Reported Reactions

Drugs › Kinase inhibitor

Brand name · Erdafitinib

Balversa: adverse event reports filed with FDA

662 reports list it as a suspect or interacting product, 2019–2026. Class: Kinase inhibitor.

662
reports as suspect product
0% of all reports · about 97 a year
100
reports, 12 months to June 2026
73 in the 12 months before
64.4%
marked serious by the reporter
70.8% across the class
29.8%
record death among outcomes, as reported
197 reports · not verified by FDA

Between September 2019 and June 2026, 662 adverse event reports received by FDA list the brand name Balversa (erdafitinib) as a suspect or interacting product. Reports that mention it only as a concomitant medication (7) are left out of every figure here.

In the 12 months to June 2026, 100 reports listed it, up 37% from 73 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 97 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 death (25.2%), off label use (10.6%) and diarrhoea (8.6%). A report can list several reactions, so shares add to more than 100%; 153 different terms appear across these reports. Death is recorded in 25.2% of these reports, a larger share than in the median kinase inhibitor drug (7.6%).

64.4% of the reports are marked serious by the reporter (70.8% across the class); 29.8% record death among the outcomes and 13.4% record hospitalisation, as reported. 45% of the reports came from consumers, and the largest patient age group is 75 and over (15.7%). 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

01224Jul 2021: 12Aug 2021: 10Sep 2021: 4Oct 2021: 12Nov 2021: 10Dec 2021: 182022Jan 2022: 17Feb 2022: 14Mar 2022: 24Apr 2022: 14May 2022: 10Jun 2022: 10Jul 2022: 15Aug 2022: 8Sep 2022: 10Oct 2022: 12Nov 2022: 18Dec 2022: 222023Jan 2023: 9Feb 2023: 3Mar 2023: 5Apr 2023: 4May 2023: 6Jun 2023: 6Jul 2023: 8Aug 2023: 6Sep 2023: 6Oct 2023: 10Nov 2023: 3Dec 2023: 72024Jan 2024: 7Feb 2024: 7Mar 2024: 7Apr 2024: 9May 2024: 13Jun 2024: 11Jul 2024: 10Aug 2024: 4Sep 2024: 11Oct 2024: 5Nov 2024: 7Dec 2024: 62025Jan 2025: 3Feb 2025: 4Mar 2025: 3Apr 2025: 8May 2025: 8Jun 2025: 4Jul 2025: 2Aug 2025: 8Sep 2025: 13Oct 2025: 8Nov 2025: 5Dec 2025: 132026Jan 2026: 4Feb 2026: 11Mar 2026: 13Apr 2026: 11May 2026: 5Jun 2026: 7

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

0871742019: 320192020: 4120202021: 14420212022: 17420222023: 7320232024: 9720242025: 7920252026: 512026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Balversa reports recording the termmedian drug in kinase inhibitor

  1. Deaththe patient died; cause not stated by this term25.2%167
  2. Off label useused for a purpose or in a way not on the label10.6%70
  3. Diarrhoealoose or frequent stools8.6%57
  4. Stomatitissore mouth8%53
  5. Dry mouthdry mouth5.1%34
  6. Fatiguetiredness4.8%32
  7. Nail discolouration4.7%31
  8. Onycholysis4.5%30
  9. Pain in extremitypain in an arm or leg4.4%29
  10. Hyperphosphataemia4.2%28
  11. Onychomadesis4.2%28
  12. Dry eyedry eye3.5%23
  13. Dry skindry skin3.3%22
  14. Adverse drug reactiona harmful or unpleasant reaction reported to a medicine2.9%19
  15. Decreased appetitereduced appetite2.7%18
  16. Weight decreasedweight loss2.7%18
  17. Alopeciahair loss2.6%17
  18. Neuropathy peripheralnerve damage in hands or feet2.6%17
  19. Blood phosphorus increased2.1%14
  20. Nauseafeeling sick2.1%14
  21. Product use in unapproved indicationused for a purpose not on the label2.1%14
  22. Retinal detachmentthe retina separated from the back of the eye2.1%14
  23. Urinary tract infectionbladder or urinary infection2.1%14
  24. Adverse eventan unwanted medical event, type not specified2%13
  25. Cataractclouding of the eye lens2%13
  26. Product dose omission issuea dose was missed2%13
  27. Constipationconstipation1.8%12

Top 30 of 153 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

Death29.8%197
Life-threatening0.5%3
Hospitalisation (initial or prolonged)13.4%89
Disability0.3%2
Congenital anomaly0%0
Other serious28.1%186
Not serious35.6%236

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 110.2%1
12 to 170.9%6
18 to 442%13
45 to 648%53
65 to 7413.7%91
75 and over15.7%104
Age not given59.5%394

Patient sex

Female27.6%183
Male53%351
Not given19.3%128

Who reported

Physician22.8%151
Pharmacist9.1%60
Other health professional22.4%148
Lawyer0%0
Consumer or non-health professional45%298
Not given0.8%5

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 81.1% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Transitional cell carcinoma619.2%
Bladder cancer568.5%
Transitional cell carcinoma metastatic203%
Metastatic carcinoma of the bladder91.4%
Urethral cancer71.1%
Brain neoplasm malignant50.8%

The indication field is filled in by the reporter and is often blank; shares are of all 662 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Balversa reports
Gabapentin101.5%
Paclitaxel91.4%
Prednisone91.4%
Pregabalin91.4%
Eliquis81.2%
Enfortumab vedotin81.2%
Imodium81.2%
Aspirin71.1%
Keytruda71.1%
Duloxetine hydrochloride50.8%

Other products listed in reports where Balversa 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

MeasureBalversaKinase inhibitorAll reports
Reports as suspect product662849,16120,646,523
Share of that pool—0.1%0%
Reports, latest 12 months100—1,332,454
Marked serious64.4%70.8%57.4%
Death recorded among outcomes, per 1,000 reports29819091
Hospitalisation recorded, per 1,000 reports134264213
Consumer-filed share45%42.3%45.8%
Top term, share of reportsDeath 25.2%median 7.6%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 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 Balversa reports

How many adverse event reports has FDA received for Balversa?

662 reports list Balversa as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 100 of them arrived in the latest 12 months. Another 7 list it only as a concomitant medication.

What reactions are recorded in Balversa reports?

death (25.2%), off label use (10.6%), diarrhoea (8.6%), stomatitis (8%) and nail disorder (5.7%). 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 Balversa was responsible.

How serious are the reports?

64.4% are marked serious by the reporter. Among the outcomes recorded, 29.8% of reports include death and 13.4% 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 (45%), physician (22.8%) and other health professional (22.4%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Balversa rising?

100 reports in the 12 months to June 2026, up 37% from 73 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 Balversa 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 Balversa?

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 Balversa as a suspect or interacting product; reports listing it only as a concomitant medication (7) 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.