Reported Reactions

Drugs › Kinase inhibitor

Brand name · Tucatinib

Tukysa: adverse event reports filed with FDA

4,482 reports list it as a suspect or interacting product, 2020–2026. Class: Kinase inhibitor. Also reported as Tukysa 150mg.

4,482
reports as suspect product
0% of all reports · about 727 a year
494
reports, 12 months to June 2026
1,157 in the 12 months before
50.8%
marked serious by the reporter
70.8% across the class
7.5%
record death among outcomes, as reported
337 reports · not verified by FDA

4,482 adverse event reports received by FDA list the brand name Tukysa (tucatinib) as a suspect or interacting product, from May 2020 to June 2026. A further 241 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, 494 reports listed it, down 57% from 1,157 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 727 reports a year and 0% of the 20,646,523 reports in the database, and 0.5% 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.

Reporters most often recorded diarrhoea (29.6%), fatigue (15.8%) and nausea (14.7%). A report can list several reactions, so shares add to more than 100%; 748 different terms appear across these reports. Diarrhoea is recorded in 29.6% of these reports, a larger share than in the median kinase inhibitor drug (6.9%).

50.8% of the reports are marked serious by the reporter (70.8% across the class); 7.5% record death among the outcomes and 16.8% record hospitalisation, as reported. 42.9% of the reports came from consumers, and the largest patient age group is 45 to 64 (22.4%). 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

0148296Jul 2021: 286Aug 2021: 27Sep 2021: 13Oct 2021: 16Nov 2021: 84Dec 2021: 312022Jan 2022: 36Feb 2022: 17Mar 2022: 26Apr 2022: 41May 2022: 27Jun 2022: 296Jul 2022: 28Aug 2022: 15Sep 2022: 22Oct 2022: 35Nov 2022: 54Dec 2022: 182023Jan 2023: 35Feb 2023: 38Mar 2023: 49Apr 2023: 51May 2023: 30Jun 2023: 38Jul 2023: 33Aug 2023: 22Sep 2023: 26Oct 2023: 23Nov 2023: 98Dec 2023: 302024Jan 2024: 45Feb 2024: 57Mar 2024: 25Apr 2024: 115May 2024: 27Jun 2024: 102Jul 2024: 289Aug 2024: 149Sep 2024: 143Oct 2024: 90Nov 2024: 90Dec 2024: 682025Jan 2025: 61Feb 2025: 78Mar 2025: 60Apr 2025: 72May 2025: 36Jun 2025: 21Jul 2025: 43Aug 2025: 28Sep 2025: 26Oct 2025: 19Nov 2025: 18Dec 2025: 182026Jan 2026: 63Feb 2026: 44Mar 2026: 66Apr 2026: 61May 2026: 47Jun 2026: 61

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

06001,2002020: 64020202021: 73220212022: 61520222023: 47320232024: 1,20020242025: 48020252026: 3422026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Tukysa reports recording the termmedian drug in kinase inhibitor

  1. Diarrhoealoose or frequent stools29.6%1,328
  2. Fatiguetiredness15.8%707
  3. Nauseafeeling sick14.7%659
  4. Vomitingbeing sick7.7%344
  5. Off label useused for a purpose or in a way not on the label7%312
  6. Product dose omission issuea dose was missed6%269
  7. Deaththe patient died; cause not stated by this term6%268
  8. Astheniaweakness or lack of energy5.4%240
  9. Decreased appetitereduced appetite5.2%235
  10. Headachehead pain3.9%176
  11. Disease progressionthe disease advanced3.8%169
  12. Rashskin rash3.7%167
  13. Constipationconstipation3.6%163
  14. Neuropathy peripheralnerve damage in hands or feet3.6%162
  15. Dehydrationdehydration3.5%156
  16. Pain in extremitypain in an arm or leg3.3%147
  17. Dizzinesslight-headedness or unsteadiness3.3%146
  18. Painpain, site not specified3.2%142
  19. Dry skindry skin3%133
  20. Hepatic enzyme increasedraised liver enzymes2.9%132
  21. Stomatitissore mouth2.8%125
  22. Drug interactionan interaction between medicines2.7%121
  23. Weight decreasedweight loss2.6%118
  24. Erythemaskin redness2.5%114
  25. Malaisegeneral feeling of being unwell2.5%114
  26. Arthralgiajoint pain2.5%113

Top 30 of 748 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

Death7.5%337
Life-threatening0.7%33
Hospitalisation (initial or prolonged)16.8%755
Disability0.4%17
Congenital anomaly0.1%3
Other serious36.5%1,636
Not serious49.2%2,204

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%0
12 to 170%1
18 to 447.9%355
45 to 6422.4%1,003
65 to 7411.4%509
75 and over5%226
Age not given53.3%2,387

Patient sex

Female89%3,988
Male3.9%175
Not given7.1%319

Who reported

Physician34.2%1,534
Pharmacist5.4%243
Other health professional17.1%768
Lawyer0%0
Consumer or non-health professional42.9%1,922
Not given0.3%15

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 77.5% 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 female1,38230.8%
Breast cancer metastatic49411%
Her2 positive breast cancer46610.4%
Breast cancer3527.9%
Neoplasm malignant2064.6%
Colon cancer370.8%

The indication field is filled in by the reporter and is often blank; shares are of all 4,482 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Tukysa reports
Capecitabine1,84541.2%
Trastuzumab95121.2%
Xeloda80417.9%
Herceptin78717.6%
Dexamethasone1112.5%
Pertuzumab982.2%
Zofran932.1%
Kadcyla902%
Eliquis791.8%
Loperamide751.7%

Other products listed in reports where Tukysa 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

MeasureTukysaKinase inhibitorAll reports
Reports as suspect product4,482849,16120,646,523
Share of that pool—0.5%0%
Reports, latest 12 months494—1,332,454
Marked serious50.8%70.8%57.4%
Death recorded among outcomes, per 1,000 reports7519091
Hospitalisation recorded, per 1,000 reports168264213
Consumer-filed share42.9%42.3%45.8%
Top term, share of reportsDiarrhoea 29.6%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 Tukysa reports

How many adverse event reports has FDA received for Tukysa?

4,482 reports list Tukysa as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 494 of them arrived in the latest 12 months. Another 241 list it only as a concomitant medication.

What reactions are recorded in Tukysa reports?

diarrhoea (29.6%), fatigue (15.8%), nausea (14.7%), vomiting (7.7%) and malignant neoplasm progression (7.3%). 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 Tukysa was responsible.

How serious are the reports?

50.8% are marked serious by the reporter. Among the outcomes recorded, 7.5% of reports include death and 16.8% 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?

consumer or non-health professional (42.9%), physician (34.2%) and other health professional (17.1%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Tukysa rising?

494 reports in the 12 months to June 2026, down 57% from 1,157 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 Tukysa 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 Tukysa?

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 Tukysa as a suspect or interacting product; reports listing it only as a concomitant medication (241) 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.