Plegridy

Generic name: peginterferon beta-1a [ peg-in-ter-FEAR-on-BAY-ta-- 1A ]
Drug class: Interferons

Medically reviewed by Judith Stewart, BPharm. Last updated on Apr 29, 2024.

What is Plegridy?

Plegridy is made from human proteins. Interferons stimulate the body's immune responses to infection or disease.

Plegridy is used to treat relapsing forms of multiple sclerosis (MS) (including clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease) in adults who are 18 to 65 years old.

Plegridy will not cure multiple sclerosis, it will only decrease the frequency of relapse symptoms.

Plegridy is available in a single-dose prefilled pen or a single-dose prefilled syringe.

Warnings

Plegridy can cause serious side effects, including:

• Liver problems or worsening of liver problems, including liver failure and death. Symptoms may include: yellowing of your skin or the white part of your eye, nausea, loss of appetite, tiredness, bleeding more easily than normal, confusion, sleepiness, dark colored urine, and pale stools.
• During your treatment, you will need to see your healthcare provider and have regular blood tests to check for these possible side effects.
• Depression or suicidal thoughts. Symptoms may include: new or worsening depression (feeling hopeless or bad about yourself), thoughts of hurting yourself or suicide, irritability (getting upset easily), nervousness, or new or worsening anxiety.

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

Before taking this medicine

You should not use Plegridy if you are allergic to peginterferon beta-1a.

To make sure Plegridy is safe for you, tell your doctor if you have:

• depression, mental illness, or suicidal thoughts or actions;

• liver disease;

• bleeding problems;

• an allergy to latex (if you use the prefilled syringe);

• low blood cell counts;

• heart disease;

• a thyroid disorder;

• a seizure; or

• an autoimmune disorder such as rheumatoid arthritis, lupus, or psoriasis.

Some people have thoughts about suicide while using Plegridy. Stay alert to changes in your mood or symptoms.

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

If you are pregnant, your name may be listed on a pregnancy registry to track the effects of peginterferon beta-1a on the baby.

It may not be safe to breastfeed while using Plegridy. Ask your doctor about any risk.

Plegridy is not approved for use by anyone younger than 18 or older than 65 years old.

How is Plegridy given?

Plegridy is usually given once every 2 weeks. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

Plegridy is injected under the skin or into a muscle, usually given once every 2 weeks. A healthcare provider may teach you how to properly use the medication by yourself.

Read and carefully follow any Instructions for Use provided with your Plegridy pen or syringe. Ask your doctor or pharmacist if you don't understand all instructions.

Prepare an injection only when you are ready to give it. Do not use if the medicine has changed colors or has particles in it. Call your pharmacist for new medicine.

Your healthcare provider will show you where on your body to inject Plegridy. Use a different place each time you give an injection. Do not inject into the same place two times in a row.

About 2 hours after your injection, check for skin redness, swelling, or pain where you gave the injection. Call your doctor if you have a skin reaction that does not go away within a few days.

Plegridy can cause flu-like symptoms. Your doctor may recommend taking a pain reliever or fever reducer such as aspirin, acetaminophen (Tylenol), or ibuprofen (Advil, Motrin) on the days you receive your injections.

You will need frequent medical tests.

Store this medicine in the original container in the refrigerator, protected from light.

About 30 minutes before your injection, take the syringe or pen out of the refrigerator and allow it to reach room temperature. Do not warm the medicine under hot water.

You can also store Plegridy for a short time at cool room temperature protected from light. Do not leave the medicine out of a refrigerator for longer than a total of 30 days, including all times it has been taken out of and put back into a refrigerator.

Do not freeze Plegridy, and throw away the medicine if it has become frozen.

Each prefilled syringe or injection pen is for one use only. Throw it away after one use, even if there is still medicine left inside.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

Dosing information

Usual Adult Dose of Plegridy for Multiple Sclerosis:

Initial dose: 63 mcg injected subcutaneously or intramuscularly on day 1, 94 mcg on day 15 (14 days later), reaching the full dose of 125 mcg on day 29 (after another 14 days)
Maintenance dose:125 mcg injected subcutaneously or intramuscularly every 14 days

Comments:
-Patient should be advised to rotate sites for subcutaneous or intramuscular injections. The usual sites for subcutaneous injections are abdomen, back of the upper arm, and thigh. The usual site for intramuscular injections is the thigh.
-Prophylactic and concurrent use of analgesics and/or antipyretics may prevent or reduce flu-like symptoms sometimes experienced during treatment.

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using Plegridy?

Avoid injecting this medicine into skin that is red, bruised, irritated, scarred, or infected.

Plegridy side effects

Get emergency medical help if you have signs of an allergic reaction to Plegridy : hives, itching, bumps on your skin; feeling anxious or light-headed; difficult breathing; swelling of your face, lips, tongue, or throat.

Peginterferon beta-1a can cause life-threatening blood clots in the small blood vessels inside your organs, such as your brain or kidneys. Seek medical help right away if you have symptoms of this condition, such as a fever, tiredness, decreased urination, bruising, or nosebleeds.

Call your doctor at once if you have:

• ongoing pain, swelling, or skin changes where the injection was given;

• a light-headed feeling, like you might pass out;

• unusual changes in mood or behavior (feeling hopeless, anxious, nervous, irritable, or depressed);

• thoughts about suicide or hurting yourself;

• a seizure;

• heart problems - swelling, rapid weight gain, feeling short of breath, rapid heartbeats, chest pain spreading to your jaw or shoulder, nausea, sweating;

• low blood cell counts - fever, chills, tiredness, mouth sores, skin sores, easy bruising, unusual bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath;

• liver problems - nausea, loss of appetite, tiredness, confusion, easy bruising or bleeding, dark urine, clay-colored stools, or jaundice (yellowing of your skin or eyes); or

• thyroid problems - mood swings, trouble sleeping, tiredness, hunger, diarrhea, pounding heartbeats, muscle weakness, sweating, dry skin, thinning hair, menstrual changes, weight changes, puffiness in your face, feeling more sensitive to hot or cold temperatures.

Common Plegridy side effects may include:

• pain, redness, itching, or swelling where the injection was given; or

• flu symptoms - headache, fever, chills, tiredness, body aches.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

What other drugs will affect Plegridy?

Other drugs may interact with peginterferon beta-1a, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

Plegridy Biosimilars

Biosimilar and interchangeable products are biological products that are highly similar to and have no clinically meaningful differences from the reference product.

Reference products

These are biological products that have already been approved by the FDA, against which biosimilar products are compared. There is 1 for Plegridy.

Frequently asked questions

• What are the new drugs used for multiple sclerosis (MS)?
• What is Plegridy used for and is it an immunosuppressant?
• How do you use the Plegridy pen and where do you inject?

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Plegridy can cause serious side effects, including:

• Liver problems or worsening of liver problems, including liver failure and death. Symptoms may include: yellowing of your skin or the white part of your eye, nausea, loss of appetite, tiredness, bleeding more easily than normal, confusion, sleepiness, dark colored urine, and pale stools.
• During your treatment, you will need to see your healthcare provider and have regular blood tests to check for these possible side effects.
• Depression or suicidal thoughts. Symptoms may include: new or worsening depression (feeling hopeless or bad about yourself), thoughts of hurting yourself or suicide, irritability (getting upset easily), nervousness, or new or worsening anxiety.

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

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