Imaavy (Nipocalimab-Aahu) for Myasthenia Gravis

Imaavy (nipocalimab-aahu) is a prescription medication approved by the U.S. Food and Drug Administration (FDA) for treating generalized myasthenia gravis in adults and children ages 12 years and older.

How Imaavy Works and How It’s Taken

Imaavy is a type of medicine called a neonatal Fc receptor (FcRn) blocker. It works by attaching to a protein called FcRn, which lowers levels of immunoglobulin G (IgG), a type of antibody, in the blood. In people with generalized myasthenia gravis, Imaavy lowers certain harmful antibodies called anti-acetylcholine receptor (anti-AChR) and anti-muscle-specific tyrosine kinase (anti-MuSK) autoantibodies. This may help reduce muscle weakness and improve symptoms.

Doctors prescribe Imaavy when a person 12 years or older has generalized myasthenia gravis and tests positive for anti-AChR or anti-MuSK antibodies.

Imaavy is given through a vein as an intravenous (IV) infusion by a healthcare professional, typically with a starting dose followed by treatment every two weeks.

Typical Dosing for Myasthenia Gravis

The recommended starting dose of Imaavy for generalized myasthenia gravis is 30 milligrams per kilogram of body weight. It is infused over at least 30 minutes.

Two weeks after the first dose, the recommended maintenance dose is 15 milligrams per kilogram by IV infusion over at least 15 minutes. Treatment continues at this dose every two weeks thereafter.

This information is based on prescribing information, but your healthcare provider may tailor your treatment plan. Always follow their guidance.

Imaavy Side Effects

In clinical studies of Imaavy for generalized myasthenia gravis in adults, the most common side effects occurred in about 12 percent to 18 percent of people. They include:

Respiratory tract infection
Peripheral edema (swelling in the hands, ankles, or feet)
Muscle spasms

The side effects seen in pediatric studies (age 12 to 16) were similar to those seen in the adult studies.

Serious Side Effects and Warnings

Imaavy can cause serious side effects that may require immediate medical attention. These include:

Serious infections — Imaavy may increase the risk of infections, including serious infections.
Hypersensitivity reactions — Serious allergic reactions, such as anaphylaxis or angioedema, can occur. These can cause swelling of the face, lips, mouth, tongue, or throat, and trouble breathing.
Infusion-related reactions — Reactions during or shortly after an infusion can occur, such as headache, dizziness, nausea, chills, fatigue, rash, or skin discoloration.

Get medical help right away if you think you are having a serious reaction.

How To Save on Imaavy

Janssen Biotech, Inc., the manufacturer of Imaavy, offers the IMAAVY withMe Savings Program. Eligible people with commercial or private insurance may pay as little as $0 per infusion.

To learn more, visit the IMAAVY withMe Savings Program website or call 844-4withMe (844-494-8463).

What To Know Before Taking Imaavy

Before starting Imaavy, your doctor will check whether you need age-appropriate vaccines. Because Imaavy can temporarily lower IgG levels, live vaccines are not recommended during treatment.

Tell your doctor if you have any allergies to nipocalimab-aahu or any ingredients in Imaavy. Do not take Imaavy if you have had a serious allergic reaction to nipocalimab-aahu or any of its ingredients.

Tell your doctor about all medicines you take, including prescription drugs, over-the-counter medicines, and supplements.

Before receiving Imaavy, tell your healthcare provider about all of your medical conditions, including if you:

Have or had any recent infections or have any symptoms of infection
Have or had shingles (herpes zoster) or mono (mononucleosis caused by Epstein-Barr virus)

If you miss a scheduled Imaavy infusion, you should receive your next dose as soon as possible, then continue dosing every two weeks.

If you are pregnant, planning to become pregnant, or breastfeeding while taking Imaavy, talk with your doctor about the risks and benefits. There is a pregnancy safety study for Imaavy. If Imaavy is given during pregnancy or you become pregnant while receiving Imaavy, your healthcare provider should report Imaavy exposure by contacting Janssen at 800-526-7736.

Imaavy is also FDA-approved to treat warm autoimmune hemolytic anemia (wAIHA) currently or previously treated with corticosteroids.

Community FAQs

These answers are fact-checked by our editorial staff.

How effective is Imaavy?

In a 24-week study of adults with generalized myasthenia gravis, people taking Imaavy had greater improvement in daily function and muscle weakness than those taking placebo (an inactive treatment). They had a 4.7-point average improvement in Myasthenia Gravis Activities of Daily Living (MG-ADL) scores, compared with a 3.3-point improvement with placebo. On the Quantitative Myasthenia Gravis (QMG) scale, which measures muscle weakness, people taking Imaavy improved by 4.9 points on average, compared with 2.1 points with placebo.

Should I take Imaavy for myasthenia gravis if I have an infection?

Imaavy may increase the risk of infection, and some infections can be serious. Delay starting treatment if you have an active infection until it has resolved. During treatment with Imaavy, you should be monitored for signs and symptoms of infection. Serious infections may require a pause in treatment.

Can Imaavy cause swelling in myasthenia gravis?

Yes. Swelling in the hands, ankles, or feet, called peripheral edema, is one of the most common side effects reported with Imaavy for generalized myasthenia gravis. In clinical trials, peripheral edema was reported in 12 percent of people taking Imaavy, compared with 2 percent of those taking placebo.

Do people with generalized myasthenia gravis need vaccines or need to avoid certain vaccines while taking Imaavy?

Before starting Imaavy, your doctor will check whether you need age-appropriate vaccines. Because Imaavy can temporarily lower IgG levels, live vaccines are not recommended during treatment.