Prescription medicine
Ropeginterferon alfa 2b Brand names: Besremi
Ropeginterferon alfa 2b (Besremi) is a prescription medicine. No generic is listed in FDA's NDC Directory.
- No generic listed
- Boxed warning
Check it at the source: the ropeginterferon alfa 2b FDA label on DailyMed (effective August 25, 2026); every ropeginterferon alfa 2b label on DailyMed.
Highlights of the record
FDA label of August 25, 2026; NDC Directory, Drugs@FDA and Orange Book, October 8, 2026
RISK OF SERIOUS DISORDERS.
Risk of Serious Disorders: Interferon alfa products may cause or aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. Patients should be monitored closely with periodic clinical and laboratory evaluations. Therapy should be withdrawn in patients with persistently severe or worsening signs or symptoms of these conditions. In many, but not all cases, these disorders resolve after stopping therapy [see Warnings and Precautions ( 5.1 , 5,2 , 5.3 , 5.4 ) and Adverse Reactions ( 6.1 )]. WARNING: RISK OF SERIOUS DISORDERS See full prescribing information for complete boxed warning. Risk of Serious Disorders: Interferon alfa products may cause or aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. Monitor closely and withdraw therapy with persistently severe or worsening signs or symptoms of the above disorders.
Used for
From the label: indications and usageBESREMi is an interferon alfa-2b indicated for:
The treatment of adults with essential thrombocythemia.
Forms and strengths
- 0.5ml
Injection; injection (solution).
On the market
- Generic approvals
- No generic approved
- Labelers listed (NDC)
- 1 of which 0 under generic applications, 1 under brand applications, repackagers included
Supply and safety
- Pharmacy cost (NADAC)
- Not in the survey
- Shortage (FDA)
- No current entry
- Recalls by its makers (FDA)
- No recall recorded
- FAERS reports
- 1,776 through July 30, 2026
What is ropeginterferon alfa 2b used for?
From the label: indications and usageBESREMi is an interferon alfa-2b indicated for:
The treatment of adults with essential thrombocythemia. ( 1.1 )
The treatment of adults with polycythemia vera. ( 1.2 ) 1.1 Essential Thrombocythemia BESREMi is indicated for the treatment of adults with essential thrombocythemia. 1.2 Polycythemia Vera BESREMi is indicated for the treatment of adults with polycythemia vera.
FDA pharmacologic class: Interferon alfa-2b.
Source: FDA drug label (BESREMi), PharmaEssentia USA, effective August 25, 2026 (SPL set 9583405d-53a0-49dc-88eb-5e6384ebabcb), via openFDA; the full label on DailyMed
What does the patient leaflet for ropeginterferon alfa 2b say first?
The FDA-approved Medication Guide or Patient Information that comes with the medicine, in its own words.
From the patient leaflet: What is the most important information I should know about BESREMi?BESREMi can cause serious side effects that may cause death, be life threatening, or worsen certain serious conditions that you may already have. Tell your healthcare provider right away if you get any of the problems listed below during treatment with BESREMi. • Mental health problems, including depression and suicide. BESREMi may cause you to develop mood or behavior problems that may get worse during treatment with BESREMi or after your last dose. Your healthcare provider should closely monitor you for new or worsening depression and any unusual changes in mood or behavior during treatment with BESREMi. If you have thoughts of hurting yourself or thoughts of suicide, stop using BESREMi right away. You, your caregiver, or family member should tell your healthcare provider or get medical help right away if you develop any of the following signs or symptoms, especially if they are new, worse, or worry you: o thoughts about suicide or dying o new or worse depression o feeling very agitated or restless o trouble sleeping (insomnia) o acting aggressive, being angry, or violent o an extreme increase in activity or talking (mania) o suicide attempts o new or worse anxiety o panic attacks o new or worse irritability o acting on dangerous impulses o other unusual changes in behavior or mood • New or worsening autoimmune problems. BESREMi may cause autoimmune problems (a condition where the body’s immune cells attack other cells or organs in the body), including thyroid problems, increased blood sugar (hyperglycemia), and type I diabetes. In some people who already have an autoimmune problem, it may get worse during your treatment with BESREMi. […]
From the patient leaflet: What should I avoid during treatment with BESREMi?BESREMi may cause neurologic symptoms including dizziness, sleepiness, and hallucinations. Avoid driving or using heavy machinery if you develop any of these neurologic symptoms during treatment with BESREMi.
From the patient leaflet: How should I store BESREMi?Store BESREMi in the refrigerator between 36 o F to 46 o F (2 o C to 8 o C). • Keep BESREMi in the original carton to protect it from light. • Do not freeze BESREMi. Keep BESREMi and all medicines out of the reach of children.
Source: FDA drug label (BESREMi), PharmaEssentia USA, effective August 25, 2026 (SPL set 9583405d-53a0-49dc-88eb-5e6384ebabcb), via openFDA; the full label on DailyMed
Is there a generic for ropeginterferon alfa 2b (Besremi)?
No generic ropeginterferon alfa 2b is approved (Drugs@FDA, October 8, 2026).
Source: Drugs@FDA, FDA NDC Directory and the Orange Book (openFDA bulk files, October 8, 2026)
What do FAERS reports show for ropeginterferon alfa 2b?
The FDA Adverse Event Reporting System holds 1,776 reports that list ropeginterferon alfa 2b among the medicines taken, through July 30, 2026, each a report of something that happened, not proof the medicine caused it; 29 are coded as a death and 166 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is.
Reports received each year
The most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026
What next?
- Ropeginterferon alfa 2b side effects
- the label's list beside FAERS reports
- Check an interaction
- what two or more labels say about each other