Reported Reactions

Drugs › Kinase inhibitor

Generic name

Neratinib: adverse event reports filed with FDA

482 reports list it as a suspect or interacting product, 2009–2026. Class: Kinase inhibitor.

482
reports as suspect product
0% of all reports · about 29 a year
15
reports, 12 months to June 2026
16 in the 12 months before
89.6%
marked serious by the reporter
70.8% across the class
25.1%
record death among outcomes, as reported
121 reports · not verified by FDA

Between December 2009 and April 2026, 482 adverse event reports received by FDA list neratinib, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (82) are left out of every figure here.

In the 12 months to June 2026, 15 reports listed it, close to the 16 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 29 reports a year and 0% of the 20,646,523 reports in the database, and 0.1% of the reports for the kinase 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 diarrhoea (42.5%), off label use (30.3%) and disease progression (18.5%). A report can list several reactions, so shares add to more than 100%; 187 different terms appear across these reports. Diarrhoea is recorded in 42.5% of these reports, a larger share than in the median kinase inhibitor drug (6.9%).

89.6% of the reports are marked serious by the reporter (70.8% across the class); 25.1% record death among the outcomes and 54.8% record hospitalisation, as reported. 57.1% of the reports came from physicians, and the largest patient age group is 45 to 64 (37.1%). 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

01326Jul 2021: 26Aug 2021: 17Sep 2021: 10Oct 2021: 5Nov 2021: 2Dec 2021: 72022Jan 2022: 9Feb 2022: 7Mar 2022: 2Apr 2022: 5May 2022: 7Jun 2022: 3Jul 2022: 4Aug 2022: 10Sep 2022: 5Oct 2022: 1Nov 2022: 11Dec 2022: 102023Jan 2023: 2Feb 2023: 5Mar 2023: 6Apr 2023: 9May 2023: 4Jun 2023: 17Jul 2023: 2Aug 2023: 2Sep 2023: 4Oct 2023: 2Nov 2023: 2Dec 2023: 32024Jan 2024: 4Feb 2024: 1Mar 2024: 1Apr 2024: 1May 2024: 0Jun 2024: 10Jul 2024: 2Aug 2024: 0Sep 2024: 3Oct 2024: 0Nov 2024: 0Dec 2024: 42025Jan 2025: 2Feb 2025: 3Mar 2025: 1Apr 2025: 0May 2025: 0Jun 2025: 1Jul 2025: 0Aug 2025: 3Sep 2025: 1Oct 2025: 1Nov 2025: 0Dec 2025: 02026Jan 2026: 5Feb 2026: 1Mar 2026: 1Apr 2026: 3May 2026: 0Jun 2026: 0

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

0631262009: 220092010: 222011: 1020112012: 152013: 1620132014: 72015: 220152016: 12017: 420172018: 192019: 4620192020: 322021: 12620212022: 742023: 5820232024: 262025: 1220252026: 10

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Neratinib reports recording the termmedian drug in kinase inhibitor

  1. Diarrhoealoose or frequent stools42.5%205
  2. Off label useused for a purpose or in a way not on the label30.3%146
  3. Disease progressionthe disease advanced18.5%89
  4. Nauseafeeling sick17.6%85
  5. Fatiguetiredness15.1%73
  6. Vomitingbeing sick14.7%71
  7. Decreased appetitereduced appetite14.1%68
  8. Coughcough13.1%63
  9. Neuropathy peripheralnerve damage in hands or feet12.7%61
  10. Weight decreasedweight loss10.8%52
  11. Product use issuea problem in how the product was used10.2%49
  12. Constipationconstipation9.5%46
  13. Neutropenialow neutrophils, a type of white blood cell9.5%46
  14. Pyrexiafever9.1%44
  15. Hypokalaemialow blood potassium8.7%42
  16. Rash pruritican itchy rash8.7%42
  17. Thrombocytopenialow platelets8.7%42
  18. Lacrimation increasedwatery eyes6.6%32
  19. Condition aggravatedthe condition being treated got worse6.2%30
  20. Dyspnoeashortness of breath6%29
  21. Acute kidney injurysudden loss of kidney function5.8%28
  22. Colitisinflamed bowel5.8%28
  23. Dyspepsiaindigestion5.8%28
  24. Hypoaesthesianumbness5.8%28
  25. Dysphoniaa hoarse voice5.4%26
  26. Folate deficiency5.4%26

Top 30 of 187 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 100 drugs in the kinase 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

Death25.1%121
Life-threatening3.1%15
Hospitalisation (initial or prolonged)54.8%264
Disability1%5
Congenital anomaly0.2%1
Other serious64.3%310
Not serious10.4%50

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 849,161 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 20%0
2 to 110%0
12 to 170%0
18 to 443.9%19
45 to 6437.1%179
65 to 7412.7%61
75 and over6.8%33
Age not given39.4%190

Patient sex

Female64.9%313
Male3.1%15
Not given32%154

Who reported

Physician57.1%275
Pharmacist0.8%4
Other health professional31.7%153
Lawyer0%0
Consumer or non-health professional7.5%36
Not given2.9%14

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 26.6% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Her2 positive breast cancer11223.2%
Breast cancer10521.8%
Breast cancer metastatic8217%
Metastatic neoplasm163.3%
Her-2 positive breast cancer112.3%
Neoplasm61.2%

The indication field is filled in by the reporter and is often blank; shares are of all 482 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Neratinib reports
Trastuzumab24450.6%
Pertuzumab19941.3%
Capecitabine19640.7%
Docetaxel17436.1%
Loperamide17035.3%
Dexamethasone14530.1%
Domperidone13127.2%
Ado-trastuzumab emtansine12125.1%
Lansoprazole9519.7%
Paclitaxel8317.2%

Other products listed in reports where Neratinib 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

MeasureNeratinibKinase inhibitorAll reports
Reports as suspect product482849,16120,646,523
Share of that pool—0.1%0%
Reports, latest 12 months15—1,332,454
Marked serious89.6%70.8%57.4%
Death recorded among outcomes, per 1,000 reports25119091
Hospitalisation recorded, per 1,000 reports548264213
Consumer-filed share7.5%42.3%45.8%
Top term, share of reportsDiarrhoea 42.5%median 6.9%3.1%

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 kinase inhibitor class

DrugName typeReportsLatest 12 monthsMarked serious
Ibrancebrand81,9122,38047.1%
Imbruvicabrand67,0392,28374.4%
Cabometyxbrand41,8184,90440.4%
Sutentbrand33,21517574.5%
Afinitorbrand30,70616171.3%
Sprycelbrand27,25555749.7%
Tasignabrand24,91132870.9%
Kisqalibrand24,6033,41379.2%
Ofevbrand23,9072,43466.9%
Gleevecbrand23,1328174.7%
Tagrissobrand23,0851,41092.3%
Lenvimabrand22,3502,64387.3%
Votrientbrand22,08411960.9%
Mekinistbrand17,07091664%
Inlytabrand15,69638860.9%

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 Neratinib reports

How many adverse event reports has FDA received for Neratinib?

482 reports list Neratinib as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 15 of them arrived in the latest 12 months. Another 82 list it only as a concomitant medication.

What reactions are recorded in Neratinib reports?

diarrhoea (42.5%), off label use (30.3%), disease progression (18.5%), nausea (17.6%) and fatigue (15.1%). 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 Neratinib was responsible.

How serious are the reports?

89.6% are marked serious by the reporter. Among the outcomes recorded, 25.1% of reports include death and 54.8% 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?

physician (57.1%), other health professional (31.7%) and consumer or non-health professional (7.5%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Neratinib rising?

15 reports in the 12 months to June 2026, close to the 16 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 Neratinib 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 Neratinib?

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 Neratinib as a suspect or interacting product; reports listing it only as a concomitant medication (82) 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.