Efficacy and safety of the recombinant human growth hormone in short children born small for gestational age: A randomized, multicentre, comparative phase III trial

OBJECTIVE

Growth hormone (GH) treatment is known to be effective in increasing stature in children with a short stature born small for gestational age (SGA). This multicentre, randomized, open-label, comparative, phase III study aimed to evaluate the efficacy and safety of Growtropin-II (recombinant human GH) and to demonstrate that the growth-promoting effect of Growtropin-II is not inferior to that of Genotropin in children with SGA (NCT ID: NCT02770157).

METHODS

Seventy five children who met the inclusion criteria were randomized into 3 groups in a ratio of 2:2:1 (the study group [Growtropin-II, n = 30], control group [Genotropin, n = 30], and 26-week non-treatment group [n = 15]). The study and control groups received subcutaneous injections of Growtropin-II and Genotropin, respectively for 52 weeks, whereas the non-treatment group underwent a non-treatment observation period during weeks 0 to 26 and a dosing period during weeks 27 to 52 and additional dosing till week 78 only in re-consenting children.

RESULTS

No significant differences in demographic and baseline characteristics between the groups were observed. The mean ± standard deviation change difference in annualized height velocity (aHV) (study group - control group) was 0.65 ±2.12 cm/year (95% confidence interval [CI], -0.53 to 1.83), whereas the lower limit for the 2-sided 95% CI was -0.53 cm/year. Regarding safety, treatment-emergent adverse events (TEAEs) occurred in 53.33% children in the study group and 43.33% children in the control group; the difference in the incidence of TEAEs between the 2 treatment groups was not statistically significant (P  = .4383). A total of 17 serious adverse events (SAEs) occurred in 13.33% children in the treatment groups, and no significant difference in incidence between groups (P  = .7065) was seen. Two cases of adverse drug reaction (ADR) occurred in 2 children (3.33%): 1 ADR (injection site swelling or pain) occurred in 1 child (3.33%) each in the study and control groups.

CONCLUSIONS

This study demonstrates that the change in aHV from the baseline till 52 weeks with Growtropin-II treatment is non-inferior to that with Genotropin treatment in children with short stature born SGA. Growtropin-II is well-tolerated, and its safety profile is comparable with that of Genotropin over a 1-year course of treatment.

Long-term care, from neonatal period to adulthood, of children born small for gestational age

Children born small for gestational age (SGA) face an increased risk of health problems in later life, particularly persistent short stature, neurocognitive dysfunction, impaired renal and pulmonary function, decreased bone density, sensorineural hearing loss, premature adrenarche, and metabolic syndrome. Insulin resistance appears to be a key component underlying these metabolic complications. Long-term, continuous, GH treatments in short children born SGA lead to a normalization of height through childhood to adulthood. Recombinant human GH has been proven to be relatively safe. We recommend early surveillance in a growth clinic for children born SGA without catch-up growth. Obesity, insulin resistance, and the risk of metabolic syndrome increase with catch-up growth, but short stature and cognitive dysfunction increase without catch-up growth in children born SGA. A solution to this catch-up dilemma is breast feeding for a minimum of 6 to 12 mo. Because the overall prevalence of metabolic risk factors is very low, routine evaluation of metabolic parameters is not recommended for all children born SGA, but it may be useful to consider metabolic evaluations in overweight or obese children born SGA. Since children born SGA have many risk factors, long-term management from neonate to adulthood is very important.

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.

Efficacy and safety of growth hormone treatment for children born small for gestational age

Recombinant growth hormone (GH) is an effective treatment for short children who are born small for gestational age (SGA). Short children born SGA who fail to demonstrate catch-up growth by 2-4 years of age are candidates for GH treatment initiated to achieve catch-up growth to a normal height in early childhood, maintain a normal height gain throughout childhood, and achieve an adult height within the normal target range. GH treatment at a dose of 35-70 µg/kg/day should be considered for those with very marked growth retardation, as these patients require rapid catch-up growth. Factors associated with response to GH treatment during the initial 2-3 years of therapy include age and height standard deviation scores at the start of therapy, midparental height, and GH dose. Adverse events due to GH treatment are no more common in the SGA population than in other conditions treated with GH. Early surveillance in growth clinics is strongly recommended for children born SGA who have not caught up. Although high dose of up to 0.067 mg/kg/day are relatively safe for short children with growth failure, clinicians need to remain aware of long-term mortality and morbidity after GH treatment.