Somapacitan in children born small for gestational age: a randomized controlled phase 3 trial

Short stature in children born small for gestational age (SGA) is treated with daily injections of recombinant growth hormone (GH), a significant treatment burden. The objective of this study is to demonstrate the efficacy and safety of once-weekly somapacitan, a long-acting GH, in short children born SGA.

REAL8 (NCT05330325) is a multinational, multicenter, randomized, open-labeled, active comparator, phase 3 basket study including four non-GH deficiency indications comprising a 52-week main phase and 104-week extension. Here, we present 52-week results from the SGA sub-study.

142 prepubertal, treatment-naïve children born SGA in 78 sites across 26 countries were randomized 2:1:1 to somapacitan .24 mg/kg/week or daily GH 0.035 or 0.067 mg/kg/day, all administered subcutaneously. 140 completed the main 52-week treatment period.

The primary endpoint, estimated mean height velocity at week 52, was 11.0 cm/year for somapacitan vs. 9.4 cm/year [ETD = 1.6(0.91, 2.23)95%CI] and 11.1 cm/year [ETD = -0.1(-0.75, 0.60)95%CI] for daily GH 0.035 and 0.067 mg/kg/day, respectively. Noninferiority was confirmed for somapacitan compared to both daily GH groups. Superiority was demonstrated for somapacitan versus daily GH 0.035 mg/kg/day. Safety profiles were similar between treatment groups. As expected, somapacitan reduced disease burden at week 52, as for daily GH 0.067 mg/kg/day, while somapacitan was associated with reduced treatment burden.

Somapacitan provides similar efficacy, safety, and tolerability as daily GH in short children born SGA after 52 weeks of treatment. Somapacitan may be an attractive alternative to daily GH in this population, reducing treatment burden to improve adherence and treatment outcomes.