Evaluation of the safety and efficacy of biosimilar recombinant growth hormone in children with growth hormone deficiency: non-inferiority, randomized, parallel, multicentric and Phase III trial

Objectives: This study is designed in order to compare the efficacy and safety of recombinant human growth hormone (rhGH) with the reference brand. Methods: According to the inclusion criteria, 85 people in 13 Iranian centers were randomly selected to receive biosimilar Somatropin (Somatin®) (44 people) and reference Somatropin (Norditropin®) (41 people) at a dose of 35 µg/kg/d, seven days/week for 12 months. The primary outcomes included height velocity (HV) was measured during 12 months of treatment. Results: The two intervention groups’ Height changes were similar. The mean HV was 10.96 cm/year in the biosimilar group and 10.05 cm/year in the reference groups after 12 months. Estimates of the lower bounds of 95% CI for mean height differences in the biosimilar intervention group compared to the reference intervention group did not exceed the 2 cm margin. Therefore, the non-inferiority of biosimilar intervention compared to the brand product is verified. Common ADRs in both groups were nausea in two patients (2.4%), diarrhea in two patients (2.4%), increased body temperature in one patient (1.2%), and headache in one patient (1.2%). Conclusions: The finding of this study indicated that Somatin® and Norditropin® have comparable efficacy and safety profiles. Clinical trial registration: www.IRCT.irIRCT20171122037571N1.