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An Overview of Pegasys (Peginterferon Alfa-2a)

August 28, 2017

Brand Name: Pegasys
Other Names: PEG-interferon alfa-2a (HBV, HCV), pegIFN alfa-2a (HBV, HCV), pegylated-interferon alfa 2a (HBV, HCV)
Drug Class: Opportunistic Infections and Coinfections

What Is Peginterferon Alfa-2a?

Peginterferon alfa-2a is an antiviral prescription medicine approved by the U.S. Food and Drug Administration (FDA) for the treatment of chronic hepatitis B virus (HBV) infection and chronic hepatitis C virus (HCV) infection. HBV and HCV infections are HIV-related opportunistic infections. An opportunistic infection is an infection that occurs more frequently or is more severe in people with weakened immune systems -- such as those living with HIV -- than in people with healthy immune systems. To learn more about opportunistic infections, read the AIDSinfo What is an Opportunistic Infection? fact sheet. To learn how HIV and HBV and HCV infections are connected, read the AIDSinfo HIV and Hepatitis B and HIV and Hepatitis C fact sheets. 

The Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents (Adult OI Guidelines), prepared by the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), and the HIV Medicine Association of the Infectious Diseases Society of America (IDSA-HIVMA) include recommendations on the use of peginterferon alfa-2a to treat HBV infection in people with HIV.

The Adult OI Guidelines refer readers to the Hepatitis C Guidance: AASLD-IDSA Recommendations for Testing, Managing, and Treating Adults Infected with Hepatitis C Virus for recommendations on the treatment of HCV infection in people with HIV. The Hepatitis C Guidance is prepared by the American Association for the Study of Liver Diseases (AASLD), the Infectious Diseases Society of America (IDSA), and the International Antiviral Society-USA (IAS-USA). Although peginterferon alfa-2a is approved for the treatment of chronic HCV infection, the IDSA-AASLD Hepatitis C Guidance recommends against the use of peginterferon-containing regimens to treat HCV infection, including in people with HIV. New, recently approved HCV drugs offer more effective, better tolerated treatment options. 

Please refer to the Adult OI Guidelines and the IDSA-AASLD Hepatitis C Guidance for more information.


What Should I Tell My Health Care Provider Before Taking Peginterferon Alfa-2a?

Before taking peginterferon alfa-2a, tell your health care provider:

  • If you are allergic to peginterferon alfa-2a or any other medicines.
  • About any medical conditions you have or have had, for example, diabetes or liver problems.
  • About any health conditions that may prevent you from receiving medicine by injection.
  • If you are pregnant or plan to become pregnant. Whether peginterferon alfa-2a will harm an unborn baby is unknown. Talk to your health care provider about possible risks with taking peginterferon alfa-2a when pregnant. Peginterferon alfa-2a may be given with another medicine called ribavirin. Because ribavirin may cause birth defects or death of an unborn child, ribavirin should not be used by pregnant women or by men whose partners are pregnant.
  • If you are breastfeeding or plan to breastfeed. Do not breastfeed if you have HIV.
  • About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Peginterferon alfa-2a may affect the way other medicines or products work, and other medicines or products may affect how peginterferon alfa-2a works. Ask your health care provider if there are interactions between peginterferon alfa-2a and the other medicines you take.

Ask your health care provider about possible side effects from peginterferon alfa-2a. Your health care provider will tell you what to do if you have side effects.

How Should I Take Peginterferon Alfa-2a?

Take peginterferon alfa-2a according to your health care provider's instructions. Your health care provider will tell you how much peginterferon alfa-2a to take and when to take it. Before you start peginterferon alfa-2a and each time you get a refill, read any printed information that comes with your medicine.

How Should Peginterferon Alfa-2a Be Stored?

  • Store peginterferon alfa-2a single use vials, prefilled syringes, and autoinjectors in the refrigerator, between 36°F and 46°F (2°C to 8°C). Do not leave peginterferon alfa-2a out of the refrigerator for more than 24 hours.
  • Do not freeze or shake peginterferon alfa-2a.
  • Protect peginterferon alfa-2a from light.
  • Vials, prefilled syringes, and autoinjectors are for single use only. Discard any unused portion remaining in the vial or prefilled syringe.
  • Throw away peginterferon alfa-2a that is no longer needed or expired (out of date). Follow FDA guidelines  on how to safely dispose of unused medicine.
  • Keep peginterferon alfa-2a and all medicines out of reach of children.

Where Can I Find More Information About Peginterferon Alfa-2a?

More information about peginterferon alfa-2a is available:

The above Patient Version drug summary is based on the following FDA label(s): Injection (solution), kit.

[Note from This article was originally published by AIDSinfo on Aug. 28, 2017. We have cross-posted it with their permission.]

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This article was provided by AIDSinfo. Visit the AIDSinfo website to find out more about their activities and publications.

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