Your Guide to Enspryng for Neuromyelitis Optica Spectrum Disorder

Medically Reviewed by Ami Ishver, PharmD on February 06, 2025
8 min read

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disorder that mostly affects your eyes and spinal cord. Your immune system attacks a specific protein, called aquaporin-4 (AQP4). The chronic inflammation from these attacks can cause loss of vision and difficulty with mobility. There is no cure for NMOSD. Treatment usually consists of medicines to help reduce inflammation, ease symptoms, and prevent future attacks (relapses). 

Enspryng is a biologic medicine that may help reduce inflammation and prevent relapses of NMOSD, especially if you have anti-AQP4 antibodies in your blood.

Neuromyelitis optica spectrum disorder (NMOSD) is a rare disorder where your immune system attacks healthy cells in the central nervous system (brain and spinal cord). It creates a defective antibody against a protein in your central nervous system, called aquaporin-4 (AQP4). This causes inflammation around the optic nerve (carries messages from your eye to your brain) and spinal cord, which can lead to vision loss, muscle weakness and other symptoms as shown in the table below. 

Table 1. Symptoms of Neuromyelitis Optica Spectrum Disorder

Inflammation of the optic nerve, also called optic neuritis

  • Pain in your eye or when you move your eyes
  • Blurred vision
  • Inability to see colors
  • Blindness in one or both eyes (rare)
  • Flashing or flickering light when you move your eyes

Inflammation of the spinal cord, also called transverse myelitis

  • Pain, weakness, numbness, or paralysis in your arms or legs
  • Bladder or bowel problems
  • Nausea or vomiting
  • Hiccups
  • Stiff neck
  • Headache
  • Daytime sleepiness

Your health care provider will focus on treating your symptoms, reducing inflammation, and preventing relapses with steroids or biologic medicines. However, relapses can still happen despite treatment. Newer medicines focus on preventing relapses by targeting defective antibodies or proteins in your body. Enspryng blocks a protein called interleukin-6 (IL-6). IL-6 plays a role in the inflammation caused by the anti-APQ4 antibodies. By blocking IL-6, Enspryng can help reduce inflammation, improve symptoms, and prevent relapses. 

Enspryng is a medicine that is injected under the skin either into the lower part of your stomach or the front and middle part of your thigh. The first three injections are given every 2 weeks followed by injections every month. It is important to track your injections and stay on a regular schedule. Use a calendar or set a reminder on your phone to help keep the schedule. If you miss an injection, talk to your health care provider about when and how to restart your injections. 

Your health care provider will train you on the correct way to use the injector, the places on your body for the injection, and how to rotate sites for each injection. Always wash your hands before using the injector. The manufacturer has an instructional video that can be found at www.enspryng.com

Keep Enspryng in the refrigerator. Do not freeze or shake the medicine. Allow 30 minutes for the medicine to come to room temperature before giving the injection. Do not warm the medicine in the microwave or under warm water.

Talk with your health care provider about any vaccines that you may need. You should not receive certain vaccines right before or while using Enspryng. Tell your health care provider about any vaccines you have recently received or have scheduled.

Two studies have been done to look at the safety and efficacy of Enspryng for the treatment of neuromyelitis optica spectrum disorder (NMOSD) when compared with placebo. Placebo-controlled studies help researchers see differences in benefit or harm of a medicine when compared with no treatment.

To be included in both studies, people had to have a diagnosis of NMOSD with or without aquaporin-4 (AQP4) antibodies in their blood, evidence of relapses, and an Expanded Disability Status Scale (EDSS) score between 0 and 6.5. The use of EDSS helps to determine the amount of disability caused by the NMOSD symptoms, where 0 is no disability and 6.5 is some limitations in walking. People were assigned to receive either Enspryng injections or placebo. The table below provides more information about the people receiving Enspryng in the studies.

Table 2. Study Participants

 

Study 1

Study 2

Other medicines

Not taking other immune-suppressing medicines

Taking other immune-suppressing medicines like oral corticosteroids, azathioprine, or mycophenolate mofetil

Relapses

At least one in the past year

At least two in the past two years

Average age

44

46

Gender

Female (76%)

Female (100%)

Race or Ethnicity

White (50%)

Black or African American (22%)

Asian (20%)

White (46%)

Asian (52%)

Average EDSS Score

3.8

4.0

Median treatment duration

95.9 weeks

143.1 weeks

Efficacy in the study was based on the time to the first relapse, which was defined as new or worsening neurological symptoms and increase in the EDSS score. Other outcomes included changes to the Visual Analog Scale (VAS) pain score and the Functional Assessment of Chronic Illness Therapy (FACIT) fatigue score. 

  • VAS measures pain based on a 0 to 100 scale, where 0 is no pain and 100 is “pain as bad as it can be.”
  • FACIT fatigue score is based on 13 questions that measures fatigue (tiredness) and asthenia (feeling unusually tired or week).

In both studies, less people in the Enspryng group had a relapse compared with people in the placebo group. This means that Enspryng may reduce your symptoms and how often you have an attack of symptoms. For patients without anti-AQP4 antibodies, there was not a benefit from Enspryng compared with placebo. 

Table 3. Relapse Rates for People with NMOSD and Anti-AQP4 Antibodies

 

Enspryng

Placebo

STUDY 1 – Enspryng alone

  

Relapse

30%

50%

Reduction in risk of relapse

74%

 
   

STUDY 2 – Enspryng with other immune-suppressing medicines

Relapse

20%

43%

Reduction in risk of relapse

78%

 

There was no real difference seen with changes in VAS or FACIT fatigue scores for people taking Enspryng compared with people taking placebo.

Your results may differ from what was seen in clinical studies. You and your health care provider should determine if the benefits outweigh any potential risks. 

After a few months, you may see improvements in the frequency or severity of your symptoms. The long-term goal is to slow progression and prevent relapses, so it is important to track the following symptoms and review with your health care provider. 

  • Vision changes
  • Strength or ability to walk without assistance
  • Numbness or tingling sensations in the hands, feet, arms, and legs

Keep all appointments with your health care provider while you are using Enspryng, even if you don't feel immediate changes in your symptoms. Your health care provider may also monitor your progress through different blood, imaging, or physical tests.

You should not receive Enspryng if you have an allergy to it or any of the ingredients, have an active hepatitis B infection, or have active or untreated tuberculosis. Your health care provider may perform blood tests before starting Enspryng to check for hepatitis B or tuberculosis. 

The most common side effects of Enspryng include infection of the nose and throat, headache, nausea, rash, gastritis, tiredness, and pain in your arms, legs, or joints. Tell your health care provider if you have any of these symptoms. 

Infections. Enspryng can increase the risk of common or serious infections. Tell your health care provider if you are being treated for an infection, or contact them if you have the following signs of an infection: 

  • Chills, feeling tired, aches, fever, sore throat, or a cough that will not go away
  • Skin redness or swelling
  • Diarrhea, stomach pains, or feeling sick
  • Burning when you urinate (pee) or urinating more often

Nausea. Tell your health care provider if you have nausea that is bothersome. They may give you medicine for nausea and give guidance on possible diet changes to help ease the symptoms. Make sure that you stay hydrated, drinking plenty of water.

Gastritis. Gastritis is an inflammation or irritation in the lining of your stomach. Tell your health care provider if you have stomach problems, including trouble digesting, nausea, bloating, stomach pain, or loss of appetite.

Rash. Call your health care provider if you develop a rash while using Enspryng. Get emergency help if this rash spreads to other areas of the body.

These are not all of the possible side effects. Talk with your health care provider if you are having symptoms that bother you. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

Before starting Enspryng, your health care provider may perform blood tests to check the health of your liver or for active hepatitis B, untreated tuberculosis, or other signs of infection. These tests may be repeated during treatment. It is important to keep all appointments for lab work. 

There are no known interactions between Enspryng and food, drinks, or other medicines. Tell your pharmacist or health care provider about all the prescription or OTC medicines, vitamins/minerals, herbal products, or other supplements you take or have recently taken. Contact your health care provider if you believe you are having side effects due to a potential interaction. 

Enspryng is considered a specialty medicine, which is a high-cost medication that is taken for rare, complex, or long-term (chronic) diseases. It requires a different process than picking up your prescription at a local pharmacy. This process helps you stay on track with your treatment. Your health care provider will work with you, your insurance company, and/or the manufacturer to start the process. 

Here are some differences that you may expect. 

Insurance approval. Your insurance may require approval for using this medicine, also called a prior authorization. The insurance company reviews the prescription from your health care provider to make sure it is covered and determines the process that needs to be followed.  

Pharmacy access. You may be required to use a specific pharmacy to get your medicine. Your health care provider will work with you and your insurance company on which pharmacy to use and the information that will be provided. 

Copay assistance. There is a copay assistance program from the manufacturer that may allow you to pay $0 for your prescription. Whether you are eligible depends on whether you have prescription insurance and what type of insurance you have. If you don’t have insurance, there may be assistance based on specific financial criteria. You can find out more at www.enspryng.com/financial-support/assistance-options or by calling 844-677-7964.