Imaavy (Nipocalimab-Aahu) for Myasthenia Gravis

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

How Imaavy Works and How It’s Taken

Imaavy works by blocking neonatal Fc receptor (FcRn), a protein that helps keep immunoglobulin G (IgG) antibodies in the body. This lowers the amount of IgG, including harmful antibodies that attack the connection between nerves and muscles. By reducing these antibodies, Imaavy may help improve muscle strength and help control symptoms of generalized myasthenia gravis.

Doctors may prescribe Imaavy when someone has generalized myasthenia gravis. The treatment is given as an intravenous infusion, which means it goes into a vein. Treatment starts with one infusion. Two weeks later, a second infusion is given. After that, it is given every two weeks.

Connect with others who understand life with myasthenia gravis. Join MGteam for free.

Imaavy Side Effects

In clinical studies of Imaavy for generalized myasthenia gravis, the most common side effects occurred in between 12 percent and 18 percent of people. These side effects were:

Respiratory tract infections (such as colds or other breathing infections)
Peripheral edema (swelling, often in the hands, feet, ankles, or legs)
Muscle spasms (sudden, involuntary muscle tightening)

These less-common side effects appeared for less than 8 percent of people taking Imaavy:

Urinary tract infections
Herpes zoster or herpes simplex infection
Mouth infections
Pain in the abdomen or back
Nausea or dizziness
High blood pressure
Insomnia
Fever
Cough
Diarrhea
Anemia (low levels of red blood cells)

Serious Side Effects and Warnings

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

Serious infections (including herpes zoster or Epstein-Barr virus infections)
Hypersensitivity (allergic) reactions (including anaphylaxis, angioedema, rash, hives, or eczema)
Infusion-related reactions (headache, flu-like symptoms, rash, nausea, fatigue, dizziness, chills, 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 insurance may pay as little as $0 per infusion.

The program offers support for the cost of the medicine and certain costs related to infusion administration and follow-up monitoring. To learn more, visit the Imaavy website or call 888-750-8733.

What To Know Before Taking Imaavy

Before starting Imaavy, your doctor will check whether you need age-appropriate vaccines. Let your doctor know if you have recently received or are scheduled to receive an immunization.

Tell your doctor about all the medicines you take, including prescription drugs, over-the-counter medicines, vitamins, and herbal supplements. Also let your doctor know if you have had recent infections or have any symptoms of an infection.

Tell your doctor if you have any allergies to nipocalimab-aahu or any ingredients in Imaavy.

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.

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 who were anti-acetylcholine receptor or anti-muscle-specific tyrosine kinase antibody positive, people taking Imaavy had greater improvement in daily function than those taking placebo (an inactive treatment).

Researchers used a tool called Myasthenia Gravis Activities of Daily Living (MG-ADL) to measure participants’ progress. Those taking Imaavy saw their MG-ADL score improve by 4.7 points, compared with 3.3 points for those taking placebo. A second tool used to measure muscle weakness, Quantitative Myasthenia Gravis (QMG), also showed reduced muscle weakness for those taking Imaavy.

Should I take Imaavy for generalized 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 people with generalized 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, healthcare providers should evaluate whether age-appropriate vaccines are needed. Live vaccines are not recommended during treatment with Imaavy. The safety of live vaccines and how well vaccines work during treatment are not known.