Mal-PEG molecule reacted with Cys of interferon to achieve site-specific pegylation. The advantage  of this technology is to make the purification process simpler which  results in high yielding, uniform structure, and lower manufacturing cost.

“Interferon alpha mutant and polyethylene glycol derivatives”PCT patent has been authorized in the United States, Japan, South Korea, China. (PCT/CN2007/003711)