Safety of Novo Nordisk's Growth Hormone Injection Under Scrutiny: Weekly Dosing Raises New Concerns

According to the news published on the official website of China's National Medical Products Administration (CDE) on September 5, Novo Nordisk's market access application for Parsi growth hormone injection (Sogroya) has been officially accepted. Pasil auxin injection contains the active ingredient somapacitan, which is a long-acting variant of human growth hormone (hGH). Somapacitan modifies natural hGH and enhances its affinity with plasma albumin, thus adapting to a weekly dosing regimen. Somapacitan was originally approved by the U.S. Food and Drug Administration (FDA) on September 1, 2020 to treat growth hormone deficiency in adults. Through April 2023, the FDA further expanded the indication for somapacitan to include the treatment of growth hormone deficiency in children 2.5 years of age and older.

According to the Pharmaceutical Rubik's Cube database, Novo Nordisk initiated a Phase III clinical study (CTR20211271) in China in June 2021 for pediatric patients with slow growth due to insufficient growth hormone secretion, which was completed in January this year. The primary objective of the study was to evaluate the efficacy and safety of once-weekly administration of somapacitan versus once-daily administration of Norditropin in children with growth hormone deficiency in China.

There were also positive results from the previous REAL4 study, a multicenter, randomized, open-label Phase III clinical study to evaluate the efficacy and safety of somapacitan in the treatment of growth hormone deficiency in preadolescent children. In the REAL4 study, patients were randomized in a 2:1 ratio to receive a weekly subcutaneous injection of 0.16 mg/kg somapacitan (n=132) or a daily subcutaneous injection of 0.034 mg/kg norditropin (n=68).

The results showed that patients receiving weekly somapacitan had an annualized growth rate of 11.2cm/ year, which was not significantly different from 11.7cm/ year in patients receiving once-daily Norditropin, meeting the primary study endpoint of non-inferior efficacy. In addition, somapacitan has been shown to be well tolerated, with similar safety and tolerability profiles to Norditropin.