Information for Healthcare Providers / Patients

Pegasys® (peginterferon alfa-2a)

Side Effect Reporting

You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/medwatch.

You may also report side effects to Genentech at (888) 835-2555.

What it Treats

What is PEGASYS?

PEGASYS® (peginterferon alfa-2a) is a prescription medication that is:

  • used with other hepatitis C medicines to treat adults with chronic (lasting a long time) hepatitis C and certain types of liver problems
  • used with a hepatitis C medicine called ribavirin to treat adults and children 5 years and older with chronic hepatitis C and certain types of liver problems
  • used alone to treat chronic hepatitis C only if you are not able to take other hepatitis C medicines
  • not recommended to be used alone or with a hepatitis C medicine called ribavirin without additional hepatitis C medicines if you have taken an alpha interferon
  • not recommended to treat chronic hepatitis C if you have had a solid organ transplant
  • used to treat adults with chronic hepatitis B virus who show signs that the virus is damaging the liver

It is not known if PEGASYS is safe and will work in children under 5 years of age.

Important Safety Information

PEGASYS, like other alpha interferons, may cause or make fatal or life-threatening problems worse (like mental, immune system, heart, liver, lung, intestinal and infections). A patient’s doctor should monitor the patient during regular visits. If patients show signs or symptoms of these conditions, their doctor may stop their medication. In many patients, but not all, these conditions get better after they stop taking PEGASYS (see the Medication Guide for more information and Warnings).

The most important information I should know about PEGASYS is:

  • Ribavirin in combination with PEGASYS may cause birth defects or death of a patient’s unborn baby
  • PEGASYS therapy may cause patients to develop mood or behavioral problems
  • Some people who take PEGASYS alone or in combination with ribavirin may get heart problems
  • Stroke or symptoms of a stroke.
  • Some people taking PEGASYS develop new or worsening autoimmune problems
  • Some people who take PEGASYS may get an infection.

PEGASYS alone or in combination with ribavirin can cause serious side effects. Some of these side effects may cause death. Patients must tell their healthcare provider right away if they have any of these symptoms while taking PEGASYS.

Patients must not take PEGASYS if they:

  • have certain other liver problems
  • have certain types of hepatitis caused by their immune system attacking the liver (autoimmune hepatitis)
  • have had a serious allergic reaction to another alpha interferon medicine or to any of the ingredients in PEGASYS

Patients must not take PEGASYS in combination with ribavirin if they:

  • are pregnant, or planning to get pregnant during treatment or during the 6 months after treatment
  • are a male patient with a female sexual partner who is pregnant or plans to become pregnant at any time while they are being treated with ribavirin or during the 6 months after their treatment has ended

PEGASYS cannot be given to a baby under 1 year of age. PEGASYS contains benzyl alcohol.

Before taking PEGASYS, patients must tell their healthcare provider about all their medical conditions or problems, and if they are pregnant or breastfeeding, or plan to become pregnant or breast feed during treatment with PEGASYS.

Patients must tell their healthcare provider about all the prescription and non-prescription medicines, vitamins and herbal supplements they take.

PEGASYS can cause serious side effects including: blood problems, thyroid problems, blood sugar problems, serious eye problems, serious liver problems, worsening of liver problems including liver failure and death, lung problems, inflammation of the pancreas, inflammation of the intestines, serious allergic reactions and skin reactions, effect on growth in children, and nerve problems.

The most common, but less serious, side effects of PEGASYS include: flu-like symptoms, tiredness and weakness, stomach problems, loss of appetite, skin reactions, hair thinning, trouble sleeping.

Patients must tell their healthcare provider if they have any side effect that bothers them or that does not go away.

Report side effects to the FDA at (800) FDA-1088 or www.fda.gov/medwatch.
Patients and caregivers may also report side effects to Genentech at (888) 835-2555.

Please see the PEGASYS full Prescribing Information and Medication Guide, including Boxed WARNINGS, for additional Important Safety Information.

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