Ropeginterferon Alfa-2b
Ropeginterferon Alfa-2b is a long-acting, monotherapy medication classified as a type I interferon used to treat polycythemia vera (PV), a rare chronic blood cancer characterized by overproduction of blood cells in the bone marrow. Administered by subcutaneous injection, this medication works by binding to interferon alfa receptors on bone marrow cells, initiating a signaling cascade that helps regulate abnormal blood cell production and reduce disease burden.
A type I interferon therapy for polycythemia vera that regulates blood cell production through receptor-mediated signaling in the bone marrow.
This medication carries a boxed (black box) warning — the strongest type of FDA warning. Review the full prescribing information before use.
Key facts at a glance
- ATC
- L03AB15
- RxNorm
- 2587059
- Generic
- Ropeginterferon Alfa-2b
- Class
- atc-l03
- Brands
- Besremi
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- prefilled syringe
- 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
- 100 mcg every 2 weeks
- Maximum
- consult physician
- Frequency
- every 2 weeks
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 50 mcg once weekly
- Maximum
- consult physician
- Frequency
- once weekly
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 50 mcg every 2 weeks
- Maximum
- consult physician
- Frequency
- every 2 weeks
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
10 groupspregnancy
first trimesteravoid if possible
avoid use during pregnancy unless benefits outweigh risks
regular fetal monitoring
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
second trimesteravoid if possible
discontinue therapy if pregnancy occurs, consider risks versus benefits
regular fetal monitoring and ultrasound assessments
Use of this medication in this population requires careful consideration of risks and benefits.
pregnancy
third trimesteravoid if possible
avoid use near term, consider alternative therapies
fetal monitoring and growth assessments
Use of this medication in this population requires careful consideration of risks and benefits.
lactation
not applicablediscontinue breastfeeding
discontinue breastfeeding during treatment and for at least 4 weeks after last dose
monitor infant for signs of infection or liver abnormalities
Use of this medication in this population requires careful consideration of risks and benefits.
pediatric_age
not applicablenot recommended
not approved for use in patients under 18 years of age; safety and efficacy not established in pediatric populations
not applicable
Use of this medication in this population requires careful consideration of risks and benefits.
geriatric
not applicableno specific dose adjustment required
use with caution due to increased susceptibility to adverse effects; start at lower end of dosing range
regular monitoring of complete blood count, liver function, and renal function
Use with caution and monitor for adverse effects.
renal_impairment
moderatereduce dose
use with caution; dose reduction may be required in patients with creatinine clearance below 50 mL/min
monitor renal function and adjust dose based on tolerability
Use with caution and monitor for adverse effects.
renal_impairment
severeavoid or significantly reduce dose
use with extreme caution; limited data available for patients with severe renal impairment
close monitoring of renal function and adverse effects
Use of this medication in this population requires careful consideration of risks and benefits.
hepatic_impairment
mildno specific adjustment
use with caution; no specific dose adjustment required for mild impairment
monitor liver function tests regularly
Use with caution and monitor for adverse effects.
hepatic_impairment
moderate to severeavoid use
contraindicated in patients with moderate to severe hepatic impairment (Child-Pugh B and C)
not applicable
Use of this medication in this population requires careful consideration of risks and benefits.
Statistics and clinical data
FDA approval year
First FDA approval for Besremi
Drug class
Pharmacological classification
Primary indication
Therapeutic indication
Mechanism of action
Pharmacodynamic properties
Treatment of polycythemia vera in adults, particularly for patients who have an inadequate response to or are intolerant of hydroxyurea.
As a type I interferon, it binds to the interferon alfa receptor (IFNAR) on bone marrow cells, triggering downstream signaling cascades that help normalize blood cell production and reduce the excessive red blood cell counts characteristic of polycythemia vera.
Administered as a subcutaneous injection with individualized dosing. Common side effects include flu-like symptoms, liver enzyme elevations, and depression. Requires regular monitoring of blood counts and liver function. Contraindicated in patients with severe psychiatric conditions, autoimmune disorders, or uncontrolled cardiac disease.
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