Interferons are lab-made proteins that lower inflammation in your body. They treat relapsing MS (RMS) by changing the balance of chemical messengers that regulate cell growth and activity called cytokines. Researchers haven’t figured out the exact process interferons go through to lower inflammation, but lower levels of cytokines results in less inflammation.
How Do Interferons Work?
Although experts don’t know the exact method, they know that interferons dampen the inflammation MS causes. Scientists make interferons in a lab to mimic the action of proteins that you already have in your body. Through the action of these interferons, inflammation goes down and you have less damage to the cells that make up your myelin sheath.
What Interferons Are Used to Treat Relapsing MS?
Interferons doctors prescribe to treat RMS include:
- Interferon beta-1a (Avonex, Rebif)
- Interferon beta-1b (Betaseron, Extavia)
- Peginterferon beta-1a (Plegridy)
Peginterferon beta-1a is a “pegylated" form of interferon. Pegylated forms of interferon have a polyethylene glycol attached to the interferon molecules. This extends their effect in the body for longer, which means you take doses of the medication less often.
When Are Interferons Prescribed for Relapsing MS?
Doctors recommend interferons to treat active RMS. For your MS to be active, you have to have had two or more relapses in the last two years.
You can take interferons if:
- You have relapsing MS and you've had a recent relapse and/or if MRI scans show new signs that your MS is active (you have new lesions).
- You have a clinically isolated syndrome (CIS), a first attack of MS-like symptoms and a brain scan shows you're likely to go on to get MS.
How Do You Take Interferons?
Interferons are injections you give yourself either into the skin or into a muscle. You give yourself the injection at home using an injector pen – a device with a small, thin needle.
How Effective Are Interferons?
Not everyone responds to interferon treatments. In fact, as many as 50% may not see a change in their disease while taking them. Still, they can work for some people. Long-term use of interferons, for some, can produce neuroprotective proteins and even increase survival rates in MS.
Experts use annualized relapse rate (ARR) in clinical trials to track the number of relapses in people living with MS. For those who had improvement with interferons in clinical trials, all forms of the drug were nearly equal in how well they reduced relapses and the number of lesions.
Are Interferons Safe?
Among all the disease-modifying treatments, interferons have some of the fewest side effects. There are a few precautions you should take if you decide to take them.
People who live with depression may feel these symptoms get worse. Tell your doctor right away if you are feeling more down than usual or having thoughts of harming or killing yourself.
Interferons lower your body’s natural immunity, so you’re at higher risk of infection.
What Are the Common Side Effects of Interferons?
Side effects of interferons tend to happen during your first weeks of treatment. You may find it helpful to take this medicine at night so you have more energy during the day.
Common side effects of interferons include:
- Fatigue
- Chills
- Fever
- Muscle aches
- Sweating
- Dry eyes
- Vision problems
- Dry mouth
It's also common to have bruising, pain, redness, swelling, or tenderness at the injection site
You may have fewer side effects in general if you take peginterferon beta-1a (Plegridy), since you don’t have to take it as often. For some people, this helps them stick to their treatment plan.
Who Should Not Take Interferons?
Your doctor needs to know if you’re taking levoketoconazole, a medication that treats Cushing’s syndrome, or methotrexate, a medication doctors prescribe for cancer, psoriasis, or rheumatoid arthritis. Doctors don’t recommend taking these medications with interferons. If you can’t avoid it, your doctor may change the dose or how often you use one or both of the medicines.
Your doctor will also want to know if you have:
- Blood or bone marrow problems such as anemia or low white blood cells
- Congestive heart failure
- History of depression
- Liver problems
- Seizures
- Thyroid problems
Using interferons can make these conditions worse.
How Much Do Interferons Cost?
Like many disease-modifying drugs for MS, interferons can be expensive. The retail price for each drug ranges from $7,000 to $11,000. It’s unlikely you’d pay this entire cost. There are ways to reduce the expense:
Check your coverage. You may need a health insurance plan that has different coverage than the one you’re on. Even if your monthly premium increases, it may save you money over time if it lowers treatment costs.
Tap into organizations. Nonprofit organizations like The Assistance Fund, Good Days, and HealthWell Foundation often help with costs like copays.
Search for coupons. The manufacturers of certain interferons offer assistance programs or coupons for their treatments. These include:
- Interferon beta-1a (Avonex)
- Interferon beta-1a (Rebif)
- Interferon beta-1b (Betaseron)
- Peginterferon beta-1a (Plegridy)
Extavia doesn't offer an assistance program.
Clinical Trials of Interferons for Relapsing MS
MS research benefits greatly from people volunteering to be part of clinical trials. Studies are always ongoing – not just on disease-modifying therapies like interferons, but on devices, lifestyle modifications, and other ways to improve the lives of people with MS.
Researchers monitor the people in these studies closely to make sure they’re safe.
If you’re considering taking part in a clinical trial, you’ll want to think through the pros and cons. On the plus side, you’ll:
- Take an active role in your health care
- Get access to new research treatments before they’re available everywhere
- Treatments may be at low or no cost to you
- Help others and contributing to medical research
There are some risks, too.
- You could have serious or even life-threatening side effects from any treatment you try.
- The treatment you take in the study may not work at all.
- You may get the placebo (sugar pill) instead of active medication.
- It often means extra time out of your schedule for extra tests or doctor’s visits.
- Some costs may not be covered by insurance.
Your doctor is a good place to start if you’re interested in a clinical trial. You’ll have to qualify in order to take part. Your doctor may know of studies you’d be a fit for. You can also look on ClinicalTrials.gov to search the database for all clinical studies in the country.
What to Know if You’re a Caregiver
As a caregiver for someone living with MS, you may be an intimate part of their treatment decision-making process. Be sure you understand what’s involved with their choice. If you’re able to go to doctor’s appointments with them, you can learn more about what’s in store and even ask your own questions.
If they choose an interferon, you may help give them their dose. You’ll need to learn how to use the injector pen and know what the dosing schedule is.
Is an Interferon Right for Me?
Deciding on a treatment for your relapsing MS is an important decision. Go over these points yourself and with your doctor as you make your choice.
How you’ll take it
Interferons are injected medications. In most cases, you’ll learn how to do these injections yourself, and then you (or a loved one) will be responsible for delivering your dose. It may help you to see what an injector pen looks like in person. Ask your doctor if you can have a demonstration or see a sample in their office.
Other health conditions
You and your doctor will go over your medical and family health history as part of your treatment conversations. Blood or bone marrow problems such as anemia or low white blood cells, congestive heart failure, depression, liver issues, history of seizures, and thyroid problems can also be a barrier to choosing interferons as your MS treatment.
Costs
Like most DMTs for MS, interferons are pricey, but you have options for financial assistance. Do your research with your health insurance company before you lock in a treatment so you know what your expected costs will be. Find out if your treatment of choice offers a manufacturer's coupon. Interferon beta-1b (Extavia) does not offer financial assistance, but other interferons do.
Prior treatments
If you’ve already tried an MS treatment that didn’t work for you, it can help you learn about what may work in the future. Also, if you take medication for Cushing’s disease or are on methotrexate, your doctor may recommend you try a different MS treatment or might want to change your other treatment.
Potential side effects
On the whole, interferons come with fairly mild side effects, but everyone reacts differently to different medications. Pay attention to how you’re feeling as you begin a treatment and take note if you have unusual symptoms. Based on how interferons typically act in most people, it’s common to have flu-like symptoms.