Peginterferon alfa-2a

Peginterferon alfa-2a is a form of recombinant interferon used as part of combination therapy to treat chronic Hepatitis C, an infectious liver disease caused by infection with Hepatitis C Virus (HCV). HCV is a single-stranded RNA virus that is categorized into nine distinct genotypes, with genotype 1 being the most common in the United States, and affecting 72% of all chronic HCV patients . Treatment options for chronic Hepatitis C have advanced significantly since 2011, with the development of Direct Acting Antivirals (DAAs) resulting in less use of Peginterferon alfa-2a. Peginterferon alfa-2a is derived from the alfa-2a moeity of recombinant human interferon and acts by binding to human type 1 interferon receptors. Activation and dimerization of this receptor induces the body's innate antiviral response by activating the janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. Use of Peginterferon alfa-2a is associated with a wide range of severe adverse effects including the aggravation and development of endocrine and autoimmune disorders, retinopathies, cardiovascular and neuropsychiatric complications, and increased risk of hepatic decompensation in patients with cirrhosis. The use of Peginterferon alfa-2a has largely declined since newer interferon-free antiviral therapies have been developed.

In a joint recommendation published in 2016, the American Association for the Study of Liver Diseases (AASLD) and the Infectious Diseases Society of America (IDSA) no longer recommend Peginterferon alfa-2a for the treatment of Hepatitis C . Peginterferon alfa-2a was used alongside Ribavirin with the intent to cure, or achieve a sustained virologic response (SVR), after 48 weeks of therapy. SVR and eradication of HCV infection is associated with significant long-term health benefits including reduced liver-related damage, improved quality of life, reduced incidence of Hepatocellular Carcinoma, and reduced all-cause mortality .

Peginterferon alfa-2a is available as a fixed dose injector (tradename Pegasys) used for the treatment of chronic Hepatitis C. Approved in 2002 by the FDA, Pegasys is indicated for the treatment of HCV with Ribavirin or other antiviral drugs . When combined together, Peginterferon alfa-2a and Ribavirin have been shown to achieve a SVR between 36% for genotype 1 and 59% for genotypes 2-6 after 48 weeks of treatment.

Peginterferon alfa-2a is indicated for the treatment of HCV in combination with other antiviral drugs in patients over 5 years of age with compensated liver disease . May be used as a monotherapy in patients with contraindications to or significant intolerance to other anti-viral therapies.

Peginterferon alfa-2a is also indicated as a monotherapy for adult patients with HBeAg positive and HBeAg negative chronic hepatitis B infection who have compensated liver disease and evidence of viral replication and liver inflammation .