Handok and Genexine presented the results of the Phase 2 clinical trials conducted in Korea and Europe of the long-acting growth hormone GX-H9 at the 57th Annual Meeting of the European Society for Paediatric Endocrinology (ESPE).

GX-H9 is a long-acting growth hormone, made using Genexine’s proprietary hybrid Fc technology, jointly developed by Handok and Genexine. The growth hormone is intended for weekly or twice-monthly administration.

The results presented this year were from the Phase 2 clinical studies for GX-H9, conducted on children at 27 endocrinology centers in 10 countries, including European countries and Korea. During the trials, the height velocities of a total of 50 patients—one group treated with Genotropin® and two groups treated with differing amounts of GX-H9—were recorded over the course of 12 months. The results showed that the annualized height velocity of the control group (those treated with a daily dose of Genotropin®) was 9.14 cm on average, while the annualized height velocity of groups treated weekly with 0.8 mg/kg and 1.2 mg/kg of GX-H9 were 10.50 cm and 11.76 cm, respectively. The group administered 2.4 mg/kg of GX-H9 twice monthly showed an annualized height velocity of 11.03 cm, which was larger than the control group. 

There was no significant decline of the growth rate after 12 months of treatment compared to the growth rate results published after six months. Moreover, there were no reported side effects, such as lipoatrophy at the site of injection or insulin resistance, and the GX-H9 treatment groups showed similar levels of safety as the group treated with Genotropin®. In particular, groups that were treated once or twice a week with GX-H9 showed superior growth rates compared to the control group. These results show the potential of GX-H9 as a long-acting growth hormone that can be administered weekly or biweekly.

GX-H9 was selected as a Full-Cycle New Medicine Development Project by the Korea Drug Development Fund (CEO Muk Hyunsang), which supports the research and development of new global medicine. The global Phase 2 clinical trials for GX-H9, conducted on patients suffering from pediatric growth hormone deficiency (PGHD), were approved and have been conducted, and research for global out-licensing is ongoing.

Handok and Genexine are strategic partners and, in June 2012, signed a technology licensing and joint development agreement for the long-acting growth hormone. In 2014, Handok became Genexine’s largest shareholder. In recognition of its technological excellence, the long-acting growth hormone GX-H9 was selected as a project financed by the Korea Drug Development Fund, and, in 2016, received the Orphan Drug Designation by the United States Food and Drug Administration (FDA) for the treatment of growth hormone deficiencies. Following the Phase 2 clinical trials for adults and children in European countries and Korea, Handok and Genexine will submit a request to the U.S. FDA for approval to enter Phase 3 clinical trials early next year.