PEG-Intron A is a modified form of Schering-Plough’s Intron A (interferon alpha-2b, recombinant), developed by Enzon, Inc. to have longer-acting properties. PEG-Intron A is administered once a week, compared to the normal dosage of 3 times a week for Intron A.
“Consistent with previous studies, the rates of sustained virologic response achieved in this study (Phase III clinical trials) were greatly influenced by genotype, and ranged from 11% for patients with genotype 1, the predominant genotype worldwide and the most difficult to treat, to 49% for patients with genotype 2 or 3, compared to 6% to 28% for INTRON A.'' (Christian Trepo, M.D., Ph.D., director, hepatitis research unit, Hopital Hotel Dieu, Service d'Hepatologie, Lyon, France).
Peg-Intron A was approved in Europe in May 2000, and was the first pegylated interferon to be approved, worldwide.