Enspryng (satralizumab-mwge) is a prescription drug that’s used to treat a certain condition that affects the nervous system. Enspryng comes as a liquid solution that you inject under your skin.

Specifically, Enspryng is used in certain adults to treat neuromyelitis optica (NMO) spectrum disorder.

To learn more about Enspryng’s uses, see the “Uses for Enspryng” section.

Enspryng basics

Enspryng contains the active ingredient satralizumab-mwge.

Enspryng is a biologic medication. A biologic is made from parts of living organisms. It’s available as a brand-name drug. It isn’t available in a biosimilar form.

Biosimilars are like generic drugs. Just as generic drugs can be an alternative to brand-name medications, biosimilars are an effective alternative to biologics.

Biosimilars will have the same active ingredient core name as the brand-name drug but with unique suffixes. This is why “-mwge” appears at the end of the name of the active ingredient. This is to show it’s distinct from biosimilars that may be created in the future.

Enspryng is used to treat NMO spectrum disorder. Doctors prescribe the drug for adults with a specific immune system protein, known as anti-aquaporin-4 (AQP4).

NMO spectrum disorder is an autoimmune condition that affects the central nervous system. With this condition, the immune system attacks nerve cells in the eyes and spinal cord. It may cause symptoms such as eye pain, vision loss, and numbness or weakness in the arms or legs.

It’s not fully known how Enspryng works to treat NMO spectrum disorder. However, it’s thought that the drug helps reduce inflammation, which may help ease symptoms of the disorder.

Like most drugs, Enspryng may cause mild to serious side effects. The following lists contain some of the more common side effects Enspryng may cause, but they don’t include all possible side effects.

Keep in mind that side effects of a drug can depend on:

  • your age
  • other health conditions you have
  • other medications you take

Your doctor or pharmacist can tell you more about the potential side effects of Enspryng. They can also suggest ways to help reduce side effects.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medications safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect during Enspryng treatment and want to tell the FDA about it, visit MedWatch or call 800-FDA-1088.

Mild side effects

The following is a list of some of the mild side effects that Enspryng can cause. To learn about other mild side effects, talk with your doctor or pharmacist, or read Enspryng’s prescribing information.

Mild side effects of Enspryng that have been reported include:

Mild side effects of many drugs may go away within a few days to a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

Serious side effects

Serious side effects from Enspryng can occur, but they aren’t common. If you have serious side effects from Enspryng, call your doctor right away. If you think you’re having a medical emergency, you should call 911 or your local emergency number.

Serious side effects of Enspryng that have been reported include:

Allergic reaction

For some people, Enspryng can cause an allergic reaction. But it’s not clear whether this side effect occurred in the drug’s studies.

In general, symptoms of an allergic reaction can be mild or serious.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should continue Enspryng treatment.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Enspryng, they may have you switch to a different treatment.

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Form and strength

Enspryng comes as a liquid solution that’s given as an injection under your skin. It’s available in one strength of 120 milligrams per milliliter (mg/mL) of solution.

Recommended dosage

Your doctor will prescribe the dosage of Enspryng that’s right for you. Keep reading to learn more.

Dosage for neuromyelitis optica spectrum disorder

For treating NMO spectrum disorder, your doctor will likely prescribe 1 injection (120 mg) every 2 weeks for the first three doses. After that, you’ll administer 1 injection (120 mg) of Enspryng every 4 weeks for ongoing treatment.

How to inject

Your doctor or another healthcare professional will show you or a caregiver how to inject Enspryng under the skin of your abdomen or thigh. They’ll also explain how much to inject and how often to inject it. Be sure to follow your doctor’s instructions.

To learn more about injecting Enspryng, talk with your doctor. The drug manufacturer also provides step-by-step instructions.

About using Enspryng

The following are some common questions about using Enspryng.

  • What if I miss a dose of Enspryng? What you’ll do for a missed dose of Enspryng depends on the amount of time since your last injection. If you miss a dose of Enspryng, talk with your doctor about next steps.
  • Will I need to use Enspryng long term? Enspryng is typically used as a long-term treatment. If you and your doctor determine that it’s safe and effective for your condition, you’ll likely use it long term.

Enspryng isn’t known to interact with other medications, herbs, supplements, foods, or alcohol. The manufacturer of Enspryng didn’t look at interactions in studies of the drug.

However, it may not be safe to receive certain vaccines during Enspryng treatment.

Before starting Enspryng treatment, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also, tell them about any vitamins, herbs, or supplements you take. Sharing this information can help you avoid potential interactions.

If you have questions about interactions that may affect you, talk with your doctor or pharmacist.

Vaccine interactions

It may not be safe to receive live vaccines during your Enspryng treatment. Live vaccines contain weakened versions of the bacteria or virus that they’re meant to defend against.

Getting a live vaccine during Enspryng treatment may increase your risk of infection. Examples of live vaccines include:

Before starting Enspryng, talk with your doctor about any vaccines you may need. They can help you decide whether to get vaccinated first and whether to delay the start of your Enspryng treatment if needed.

Whether you have health insurance or not, cost may be a factor when you’re considering Enspryng. What you’ll pay for Enspryng may depend on several things, such as your treatment plan and the pharmacy you use.

Here are a few things to consider regarding cost:

  • Cost information and savings coupons: You can visit Optum Perks for price estimates of Enspryng. These estimates are based on the use of Optum Perks coupons. (Note: Optum Perks coupons cannot be used with insurance copays or benefits.)
  • Savings program: If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. Financial assistance programs may also be available.

Optum Perks is owned by RVO Health. By clicking on this link, we may receive a commission. Learn more.

The following is important information to consider and discuss with your doctor or pharmacist before starting Enspryng treatment.

Pregnancy and Enspryng

It’s not known whether Enspryng is safe to start during pregnancy. If you’re planning a pregnancy or can become pregnant, talk with your doctor before starting Enspryng treatment.

If you become pregnant during Enspryng treatment, tell your doctor right away. They may advise you to enroll in the drug’s pregnancy registry, which monitors the safety of Enspryng use during pregnancy.

To learn more about the pregnancy registry, you can talk with your doctor, visit the registry website, or call 833-277-9338.

Enspryng and breastfeeding

It’s not known whether Enspryng should be started while breastfeeding. If you’re currently breastfeeding or planning to do so, talk with your doctor before starting Enspryng treatment.

Before starting Enspryng treatment, discuss your health history with your doctor. Enspryng may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

Note: For more information about the potential negative effects of Enspryng, see the “Side effects of Enspryng” section.

Other drugs are available that can treat NMO spectrum disorder. If you’d like to explore an alternative to Enspryng, talk with your doctor. They can tell you about other medications that might work well for you.

The following drugs are similar to Enspryng:

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.