GC Pharma’s Hunter syndrome treatment Hunterase has been approved by the Chinese drug authority, the company said Wednesday.

Hunterase is indicated for long-term treatment for Hunter syndrome, and is the first of its kind to be officially approved for use by China’s National Medical Products Administration.

CANBridge Pharmaceuticals is responsible for the distribution of Hunterase in China, and is expected to gradually widen the scope to Taiwan, Hong Kong and adjacent regions.

Hunter syndrome is a rare congenital disease that occurs in about 1 in 150,000 male children. For those who suffer from the illness, enzymatic deficiency of iduronate-2-sulfatase leads to improper digestion of sugar molecules, which causes developmental damages both physically and mentally.

Globally, the number of children with Hunter syndrome is estimated to be around 2,000. However, in China, where there is so far no existing official record of Hunter syndrome patients, the industry estimates there to be 3,000 patients in need of care. The estimation is based on the rate of known disease occurrence. China has designated Hunter syndrome as a rare disease for monitoring since 2018.

Hunterase is an intravenously injectible IDS enzyme made and processed using genetic recombination technology. It was developed in 2012 by GC Pharma as the world’s second Hunter syndrome drug. The first is Sanofi Genzyme’s Elaprase.

Before Hunterase and Elaprase, the average life expectancy of Hunter syndrome patients had been less than 20 years. With lifelong administration of the drugs, a portion of patients have lived into their 30s. There is no drug that completely cures Hunter syndrome.

So far, Hunterase is distributed in 11 nations. China will be the 12th. Sales of Hunterase will be reflected in GC Pharma’s and CANBridge Pharmaceuticals’ performance for 2021.

By Lim Jeong-yeo (kaylalim@heraldcorp.com)