Reported Reactions

Drugs › CTLA-4-directed blocking antibody

Generic name

Ipilimumab: adverse event reports filed with FDA

19,614 reports list it as a suspect or interacting product, 2006–2026. Class: CTLA-4-directed blocking antibody.

19,614
reports as suspect product
0.1% of all reports · about 993 a year
792
reports, 12 months to June 2026
1,035 in the 12 months before
97.3%
marked serious by the reporter
89.7% across the class
19.3%
record death among outcomes, as reported
3,779 reports · not verified by FDA

19,614 adverse event reports received by FDA list ipilimumab, a generic name as a suspect or interacting product, from October 2006 to June 2026. A further 1,018 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, 792 reports listed it, down 23% from 1,035 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 993 reports a year and 0.1% of the 20,646,523 reports in the database, and 42.9% of the reports for the CTLA-4-directed blocking antibody class. How many people take it is not in the data, so a count is not a rate of occurrence.

Reporters most often recorded malignant neoplasm progression (8.5%), diarrhoea (7.6%) and colitis (6.7%). A report can list several reactions, so shares add to more than 100%; 1,493 different terms appear across these reports. Malignant neoplasm progression is recorded in 8.5% of these reports, about the same share as in the median CTLA-4-directed blocking antibody drug (8.9%).

97.3% of the reports are marked serious by the reporter (89.7% across the class); 19.3% record death among the outcomes and 59% record hospitalisation, as reported. 58.1% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (34.5%). 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

0108215Jul 2021: 173Aug 2021: 187Sep 2021: 182Oct 2021: 207Nov 2021: 174Dec 2021: 2152022Jan 2022: 163Feb 2022: 165Mar 2022: 144Apr 2022: 138May 2022: 169Jun 2022: 150Jul 2022: 132Aug 2022: 154Sep 2022: 131Oct 2022: 145Nov 2022: 122Dec 2022: 1252023Jan 2023: 69Feb 2023: 66Mar 2023: 106Apr 2023: 86May 2023: 98Jun 2023: 150Jul 2023: 77Aug 2023: 94Sep 2023: 60Oct 2023: 76Nov 2023: 108Dec 2023: 1122024Jan 2024: 67Feb 2024: 101Mar 2024: 144Apr 2024: 60May 2024: 78Jun 2024: 69Jul 2024: 111Aug 2024: 97Sep 2024: 152Oct 2024: 132Nov 2024: 71Dec 2024: 742025Jan 2025: 81Feb 2025: 63Mar 2025: 69Apr 2025: 67May 2025: 58Jun 2025: 60Jul 2025: 10Aug 2025: 20Sep 2025: 34Oct 2025: 34Nov 2025: 92Dec 2025: 672026Jan 2026: 56Feb 2026: 62Mar 2026: 80Apr 2026: 80May 2026: 107Jun 2026: 150

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

01,1872,3742006: 420062007: 42008: 62009: 1020092010: 202011: 3352012: 38320122013: 4232014: 6852015: 1,31320152016: 9462017: 1,7452018: 2,11620182019: 2,3742020: 1,9902021: 2,07420212022: 1,7382023: 1,1022024: 1,15620242025: 6552026: 535

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Ipilimumab reports recording the termmedian drug in ctla-4-directed blocking antibody

  1. Diarrhoealoose or frequent stools7.6%1,500
  2. Colitisinflamed bowel6.7%1,322
  3. Deaththe patient died; cause not stated by this term5%986
  4. Pyrexiafever4.8%951
  5. Fatiguetiredness4.1%803
  6. Nauseafeeling sick3.7%716
  7. Immune-mediated enterocolitis3.4%674
  8. Off label useused for a purpose or in a way not on the label3.3%639
  9. Hypophysitis3.2%630
  10. Vomitingbeing sick3.1%614
  11. Rashskin rash3.1%600
  12. Dyspnoeashortness of breath3%593
  13. Acute kidney injurysudden loss of kidney function3%587
  14. Pneumonialung infection2.9%574
  15. Adrenal insufficiencythe adrenal glands produce too little hormone2.4%475
  16. Decreased appetitereduced appetite2.4%463
  17. Dehydrationdehydration2.3%460
  18. Anaemialow red blood cells2.3%443
  19. Sepsisa severe body-wide response to infection2.1%418
  20. Hypothyroidismunderactive thyroid2.1%409
  21. Hyponatraemialow blood sodium2%388
  22. Astheniaweakness or lack of energy1.9%379
  23. Hepatitis1.9%371
  24. Drug ineffectivethe medicine did not work as expected1.8%357
  25. Headachehead pain1.8%347
  26. Intentional product use issuedeliberate use not as intended1.7%338
  27. Pruritusitching1.7%331
  28. Immune-mediated hepatitis1.7%330

Top 30 of 1,493 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 4 drugs in the ctla-4-directed blocking antibody 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

Death19.3%3,779
Life-threatening8.6%1,685
Hospitalisation (initial or prolonged)59%11,577
Disability1.6%311
Congenital anomaly0%5
Other serious75.7%14,843
Not serious2.7%531

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 45,770 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%8
2 to 110.1%24
12 to 170.2%38
18 to 448.7%1,711
45 to 6434.5%6,765
65 to 7426%5,102
75 and over12.5%2,445
Age not given18%3,521

Patient sex

Female32.5%6,376
Male56.2%11,030
Not given11.3%2,208

Who reported

Physician26.4%5,175
Pharmacist1.8%353
Other health professional58.1%11,396
Lawyer0%1
Consumer or non-health professional13.3%2,607
Not given0.4%82

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 44% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Malignant melanoma5,08425.9%
Metastatic malignant melanoma2,86514.6%
Non-small cell lung cancer1,4497.4%
Renal cell carcinoma1,3987.1%
Metastatic renal cell carcinoma5372.7%
Small cell lung cancer2421.2%

The indication field is filled in by the reporter and is often blank; shares are of all 19,614 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Ipilimumab reports
Nivolumab13,97171.2%
Carboplatin1,2536.4%
Prednisone1,0205.2%
Pembrolizumab7153.6%
Pantoprazole6173.1%
Paclitaxel6003.1%
Omeprazole5903%
Acetaminophen5823%
Prednisolone5602.9%
Aspirin5182.6%

Other products listed in reports where Ipilimumab 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

MeasureIpilimumabCTLA-4-directed blocking antibodyAll reports
Reports as suspect product19,61445,77020,646,523
Share of that pool—42.9%0.1%
Reports, latest 12 months792—1,332,454
Marked serious97.3%89.7%57.4%
Death recorded among outcomes, per 1,000 reports19322991
Hospitalisation recorded, per 1,000 reports590458213
Consumer-filed share13.3%18.6%45.8%
Top term, share of reportsMalignant neoplasm progression 8.5%median 8.9%0.5%

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 ctla-4-directed blocking antibody class

DrugName typeReportsLatest 12 monthsMarked serious
Yervoybrand22,1091,91881.5%
Tremelimumabgeneric2,31835199%
Imjudobrand1,72969294.3%

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 Ipilimumab reports

How many adverse event reports has FDA received for Ipilimumab?

19,614 reports list Ipilimumab as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 792 of them arrived in the latest 12 months. Another 1,018 list it only as a concomitant medication.

What reactions are recorded in Ipilimumab reports?

malignant neoplasm progression (8.5%), diarrhoea (7.6%), colitis (6.7%), death (5%) and pyrexia (4.8%). 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 Ipilimumab was responsible.

How serious are the reports?

97.3% are marked serious by the reporter. Among the outcomes recorded, 19.3% of reports include death and 59% 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 (58.1%), physician (26.4%) and consumer or non-health professional (13.3%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Ipilimumab rising?

792 reports in the 12 months to June 2026, down 23% from 1,035 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 Ipilimumab 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 Ipilimumab?

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 Ipilimumab as a suspect or interacting product; reports listing it only as a concomitant medication (1,018) 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.