Approved indications: Imaavy is indicated as an add-on treatment for generalized myasthenia gravis in adults and adolescents 12 years and older who test positive for anti-AChR or anti-MuSK antibodies.

Off-label or investigational uses: Nipocalimab, the active ingredient in Imaavy, is being studied in clinical trials for several other antibody-mediated autoimmune conditions, but it is not currently approved for those diseases, and any off-label use would be specialist-directed and based on limited evidence.

Efficacy expectations:

• Many patients begin to notice some improvement in myasthenia gravis symptoms within about 1 to 2 weeks of the first infusion, with further gains over the following weeks.
• In a 24-week pivotal trial, patients receiving Imaavy plus standard therapy had a greater average improvement in MG-ADL scores (about 4.7-point reduction vs 3.3 points with placebo plus standard care) and up to roughly 75% reductions in disease-causing antibodies, with benefits maintained out to about 20 months in an extension study for many participants.
• Indirect comparisons suggest that Imaavy provides similar or better sustained disease control than other FcRn blockers for gMG, with the convenience of every-2-week IV dosing rather than more frequent injections for some alternatives, although individual responses vary.

Typical dosing: Imaavy is given only as an intravenous infusion in a clinic or infusion center, starting with a loading dose of 30 mg/kg over at least 30 minutes, followed 2 weeks later by maintenance doses of 15 mg/kg over at least 15 minutes every 2 weeks in both adults and adolescents 12 years and older, with each dose calculated from current body weight.

How it is given: The medicine is diluted in 0.9% sodium chloride (normal saline) and infused through a vein using a filter; patients are monitored during the infusion and for about 30 minutes afterward for signs of allergic or infusion-related reactions.

Special dosing instructions:

• Before starting therapy, clinicians typically review and update age-appropriate vaccinations, because live vaccines are generally avoided during treatment and vaccine responses may be blunted.
• If mild to moderate infusion reactions occur, future infusions may be slowed and premedications (such as antihistamines or other supportive medicines) may be given; severe reactions may require stopping the infusion permanently.
• No formal dose adjustments have been established for mild to moderate kidney impairment, but people with complex medical conditions or on multiple immunosuppressive therapies may need individualized dosing and monitoring plans.

Missed dose: If a scheduled infusion is missed, the maintenance dose should be given as soon as possible and then the every-2-week schedule resumed from that new date, so patients should contact their prescriber or infusion center promptly to reschedule.

Overdose: There is no specific antidote for an overdose of Imaavy; management is supportive—monitoring for infections, infusion reactions, and other side effects—so any suspected dosing error or overdose should be reported immediately to the treating team, emergency services, or a poison control center.

Common side effects: The most common side effects (often affecting at least 1 in 10 people) are respiratory tract infections (such as colds, bronchitis, pneumonia, or COVID-19), swelling of the hands, ankles, or feet (peripheral edema), and muscle spasms; other frequently reported effects include urinary or oral infections, herpes infections (shingles or cold sores), diarrhea, cough, abdominal or back pain, fever, dizziness, nausea, insomnia, mild increases in blood pressure, and changes in cholesterol, which are usually mild to moderate and tend to occur within days to weeks of infusions.

Serious or rare adverse effects needing immediate attention:

• Signs of serious infection, such as high fever, chills or shivering, shortness of breath, chest pain, persistent or worsening cough, burning or pain with urination, or a painful blistering rash suggestive of shingles.
• Severe allergic (hypersensitivity) reactions, including swelling of the face, lips, tongue, or throat, trouble swallowing or breathing, chest tightness, or widespread hives.
• Severe infusion-related reactions during or shortly after the drip, such as intense headache, flushing, rash, severe nausea, feeling faint, or flu-like symptoms.

Warnings and precautions:

• Infections: Imaavy lowers IgG levels and can increase the risk of new or reactivated infections (including herpes zoster and other viral, bacterial, or fungal infections), so active infections should be treated before starting, and patients should promptly report any infection symptoms.
• Vaccinations: Age-appropriate vaccines should be updated before treatment; live vaccines are generally not recommended during therapy, and responses to vaccines may be reduced while IgG levels are suppressed.
• Pregnancy and breastfeeding: Human data are limited; the drug crosses the placenta and may reduce a newborn’s antibodies for several months, potentially increasing infection risk and affecting vaccine responses, and it is excreted in breast milk, so risks and benefits of treatment, pregnancy, and breastfeeding should be carefully discussed with the prescriber.
• Age and organ function: Imaavy is approved only for patients 12 years and older; safety in younger children is unknown, and although no specific dose adjustment is defined for mild to moderate kidney impairment, experience in severe kidney or significant liver disease is limited, so closer monitoring may be needed.

Safety compared with similar drugs: Overall, Imaavy’s safety profile is broadly similar to other FcRn blockers used for gMG, with infections, infusion reactions, and lipid changes as the main concerns; unlike complement inhibitors such as eculizumab or ravulizumab, it does not carry a boxed warning for life-threatening meningococcal infection or require mandatory meningococcal vaccination.

Reporting side effects and finding updates: Side effects should be reported to your healthcare team and can also be reported directly to the FDA’s MedWatch program (online or by calling 1-800-FDA-1088) or to the manufacturer; updated safety information is provided in the medication guide, prescribing information, and on regulatory or manufacturer websites.

Drug and biologic interactions:

• Imaavy can lower blood levels and reduce the effectiveness of other medicines that depend on the neonatal Fc receptor (FcRn) for recycling, such as intravenous or subcutaneous immunoglobulin (IVIG/SCIG) products and many monoclonal antibody therapies, so clinicians may monitor response closely, adjust treatment timing, or consider alternatives.
• No specific interactions with common oral medicines through liver enzyme pathways have been identified, but all prescription drugs, over-the-counter medicines, vitamins, and herbal supplements should be reviewed with the prescriber before and during treatment.

Vaccines and immune therapies: Because Imaavy reduces IgG levels, responses to vaccines and some antibody-based therapies can be diminished; live vaccines are generally avoided during treatment, and vaccine schedules are often completed or updated before starting therapy whenever possible.

Food, alcohol, and lifestyle: No specific food interactions are known and the medicine is not taken by mouth; moderate alcohol use has not been specifically studied with Imaavy, so alcohol intake should be discussed with the clinician in the context of other health conditions and medications.

Conditions requiring caution:

• Current, recent, or recurrent serious infections, or chronic infections.
• History of herpes zoster (shingles) or other latent viral infections that might reactivate.
• Planned major surgery or concurrent use of other potent immunosuppressive therapies.
• Pregnancy, plans for pregnancy, or breastfeeding, because of limited data and potential effects on the baby’s immune system.
• Use of multiple biologic drugs or immunoglobulin products for other autoimmune diseases, due to possible interaction at the FcRn level.

Monitoring needs: During treatment, clinicians typically monitor for signs and symptoms of infection, infusion or allergic reactions around each infusion, and may periodically check blood counts and lipid levels, along with clinical scales (such as MG-ADL) to assess disease control.

Q: What is Imaavy used for?
A: Imaavy is used to treat generalized myasthenia gravis in adults and children 12 years and older who have specific antibodies (anti-AChR or anti-MuSK) that attack the connection between nerves and muscles.

Q: How quickly might Imaavy start to improve my symptoms?
A: In clinical studies, many people began to notice some improvement within about 1 to 2 weeks after the first infusion, with further gains building over several months of treatment, though response varies from person to person.

Q: How is Imaavy given and how often will I need it?
A: Imaavy is given as an intravenous infusion by a healthcare professional, with one longer loading infusion first and then shorter maintenance infusions every 2 weeks.

Q: What are the most common side effects I should watch for?
A: The most common problems are infections affecting the breathing passages, swelling of the hands or feet, and muscle spasms, along with occasional urinary or oral infections, shingles or cold sores, stomach upset, fatigue, headache, or changes in cholesterol.

Q: Can I get vaccines while being treated with Imaavy?
A: Your vaccines should be reviewed and updated before starting treatment, and live vaccines are generally avoided while you are on Imaavy because it lowers IgG levels and could reduce vaccine effectiveness.

Q: Will Imaavy replace my other myasthenia gravis medicines?
A: In studies, Imaavy was used in addition to standard therapies such as steroids, acetylcholinesterase inhibitors, or other immunosuppressants, so your doctor may continue some of your existing medicines and adjust them over time based on how you respond.

Storage: Imaavy vials are stored by healthcare professionals in a refrigerator at 36°F to 46°F (2°C to 8°C) in the original carton, protected from light, and must not be frozen or shaken; once diluted, the solution is used promptly or stored only for a limited time before it must be discarded.

For patients: You will not store Imaavy at home—your clinic or infusion center handles all storage and preparation, and you mainly need to keep your appointments and follow any pre-infusion instructions.

Disposal: Unused or expired vials and used IV materials are disposed of by the infusion center or pharmacy as medical waste, so patients should not attempt to dispose of this medicine themselves.