stature.

Conclusions

Long-acting growth hormone replacement therapy had significantly lower height standard deviation scores chronological age, and insulin-like growth factor binding protein-3 compared to daily growth hormone in children with short stature. However, growth hormone replacement therapy had no significant difference in height velocity, height standard deviation scores bone age, insulin-like growth factor 1 standard deviation scores, and incidence of adverse events compared to daily growth hormone in children with short stature. Further studies are required to validate these findings.

Usefulness and Potential Pitfalls of Long-Acting Growth Hormone Analogs

Daily recombinant human GH (rhGH) is currently approved for use in children and adults with GH deficiency (GHD) in many countries with relatively few side-effects. Nevertheless, daily injections can be painful and distressing for some patients, often resulting in non-adherence and reduction of treatment outcomes. This has prompted the development of numerous long-acting GH (LAGH) analogs that allow for decreased injection frequency, ranging from weekly, bi-weekly to monthly. These LAGH analogs are attractive as they may theoretically offer increased patient acceptance, tolerability, and therapeutic flexibility. Conversely, there may also be pitfalls to these LAGH analogs, including an unphysiological GH profile and differing molecular structures that pose potential clinical issues in terms of dose initiation, therapeutic monitoring, incidence and duration of side-effects, and long-term safety. Furthermore, fluctuations of peak and trough serum GH and IGF-I levels and variations in therapeutic efficacy may depend on the technology used to prolong GH action. Previous studies of some LAGH analogs have demonstrated non-inferiority compared to daily rhGH in terms of increased growth velocity and improved body composition in children and adults with GHD, respectively, with no significant unanticipated adverse events. Currently, two LAGH analogs are marketed in Asia, one recently approved in the United States, another previously approved but not marketed in Europe, and several others proceeding through various stages of clinical development. Nevertheless, several practical questions still remain, including possible differences in dose initiation between naïve and switch-over patients, methodology of dose adjustment/s, timing of measuring serum IGF-I levels, safety, durability of efficacy and cost-effectiveness. Long-term surveillance of safety and efficacy of LAGH analogs are needed to answer these important questions.

Long-Acting Growth Hormone Preparations - Current Status and Future Considerations

CONTEXT

Long-acting GH (LAGH) preparations are currently being developed in an attempt to improve adherence. The profile of GH action following administration of LAGH raises practical questions about clinical monitoring and long-term safety and efficacy of these new therapeutic agents.

METHODS

Recent literature and meeting proceedings regarding LAGH preparations are reviewed.

RESULTS

Multiple LAGH preparations are currently at various stages of development, allowing for decreased GH injection frequency from daily to weekly, biweekly, or monthly. Following administration of LAGH, the serum peak and trough GH and IGF-I levels vary depending upon the mechanism used to prolong GH action. Randomized, controlled clinical trials of some LAGH preparations have reported non-inferiority compared with daily recombinant human GH (rhGH) for improved growth velocity and body composition in children and adults with GH deficiency (GHD), respectively. No significant LAGH-related adverse events have been reported during short-term therapy.

CONCLUSION

Multiple LAGH preparations are proceeding through clinical development with some showing promising evidence of short-term clinical efficacy and safety in children and adults with GHD. The relationship of transient elevations of GH and IGF-I following administration of LAGH to efficacy and safety remain to be elucidated. For LAGH to replace daily rhGH in the treatment of individuals with GHD, a number of practical questions need to be addressed including methods of dose adjustment, timing of monitoring of IGF-I, safety, efficacy, and cost-effectiveness. Long-term surveillance of efficacy and safety of LAGH preparations will be needed to answer these clinically relevant questions.

Perspectives on long-acting growth hormone therapy in children and adults

Growth hormone therapy with daily injections of recombinant human growth hormone has been available since 1985, and is shown to be safe and effective treatment for short stature in children and for adult growth hormone deficiency. In an effort to produce a product that would improve patient adherence, there has been a strong effort from industry to create a long acting form of growth hormone to ease the burden of use. Technologies used to increase half-life include depot formulations, PEGylated formulations, pro-drug formulations, non-covalent albumin binding growth hormone and growth hormone fusion proteins. At present, two long acting formulations are on the market in China and South Korea, and several more promising agents are under clinical investigation at various stages of development throughout the world. Arch Endocrinol Metab. 2019;63(6):601-7.

Efficacy and safety of long-acting growth hormone in children with short stature: a systematic review and meta-analysis

PURPOSE

Long-acting growth hormone (GH) has been developed to address the noncompliance and decreased efficacy associated with daily GH injections. We aimed to evaluate the efficacy and safety of long-acting GH replacement therapy in children with short stature.

METHODS

Randomized controlled trials (RCTs) that investigated the efficacy and safety of long-acting GH therapy in children with short stature in comparison with daily GH injections were searched in Medline, Embase, and the Cochrane Central Register of Controlled Trials. A random-effect model was used to pool data using mean difference and odds ratios (OR). (PROSPERO registration number: CRD42018111105).

RESULTS

Seven relevant studies were finally included. Meta-analysis found there was no significant difference between high-dose long-acting GH and daily GH in terms of height velocity (HV) (mean difference (MD) = -0.10, 95% CI, -0.79 to 0.60, P = 0.79). Moreover, no significant difference was observed in height standard deviation scores (Ht SDS) between high-dose long-acting GH and daily GH (MD = -0.07, 95% CI, -0.18 to 0.03, P = 0.17). Treatment with high-dose long-acting GH significantly increased IGF-1 SDS when compared with daily GH (MD = 0.31, 95% CI, 0.06-0.56, P = 0.02). In safety assessment, no significant difference was observed in the incidence of adverse events between high-dose long-acting GH and daily GH (OR 1.42, 95% CI, 0.65-3.11, P = 0.38).

CONCLUSIONS

There is no evidence to support differences in the effects of long-acting GH compared with those of daily GH. More RCTs that focus on the safety of high-dose long-acting GH treatment, especially the detection of adverse events caused by elevated levels of serum IGF-1, are needed in the future.