Non-compliance with growth hormone treatment in children is common and impairs linear growth

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

BACKGROUND/AIMS

To determine the optimal dose of LB03002, a sustained-release, once-weekly formulation of recombinant human growth hormone (rhGH), and to compare its efficacy and safety with daily rhGH in children with idiopathic short stature (ISS).

METHODS

This multicenter, randomized, open-label, phase II study included GH-naïve, prepubertal children with ISS, randomized to receive daily rhGH 0.37 mg/kg/week (control, n = 16), LB03002 0.5 mg/kg/week (n = 14), or LB03002 0.7 mg/kg/week (n = 16). The primary endpoint was height velocity (HV) change at week 26.

RESULTS

At week 26, the least square (LS) means for HV change (cm/year) with control, LB03002 0.5 mg/kg/week, and LB03002 0.7 mg/kg/week were 5.08, 3.65, and 4.38, and the LS means for the change in height standard deviation score were 0.65, 0.49, and 0.58, respectively. The lower bound of the 90% confidence interval for the difference between LB03002 0.7 mg/kg/week and the control in the LS mean for HV change (-1.72) satisfied the noninferiority margin (-1.75). Adverse events were generally mild and short-lived.

CONCLUSION

A once-weekly regimen of LB03002 0.7 mg/kg demonstrated noninferiority to the daily regimen of rhGH 0.37 mg/kg/week in terms of HV increments. LB03002 was well tolerated and its safety profile was comparable with that of daily rhGH.

The current state of long-acting growth hormone preparations for growth hormone therapy

PURPOSE OF REVIEW

To discuss the rationale of developing long-acting growth hormone (LAGH) preparations, to describe the technologies designed to prolong GH action, and to address key issues regarding efficacy, safety, and monitoring while on treatment.

REVIEW FINDINGS

Recombinant human GH is currently approved for daily use and has been shown to restore longitudinal growth, and improve body composition with relatively few side-effects in children and adults with GH deficiency, respectively. However, daily injections can be inconvenient, painful and distressing for some patients, resulting in decreased adherence and efficacy. Over a dozen pharmaceutical companies have designed LAGH preparations that are at various stages of development using a number of different methods to prolong GH action.

SUMMARY

LAGH will represent an advancement over daily recombinant human GH injections because of fewer injections that may offer increased acceptance, tolerability, and therapeutic flexibility to patients that potentially can improve treatment outcomes. However, given the unphysiological profile of LAGH preparations, long-term surveillance of efficacy and safety are needed. This review summarizes recent developments of LAGH preparations, and highlights the importance of long-term surveillance registries to assess for efficacy and safety that will be essential for understanding the impact of prolonged exposure to these compounds.

Adherence and long-term growth outcomes: results from the easypod™ connect observational study (ECOS) in paediatric patients with growth disorders

OBJECTIVE

The easypod connect observational study (ECOS) assessed treatment adherence among paediatric patients receiving growth hormone (GH) via the easypod electronic injection device.

DESIGN

ECOS was an open-label, observational, longitudinal study conducted in 24 countries between 2010 and 2016, enrolling children treated with GH.

METHODS

The primary endpoint was the rate of treatment adherence during 5 years of follow-up. Impact of adherence on growth outcomes was assessed using Spearman's product-moment correlations.

RESULTS AND CONCLUSIONS

Overall, 1190 patients had easypod data available for ≥3 months; most patients had GH deficiency (75%); 606 of these patients were GH naïve at baseline. Over the first year of monitoring, the median rate of adherence was 93.7% among patients overall and >93.0% in GH-naïve patients, irrespective of the treatment indication. Clinically meaningful improvements in growth rates were observed after 1 year of treatment across all GH indications. Adherence decreased with increasing treatment duration, but the overall median adherence rate remained high after 3 years of follow-up: 87.2% (n = 409), 75.5% after 4 years (n = 143) and 70.2% after 5 years (n = 43). Statistically significant correlations between adherence and 1-year change in height standard deviation score (P < 0.001 for patients overall) and height velocity (P < 0.001) were observed.

CONCLUSIONS

ECOS produced accurate, real-time adherence data in a large population of GH-treated children over 5 years of follow-up. Using the easypod connect system, physicians can potentially identify patients with inadequate adherence and poor response to treatment, enabling them to take appropriate action to help them maximise the benefits of GH treatment.

A long-acting pegylated recombinant human growth hormone (Jintrolong® ) in healthy adult subjects: Two single-dose trials evaluating safety, tolerability and pharmacokinetics

WHAT IS KNOWN AND OBJECTIVE

Jintrolong^® is a pegylated recombinant human growth hormone (rhGH) (PEG-rhGH) developed for weekly subcutaneous (sc) injection. The current human tolerability trial and pharmacokinetics (PK) trial evaluated the safety, tolerability and PK of single-dose Jintrolong^® injection in healthy adult subjects.

METHODS

Both trials were single-centre, randomized, open-label and single-dose studies. In the human tolerability trial, 34 healthy subjects were randomized to receive single-dose Jintrolong^® sc injection (0.01, 0.06, 0.2, 0.5 or 0.8 mg/kg) or placebo. In the PK study, 30 healthy male subjects were evenly randomized into 3 groups to receive single-dose Jintrolong^® sc injection (0.1, 0.2 or 0.4 mg/kg), and the subjects receiving 0.4 mg/kg Jintrolong^® were given a single sc injection of conventional rhGH (0.067 mg/kg) after a 14-day washout period. Safety and PK profiles of Jintrolong^® were evaluated.

RESULTS AND DISCUSSION

Jintrolong^® was well tolerated with no serious adverse events or local injection responses. The PK trial showed that the plasma growth hormone concentration elevated quickly and stayed at peak level between 12 and 48 hours post-Jintrolong^® injection, then decreased gradually back to baseline within 168 hours. Compared to single-dose conventional rhGH, Jintrolong^® at all doses demonstrated significantly longer half time and time to maximum plasma concentration, lower clearance and higher systemic drug exposure, indicating prolonged presence of GH in the subjects' circulation. Additionally, systemic exposure to Jintrolong^® increased in a dose-dependent manner.

WHAT IS NEW AND CONCLUSION

Single-dose Jintrolong^® injection was well tolerated in healthy adult subjects, and the maximum tolerable dose was no lower than 0.8 mg/kg. Jintrolong^® was long-acting with the potential for weekly administration.

Adherence to somatotropin treatment administered with an electronic device

INTRODUCTION

Adherence to somatotropin treatment is associated with increased growth velocity and improved adult height. The purpose of this study is to determine the adherence of patients undergoing treatment with an electronic device and its relationship with different variables (age, gender, duration of treatment, diagnosis, height, and growth rate).

MATERIAL AND METHODS

Descriptive, longitudinal and retrospective study of children less than 14 years of age undergoing treatment with somatotropin administered with the Easypod® electronic device in the Paediatric Endocrinology Outpatient Clinic of the General University Hospital of Ciudad Real, Spain. Adherence was monitored for 12 months and was defined according to the equation: (days administered at the prescribed dose / prescribed days)×100. The data analysis was performed using SPSS software.

RESULTS

Data were collected from 30 patients, with a predominance of males (57%), a mean age of 6.09 years, with 51% of children less than 5 years old. The most common reasons for the treatment were: small for gestational age (55%) and growth hormone deficiency (38%). The mean duration of treatment was 4.3 years (3.6-5). A mean adherence of 92.3% (87.7-96.9) was observed, and there was a significant correlation with age (Pearson R = -0.384, P=.03), and duration of treatment (Pearson R = -0.537; P=.003).

CONCLUSIONS

The adherence in our patients with electronic device is high (92.3%), and is inversely associated with age and duration. The use of electronic devices allows monitoring of therapeutic compliance, which affects the optimisation of treatment.

Design of the long-term observational cohort study with recombinant human growth hormone in Korean children: LG Growth Study

PURPOSE

Regarding recombinant human growth hormone (rhGH) use in the pediatric population, no long-term follow-up data are available for Korean patients. To fill in the gap of knowledge, a registry study (LG Growth Study) was initiated to assess the safety and effectiveness of four types of rhGH products in real-life settings.

METHODS

A total of 4,000 children will be registered and prospectively followed up at 6-month intervals until 2 years after epiphyseal closure to collect data on treatment and adverse events, with primary interest in malignancies and growth outcomes.

RESULTS

As of 22 March 2017, approximately 50% (2,024) of the target number of patients have been included in the analysis set: growth hormone deficiency, 1,297 (64.1%); idiopathic short stature, 315 (15.6%); small for gestational age, 206 (10.2%); Turner syndrome, 197 (9.7%); and chronic renal failure, 9 (0.4%). At baseline, median age (years) was 8 (interquartile range [IQR], 5-11); 52% (1,048) were boys; and the majority were at Tanner stage I (83% based on breast/external genitalia, 97% on pubic hair). Median height standard deviation score was -2.26 (IQR, -2.69 to -2.0), and median bone age delay (years) was -1.46 (IQR, -2.26 to -0.78).

CONCLUSIONS

This registry study will provide the opportunity to assess the risk of malignancies as well as the general safety data in Korean pediatric patients receiving rhGH. In addition, the long-term effectiveness of rhGH and comparative data between different disease entities will provide practical insight on the standard rhGH treatment.

Challenges and future for the delivery of growth hormone therapy

Growth hormone (GH) has multiple roles in sustaining human development and homeostasis. Its pulsatile secretion stimulates growth and contributes to an equilibrium in a process tightly regulated and coordinated by many organs. GH deficiency is a medical condition affecting all ages, with not only significant consequences in the health of the patient but also impact on the quality of life. This review gathers the different strategies used today with a glance at future technologies to treat GH deficiency. We present key aspects for consideration when developing new methods to deliver GH, mimicking or replacing its pulsatile activity. Today and in the future, the fusion of biochemistry, biology and nanotechnology will provide hybrid devices using microfluidic systems. But, until new technologies for GH delivery will become available, current methods must be reinforced in conjunction with the development of better communication strategies between the health system and patients. Treating GH deficiency represents a multidisciplinary effort for which this review provides a glance at potential future directions for this therapy.

Adherence to growth hormone therapy in children and its potential barriers

BACKGROUND

One of the main concerns in chronic diseases such as growth hormone (GH) deficiency is adherence to the treatment, which significantly affects treatment outcomes.

METHODS

This cross-sectional study was conducted among 169 GH recipient children (2-12 years) and teens (13-19 years) referred to a GH distributing teaching pharmacy. The eight-item Morisky Medication Adherence Scale (MMAS) and auto-compliance method were used for the assessment of patients' adherence to GH. The potential barriers to GH therapy adherence and medication persistence were also explored.

RESULTS

Based on the MMAS method, 56.7% of the children and 57.9% of the adolescent groups were adherent to GH therapy. Conversely, according to the auto-compliance method almost all the patients were adherent in the children (95.2%) and adolescent (95.5%) groups. Forgetting to take the injection or refill the prescription, being away from home, exhaustion from long-term injection, drug shortage and inaccessibility to the pharmacy were barriers found to be significantly associated with a low adherence in the children group. While in the adolescent group, forgetting to take the injection, painful injection, concern about long-term complications and exhaustion from long-term injection revealed a significant association with low adherence. Persistence with GH therapy was reported in 75.3% and 67% of children and adolescent patients, respectively.

CONCLUSIONS

The current study revealed that overall adherence of the study population is low. Considering the barriers with significant association with adherence, different strategies can be incorporated to enhance adherence to GH therapy, i.e. providing early patient and parent education and support, medication reminder systems and longer duration of GH prescriptions.

Categorizing factors of adherence to parenteral treatment in growth hormone deficiencies and hemophilia: What should be the targets for future research?

Adherence to treatment regimens in growth hormone dysregulations and hemophilia is related to better outcome and fewer complications over time. Subcutaneous growth hormone injection and intravenous blood factor replacement therapies are parenteral treatments with a comparable regimen calling for similar behavioral processes. Although we have lists of possible factors influencing adherence in these conditions, the evidence is scattered. The objective of this study was to systematically review empirical studies linking factors of adherence with measures of adherence. To categorize the factors, we used a taxonomy from the diabetes literature. We used four major electronic databases to identify articles. We synthesized 27 articles dated 2011-2017 corresponding to inclusion criteria. Results showed a consistent proportion of 20%-25% participants with adherent issues. Strong arguments pointed to the transition to self-care in pediatrics as a vulnerability period (7/27 reports). We found the domains of individual factors (<30% reports), relational factors (<13%), health care (<30%), to be understudied in comparison with that of demographic or clinical context (>74%), and practical issues (>37%). The results suggest that future research should focus on modifiable factors of adherence, with appropriate measurement and intervention strategies. One central methodological limitation of reviewed reports was the lack of longitudinal designs, and the quasi absence of behavioral trial targeting modifiable factors of adherence. A new research agenda should be set in these rare diseases as higher adherence should translate into improved outcome and better quality of life for patients and their families.

Shared Decision-Making in Growth Hormone Therapy-Implications for Patient Care

Several studies have shown that adherence to growth hormone therapy (GHT) is not optimal. There are several reasons why patients may not fully adhere to their treatment regimen and this may have implications on treatment success, patient outcomes and healthcare spending and resourcing. A change in healthcare practices, from a physician paternalistic to a more patient autonomous approach to healthcare, has encouraged a greater onus on a shared decision-making (SDM) process whereby patients are actively encouraged to participate in their own healthcare decisions. There is growing evidence to suggest that SDM may facilitate patient adherence to GHT. Improved adherence to therapy in this way may consequently positively impact treatment outcomes for patients. Whilst SDM is widely regarded as a healthcare imperative, there is little guidance on how it should be best implemented. Despite this, there are many opportunities for the implementation of SDM during the treatment journey of a patient with a GH-related disorder. Barriers to the successful practice of SDM within the clinic may include poor patient education surrounding their condition and treatment options, limited healthcare professional time, lack of support from clinics to use SDM, and healthcare resourcing restrictions. Here we discuss the opportunities for the implementation of SDM and the barriers that challenge its effective use within the clinic. We also review some of the potential solutions to overcome these challenges that may prove key to effective patient participation in treatment decisions. Encouraging a sense of empowerment for patients will ultimately enhance treatment adherence and improve clinical outcomes in GHT.

The rationale and design of TransCon Growth Hormone for the treatment of growth hormone deficiency

The fundamental challenge of developing a long-acting growth hormone (LAGH) is to create a more convenient growth hormone (GH) dosing profile while retaining the excellent safety, efficacy and tolerability of daily GH. With GH receptors on virtually all cells, replacement therapy should achieve the same tissue distribution and effects of daily (and endogenous) GH while maintaining levels of GH and resulting IGF-1 within the physiologic range. To date, only two LAGHs have gained the approval of either the Food and Drug Administration (FDA) or the European Medicines Agency (EMA); both released unmodified GH, thus presumably replicating distribution and pharmacological actions of daily GH. Other technologies have been applied to create LAGHs, including modifying GH (for example, protein enlargement or albumin binding) such that the resulting analogues possess a longer half-life. Based on these approaches, nearly 20 LAGHs have reached various stages of clinical development. Although most have failed, lessons learned have guided the development of a novel LAGH. TransCon GH is a LAGH prodrug in which GH is transiently bound to an inert methoxy polyethylene glycol (mPEG) carrier. It was designed to achieve the same safety, efficacy and tolerability as daily GH but with more convenient weekly dosing. In phase 2 trials of children and adults with growth hormone deficiency (GHD), similar safety, efficacy and tolerability to daily GH was shown as well as GH and IGF-1 levels within the physiologic range. These promising results support further development of TransCon GH.

Somapacitan, a once-weekly reversible albumin-binding GH derivative, in children with GH deficiency: A randomized dose-escalation trial

OBJECTIVE

To evaluate the safety, local tolerability, pharmacodynamics and pharmacokinetics of escalating single doses of once-weekly somapacitan, a reversible, albumin-binding GH derivative, vs once-daily GH in children with GH deficiency (GHD).

DESIGN

Phase 1, randomized, open-label, active-controlled, dose-escalation trial (NCT01973244).

PATIENTS

Thirty-two prepubertal GH-treated children with GHD were sequentially randomized 3:1 within each of four cohorts to a single dose of somapacitan (0.02, 0.04, 0.08 and 0.16 mg/kg; n=6 each), or once-daily Norditropin^® SimpleXx^® (0.03 mg/kg; n=2 each) for 7 days.

MEASUREMENTS

Pharmacokinetic and pharmacodynamic profiles were assessed.

RESULTS

Adverse events were all mild, and there were no apparent treatment-dependent patterns in type or frequency. Four mild transient injection site reactions were reported in three of 24 children treated with somapacitan. No antisomapacitan/anti-human growth hormone (hGH) antibodies were detected. Mean serum concentrations of somapacitan increased in a dose-dependent but nonlinear manner: maximum concentration ranged from 21.8 ng/mL (0.02 mg/kg dose) to 458.4 ng/mL (0.16 mg/kg dose). IGF-I and IGFBP-3, and change from baseline in IGF-I standard deviation score (SDS) and IGFBP-3 SDS, increased dose dependently; greatest changes in SDS values were seen for 0.16 mg/kg. IGF-I SDS values were between -2 and +2 SDS, except for peak IGF-I SDS with 0.08 mg/kg somapacitan. Postdosing, IGF-I SDS remained above baseline levels for at least 1 week.

CONCLUSIONS

Single doses of once-weekly somapacitan (0.02-0.16 mg/kg) were well tolerated in children with GHD, with IGF-I profiles supporting a once-weekly treatment profile. No clinically significant safety/tolerability signals or immunogenicity concerns were identified.

The response to growth hormone treatment in prepubertal children with growth hormone deficiency in Japan: Comparing three consecutive years of treatment data of The Foundation for Growth Science in Japan between the 1990s and 2000s

Growth hormone (GH) treatment for children with GH deficiency (GHD) is effective in improving adult height. To achieve favorable effects, GH treatment before puberty is very important, because prepubertal height gain is highly correlated with total height gain. However, no report has studied the effects by analyzing a nationwide data from recent GHD patients in Japan. We investigated the response to GH treatment using data compiled in the Foundation for Growth Science in Japan, and compared the effects between the 1990s and 2000s using analysis of covariance. We analyzed 534 prepubertal GHD subjects treated in the 2000s with three consecutive years of data from the start and investigated predictive factors for the effects. The cumulative height standard deviation score (SDS) change over three years of GH treatment was 0.91 ± 0.57 and 1.20 ± 0.62 in the 1990s and 2000s, respectively. Subjects in the 2000s were divided into three groups by severity, and the cumulative height SDS was 1.60 ± 0.93, 1.20 ± 0.54, and 1.00 ± 0.40 indicating severe, moderate, and mild GHD, respectively. Age and height SDS at the start and severity were identified as independent predictive factors. We also found a significant difference in the effects between the two cohorts after adjusting for the different factors (regression coefficient: -0.069, 95% confidence interval: -0.11 to -0.030, p = 0.0006), which might be due to the GH dose effect. We conclude that the effects of GH treatment in the 2000s had improved compared with those in the 1990s.

Nonclinical pharmacokinetic and pharmacodynamic characterisation of somapacitan: A reversible non-covalent albumin-binding growth hormone

OBJECTIVE

Somapacitan is an albumin-binding growth hormone derivative intended for once weekly administration, currently in clinical development for treatment of adult as well as juvenile GH deficiency. Nonclinical in vivo pharmacological characterisation of somapacitan was performed to support the clinical trials. Here we present the pharmacokinetic and pharmacodynamic effects of somapacitan in rats, minipigs, and cynomolgus monkeys.

METHODS

Pharmacokinetic studies investigating exposure, absorption, clearance, and bioavailability after single intravenous (i.v.) and subcutaneous (s.c.) administration were performed in all species. A dose-response study with five dose levels and a multiple dose pharmacodynamic study with four once weekly doses was performed in hypophysectomised rats to evaluate the effect of somapacitan on growth and IGF-I production.

RESULTS

Pharmacokinetic profiles indicated first order absorption from the subcutaneous tissue after s.c. injections for somapacitan in all three species. Apparent terminal half-lives were 5-6h in rats, 10-12h in minipigs, and 17-20h in monkeys. Somapacitan induced a dose-dependent growth in hypophysectomised rats (p<0.001) and an increase in plasma IGF-I levels in rats (p<0.01), minipigs (p<0.01), and cynomolgus monkeys (p<0.05) after single dose administration. Multiple once weekly dosing of somapacitan in hypophysectomised rats induced a step-wise increase in body weight with an initial linear phase the first 3-4days in each dosing interval (p<0.001).

CONCLUSION

The nonclinical pharmacokinetic and pharmacodynamic studies of somapacitan showed similar pharmacokinetic properties, with no absorption-limited elimination, increased clearance and increased and sustained levels of IGF-I in plasma for up to 10days after a single dose administration in all three species. Somapacitan induced a dose-dependent increase in body weight and IGF-I levels in hypophysectomised rats. Multiple dosing of somapacitan in hypophysectomised rats suggested a linear growth for the first 3-4days in each weekly dosing interval, whereas daily hGH dosing showed linear growth for approximately two weeks before reaching a plateau level.

More Favorable Metabolic Impact of Three-Times-Weekly versus Daily Growth Hormone Treatment in Naïve GH-Deficient Children

OBJECTIVE

To evaluate whether two different regimens of weekly injections could lead to similar auxological and metabolic effects in children with growth hormone deficiency (GHD).

DESIGN

32 GHD children (25 males, mean age 10.5 ± 2.2 yr) were randomly assigned to receive daily (group A, 16 patients) or TIW (group B, 16 patients) GHT for 12 months.

METHODS

Auxological parameters, insulin-like growth factor-I (IGF-I), glucose and insulin during OGTT, glycosylated hemoglobin (HbA1c), lipid profile, the oral disposition index (DIo), the homeostasis model assessment estimate of insulin resistance (Homa-IR), and the insulin sensitivity index (ISI).

RESULTS

After 12 months, both groups showed a significant and comparable improvement in height (p < 0.001) and IGF-I (p < 0.001). As regards the metabolic parameters, in both groups, we found a significant increase in fasting insulin (p < 0.001 and p = 0.026) and Homa-IR (p < 0.001 and p = 0.019). A significant increase in fasting glucose (p = 0.001) and a decrease in ISI (p < 0.001) and DIo (p = 0.002) were only found in group A.

CONCLUSIONS

The TIW regimen is effective and comparable with the daily regimen in improving auxological parameters and has a more favorable metabolic impact in GHD children. This trial is registered with ClinicalTrials.gov NCT03033121.

A Randomized Phase 2 Study of Long-Acting TransCon GH vs Daily GH in Childhood GH Deficiency

CONTEXT

TransCon Growth Hormone (GH) (Ascendis Pharma) is a long-acting recombinant sustained-release human GH prodrug in development for children with GH deficiency (GHD).

OBJECTIVE

To compare the pharmacokinetics, pharmacodynamics, safety, and efficacy of weekly TransCon GH to that of daily GH in prepubertal children with GHD.

DESIGN

Randomized, open-label, active-controlled study of three doses of weekly TransCon GH versus daily Genotropin (Pfizer).

SETTING

Thirty-eight centers in 14 European countries and Egypt.

PATIENTS

Prepubertal male and female treatment-naïve children with GHD (n = 53).

INTERVENTIONS

Subjects received one of three TransCon GH doses (0.14, 0.21, or 0.30 mg GH/kg/wk) or Genotropin 0.03 mg GH/kg/d for 26 weeks.

MAIN OUTCOME MEASURES

GH and insulinlike growth factor-1 (IGF-1) levels, growth, adverse events, and immunogenicity.

RESULTS

Both GH maximum concentration and area under the curve were similar following TransCon GH or Genotropin administration at comparable doses. A dose response was observed, with IGF-1 standard deviation scores increasing into the normal range for all three TransCon GH doses. Annualized mean height velocity for the three TransCon GH doses ranged from 11.9 cm to 13.9 cm, which was not statistically different from 11.6 cm for Genotropin. Adverse events were mild to moderate, and most were unrelated to the study drug. Injection site tolerance was good. One TransCon GH subject developed a low-titer, nonneutralizing antibody response to GH.

CONCLUSIONS

The results suggest that long-acting TransCon GH is comparable to daily Genotropin for GH (pharmacokinetics) and IGF-1 (pharmacodynamics) levels, safety, and efficacy and support advancement into phase 3 development.

Long-Acting C-Terminal Peptide-Modified hGH (MOD-4023): Results of a Safety and Dose-Finding Study in GHD Children

CONTEXT

Daily injections are required for growth hormone (GH) replacement therapy, which may cause low compliance as a result of inconvenience and distress in patients.

OBJECTIVE

C-terminal peptide-modified human GH (MOD-4023) is developed for once-a-week dosing regimen in GH-deficient (GHD) adults and children. The present trial was a safety and dose-finding study for weekly MOD-4023 in GHD children.

DESIGN

A multicenter, open-label, randomized, controlled phase 2 study in children with GHD, evaluating the safety, tolerability, pharmacokinetics/pharmacodynamics, and efficacy of three different weekly MOD-4023 doses, compared with daily recombinant human GH (r-hGH).

SETTING

The trial was conducted in 14 endocrinology centers in Europe.

PATIENTS

Fifty-three prepubertal children with GHD completed 12 months of treatment with either MOD-4023 (N = 42) or r-hGH (N = 11).

INTERVENTIONS

C-terminal peptide-modified hGH (MOD-4023) was administered weekly at a dose of either 0.25, 0.48, or 0.66 mg/kg/wk and compared with daily hGH at a dose of 0.24 mg/kg/wk.

RESULTS

MOD-4023 showed an estimated half-life approximately fivefold to 10-fold longer when compared with daily r-hGH. Insulin-like growth factor (IGF)-I and IGF-binding peptide 3 showed a dose-dependent increase during MOD-4023 treatment. IGF-I standard deviation score for MOD-4023 did not exceed +2. All MOD-4023 cohorts demonstrated adequate catch-up growth. The 0.66 mg/kg/wk dose demonstrated efficacy closest to daily r-hGH. No serious adverse events were observed during MOD-4023 treatment, and its tolerability was consistent with known properties of r-hGH.

CONCLUSIONS

This study confirms the long-acting properties of MOD-4023 and shows a promising safety and tolerability profile. This provides support for initiation of a phase 3 study in GHD children using a single weekly injection of MOD-4023.

Growth Hormone Utilization Review in a Pediatric Primary Care Setting

Objective:

One of the main problems facing public health providers and administrators in many countries is ensuring the rational use of high-cost drugs. In this regard, on-going process of medication use evaluation can be considered as a useful tool. In this study, we evaluated certain usage aspects of a highly-cost medication, that is, recombinant growth hormone (GH).

Methods:

This cross-sectional study conducted from August 2012 to August 2014. Children receiving GH ± gonadotropin releasing hormone (GnRH) analogs were included in the study. A researcher-designed checklist was developed to evaluate the GH utilization in these patients. Baseline demographic characteristics and background clinical and growth data, as well as any aspects of drug therapy including indications, dosing, monitoring, and discontinuation were collected from the patients' medical records.

Findings:

Seventy children receiving GH entered the study, of which 23 patients (32.85%) received GH and GnRH analogs simultaneously. At the baseline, 67 children (95.7%) had GH stimulation test, whereas serum insulin-like growth factor-1 (IGF-1) levels were measured in 63 (90%) patients. Sixty-seven patients (95.71%) had thyroid function test, whereas bone age was determined in 68 children (97.14%). The mean ± standard deviation of GH dose for idiopathic short stature, GH deficiency, Turner's syndrome and born small for gestational age in our study was 0.22 ± 0.025 mg/kg/week, 0.23 ± 0.04 mg/kg/week, 0.22 ± 0.015 mg/kg/week, and 0.23 ± 0.02 mg/kg/week, respectively. Height and weight of all patients were followed every 3–6 months, regularly. Thirty patients were treated with GH for at least 1 year, of which thyroid hormones and IGF-1 levels were measured annually in 25 (83.33%) and 26 (86.66%) patients, respectively; while bone age was evaluated in 13 (43.33%) children, annually. GH treatment was discontinued in 15 patients (21.42%), while financial problem was the major reason.

Conclusion:

Diagnostic tests and monitoring of height, weight, IGF-1 level and thyroid function was properly performed in this setting. However, a number of patients with ISS and Turner's syndrome were under-dosed.

MOD-4023, a long-acting carboxy-terminal peptide-modified human growth hormone: results of a Phase 2 study in growth hormone-deficient adults

OBJECTIVE

Growth hormone (GH) replacement therapy currently requires daily injections, which may cause distress and low compliance. C-terminal peptide (CTP)-modified growth hormone (MOD-4023) is being developed as a once-weekly dosing regimen in patients with GH deficiency (GHD). This study's objective is to evaluate the safety, pharmacokinetics (PK), pharmacodynamics (PD) and efficacy of MOD-4023 administered once-weekly in GHD adults.

DESIGN

54 adults with GHD currently treated with daily GH were normalized and randomized into 4 weekly dosing cohorts of MOD-4023 at 18.5%, 37%, 55.5% or 123.4% of individual cumulative weekly molar hGH dose. The study included 2 stages: Stage A assessed the effectiveness and PK/PD profiles of the 4 dosing regimens of MOD-4023. Stage B was an extension period of once-weekly MOD-4023 administration (61.7% molar hGH content) to collect further safety data and confirm the results from Stage A.

RESULTS

Dose-dependent response was observed for both PK and PD data of weekly MOD-4023 treatment. Insulin-like growth factor I (IGF-I) SDS levels were maintained within normal range. The 18.5% cohort was discontinued due to low efficacy. MOD-4023 was well tolerated and exhibited favorable safety profile in all dose cohorts. The reported adverse events were consistent with known GH-related side effects.

CONCLUSIONS

Once-weekly MOD-4023 administration in GHD adults was found to be clinically effective while maintaining a favorable safety profile and may obviate the need for daily injections. Weekly GH injections may improve compliance and overall outcome. The promising results achieved in this Phase 2 study led to a pivotal Phase 3 trial, which is currently ongoing.

Optimizing Patient Management and Adherence for Children Receiving Growth Hormone

Poor adherence with growth hormone (GH) therapy has been associated with worse clinical outcomes, which in children relates specifically to their linear growth and loss of quality of life. The "360° GH in Europe" meeting, held in Lisbon, Portugal, in June 2016 and funded by Merck KGaA (Germany), examined many aspects of GH diseases. The three sessions, entitled "Short Stature Diagnosis and Referral," "Optimizing Patient Management," and "Managing Transition," each benefited from three guest speaker presentations, followed by an open discussion and are reported as a manuscript, authored by the speakers. Reported here is a summary of the proceedings of the second session, which reviewed the determinants of GH therapy response, factors affecting GH therapy adherence and the development of innovative technologies to improve GH treatment in children. Response to GH therapy varies widely, particularly in regard to the underlying diagnosis, although there is little consensus on the definition of a poor response. If the growth response is seen to be less than expected, the possible reasons should be discussed with patients and their parents, including compliance with the therapy regimen. Understanding and addressing the multiple factors that influence adherence, in order to optimize GH therapy, requires a multi-disciplinary approach. Because therapy continues over many years, various healthcare professionals will be involved at different periods of the patient's journey. The role of the injection device for GH therapy, frequent monitoring of response, and patient support are all important for maintaining adherence. New injection devices are incorporating electronic technologies for automated monitoring and recording of clinically relevant information on injections. Study results are indicating that such devices can at least maintain GH adherence; however, acceptance of novel devices needs to be assessed and there remains an on-going need for innovations.

A Critical Appraisal of Growth Hormone Therapy in Growth Hormone Deficiency and Turner Syndrome Patients in Turkey

Early detection of abnormal growth, identification of the underlying cause, and appropriate treatment of the medical condition is an important issue for children with short stature. Growth hormone (GH) therapy is widely used in GH-deficient children and also in non-GH-deficient short stature cases who have findings conforming to certain indications. Efficacy of GH therapy has been shown in a multitude of short- and long-term studies. Age at onset of GH therapy is the most important factor for a successful treatment outcome. Optimal dosing is also essential. The aim of this review was to focus on challenges in the early diagnosis and appropriate management of short stature due to GH deficiency (GHD) and Turner syndrome. These are the most frequent two indications for GH therapy in Turkey approved by the Ministry of Health for coverage by the national insurance system.

Adherence in children with growth hormone deficiency treated with r-hGH and the easypod™ device

PURPOSE

Poor adherence to recombinant human growth hormone (r-hGH) therapy is associated with reduced growth velocity in children with growth hormone deficiency (GHD). This twelve-month observational study was to assess adherence in r-hGH patients treated with the easypod^™, an electronic, fully automated injection device designed to track the time, date and dose administered.

METHODS

Ninety-seven prepubertal patients receiving r-hGH therapy were included in the study from ten Italian clinical sites and 88 completed the study. To avoid possible confounding effects, only GHD patients (79/88; 89.7 % of the overall study population) were considered in the final analysis. The primary endpoint-adherence to treatment-was calculated as the proportion of injections correctly administered during the observational period out of the expected total number of injections. The relevant information, tracked by the easypod^™, was collected at months 6 (V1) and 12 (V2) after baseline (V0). At study termination, adherence data were partially available from 16 patients and fully available from 53 patients. As secondary endpoints, serum IGF-1 levels, fasting serum glucose and insulin levels and key anthropometric characteristics (height, waist circumference and BMI) were also determined.

RESULTS

The easypod^™ data showed that 56.7 % of the patients were considered to be fully (≥92 %) adherent to their treatment throughout the period V0-V2. Treatment improved stature, significantly increased IGF-1 and produced a non-significant increase in blood glucose and insulin levels.

CONCLUSIONS

The injection-recording system and other characteristics of easypod^™ could enhance the ability of physicians to monitor adherence to r-hGH treatment.

Low Treatment Adherence in Pubertal Children Treated with Thyroxin or Growth Hormone

BACKGROUND

Treatment outcome depends largely on treatment adherence (TA). However, studies analyzing TA in chronic endocrine diseases are scarce and controversial in childhood.

PATIENTS AND METHODS

We studied TA in 103 children treated subcutaneously with growth hormone (GH) and 97 children treated orally with thyroxin. TA was calculated based on the prescription refill rates. The number of GH injections was recorded by an autoinjector device in 23 children treated with GH.

RESULTS

The correlation between recorded TA and calculated TA based on prescription refill rates was very good (p < 0.001, r = 0.83). TA was lower (p < 0.01) in pubertal children compared to prepubertal children and in children self-administering their medication compared to those whose drug was administered by their parents, both in GH- and thyroxin-treated children. Overall, 67% of the pubertal children treated with GH and 58% of the pubertal children treated with thyroxin missed at least 1 dose per week. TA was higher (p < 0.001) in children with thyroxin treatment compared to children treated with recombinant human GH (8 vs. 26% missed >3 doses/week).

DISCUSSION

Puberty and self-administration of drugs were negative predictors of TA. Therefore, in puberty, prevention and treatment efforts should be undertaken to improve TA, especially when adolescents administer their drugs themselves.

Diagnosis and management of growth disorders in Gulf Cooperation Council (GCC) countries: Current procedures and key recommendations for best practice

Diagnosis and management of growth disorders comprises an important area of pediatric practice. Current procedures in the different stages of the identification, referral, investigation, and treatment of growth disorders in the Gulf Cooperation Council (GCC) countries have been summarized. Evidence-based procedures, relating specifically to height screening for identification of short stature, auxological criteria for patient referral from primary to secondary pediatric care, and general and endocrine investigations and diagnosis have been discussed and outlined. The management issues related to key disorders that are licensed for growth hormone (hGH) therapy, namely GH deficiency, Turner syndrome, short stature related to birth size small for gestational age (SGA), and idiopathic short stature are discussed with recommendations described for best practice. Finally, two key components of short stature management, namely transitional care for the transfer of patients from pediatric to adult endocrinology services and adherence to recommended therapy with hGH, have been addressed with current practice outlines and recommendations presented.

Adherence to growth hormone therapy: results of a multicenter study

OBJECTIVE

To evaluate the adherence to growth hormone (GH) therapy and identify the influencing factors and outcomes in children.

METHODS

A total of 217 GH-naïve patients in 6 pediatric endocrinology clinics were enrolled in the study. Structured questionnaires were filled out and patients were evaluated at the initiation and 3rd, 6th, and 12th months of therapy. Patients were categorized into 4 adherence segments based on percentage of doses omitted at each evaluation period, classified as excellent if 0%, good if 5%, fair if 5 to 10%, and poor if > 10%.

RESULTS

There was a decrement in adherence to GH therapy during the study period (P = .006). Patients who showed excellent and good adherence to therapy had better growth velocity and growth velocity standard deviation scores (SDSs) (P = .014 and P = .015, respectively). A negative correlation between growth velocity SDS and number of missed injections was also observed (r = -.412; P = .007). A positive correlation between delta insulin-like growth factor-1 (IGF-1) SDS and growth velocity was demonstrated (r = .239; P = .042). IGF-1 levels were significantly higher in patients who showed excellent and good adherence to therapy (P = .01). Adherence was better in boys than in girls (P = .035), but adherence rates were not associated with age, cause of GH treatment, socioeconomic status, person who administered the injections, type of injection device, or GH product.

CONCLUSION

Poor adherence to GH therapy was common in our group of patients and was one of the factors underlying suboptimal growth during therapy. Before considering other problems that can affect growth, clinicians should confirm good adherence to therapy.

Early cessation and non-response are important and possibly related problems in growth hormone therapy: An OZGROW analysis

OBJECTIVE

To investigate growth hormone (GH) treatment and treatment cessation with respect to efficacy and efficiency. To identify factors that best classify or predict cessation type: completed treatment (CT), early cessation (EC), or non-response (NR).

DESIGN

Observational study (1990-2013) of the Australian GH Program comparing CT, EC, and NR groups with respect to demographic, clinical, and response criteria. All patients treated for GH deficiency (GHD; 909), short stature and slow growth (SSSG; 2144), and Turner Syndrome (TS; 626) were included. Information was retrieved from the OZGROW database.

RESULTS

51.9% of patients were EC, 40.7% CT and 7.4% NR.Median treatment durations for NR patients were often longer than patients who completed treatment. EC and NR groups were both associated with poor growth response with males overrepresented.Socioeconomic status differentiated NR (higher) and EC (lower) groups.

CONCLUSIONS

EC was observed at very high rates and appears, generally, to be a little-recognised but frequent problem in GH therapy.EC and delayed recognition of NR may be interrelated being differentiated by the decision to cease or continue treatment following poor response.Poor treatment compliance is likely a major causal factor in EC.Strategies to address poor response and compliance have been developed, however, given the scale of these problems, it may be that long acting GH formulations or individualized treatment need consideration.

Growth Hormone Research Society perspective on the development of long-acting growth hormone preparations

OBJECTIVE

The Growth Hormone (GH) Research Society (GRS) convened a workshop to address important issues regarding trial design, efficacy, and safety of long-acting growth hormone preparations (LAGH).

PARTICIPANTS

A closed meeting of 55 international scientists with expertise in GH, including pediatric and adult endocrinologists, basic scientists, regulatory scientists, and participants from the pharmaceutical industry.

EVIDENCE

Current literature was reviewed for gaps in knowledge. Expert opinion was used to suggest studies required to address potential safety and efficacy issues.

CONSENSUS PROCESS

Following plenary presentations summarizing the literature, breakout groups discussed questions framed by the planning committee. Attendees reconvened after each breakout session to share group reports. A writing team compiled the breakout session reports into a draft document that was discussed and revised in an open forum on the concluding day. This was edited further and then circulated to attendees from academic institutions for review after the meeting. Participants from pharmaceutical companies did not participate in the planning, writing, or in the discussions and text revision on the final day of the workshop. Scientists from industry and regulatory agencies reviewed the manuscript to identify any factual errors.

CONCLUSIONS

LAGH compounds may represent an advance over daily GH injections because of increased convenience and differing phamacodynamic properties, providing the potential for improved adherence and outcomes. Better methods to assess adherence must be developed and validated. Long-term surveillance registries that include assessment of efficacy, cost-benefit, disease burden, quality of life, and safety are essential for understanding the impact of sustained exposure to LAGH preparations.

Stories of experiences of care for growth hormone deficiency: the CRESCERE project

AIMS

Growth hormone deficiency therapy is demanding for patients and caregivers. Teams engaged in the clinical management of growth hormone deficiency therapy need to know how families live with this condition, to provide an adequate support and prevent the risk of withdrawal from therapy.

METHODS

Using Narrative Medicine, testimonies from patients, their parents and providers of care were collected from 11 Italian centers. Narrations were analyzed throughout an elaboration of recurring words and expressions.

RESULTS

Although care management and outcomes were considered satisfying in the 182 collected narratives, recurring signals of intolerance among adolescents and the worry of not being well informed about side effects among parents are open issues.

CONCLUSION

Narratives found that communication issues could decrease adherence and influence the physicians' clinical practice.

Variability in adherence to rhGH treatment: Socioeconomic causes and effect on children's growth

BACKGROUND

In children with growth disorders, mean final height is associated to poor adherence to Growth Hormone therapy. The primary goal of this study is to identify patients who do not adhere to GH therapy and determine the influence of adherence in response to the treatment. The role of serum IGF-I and influence of socio-economic factors on the therapeutic adherence will also be evaluated.

METHODS

158 children under treatment with rhGH were included in the study. Age, gender, etiology, Tanner stage, duration of treatment, growth rate, IGF-I serum values, daily dose, and annual rhGH dose data were collected. Adherence to therapy was defined as moderate-to-poor when the patient had taken less than 92% of the prescribed medication. A subgroup of 106 patients completed a questionnaire to assess social and environmental effects.

RESULTS

Moderate-to-poor adherence to rhGH treatment was determined in 33.5% of study patients. A decrease in adherence was associated to treatment duration (p=0.001). A significant correlation was determined between adherence and height velocity (p=0.002) and IGF-I (p<0.0001) levels. Adherence rates were associated to the mother's educational level (p=0.007).

CONCLUSION

Poor adherence to GH therapy was observed in one-third of study patients, resulting in suboptimal growth. IGF-I levels can be helpful to identify patients with poor adherence to GH medication. Physicians should pay special attention to certain characteristics of the patient and their environment, and encourage desirable therapeutic compliance.

Development of a Transnasal Delivery System for Recombinant Human Growth Hormone (rhGH): Effects of the Concentration and Molecular Weight of Poly-L-arginine on the Nasal Absorption of rhGH in Rats

A novel system for delivering recombinant human growth hormone (rhGH) that is noninvasive and has a simple method of administration is strongly desired to improve the compliance of children. The aim of this study was to investigate the potential for the intranasal (i.n.) co-administration of rhGH with poly-L-arginine (PLA) as a novel delivery system by evaluating the effects of the concentration and molecular weight of PLA on the nasal absorption of rhGH. The influence of the formation of insoluble aggregates and a soluble complex in the dosage formulation on nasal rhGH absorption was also evaluated by size-exclusion chromatography and ultrafiltration. PLA enhanced the nasal absorption of rhGH at each concentration and molecular weight examined. Nasal rhGH absorption increased dramatically when the PLA concentration was 1.0 % (w/v) due to the improved solubility of rhGH in the formulation. A delay in rhGH absorption was observed when the molecular weight of PLA was increased. This appeared to be because the increase in molecular weight caused the formation of a soluble complex. It seems that the PLA concentration affects the absorption-enhancing effect on rhGH, while the molecular weight of PLA affects the time when the maximum plasma rhGH concentration was reached (Tmax) of rhGH after i.n. administration, mainly because of the interactions among rhGH, PLA, and additives. Therefore, the transnasal rhGH delivery system using PLA is considered to be a promising alternative to subcutaneous (s.c.) injection if these interactions are sufficiently controlled.

Growth hormone (GH) dose-dependent IGF-I response relates to pubertal height gain

BACKGROUND

Responsiveness to GH treatment can be estimated by both growth and ∆IGF-I. The primary aim of the present study was to investigate if mimicking the physiological increase during puberty in GH secretion, by using a higher GH dose could lead to pubertal IGFs in short children with low GH secretion. The secondary aim was to explore the relationship between IGF-I, IGFBP-3 and the IGF-I/IGFBP-3 ratio and gain in height.

METHODS

A multicentre, randomized, clinical trial (TRN88-177) in 104 children (90 boys), who had received GH 33 μg/kg/day during at least 1 prepubertal year. They were followed from GH start to adult height (mean, 7.5 years; range, 4.6-10.7). At onset of puberty, children were randomized into three groups, to receive 67 μg/kg/day (GH(67)) given once (GH(67x1); n = 30) or divided into two daily injection (GH(33x2); n = 36), or to remain on a single 33 μg/kg/day dose (GH(33x1); n = 38). The outcome measures were change and obtained mean on-treatment IGF-I(SDS), IGFBP3(SDS) and IGF-I/IGFBP3 ratio(SDS) during prepuberty and puberty. These variables were assessed in relation to prepubertal, pubertal and total gain in heightSDS.

RESULTS

Mean prepubertal increases 1 year after GH start were: 2.1 IGF-I(SDS), 0.6 IGFBP3(SDS) and 1.5 IGF-I/IGFBP3ratio(SDS). A significant positive correlation was found between prepubertal ∆IGFs and both prepubertal and total gain in height(SDS). During puberty changes in IGFs were GH dose-dependent: mean pubertal level of IGF-I(SDS) was higher in GH(67) vs GH(33) (p = 0.031). First year pubertal ∆IGF-I(SDS) was significantly higher in the GH(67)vs GH(33) group (0.5 vs -0.1, respectively, p = 0.007), as well as ∆IGF-I(SDS) to the pubertal mean level (0.2 vs -0.2, p = 0.028). In multivariate analyses, the prepubertal increase in '∆IGF-I(SDS) from GH start' and the 'GH dose-dependent pubertal ∆IGF-I(SDS)' were the most important variables for explaining variation in prepubertal (21 %), pubertal (26 %) and total (28 %) gain in height(SDS).

TRIAL REGISTRATION

TRN 88-177, not applicable 1988.

CONCLUSION

The dose-dependent change in IGFs was related to a dose-dependent pubertal gain in height(SDS). The attempt to mimic normal physiology by giving a higher GH dose during puberty was associated with both an increase in IGF-I and a dose-dependent gain in height(SDS).

Intranasal Human Growth Hormone (hGH) Induces IGF-1 Levels Comparable With Subcutaneous Injection With Lower Systemic Exposure to hGH in Healthy Volunteers

CONTEXT

The development of an improved, efficacious human GH (hGH) product administered by a noninjectable route of delivery such as the nasal route is highly desirable. We have developed a novel nasal hGH product (CP024) that showed excellent nasal absorption in animal models; however, the translation of these results into the clinical setting is essential because past attempts to develop such formulations by other groups have been unable to induce IGF-1 in man.

OBJECTIVE

The objective of the study was to assess the pharmacokinetics, pharmacodynamics, and tolerability of CP024 compared with a sc hGH injection.

DESIGN

This was a single-center, nonrandomized placebo-controlled, open-label, five-way crossover study in eight healthy volunteers.

SETTING

The study was carried out at a contract research organization, Quotient Bioresearch.

VOLUNTEERS

Eight healthy male volunteers, given an iv infusion of octreotide to suppress the endogenous GH secretion during the study period, participated in the study. No volunteers were withdrawn due to side effects.

MAIN OUTCOME MEASURES

Measurement of hGH and IGF-1 levels and tolerability of the drug product was performed.

RESULTS

No serious adverse events were reported and no subjects withdrawn from study due to the treatment. After the nasal administration of CP024, 3-fold higher hGH blood levels were obtained as compared with hGH nasal control. The relative bioavailability was about 3%. CP024 (given twice daily) induced a significant increase in IGF-1 levels up to 19 hours after administration, with no significant difference to those obtained after the sc injection of hGH.

CONCLUSIONS

The study indicates that CP024 is a promising candidate for an efficacious nasal product for the treatment of GH deficiency due to induction of IGF-1 similar to that after a sc injection, despite the lower plasma hGH concentration obtained. A dose-response study is needed to evaluate the optimal nasal dose.

Extension of in vivo half-life of biologically active molecules by XTEN protein polymers

XTEN™ is a class of unstructured hydrophilic, biodegradable protein polymers designed to increase the half-lives of therapeutic peptides and proteins. XTEN polymers and XTEN fusion proteins are typically expressed in Escherichia coli and purified by conventional protein chromatography as monodisperse polypeptides of exact length and sequence. Unstructured XTEN polypeptides have hydrodynamic volumes significantly larger than typical globular proteins of similar mass, thus imparting a bulking effect to the therapeutic payloads attached to them. Since their invention, XTEN polypeptides have been utilized to extend the half-lives of a variety of peptide- and protein-based therapeutics. Multiple clinical and preclinical studies and related drug discovery and development efforts are in progress. This review details the most current understanding of physicochemical properties and biological behavior of XTEN and XTENylated molecules. Additionally, the development path and status of several advanced drug discovery and development efforts are highlighted.

Status of long-acting-growth hormone preparations--2015

Growth hormone (GH) treatment has been an established therapy for GH deficiency (GHD) in children and adults for more than three decades. Numerous studies have shown that GH treatment improves height, body composition, bone density, cardiovascular risk factors, physical fitness and quality of life and that the treatment has few side effects. Initially GH was given as intramuscular injections three times per week, but daily subcutaneous injections were shown to be more effective and less inconvenient and the daily administration has been used since its introduction in the 1980s. However, despite ongoing improvements in injection device design, daily subcutaneous injections remain inconvenient, painful and distressing for many patients, leading to noncompliance, reduced efficacy and increased health care costs. To address these issues a variety of long-acting formulations of GH have been developed. In this review we present the current status of long-acting GH preparations and discuss the specific issues related to their development.

Adherence to growth hormone therapy: a practical approach

BACKGROUND

Early detection of suspected poor adherence to growth hormone (GH) therapy is crucial to achieve normal final height in GH-deficient (GHD) patients.

PATIENTS

106 children (73 M, 33 F) with a median age of 10.47±3.48 years (mean±standard deviation score (SDS)) exhibited short stature (-1.76±0.64 SDS) and a delayed bone age (8.68±3.42 years). Severe GHD was found in 28, while partial GHD was seen in 78 cases, with low IGF-I values. Recombinant human GH was administered by daily subcutaneous injection at a dosage of 21 µg/kg in prepubertal and 25 µg/kg in pubertal patients.

RESULTS

Poor adherence was suspected in a number of patients, but clearly demonstrated in only 4 cases with persistent reduced height velocity in spite of a corrected therapeutic regimen. These patients admitted incomplete adherence to GH injections and clinical and anthropometric measurements revealed their poor response to therapy.

CONCLUSIONS

To efficaciously improve adherence in GHD patients, it is mandatory to regularly interview patients; a non-aggressive approach might be utilized to ensure effective communication with patients and their parents.

An analysis of product wastage arising from dosing increment granularity in four modern growth hormone administration devices

OBJECTIVE

Human growth hormone (hGH) delivery systems differ in the size of the dose increments that can be set by the patient, affecting proximity to the target (i.e., prescribed) dose which can be attained. We investigated differences in dosing increment granularity in NordiFlex®, FlexPro®, NordiPen® (all multiple dose devices) and MiniQuick® (single dose) delivery systems.

METHODS

A simulation model was developed to project hGH dosing in pediatric patients with growth hormone deficiency, small for gestational age or Turner syndrome, calculating the nearest dose above the target dose administrable by each device in typical EU and US cohorts and projecting the excess dose (hGH wastage) over 1 year of typical use.

RESULTS

The device with the smallest dosing increment (FlexPro 5 mg; 0.025 mg dosing increment) was projected to administer doses < 1% above the target across all indications. MiniQuick (0.2 mg dosing increment) was projected to deliver between 5 and 6% above the target dose. None of the sensitivity analyses changed the conclusion that larger dosing increments result in more hGH wastage.

CONCLUSIONS

In addition to increasing dosing accuracy, finer dosing increments may result in reductions in unnecessary hGH usage, which may in turn result in reductions in the cost of hGH treatment borne by the health-care payer.

Growth hormone replacement in adults - current standards and new perspectives

Growth hormone deficiency (GHD) in adults is an established clinical syndrome characterised by adverse body composition with more body fat than lean body mass, unfavourable blood lipids, decreased physical fitness and poor quality of life. No specific biomarker for GHD exists and the sometimes difficult diagnosis should be made in accordance with, established guidelines. Measurements of insulin-like growth factor I (IGF-I) is often not sufficient for the diagnosis and stimulation tests of the GH reserve are required. After diagnosis of GHD, treatment with GH should be initiated with a low dose, and gradually increased aiming at obtaining an IGF-I level within the upper part of the normal range for age matched healthy controls. Most side effects are mild and transient and attenuated by gradual dose increments. Numerous studies have shown that GH treatment can improve body composition, cardiovascular risk factors, physical capacity and quality of life. However, studies on effects beyond 5 years are few and despite encouraging preliminary reports the ultimate endpoint demonstrating that GH treatment has beneficial effects on mortality, cardiovascular events and fractures without an increase in cancer incidence remain to be solidly demonstrated and studies to resolve these issues are awaited. Trials with long acting GH formulations are ongoing and available data indicate similar effects on outcome measures compared to the effects of daily injections. This review will give an overview of clinically relevant issues of GHD including advice for management of these patients.

Isolated growth hormone deficiency (GHD) in childhood and adolescence: recent advances

The diagnosis of GH deficiency (GHD) in childhood is a multistep process involving clinical history, examination with detailed auxology, biochemical testing, and pituitary imaging, with an increasing contribution from genetics in patients with congenital GHD. Our increasing understanding of the factors involved in the development of somatotropes and the dynamic function of the somatotrope network may explain, at least in part, the development and progression of childhood GHD in different age groups. With respect to the genetic etiology of isolated GHD (IGHD), mutations in known genes such as those encoding GH (GH1), GHRH receptor (GHRHR), or transcription factors involved in pituitary development, are identified in a relatively small percentage of patients suggesting the involvement of other, yet unidentified, factors. Genome-wide association studies point toward an increasing number of genes involved in the control of growth, but their role in the etiology of IGHD remains unknown. Despite the many years of research in the area of GHD, there are still controversies on the etiology, diagnosis, and management of IGHD in children. Recent data suggest that childhood IGHD may have a wider impact on the health and neurodevelopment of children, but it is yet unknown to what extent treatment with recombinant human GH can reverse this effect. Finally, the safety of recombinant human GH is currently the subject of much debate and research, and it is clear that long-term controlled studies are needed to clarify the consequences of childhood IGHD and the long-term safety of its treatment.

Growth hormone treatment adherence in prepubertal and pubertal children with different growth disorders

BACKGROUND/AIMS

Treatment of children with growth disorders with recombinant human growth hormone is necessary for improved outcomes, including final height.

METHODS

Adherence data from the Observational Study Saizen®-online, recorded with the easypod™ device collected between October 2009 and May 2011, were analyzed in pediatric patients receiving recombinant human growth hormone treatment for a variety of growth disorders.

RESULTS

Data from 75 children (46 boys, 29 girls) with different growth disorders were analyzed over a period of 343 ± 201 (SD) days. Boys and girls showed similar mean ± SD adherence rates of 90.5 ± 3.1% and 92.2 ± 10.7%, respectively. Pubertal children (n = 41) had a significantly lower adherence rate (89.1 ± 13.7%) than prepubertal children (n = 29) (96.5 ± 3.9%; p < 0.005). There were nonsignificant differences in adherence rates according to diagnosis: growth hormone deficiency (n = 48) 91.4 ± 11.0%, small for gestational age (n = 18) 91.1 ± 15.3%, Turner syndrome (n = 6) 86.0 ± 14.5%, and chronic renal failure (n = 3) 99.3 ± 1.0%, although the latter two groups were small.

CONCLUSION

Our data indicate that only a small number of pediatric patients using the easypod device had poor adherence to treatment. Further reliable adherence data are required to identify factors affecting long-term adherence in this population.

Comparison of weight- vs body surface area-based growth hormone dosing for children: implications for response

OBJECTIVE

To compare weight (per kg)- vs body surface area (BSA, per m(2) )-based growth hormone (GH) dosing formats in children and to derive a useful conversion formula between the two formats.

PATIENTS AND DESIGN

Growth hormone doses (>33,000) from 1874 children were obtained from the national Australian database (OZGROW) and used to derive conversion formulae and to confirm the accuracy of a conversion formula based on a weight-only BSA estimate. A further 27,000 doses were used to test the accuracy of all formulae. The best conversion formula was used to compare weight- and surface area-based GH dosing, which included an analysis of first year response (∆SDS height or growth velocity, GV).

MEASUREMENTS

Growth hormone doses in mg/m(2) /wk and mg/kg/wk, dose estimates, residuals, first year ∆SDS, first year GV.

RESULTS

The formula, [Formula: see text] based on a weight-only BSA estimate, provides accurate dose conversion (mean residual, 0·005 mg/kg/week). A constant mg/m(2) /week dose expressed in terms of mg/kg/week declines quickly with increasing body weight to approximately 15 kg after which the decline continues although less dramatically. For Australian patients, despite an increase in mean per m(2) dose with increased starting weight/age, the per kg dose decreased. This was associated with a greater decline in first year GV than estimated if a per kg dose had been maintained.

CONCLUSIONS

Growth hormone doses can be accurately converted between formats. Surface area-based GH dosing is likely to result in a reduced height response as children become heavier when compared with weight-based GH dosing.

Understanding the growth hormone therapy adherence paradigm: a systematic review

INTRODUCTION

Growth hormone (GH) therapy is used to treat a variety of growth disorders in childhood/adolescence. Its efficacy is thought to be dependent on patients' adherence to their treatment regimen.

METHODS

PubMed was searched using the keywords 'growth hormone', 'child'[Mesh], 'adolescent'[Mesh], and 'patient compliance'[Mesh].

RESULTS

Most studies of adherence to paediatric GH therapy have used either issued/encashed GH prescriptions or questionnaires. Estimates of prevalence of non-adherence vary from 5-82%, depending on the methods and definitions used. Different studies have variously demonstrated an association (or lack thereof) between adherence and age, socioeconomic status, treatment duration, injection device used and injection-giver. A number of interventions have been proposed to improve adherence, including offering a choice of injection device, but none are supported by trials. Poor adherence is associated with reduced height velocity and likely increased economic costs; evidence for other effects is circumstantial.

CONCLUSION

Adherence to paediatric GH therapy is suboptimal, which may partially explain why the mean final height attained is below that of the general population. Analysis of the causes of non-adherence is complicated by conflicting evidence from different studies. Multifactorial interventions are most likely to be successful in improving adherence. We make recommendations for further research.