Drugs › CTLA-4-directed blocking antibody
Brand name · Tremelimumab
Imjudo: adverse event reports filed with FDA
1,729 reports list it as a suspect or interacting product, 2020–2026. Class: CTLA-4-directed blocking antibody.
- 1,729
- reports as suspect product
- 0% of all reports · about 297 a year
- 692
- reports, 12 months to June 2026
- 380 in the 12 months before
- 94.3%
- marked serious by the reporter
- 89.7% across the class
- 30.2%
- record death among outcomes, as reported
- 522 reports · not verified by FDA
Between September 2020 and June 2026, 1,729 adverse event reports received by FDA list the brand name Imjudo (tremelimumab) as a suspect or interacting product. Reports that mention it only as a concomitant medication (10) are left out of every figure here.
In the 12 months to June 2026, 692 reports listed it, up 82% from 380 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 297 reports a year and 0% of the 20,646,523 reports in the database, and 3.8% 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.
The reactions recorded most often are death (11.2%), malignant neoplasm progression (10.9%) and diarrhoea (8.3%). A report can list several reactions, so shares add to more than 100%; 328 different terms appear across these reports. Death is recorded in 11.2% of these reports, about the same share as in the median CTLA-4-directed blocking antibody drug (9.3%).
94.3% of the reports are marked serious by the reporter (89.7% across the class); 30.2% record death among the outcomes and 33.7% record hospitalisation, as reported. 83.5% of the reports came from physicians, and the largest patient age group is 65 to 74 (24.6%). 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
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
2026 covers reports received through June 2026 only.
Reactions recorded in the reports
share of Imjudo reports recording the termmedian drug in ctla-4-directed blocking antibody
- Deaththe patient died; cause not stated by this term11.2%194
- Malignant neoplasm progression10.9%188
- Diarrhoealoose or frequent stools8.3%144
- Cytokine release syndrome7.2%124
- Immune-mediated enterocolitis5.3%92
- Pyrexiafever5.3%91
- Liver disorder4.9%84
- Rashskin rash4.5%78
- Immune-mediated hepatic disorder4.2%73
- Colitisinflamed bowel3.8%66
- Interstitial lung diseasescarring or inflammation of lung tissue2.9%50
- Malaisegeneral feeling of being unwell2.8%48
- Adrenal insufficiencythe adrenal glands produce too little hormone2.4%42
- Decreased appetitereduced appetite2.4%42
- Myocarditisinflammation of the heart muscle2.3%39
- Pneumonialung infection2%34
- Platelet count decreasedlow platelet count1.9%32
- Pruritusitching1.9%32
- Enterocolitis1.7%29
- Immune-mediated dermatitis1.6%27
- Acute kidney injurysudden loss of kidney function1.5%26
- Febrile neutropeniafever with low white blood cells1.5%26
- Anaemialow red blood cells1.4%24
- Nauseafeeling sick1.4%24
- Cholangitis1.3%23
- Hepatic failureliver failure1.3%23
- Liver carcinoma ruptured1.3%23
- Renal disorder1.3%23
Top 30 of 328 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
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
Patient sex
Who reported
Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 11.7% of reports give the United States as the country of the event or reporter.
Reason for use recorded
| Indication as recorded (MedDRA) | Reports | Share |
|---|---|---|
| Hepatocellular carcinoma | 926 | 53.6% |
| Non-small cell lung cancer | 454 | 26.3% |
| Hepatic cancer | 18 | 1% |
| Non-small cell lung cancer stage iv | 18 | 1% |
| Lung neoplasm malignant | 15 | 0.9% |
| Lung adenocarcinoma | 5 | 0.3% |
The indication field is filled in by the reporter and is often blank; shares are of all 1,729 reports.
In context
| Measure | Imjudo | CTLA-4-directed blocking antibody | All reports |
|---|---|---|---|
| Reports as suspect product | 1,729 | 45,770 | 20,646,523 |
| Share of that pool | — | 3.8% | 0% |
| Reports, latest 12 months | 692 | — | 1,332,454 |
| Marked serious | 94.3% | 89.7% | 57.4% |
| Death recorded among outcomes, per 1,000 reports | 302 | 229 | 91 |
| Hospitalisation recorded, per 1,000 reports | 337 | 458 | 213 |
| Consumer-filed share | 6.1% | 18.6% | 45.8% |
| Top term, share of reports | Death 11.2% | median 9.3% | 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 ctla-4-directed blocking antibody class
| Drug | Name type | Reports | Latest 12 months | Marked serious |
|---|---|---|---|---|
| Yervoy | brand | 22,109 | 1,918 | 81.5% |
| Ipilimumab | generic | 19,614 | 792 | 97.3% |
| Tremelimumab | generic | 2,318 | 351 | 99% |
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 Imjudo reports
How many adverse event reports has FDA received for Imjudo?
1,729 reports list Imjudo as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 692 of them arrived in the latest 12 months. Another 10 list it only as a concomitant medication.
What reactions are recorded in Imjudo reports?
death (11.2%), malignant neoplasm progression (10.9%), diarrhoea (8.3%), cytokine release syndrome (7.2%) and immune-mediated enterocolitis (5.3%). 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 Imjudo was responsible.
How serious are the reports?
94.3% are marked serious by the reporter. Among the outcomes recorded, 30.2% of reports include death and 33.7% 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 (83.5%), consumer or non-health professional (6.1%) and other health professional (5.7%). Most reports reach FDA through the manufacturer, which must forward reports it receives.
Are reports for Imjudo rising?
692 reports in the 12 months to June 2026, up 82% from 380 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 Imjudo 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 Imjudo?
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 Imjudo as a suspect or interacting product; reports listing it only as a concomitant medication (10) 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.