GC Biopharma releases long-term clinical study of Hunterase at SSIEM 2024

GC Biopharma said Tuesday that it unveiled the long-term extension clinical results of the phase 3 Hunterase trial through a poster presentation at the Society for the Study of Inborn Errors of Metabolism’s annual symposium, SSIEM 2024, in Portugal.

Professor Cho Sung-yoon of the Department of Pediatric Endocrinology, Genetics, and Metabolism at Samsung Medical Center presented the study.

SSIEM is a rare inherited metabolic disease society. SSIEM 2024 was held in Porto, Portugal, from Tuesday to Friday of last week, in local time.

The presentation included results from a two-year extension of patients in the phase 3 Hunterase trial, which ended last year. The study looked at changes in the Six-Minute Walk Test (6-MWT) and urinary glycosaminoglycans (GAGs) in patients treated with Hunterase once weekly intravenously for two years and in patients treated with one year of idursulfase followed by one year of switching to Hunterase.

The study confirmed the results of the long-term safety and efficacy assessments in patients who received Hunterase continuously for two years and in patients who switched from idursulfase to Hunterase. It also demonstrated a statistically significant percent change from baseline in the Six-Minute Walk Test and urine GAG.

Notably, in patients who switched to Hunterase, an increase in the 6-MWT was observed in the first year, followed by an additional increase in the second year.

No adverse events differed from those seen with conventional therapy, demonstrating the safety and efficacy of Hunterase in the long term.

“These results demonstrate the continued efficacy and safety of Hunterase over the long term and confirm that patients receiving idursulfase as an enzyme replacement therapy for Mucopolysaccharidosis Type II (MPSII) can be safely switched to Hunterase,” said Shin Soo-Kyung, head of Medical Division at GC Biopharma.

Hunterase is the world’s second treatment for Hunter syndrome, which GC Biopharma developed. Hunter syndrome, also known as type 2 mucopolysaccharidosis, is a rare disease that affects an estimated one in 100,000 to 150,000 male children. Based on the confirmatory data from the phase 3 study of Hunterase, GC Biopharma received approval from the Ministry of Food and Drug Safety last November to upgrade the conditional license to a full license.