Reported Reactions

Drugs › Topoisomerase inhibitor

Generic name

Mitoxantrone: adverse event reports filed with FDA

4,065 reports list it as a suspect or interacting product, 2004–2026. Class: Topoisomerase inhibitor. Also reported as Mitoxantrone Injectable, Mitoxantrone /00661302/.

4,065
reports as suspect product
0% of all reports · about 181 a year
132
reports, 12 months to June 2026
183 in the 12 months before
98.8%
marked serious by the reporter
96.8% across the class
27.4%
record death among outcomes, as reported
1,114 reports · not verified by FDA

Between January 2004 and June 2026, 4,065 adverse event reports received by FDA list mitoxantrone, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (1,275) are left out of every figure here.

In the 12 months to June 2026, 132 reports listed it, down 28% from 183 in 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 181 reports a year and 0% of the 20,646,523 reports in the database, and 4.7% of the reports for the topoisomerase inhibitor class. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are febrile neutropenia (12.5%), off label use (9%) and neutropenia (8.1%). A report can list several reactions, so shares add to more than 100%; 776 different terms appear across these reports. Febrile neutropenia is recorded in 12.5% of these reports, a larger share than in the median topoisomerase inhibitor drug (7.1%).

98.8% of the reports are marked serious by the reporter (96.8% across the class); 27.4% record death among the outcomes and 32.7% record hospitalisation, as reported. 50.2% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (22.9%). 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

02142Jul 2021: 22Aug 2021: 16Sep 2021: 14Oct 2021: 20Nov 2021: 17Dec 2021: 292022Jan 2022: 15Feb 2022: 17Mar 2022: 16Apr 2022: 24May 2022: 24Jun 2022: 29Jul 2022: 29Aug 2022: 13Sep 2022: 12Oct 2022: 26Nov 2022: 17Dec 2022: 222023Jan 2023: 20Feb 2023: 21Mar 2023: 23Apr 2023: 42May 2023: 13Jun 2023: 33Jul 2023: 32Aug 2023: 19Sep 2023: 16Oct 2023: 23Nov 2023: 21Dec 2023: 92024Jan 2024: 13Feb 2024: 17Mar 2024: 7Apr 2024: 9May 2024: 22Jun 2024: 19Jul 2024: 13Aug 2024: 31Sep 2024: 22Oct 2024: 15Nov 2024: 8Dec 2024: 182025Jan 2025: 17Feb 2025: 7Mar 2025: 19Apr 2025: 10May 2025: 7Jun 2025: 16Jul 2025: 25Aug 2025: 16Sep 2025: 14Oct 2025: 12Nov 2025: 6Dec 2025: 82026Jan 2026: 11Feb 2026: 2Mar 2026: 4Apr 2026: 16May 2026: 12Jun 2026: 6

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

02364722004: 4220042005: 1452006: 1012007: 7920072008: 1102009: 842010: 9220102011: 1262012: 2002013: 11420132014: 1232015: 1452016: 17020162017: 2672018: 4722019: 28820192020: 3672021: 2222022: 24420222023: 2722024: 1942025: 15720252026: 51

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Mitoxantrone reports recording the termmedian drug in topoisomerase inhibitor

  1. Febrile neutropeniafever with low white blood cells12.5%510
  2. Off label useused for a purpose or in a way not on the label9%366
  3. Neutropenialow neutrophils, a type of white blood cell8.1%329
  4. Drug ineffectivethe medicine did not work as expected7.1%289
  5. Thrombocytopenialow platelets6.3%257
  6. Sepsisa severe body-wide response to infection5.4%218
  7. Pyrexiafever4.7%192
  8. Pancytopenialow counts of all blood cells4%162
  9. Disease progressionthe disease advanced4%161
  10. Pneumonialung infection3.8%155
  11. Infectionan infection, type not specified3.5%142
  12. Product use in unapproved indicationused for a purpose not on the label3.4%139
  13. Septic shockshock arising from infection2.7%109
  14. Deaththe patient died; cause not stated by this term2.6%106
  15. Anaemialow red blood cells2.6%105
  16. Respiratory failurethe lungs could not supply enough oxygen2.2%91
  17. Leukopenialow white blood cells2%82
  18. Cardiac failureheart failure2%80
  19. Fatiguetiredness1.9%79
  20. Acute promyelocytic leukaemia1.8%75
  21. Nauseafeeling sick1.8%73
  22. Diarrhoealoose or frequent stools1.6%66
  23. Multiple organ dysfunction syndromeseveral organs failing1.6%66
  24. Dyspnoeashortness of breath1.6%64

Top 30 of 776 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 12 drugs in the topoisomerase inhibitor 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

Death27.4%1,114
Life-threatening11.6%473
Hospitalisation (initial or prolonged)32.7%1,331
Disability1%40
Congenital anomaly0.1%6
Other serious68.9%2,801
Not serious1.2%48

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 86,440 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 22.4%97
2 to 119%367
12 to 176.7%274
18 to 4415%609
45 to 6422.9%931
65 to 7410.3%419
75 and over3%123
Age not given30.6%1,245

Patient sex

Female37.1%1,508
Male42.3%1,721
Not given20.6%836

Who reported

Physician36.3%1,475
Pharmacist1.7%69
Other health professional50.2%2,040
Lawyer0%2
Consumer or non-health professional4.6%185
Not given7.2%294

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 23.3% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Acute myeloid leukaemia98124.1%
Acute lymphocytic leukaemia3448.5%
Acute promyelocytic leukaemia1664.1%
B-cell lymphoma1503.7%
Diffuse large b-cell lymphoma1353.3%
Chronic lymphocytic leukaemia1162.9%

The indication field is filled in by the reporter and is often blank; shares are of all 4,065 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Mitoxantrone reports
Cytarabine2,03850.1%
Etoposide1,54338%
Cyclophosphamide1,18829.2%
Dexamethasone1,00624.7%
Methotrexate91822.6%
Rituximab85321%
Vincristine84220.7%
Fludarabine69717.1%
Prednisone54613.4%
Doxorubicin3929.6%

Other products listed in reports where Mitoxantrone 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

MeasureMitoxantroneTopoisomerase inhibitorAll reports
Reports as suspect product4,06586,44020,646,523
Share of that pool—4.7%0%
Reports, latest 12 months132—1,332,454
Marked serious98.8%96.8%57.4%
Death recorded among outcomes, per 1,000 reports27423191
Hospitalisation recorded, per 1,000 reports327362213
Consumer-filed share4.6%6.8%45.8%
Top term, share of reportsFebrile neutropenia 12.5%median 7.1%0.3%

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 topoisomerase inhibitor class

DrugName typeReportsLatest 12 monthsMarked serious
Etoposidegeneric62,2914,74997.9%
Irinotecan hydrochloridegeneric6,09580096.6%
Topotecangeneric3,66818796.6%
Camptosarbrand2,53511085.4%
Onivydebrand1,91161492%
Hycamtinbrand1,5261479.2%
Mitoxantrone hydrochloridegeneric1,2133997.1%
VePesidbrand9002096.7%
Topotecan hydrochloridegeneric8673696.8%
Etoposide phosphategeneric7476396.5%
Etopophosbrand622884.2%

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 Mitoxantrone reports

How many adverse event reports has FDA received for Mitoxantrone?

4,065 reports list Mitoxantrone as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 132 of them arrived in the latest 12 months. Another 1,275 list it only as a concomitant medication.

What reactions are recorded in Mitoxantrone reports?

febrile neutropenia (12.5%), off label use (9%), neutropenia (8.1%), drug ineffective (7.1%) and thrombocytopenia (6.3%). 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 Mitoxantrone was responsible.

How serious are the reports?

98.8% are marked serious by the reporter. Among the outcomes recorded, 27.4% of reports include death and 32.7% 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 (50.2%), physician (36.3%) and not given (7.2%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Mitoxantrone rising?

132 reports in the 12 months to June 2026, down 28% from 183 in 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 Mitoxantrone 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 Mitoxantrone?

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 Mitoxantrone as a suspect or interacting product; reports listing it only as a concomitant medication (1,275) 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.