A Follow-up Study to Monitor Adult Height Among Spanish Children with Growth Hormone Deficiency Who Received Biosimilar Human Recombinant Growth Hormone (Omnitrope®) During a Phase III Clinical Trial

Introduction An initial Phase III clinical trial has evaluated the efficacy and safety of biosimilar recombinant human growth hormone (rhGH; Omnitrope ® , Sandoz) in Spanish children with growth hormone deficiency (GHD). At the end of the study, those patients still growing were offered to remain on treatment (as in usual clinical practice), and continued to be monitored. The aim of this study was to determine the adult height achieved by the Spanish children who participated in the initial Phase III clinical trial, and to evaluate the long-term safety of rhGH treatment. Methods This study was a multicenter, observational, retrospective follow-up study of patients who participated in the Phase III clinical trial (70 patients recruited). Auxological parameters [including height, height velocity, and their associated height standard deviation scores (HSDS)] were obtained from 39 patients. Safety was assessed by recording any adverse events (AEs). Results In total, 27 men and 12 women provided auxological data. At the start of the follow-up study, the mean age of the patients was 12.5 ± 2.7 years, mean height was 144.8 ± 13.9 cm and mean HSDS was −1.16 ± 0.63. By the end of the follow-up period, mean height had increased to 163.1 ± 7.6 cm ( n = 36; men 165.5 ± 7.8 cm, women 157.6 ± 3.2 cm) and mean HSDS also increased to −1.01 ± 0.59 ( n = 36; men −1.07 ± 0.52, women −0.86 ± 0.72). In terms of safety, no treatment-related AEs were reported during the study. Conclusion This cohort of Spanish patients with GHD showed a positive response to rhGH treatment, achieving adult height within the local normal ranges. In addition, rhGH treatment was well tolerated, with no new or additional safety concerns.