Peginterferon alfa-2a

Peginterferon alfa-2a is a prescription medication used to treat hepatitis B and also to treat chronic (lasting a long time) hepatitis C infection in people who have not taken alpha interferon.  Peginterferon alfa-2a belongs to a group of drugs called interferons. It works by activating the body's immune system to attack hepatitis viruses.

This medication comes in an injectable form in a prefilled syringe and is given just under the skin. It is usually given once a week, for up to 48 weeks.

Common side effects of peginterferon alfa-2a are flu-like symptoms, tiredness, and stomach problems.

Peginterferon alfa-2a is a prescription medicine used to treat

• hepatitis B
• chronic (lasting a long time) hepatitis C infection, with or without the medication ribavirin, in people who have not yet taken alpha interferon

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Peginterferon alfa-2a may be found in some form under the following brand names:

• Pegasys

Peginterferon alfa-2a can cause serious side effects including:

1. Blood problems. Peginterferon alfa-2a can affect your bone marrow and cause low red blood cell, low white blood cell and platelet counts. In some people, these blood counts may fall to dangerously low levels. If your blood cell counts become very low, you can get anemia, infections or have problems with bleeding and bruising.

2. Thyroid problems. Some people develop changes in the function of their thyroid. Symptoms of thyroid changes include feeling cold or hot all the time, a change in your weight, and changes to your skin, trouble concentrating.

3. Blood sugar problems. Some people may develop high blood sugar or diabetes. If you have high blood sugar or diabetes before starting peginterferon alfa-2a, talk to your healthcare provider before you take peginterferon alfa-2a. If you develop high blood sugar or diabetes while taking peginterferon alfa-2a, your healthcare provider may tell you to stop peginterferon alfa-2a and prescribe a different medicine for you.

Symptoms of high blood sugar or diabetes may include:

• Increased thirst
• Tiredness
• Urinating more often than normal
• Increased appetite
• Weight loss
• Your breath smells like fruit

4. Serious eye problems. Peginterferon alfa-2a may cause eye problems that may lead to vision loss or blindness. You should have an eye exam before your start taking peginterferon alfa-2a. If you have eye problems or have had them in the past, you may need eye exams while taking peginterferon alfa-2a. Tell your healthcare provider or eye doctor right away if you have any vision changes while taking peginterferon alfa-2a.

5. Serious liver problems, worsening of liver problems, including liver failure and death.

Symptoms of liver problems may include:

• nausea
• loss of appetite
• tiredness
• diarrhea
• yellowing of your skin or the white part of your eyes
• bleeding more easily than normal
• swelling of your stomach area (abdomen)
• confusion
• sleepiness
• you cannot be awakened (coma)

6. Lung problems including:

• trouble breathing
• pneumonia
• inflammation of lung tissue
• new or worse high blood pressure of the lungs (pulmonary hypertension). This can be severe and may lead to death. You may need to have a chest X-ray or other tests if you develop fever, cough, shortness of breath or other symptoms of a lung problem during treatment with peginterferon alfa-2a.

7. Inflammation of your pancreas (pancreatitis). Symptoms of inflammation of your pancreas (pancreatitis) may include:

• severe stomach (abdomen) pain
• severe back pain
• nausea
• vomiting
• fever

8. Inflammation of your intestines (colitis). Symptoms of inflammation of your intestines (colitis) may include:

• severe stomach area (abdomen) pain
• bloody diarrhea or bloody bowel movements

9. Serious allergic reactions and skin reactions. Symptoms may include:

• itching
• swelling of your face, eyes, lips, tongue, or throat
• trouble breathing
• anxiousness
• chest pain
• feeling faint
• skin rash, hives, sores in your mouth, or your skin blisters and peels

10. Nerve problems. People who take peginterferon alfa-2a or other alpha interferon products with telbivudine (Tyzeka) for hepatitis B can develop nerve problems such as continuing numbness, tingling, or burning sensation in the arms or legs (peripheral neuropathy).

11. Effect on growth in children. Children can experience a delay in weight gain and height increase while being treated with peginterferon alfa-2a and ribavirin. Catch-up in growth happens after treatment stops, but some children may not reach the height that they were expected to have before treatment. Talk to your healthcare provider if you are concerned about your child’s growth during treatment with peginterferon alfa-2a and ribavirin.

Call your healthcare provider if you have any of these symptoms. Tell your healthcare provider right away if you have any of the symptoms listed above.


The most common, but less serious side effects of peginterferon alfa-2a include:

• flu-like symptoms. Symptoms may include: fever, chills, muscle aches, joint pain, and headaches. Some of these symptoms may be decreased by injecting your peginterferon alfa-2a dose in the evening. Talk to your healthcare provider about which over-the-counter medicines you can take to help prevent or decrease some of the symptoms.
• tiredness and weakness. Many people become very tired or feel weak while taking peginterferon alfa-2a.
• stomach problems. Nausea and vomiting may happen with peginterferon alfa-2a.
• loss of appetite
• skin reactions. Some people may develop redness, swelling, dry or itchy skin at the site of injection. If after several days these symptoms do not disappear, contact your healthcare provider.
• hair thinning. Temporary hair loss is not uncommon during treatment with peginterferon alfa-2a.
• trouble sleeping

Tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins and herbal supplements. Peginterferon alfa-2a and certain other medicines may affect each other and cause side effects. Especially tell your healthcare provider if you take:

• the anti-hepatitis B medicine telbivudine (Tyzeka).
• theophylline (Theo-24, Elixophyllin, Uniphyl, Theolair). Your healthcare provider may need to monitor the amount of theophylline in your body and make changes to your theophylline dose.
• any anti-HIV medicines
• methadone hydrochloride (Methadose, Dolophine hydrochloride)
• azathioprine (Azasan, Imuran)

Know the medicines you take. Keep a list of them and show it to your healthcare provider and pharmacist when you get a new medicine.

Do not take peginterferon alfa-2a in combination with ribavirin if you:

• 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 you are being treated with ribavirin or during the 6 months after your treatment has ended
• have certain blood disorders such as thalassemia major or sickle-cell anemia.
• take didanosine (Videx or Videx EC)

Do not take peginterferon alfa-2a if you:

• have certain other liver problems
• have certain types of hepatitis caused by your immune system attacking your liver (autoimmune hepatitis)
• have had a serious allergic reaction to another alpha interferon medicine or to any of the ingredients in peginterferon alfa-2a. Symptoms of a serious allergic reaction to alpha-interferon may include: itching, swelling of your face, tongue, throat, trouble breathing, feeling dizzy or faint, and chest pain.


• 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 you are being treated with ribavirin or during the 6 months after your treatment has ended
• have certain blood disorders such as thalassemia major or sickle-cell anemia
• take didanosine (Videx or Videx EC)

Do not give peginterferon alfa-2a to a baby under 1 year of age. Peginterferon alfa-2a contains benzyl alcohol. Benzyl alcohol can cause nervous system problems and other problems which may lead to death. 

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of peginterferon alfa-2a there are no specific foods that you must exclude from your diet when receiving peginterferon alfa-2a.

Before taking peginterferon alfa-2a, tell your healthcare provider if you have:

• liver problems (other than hepatitis B or C) or had lung problems
• thyroid problems
• diabetes
• colitis (inflammation of your intestine)
• cancer
• hepatitis B or C infection
• HIV infection (the virus that causes AIDS)
• kidney problems
• high blood triglyceride levels (fat in your blood)
• an organ transplant
• any other medical conditions
• are pregnant or breastfeeding

• If you are pregnant do not start taking or continue taking peginterferon alfa-2a alone or in combination with ribavirin. Ribavirin in combination with peginterferon alfa-2a may cause birth defects or death of your unborn baby.
• Avoid becoming pregnant while taking peginterferon alfa-2a, alone or in combination with ribavirin. Peginterferon alfa-2a, alone or in combination with ribavirin, may harm your unborn child (death or serious birth defects) or cause you to lose your baby (miscarry).

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if peginterferon alfa-2a is excreted in human breast milk or if it will harm your nursing baby.

• Peginterferon alfa-2a is given by injection under the skin (subcutaneous injection).
• Your healthcare provider will decide on your dose of peginterferon alfa-2a and when you will take it. Peginterferon alfa-2a is usually injected one time each week.
• If your healthcare provider decides that you can inject peginterferon alfa-2afor your condition, inject it exactly as prescribed.
• Your healthcare provider may change your dose of peginterferon alfa-2a if needed. Do not change your dose unless your healthcare provider tells you to change it.
• Do not switch to another brand of interferon without talking to your healthcare provider
• Take your prescribed dose of peginterferon alfa-2a1 time each week, on the same day of each week and at approximately the same time.
• Do not take more than your prescribed dose.
• If you miss your dose
• If you remember within 2 days of when you should have taken peginterferon alfa-2a, give yourself an injection of peginterferon alfa-2a as soon as you remember. Take your next dose on the day you would usually take it.
• If more than 2 days have passed, ask your healthcare provider what you should do.
• Your healthcare provider should show you how to prepare and measure your dose of peginterferon alfa-2a, and how to inject yourself before you use peginterferon alfa-2a for the first time.

Take peginterferon alfa-2a exactly as prescribed by your doctor. Follow the directions on your prescription label carefully. Your doctor will determine the best dose for you.

Chronic Hepatitis C with HIV Coinfection

If you take too much peginterferon alfa-2a, call your local Poison Control Center or seek emergency medical attention right away.

• Store peginterferon alfa-2a single use vials and prefilled syringes in a refrigerator, at 36°F to 46°F (2°C to 8°C).
• Do not freeze or shake peginterferon alfa-2a.
• Protect peginterferon alfa-2a from light. Keep peginterferon alfa-2a vials, prefilled syringes, and all medicines out of the reach of children.

WARNING:

Alpha interferons, including peginterferon alfa-2a, may cause or aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. Patients should be monitored closely with periodic clinical and laboratory evaluations. Therapy should be withdrawn in patients with persistently severe or worsening signs or symptoms of these conditions. In many, but not all cases, these disorders resolve after stopping peginterferon alfa-2a therapy.

Use with Ribavirin

Ribavirin, including Copegus, may cause birth defects and/or death of the fetus. Extreme care must be taken to avoid pregnancy in female patients and in female partners of male patients. Ribavirin causes hemolytic anemia. The anemia associated with ribavirin therapy may result in a worsening of cardiac disease.