Emapalumab
Emapalumab is a monoclonal antibody medication used to treat hemophagocytic lymphohistiocytosis (HLH), a rare and potentially life-threatening condition where the immune system becomes overactivated and damages the body's own tissues. It works by binding to and neutralizing interferon gamma (IFNγ), a key inflammatory protein that is excessively produced in HLH patients. This medication is specifically indicated for patients who have not responded adequately to conventional HLH therapies.
Emapalumab is an immunosuppressive monoclonal antibody that treats the rare immune disorder HLH by targeting and neutralizing interferon gamma.
Key facts at a glance
- ATC
- L04AG09
- RxNorm
- 2104604
- Generic
- Emapalumab
- Class
- atc-l04
- Brands
- Gamifant
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- injection
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
9 groupspregnancy
first trimesteravoid if possible
use only if benefits outweigh potential risks to fetus; consider alternative therapies when available
regular fetal monitoring recommended
Use with caution and monitor for adverse effects.
pregnancy
second third trimesteruse lowest effective dose
use only if benefits outweigh potential risks; consider risks of disease progression vs drug exposure
regular fetal monitoring, ultrasound assessments
Use with caution and monitor for adverse effects.
lactation
breastfeedingnot recommended
discontinue breastfeeding or avoid use; decisions should consider importance of drug to mother
monitor infant for potential adverse effects
geriatric
elderly 65no specific dose adjustment
use with caution; monitor for infections and adverse reactions; start at lower end of dosing range
regular monitoring of liver function, blood counts, and infection signs
Use with caution and monitor for adverse effects.
pediatric_age
pediatric 2 18weight-based dosing
approved for use in pediatric patients; dosing based on body weight; monitor for infections
regular monitoring of blood counts, liver function, and infection markers
renal_impairment
mild moderateno dose adjustment required
use with caution; monitor renal function
monitor renal function regularly
Use with caution and monitor for adverse effects.
renal_impairment
severeuse with caution
use only if benefits outweigh risks; limited data available
close monitoring of renal function
Use with caution and monitor for adverse effects.
hepatic_impairment
mild moderateno specific dose adjustment
use with caution; monitor liver function tests
regular monitoring of liver function
Use with caution and monitor for adverse effects.
hepatic_impairment
severeuse with caution
use only if benefits outweigh risks; limited data available
close monitoring of liver function and clinical status
Use with caution and monitor for adverse effects.
Statistics and clinical data
Drug class
Therapeutic class classification
FDA approval year
FDA approval timeline for Gamifant
Primary indication
FDA-approved therapeutic use
Mechanism of action
Pharmacological mechanism
Treatment of primary hemophagocytic lymphohistiocytosis (HLH) in adult and pediatric patients (including newborns) who have not responded to or are intolerant of conventional HLH therapy.
Emapalumab is a monoclonal antibody that binds specifically to and neutralizes interferon gamma (IFNγ), a cytokine that plays a central role in the hyperinflammatory state characteristic of HLH. By blocking IFNγ, it reduces immune system overactivation.
Administered by intravenous infusion. Patients should be monitored closely for infections during treatment. Live vaccines should be avoided during therapy. Common side effects include infections, infusion reactions, and fever. Treatment should be initiated by physicians experienced in managing HLH.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy