Interferon alfa-2a

Interferon alfa-2a is a prescription medication used in the treatment of hepatitis C (liver disease caused by the hepatitis C virus). Interferon alfa-2a is also used to treat certain types of leukemia (cancer of the white blood cells).

Interferon alfa-2a belongs to a group of drugs called interferons. Interferons work by fighting viruses in the body, and regulating the production of cells.

This medication comes in single-use, pre-filled syringes. It is injected just under the skin, sometimes daily, or 3 times a week.

Common side effects include flu-like symptoms, extreme tiredness, and upset stomach.

Interferon alfa-2a is a prescription medication used to treat Hepatitis C, hairy cell leukemia, and Philadelphia chromosome positive chronic myelogenous leukemia (CML).

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

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

• Roferon-A

Possible, serious side effects include:

• Mental health problems including suicide, suicidal thoughts, heart problems, and blood problems: See the section "Drug Precautions".
• Other body organ problems: Some patients may experience lung problems (such as difficulty breathing or pneumonia) and vision problems.
• New or worsening autoimmune disease: Some patients may develop an autoimmune disease (a disease where the body's own immune system begins to attack itself) while on interferon alfa-2a therapy. These diseases can include vasculitis (an inflammation of your blood vessels), rheumatoid arthritis or lupus erythematosus, psoriasis or thyroid problems. In some patients who already have an autoimmune disease, the disease may worsen while on interferon alfa-2a therapy.

Common, but less serious, side effects include:

• Flu-like symptoms: Most patients who take interferon alfa-2a have flu-like symptoms that usually lessen after the first few weeks of treatment. Flu-like symptoms may include unusual tiredness, fever, chills, muscle aches, and joint pain. Taking acetaminophen or ibuprofen before you take interferon alfa-2a can help with these symptoms. You can also try taking interferon alfa-2a at night. You may be able to sleep through the symptoms.
• Extreme fatigue (tiredness): Many patients may become extremely tired while on interferon alfa-2a therapy.
• Upset stomach: Nausea, taste changes, diarrhea, and loss of appetite occur commonly.
• Blood sugar problems: Some patients may develop a problem with the way their body controls their blood sugar and may develop diabetes.
• Thyroid problems: Some patients may develop changes in their thyroid function. Symptoms of these changes may include feeling hot or cold all the time, trouble concentrating, changes in your skin (your skin may become very dry), and changes in your weight.
• Skin reactions: Some patients may develop a rash, dry or itchy skin, and redness and swelling at the site of injection.
• Sleep disturbances and headache: Trouble sleeping and headaches may also occur during interferon alfa-2a therapy.
• Hair thinning: Hair loss is not uncommon while using interferon alfa-2a. This hair loss is temporary and hair growth should return after you stop taking interferon alfa-2a.

These are not all of the side effects of interferon alfa-2a. Your doctor or pharmacist can give you a more complete list.

Talk to your healthcare provider if you are worried about side effects or find them very bothersome.

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• barbiturates (such as phenobarbital)
• colchicine
• drugs that may affect your immune system (such as cancer chemotherapy, aldesleukin, cyclosporine)
• hydroxyurea
• stavudine
• telbivudine
• theophyllines (such as aminophylline, theophylline)
• zidovudine

This is not a complete list of interferon alfa-2a drug interactions. Ask your doctor or pharmacist for more information.

The most serious possible side effects of interferon alfa-2a treatment include:

1. Mental health problems: Interferon alfa-2a may cause some patients to develop mood or behavioral problems. Signs of these problems include irritability (getting easily upset), depression (feeling low, feeling bad about yourself or feeling hopeless), and anxiety. Some patients may have aggressive behavior and think about hurting others. Some patients may develop thoughts about ending their lives (suicidal thoughts) and may attempt to do so. A few patients have even ended their lives. Former drug addicts may fall back into drug addiction or overdose. You must tell your healthcare provider if you are being treated for a mental illness or have a history of mental illness or if you are or have ever been addicted to drugs or alcohol. Call your healthcare provider immediately if you develop any of these problems while on interferon alfa-2a treatment.
2. Heart problems: Interferon alfa-2a may cause some patients to experience high blood pressure, a fast heartbeat, chest pain, and very rarely a heart attack. Tell your healthcare provider if you have or have had any heart problems in the past.
3. Blood problems: Many patients taking interferon alfa-2a have had a drop in the number of their white blood cells and their platelets. If the numbers of these blood cells are too low, you could be at risk for infections or bleeding.

Stop taking interferon alfa-2a and call your healthcare provider immediately if you develop any of these symptoms:

• You become very depressed or think about suicide
• You have severe chest pain
• You have trouble breathing
• You have a change in your vision
• You notice unusual bleeding or bruising
• High fever
• Severe stomach pain. If the pain is in the lower part of your stomach area it could mean that your bowels are inflamed (colitis)

Do not use interferon alfa-2a if:

• You are pregnant or breastfeeding or are planning to become pregnant.
• You are allergic to alpha interferons, Escherichia coli-derived products or any component of interferon alfa-2a.
• You have autoimmune hepatitis (hepatitis caused by your immune system attacking your liver).

Interferon alfa-2a should not be given to newborn or premature infants.

Medications 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 interferon alfa-2a, there are no specific foods that you must exclude from your diet when receiving this medication.

If you have or have had any of the following conditions or serious medical problems, discuss them with your doctor before taking interferon alfa-2a:

• History of or current severe mental illness (such as depression or anxiety)
• Previous heart attack or heart problems
• Sleep problems
• High blood pressure
• Autoimmune disease (where the body's immune system attacks the body's own cells), such as vasculitis, psoriasis, systemic lupus erythematosus, rheumatoid arthritis
• Kidney problems
• Blood disorders-Low blood counts or bleeding problems
• You take a medicine called theophylline
• Diabetes (high blood sugar)
• Thyroid problems
• Liver problems, other than hepatitis C
• Hepatitis B infection
• HIV infection (the virus that causes AIDS)
• Problems with your vision
• Colitis
• Body organ transplant and are taking medicine that keeps your body from rejecting your transplant (suppresses your immune system)
• Alcoholism
• Drug abuse or addiction

If you have any doubts about your health condition or about taking interferon alfa-2a, talk to your healthcare provider.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Interferon alfa-2a falls into category C. In animal studies, pregnant animals were given this medication and had some babies born with problems. No well-controlled studies have been done in humans.

• Female patients as well as female partners of male patients must avoid becoming pregnant while taking interferon alfa-2a. This medication may harm your unborn child or cause you to lose your baby (miscarry).

It is not known if interferon alfa-2a crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication. Your doctor and you will decide if the benefits outweigh the risk of using interferon alfa-2a.

To get the most benefit from this medicine, it is important to take interferon alfa-2a exactly as your healthcare provider tells you.

Your healthcare provider will tell you how much medicine to take and how often to take it. Once you start treatment with interferon alfa-2a, do not switch to another brand of interferon without talking to your doctor. Other interferons may not have the same effect on the treatment of your disease. Switching brands will also require a change in your dose. Your healthcare provider will tell you how long you need to use interferon alfa-2a.

Over time, your healthcare provider may change your dose of interferon alfa-2a. Do not change your dose unless your doctor tells you to change it.

Interferon alfa-2a is supplied in prefilled syringes.

If you miss a dose of interferon alfa-2a, take the missed dose as soon as possible during the same day or the next day, then continue on your regular dosing schedule. If several days go by after you miss a dose, check with your doctor about what to do. Do not double the next dose or take more than one dose a day unless your doctor tells you to. Call your doctor right away if you take more than your prescribed interferon alfa-2a dose. Your doctor may wish to examine you more closely and take blood for testing.

You must get regular blood tests to help your healthcare provider check how the treatment is working and to check for side effects.

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dose your doctor recommends may be based on the following:

• the condition being treated
• other medical conditions you have
• other medications you are taking
• how you respond to this medication
• your weight
• your height
• your age
• your gender

• The recommended dosage for the treatment of chronic hepatitis C is 3 million international units (MIU) three times a week (tiw) for 12 months (48 to 52 weeks).
• A recommended alternative dose for chronic hepatitis C is 6 MIU tiw for the first 3 months (12 weeks) followed by 3 MIU tiw for 9 months (36 weeks).
  • Re-treatment with either 3 MIU tiw or with 6 MIU tiw for 6 to 12 months may be considered based on response to the medication.
• The recommended starting dose for chronic myelogenous leukemia is 9 MIU daily. The target doseisf 9 MIU daily for the duration of the treatment period.
• The induction dose for hairy cell leukemia is 3 MIU daily for 16 to 24 weeks. The recommended maintenance dose is 3 MIU tiw.

Call your doctor right away if you take more than your prescribed interferon alfa-2a dose.

• Interferon alfa-2a must be stored in the refrigerator at a temperature of 36°F to 46°F (2°C to 8°C).
• Do not leave interferon alfa-2a outside of the refrigerator for more than 24 hours.
• Do not freeze interferon alfa-2a. Keeping interferon alfa-2a at temperatures outside the recommended range can destroy the medicine.
• Do not shake interferon alfa-2a. Shaking can destroy interferon alfa-2a so that it will not work.
• Protect interferon alfa-2a from light during storage.

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