Interferon

A protein produced and released into the bloodstream by animal cells when they are invaded by a virus. Interferon induces healthy cells to produce antiviral enzymes. Interferon was scarce and expensive until 1980 when the Interferon gene was inserted into bacteria using genetic engineering, allowing mass cultivation and purification from bacterial cultures. It was cleared by the American [Food and Drug Administration]? in February 25 1991 as a treatment for [hepatitis C]?. About half of Hep C patients treated with interferon respond, with better blood tests and better liver biopsies. Half the patients who respond relapse once the interferon is stopped, for a total cure rate of about 25%.