Somapacitan in children born small for gestational age: 4-year results from phase 2

OBJECTIVE: Evaluate long-term efficacy, safety, and tolerability of once-weekly somapacitan, a long-acting growth hormone (GH) derivative, in children born small for gestational age (SGA) with short stature, including after switching from daily GH.

DESIGN: REAL5 (NCT03878446) is a global, randomized, open-label, controlled phase 2 study comprising a 26-week main phase, 26-week extension I, and an ongoing 4-year extension II.

METHODS: Sixty-two children born SGA with short stature were recruited at 38 clinics across 12 countries and randomized (1:1:1:1:1) to somapacitan (0.16, 0.20, or 0.24 mg/kg/week) or daily GH (0.035 or 0.067 mg/kg/day) until week 52 (inclusive main phase and extension I). Sixty participants entered extension II. Forty-eight participants switched to somapacitan 0.24 mg/kg/week from cohorts randomized to daily GH or lower somapacitan doses. Fifty-five children completed 208 weeks of treatment. Novel safety and efficacy results from week 52 to 208 are presented here.

RESULTS: Across all treatment arms, continuous increases in height standard deviation scores were observed from week 52 to week 208, including after switch to somapacitan 0.24 mg/kg/week. The safety and tolerability profile for somapacitan 0.24 mg/kg/week was similar to the well-established safety and tolerability profile for daily GH in SGA. Patient preference questionnaire results indicate that most respondents (87%) prefer somapacitan over daily GH. Most respondents (80%) answered that they expect to be more adherent to treatment with somapacitan.

CONCLUSIONS: These results support long-term continuous efficacy, safety, and tolerability of GH therapy with somapacitan 0.24 mg/kg/week for up to 4 years in children born SGA, including after switching from daily GH.

CLINICALTRIALS.GOV: NCT03878446.