Reported Reactions

Drugs › Thrombopoietin receptor agonist

Generic name

Romiplostim: adverse event reports filed with FDA

2,078 reports list it as a suspect or interacting product, 2008–2026. Class: Thrombopoietin receptor agonist.

2,078
reports as suspect product
0% of all reports · about 116 a year
263
reports, 12 months to June 2026
268 in the 12 months before
92.1%
marked serious by the reporter
68.8% across the class
22%
record death among outcomes, as reported
457 reports · not verified by FDA

2,078 adverse event reports received by FDA list romiplostim, a generic name as a suspect or interacting product, from August 2008 to June 2026. A further 678 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 263 reports listed it, close to the 268 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 116 reports a year and 0% of the 20,646,523 reports in the database, and 6.1% of the reports for the thrombopoietin receptor agonist class. How many people take it is not in the data, so a count is not a rate of occurrence.

The MedDRA terms listed most often are off label use (22.3%), drug ineffective (11.1%) and therapy non-responder (7.3%). A report can list several reactions, so shares add to more than 100%; 441 different terms appear across these reports. Off label use is recorded in 22.3% of these reports, a larger share than in the median thrombopoietin receptor agonist drug (8.2%).

92.1% of the reports are marked serious by the reporter (68.8% across the class); 22% record death among the outcomes and 34.8% record hospitalisation, as reported. 53% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (19.1%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

02040Jul 2021: 4Aug 2021: 12Sep 2021: 20Oct 2021: 17Nov 2021: 13Dec 2021: 202022Jan 2022: 21Feb 2022: 7Mar 2022: 21Apr 2022: 11May 2022: 13Jun 2022: 11Jul 2022: 12Aug 2022: 14Sep 2022: 16Oct 2022: 10Nov 2022: 11Dec 2022: 112023Jan 2023: 16Feb 2023: 28Mar 2023: 9Apr 2023: 25May 2023: 15Jun 2023: 18Jul 2023: 18Aug 2023: 10Sep 2023: 7Oct 2023: 8Nov 2023: 22Dec 2023: 192024Jan 2024: 10Feb 2024: 16Mar 2024: 26Apr 2024: 13May 2024: 11Jun 2024: 14Jul 2024: 27Aug 2024: 20Sep 2024: 14Oct 2024: 24Nov 2024: 12Dec 2024: 312025Jan 2025: 14Feb 2025: 40Mar 2025: 18Apr 2025: 28May 2025: 15Jun 2025: 25Jul 2025: 36Aug 2025: 16Sep 2025: 22Oct 2025: 18Nov 2025: 34Dec 2025: 212026Jan 2026: 10Feb 2026: 26Mar 2026: 40Apr 2026: 13May 2026: 14Jun 2026: 13

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

01442872008: 2620082009: 452010: 2920102011: 412012: 6720122013: 422014: 3320142015: 562016: 8420162017: 852018: 10720182019: 1382020: 18020202021: 1712022: 15820222023: 1952024: 21820242025: 2872026: 1162026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Romiplostim reports recording the termmedian drug in thrombopoietin receptor agonist

  1. Off label useused for a purpose or in a way not on the label22.3%463
  2. Drug ineffectivethe medicine did not work as expected11.1%230
  3. Therapy non-responderthe treatment did not work7.3%151
  4. Thrombocytopenialow platelets7.3%151
  5. Immune thrombocytopenia6.5%135
  6. Platelet count decreasedlow platelet count6.1%127
  7. Deaththe patient died; cause not stated by this term5.5%114
  8. Pulmonary embolisma blood clot in the lung3.7%76
  9. Treatment failurethe treatment did not work3.7%76
  10. Haemorrhagebleeding3.5%73
  11. Deep vein thrombosisa blood clot in a deep vein3.4%71
  12. Pneumonialung infection3.4%71
  13. Headachehead pain3.2%66
  14. Infectionan infection, type not specified2.7%57
  15. Anaemialow red blood cells2.6%54
  16. Thrombocytosis2.6%53
  17. Sepsisa severe body-wide response to infection2.5%52
  18. Epistaxisnosebleed2.2%46
  19. Gastrointestinal haemorrhagebleeding in the stomach or bowel1.9%39
  20. Myelofibrosis1.8%37
  21. Petechiaetiny bleeding spots in the skin1.8%37
  22. Maternal exposure during pregnancythe mother took the medicine during pregnancy1.7%36
  23. Diarrhoealoose or frequent stools1.6%34
  24. Hospitalisationadmission to hospital1.6%33

Top 30 of 441 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 5 drugs in the thrombopoietin receptor agonist class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death22%457
Life-threatening7.4%154
Hospitalisation (initial or prolonged)34.8%724
Disability1.2%25
Congenital anomaly0.1%3
Other serious68.2%1,418
Not serious7.9%165

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 33,996 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 21.4%30
2 to 114.5%94
12 to 172.7%57
18 to 4415.5%323
45 to 6419.1%396
65 to 7410.9%226
75 and over14.1%294
Age not given31.7%658

Patient sex

Female42.8%889
Male34.7%722
Not given22.5%467

Who reported

Physician41.1%854
Pharmacist3.3%69
Other health professional53%1,102
Lawyer0%0
Consumer or non-health professional2.3%47
Not given0.3%6

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 28.9% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Immune thrombocytopenia61129.4%
Thrombocytopenia28813.9%
Aplastic anaemia1949.3%
Immune thrombocytopenic purpura1818.7%
Idiopathic thrombocytopenic purpura1356.5%
Myelodysplastic syndrome291.4%

The indication field is filled in by the reporter and is often blank; shares are of all 2,078 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Romiplostim reports
Rituximab38418.5%
Eltrombopag29214.1%
Prednisolone2039.8%
Prednisone1949.3%
Dexamethasone1728.3%
Mycophenolate mofetil1637.8%
Cyclosporine1316.3%
Cyclophosphamide1256%
Human immunoglobulin g1235.9%
Azathioprine1065.1%

Other products listed in reports where Romiplostim is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureRomiplostimThrombopoietin receptor agonistAll reports
Reports as suspect product2,07833,99620,646,523
Share of that pool—6.1%0%
Reports, latest 12 months263—1,332,454
Marked serious92.1%68.8%57.4%
Death recorded among outcomes, per 1,000 reports22019991
Hospitalisation recorded, per 1,000 reports348234213
Consumer-filed share2.3%38.5%45.8%
Top term, share of reportsOff label use 22.3%median 8.2%4.1%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Other drugs in the thrombopoietin receptor agonist class

DrugName typeReportsLatest 12 monthsMarked serious
Promactabrand14,56116150.1%
Nplatebrand11,56531074.3%
Eltrombopag olaminegeneric3,08820698.9%
Eltrombopaggeneric2,70435994.2%

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.

Questions about Romiplostim reports

How many adverse event reports has FDA received for Romiplostim?

2,078 reports list Romiplostim as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 263 of them arrived in the latest 12 months. Another 678 list it only as a concomitant medication.

What reactions are recorded in Romiplostim reports?

off label use (22.3%), drug ineffective (11.1%), therapy non-responder (7.3%), thrombocytopenia (7.3%) and immune thrombocytopenia (6.5%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Romiplostim was responsible.

How serious are the reports?

92.1% are marked serious by the reporter. Among the outcomes recorded, 22% of reports include death and 34.8% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

other health professional (53%), physician (41.1%) and pharmacist (3.3%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Romiplostim rising?

263 reports in the 12 months to June 2026, close to the 268 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Romiplostim was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Romiplostim?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Romiplostim as a suspect or interacting product; reports listing it only as a concomitant medication (678) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.