Reported Reactions

Drugs › Kinase inhibitor

Brand name · Abemaciclib

Verzenio: adverse event reports filed with FDA

14,225 reports list it as a suspect or interacting product, 2016–2026. Class: Kinase inhibitor.

14,225
reports as suspect product
0.1% of all reports · about 1,485 a year
2,610
reports, 12 months to June 2026
2,378 in the 12 months before
35.1%
marked serious by the reporter
70.8% across the class
6%
record death among outcomes, as reported
848 reports · not verified by FDA

Between December 2016 and June 2026, 14,225 adverse event reports received by FDA list the brand name Verzenio (abemaciclib) as a suspect or interacting product. Reports that mention it only as a concomitant medication (401) are left out of every figure here.

In the 12 months to June 2026, 2,610 reports listed it, up 10% from 2,378 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 1,485 reports a year and 0.1% of the 20,646,523 reports in the database, and 1.7% 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 (34.3%), fatigue (13.8%) and nausea (11.6%). A report can list several reactions, so shares add to more than 100%; 822 different terms appear across these reports. Diarrhoea is recorded in 34.3% of these reports, a larger share than in the median kinase inhibitor drug (6.9%).

35.1% of the reports are marked serious by the reporter (70.8% across the class); 6% record death among the outcomes and 15.2% record hospitalisation, as reported. 61.1% of the reports came from consumers, and the largest patient age group is 45 to 64 (29.1%). 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

0133265Jul 2021: 96Aug 2021: 151Sep 2021: 123Oct 2021: 96Nov 2021: 110Dec 2021: 1142022Jan 2022: 119Feb 2022: 104Mar 2022: 117Apr 2022: 89May 2022: 111Jun 2022: 134Jul 2022: 141Aug 2022: 136Sep 2022: 131Oct 2022: 136Nov 2022: 107Dec 2022: 1202023Jan 2023: 117Feb 2023: 115Mar 2023: 127Apr 2023: 140May 2023: 137Jun 2023: 179Jul 2023: 158Aug 2023: 214Sep 2023: 158Oct 2023: 157Nov 2023: 150Dec 2023: 1362024Jan 2024: 169Feb 2024: 208Mar 2024: 169Apr 2024: 169May 2024: 196Jun 2024: 146Jul 2024: 204Aug 2024: 184Sep 2024: 186Oct 2024: 173Nov 2024: 193Dec 2024: 1942025Jan 2025: 215Feb 2025: 179Mar 2025: 198Apr 2025: 231May 2025: 241Jun 2025: 180Jul 2025: 229Aug 2025: 193Sep 2025: 171Oct 2025: 223Nov 2025: 170Dec 2025: 1832026Jan 2026: 254Feb 2026: 225Mar 2026: 215Apr 2026: 265May 2026: 251Jun 2026: 231

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

01,2072,4132016: 120162017: 132018: 78720182019: 1,5412020: 1,42020202021: 1,1852022: 1,44520222023: 1,7882024: 2,19120242025: 2,4132026: 1,4412026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Verzenio reports recording the termmedian drug in kinase inhibitor

  1. Diarrhoealoose or frequent stools34.3%4,877
  2. Fatiguetiredness13.8%1,958
  3. Nauseafeeling sick11.6%1,646
  4. Vomitingbeing sick5.2%745
  5. Decreased appetitereduced appetite4.5%643
  6. Drug ineffectivethe medicine did not work as expected4.3%611
  7. Deaththe patient died; cause not stated by this term4%562
  8. Astheniaweakness or lack of energy3.8%545
  9. Abdominal pain upperupper stomach pain3.8%534
  10. White blood cell count decreasedlow white cell count3.5%495
  11. Product dose omission issuea dose was missed3.4%478
  12. Constipationconstipation3.3%471
  13. Alopeciahair loss3.1%445
  14. Headachehead pain2.8%403
  15. Off label useused for a purpose or in a way not on the label2.8%402
  16. Dyspnoeashortness of breath2.7%390
  17. Painpain, site not specified2.7%389
  18. Dehydrationdehydration2.7%388
  19. Arthralgiajoint pain2.5%362
  20. Abdominal painstomach or belly pain2.2%313
  21. Dizzinesslight-headedness or unsteadiness2.2%311
  22. Weight decreasedweight loss2.2%311
  23. Anaemialow red blood cells2.1%299
  24. Neutropenialow neutrophils, a type of white blood cell2.1%295
  25. Rashskin rash2.1%294
  26. Abdominal discomfortstomach discomfort2%287
  27. Disease progressionthe disease advanced1.7%236
  28. Interstitial lung diseasescarring or inflammation of lung tissue1.6%232

Top 30 of 822 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

Death6%848
Life-threatening0.6%92
Hospitalisation (initial or prolonged)15.2%2,166
Disability0.3%49
Congenital anomaly0%2
Other serious17%2,425
Not serious64.9%9,229

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%1
2 to 110%4
12 to 170%0
18 to 445.4%775
45 to 6429.1%4,143
65 to 7413.6%1,940
75 and over8.4%1,190
Age not given43.4%6,172

Patient sex

Female87.5%12,452
Male1.6%228
Not given10.9%1,545

Who reported

Physician10.5%1,489
Pharmacist6.7%947
Other health professional16.2%2,303
Lawyer0%0
Consumer or non-health professional61.1%8,695
Not given5.6%791

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 88.2% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Breast cancer female4,37330.7%
Breast cancer3,51024.7%
Breast cancer metastatic9376.6%
Breast cancer recurrent2882%
Neoplasm malignant2511.8%
Breast cancer stage iv670.5%

The indication field is filled in by the reporter and is often blank; shares are of all 14,225 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Verzenio reports
Letrozole7575.3%
Faslodex4863.4%
Fulvestrant4203%
Anastrozole3872.7%
Ergocalciferol1951.4%
Amlodipine1320.9%
Gabapentin1320.9%
Loperamide1310.9%
Ondansetron1180.8%
Femara1170.8%

Other products listed in reports where Verzenio 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

MeasureVerzenioKinase inhibitorAll reports
Reports as suspect product14,225849,16120,646,523
Share of that pool—1.7%0.1%
Reports, latest 12 months2,610—1,332,454
Marked serious35.1%70.8%57.4%
Death recorded among outcomes, per 1,000 reports6019091
Hospitalisation recorded, per 1,000 reports152264213
Consumer-filed share61.1%42.3%45.8%
Top term, share of reportsDiarrhoea 34.3%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 Verzenio reports

How many adverse event reports has FDA received for Verzenio?

14,225 reports list Verzenio as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 2,610 of them arrived in the latest 12 months. Another 401 list it only as a concomitant medication.

What reactions are recorded in Verzenio reports?

diarrhoea (34.3%), fatigue (13.8%), nausea (11.6%), vomiting (5.2%) and decreased appetite (4.5%). 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 Verzenio was responsible.

How serious are the reports?

35.1% are marked serious by the reporter. Among the outcomes recorded, 6% of reports include death and 15.2% 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?

consumer or non-health professional (61.1%), other health professional (16.2%) and physician (10.5%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Verzenio rising?

2,610 reports in the 12 months to June 2026, up 10% from 2,378 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 Verzenio 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 Verzenio?

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 Verzenio as a suspect or interacting product; reports listing it only as a concomitant medication (401) 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.