Once-Weekly Somapacitan vs Daily GH in Children With GH Deficiency: Results From a Randomized Phase 2 Trial

CONTEXT

Daily growth hormone (GH) injections can be burdensome for patients and carers. Somapacitan is a long-acting, reversible albumin-binding GH derivative in development for once-weekly administration in patients with growth hormone deficiency (GHD).

OBJECTIVE

The objective of this study is to evaluate the efficacy, safety, and tolerability of once-weekly somapacitan vs once-daily GH.

DESIGN

REAL 3 is a multicenter, randomized, controlled, double-blind (somapacitan doses), phase 2 study with a 26-week main and 26-week extension phase (NCT02616562).

SETTING

This study took place at 29 sites in 11 countries.

PATIENTS

Fifty-nine GH treatment-naive prepubertal children with GHD were randomly assigned; 58 completed the trial.

INTERVENTIONS

Interventions comprised 3 somapacitan doses (0.04 [n = 16], 0.08 [n = 15], or 0.16 mg/kg/wk [n = 14]) and daily GH (0.034 mg/kg/d [n = 14]), administered subcutaneously.

MAIN OUTCOME MEASURES

The primary end point was height velocity (HV) at week 26. Secondary efficacy end points included HV SD score (SDS) and insulin-like growth factor-I (IGF-I) SDS.

RESULTS

At week 26, mean (SD) annualized HV for the somapacitan groups was 8.0 (2.0), 10.9 (1.9), and 12.9 (3.5) cm/year, respectively, vs 11.4 (3.3) cm/year for daily GH; estimated treatment difference (somapacitan 0.16 mg/kg/week-daily GH): 1.7 [95% CI -0.2 to 3.6] cm/year. HV was sustained at week 52, and significantly greater with somapacitan 0.16 mg/kg/week vs daily GH. Mean (SD) change from baseline in HV SDS at week 52 was 4.72 (2.79), 6.14 (3.36), and 8.60 (3.15) for the somapacitan groups, respectively, vs 7.41 (4.08) for daily GH. Model-derived mean (SD) IGF-I SDS for the somapacitan groups was -1.62 (0.86), -1.09 (0.78), and 0.31 (1.06), respectively, vs -0.40 (1.50) observed for daily GH. Safety and tolerability were consistent with the profile of daily GH.

CONCLUSIONS

In children with GHD, once-weekly somapacitan 0.16 mg/kg/week provided the closest efficacy match with similar safety and tolerability to daily GH after 26 and 52 weeks of treatment. A short visual summary of our work is available (1).

Isolated growth hormone deficiency in Chilean patients: clinical and molecular analysis

Isolated growth hormone deficiency (IGHD) is a disorder that leads to short stature. It has been classified into types IA, IB, II and III. GH gene mutations and growth hormone releasing hormone (GHRH) receptor gene mutations have been described in patients with IGHD. We report here a clinical and molecular study of 27 Chilean patients with IGHD. We performed GH stimulation tests with GHRH and GHRP, and segregation and molecular analysis of the GH, GHRH and GHRH receptor genes. We describe four patients with IGHD IA bearing a 7 kb mutation (13%), and two IGHD II patients who showed two different splice site point mutations (6.8%). In 21 patients, we did not find a mutation in any of the three genes examined. These results led us to conclude that the molecular causes of IGHD involve other genes besides those analyzed in this report, as has been reported previously in patients of different ethnic origins.

Inhibitory effect of norditerpenes on LPS-induced TNF-alpha production from the Okinawan soft coral, Sinularia sp

An ethanol (EtOH) extract of the soft coral (Sinularia sp.), collected in Okinawa, demonstrated a potent inhibitory effect on lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF-alpha) production by murine macrophage-like cells (RAW264.7). The activity-guided purification of the EtOH extract resulted in the isolation of two norditerpenes, norcembrenolide (1) and sinuleptolide (2). These structures were identified from the spectroscopic data. Norcembrenolide (1) and sinuleptolide (2) inhibited TNF-alpha production in a dose-dependent manner, and showed a more potent effect than prednisolone at the concentration of 33 microg/ml. They also exhibited an inhibitory effect on nitric oxide (NO) production not influenced by cytotoxicity.

[Comparative study on livertaxis of lactosaminated human growth hormone and galactosyl-human growth hormone]

This study was conducted to compare the livertaxis of lactosaminated human growth hormone (hGH-L) with that of galactosyl human growth hormone (hGH-Gal), using radioactive tracer technique. hGH-L and hGH-Gal were first prepared. After hGH-L, hGH-Gal and hGH were labelled with 131I or 125I, the data on biodistribution in mice, imaging in rabbits and chicken were obtained. hGH-L and hGH-Gal had remarkable livertaxis and their percentages for uptake in liver were 68.83%-74.65% and 68.18%-74% respectively, which were about two times as high as that of hGH. All of the hepatic bindings were receptor-mediated. But, the synthesizing of hGH-L was more easy-to-do, more mild in reaction conditions, and more economical of raw material as compared with the synthesizing of hGH-Gal. Therefore, hGH-L is a more potential receptor-mediated hepatic targeting secreting somatomedian drug for treating dwarfism.