Generic name
Anti-thymocyte globulin (rabbit): adverse event reports filed with FDA
1,982 reports list it as a suspect or interacting product, 2004–2026. Class: Immunoglobulin G. Also reported as Anti-Thymocyte Globulin Nos.
- 1,982
- reports as suspect product
- 0% of all reports · about 90 a year
- 260
- reports, 12 months to June 2026
- 166 in the 12 months before
- 98.8%
- marked serious by the reporter
- 97.1% across the class
- 32.6%
- record death among outcomes, as reported
- 646 reports · not verified by FDA
1,982 adverse event reports received by FDA list anti-thymocyte globulin (rabbit), a generic name as a suspect or interacting product, from July 2004 to June 2026. A further 619 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, 260 reports listed it, up 57% from 166 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 90 reports a year and 0% of the 20,646,523 reports in the database, and 22.3% of the reports for the immunoglobulin G class. How many people take it is not in the data, so a count is not a rate of occurrence.
The MedDRA terms listed most often are off label use (15.3%), pyrexia (10.3%) and cytomegalovirus infection (7.3%). A report can list several reactions, so shares add to more than 100%; 640 different terms appear across these reports. Off label use is recorded in 15.3% of these reports, a larger share than in the median immunoglobulin G drug (6.3%).
98.8% of the reports are marked serious by the reporter (97.1% across the class); 32.6% record death among the outcomes and 28.4% record hospitalisation, as reported. 60.9% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (20.8%). 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 Anti-thymocyte globulin (rabbit) reports recording the termmedian drug in immunoglobulin g
- Off label useused for a purpose or in a way not on the label15.3%304
- Pyrexiafever10.3%205
- Cytomegalovirus infection7.3%145
- Cytomegalovirus infection reactivation5.5%109
- Mucosal inflammation5.5%109
- Post transplant lymphoproliferative disorder5.3%105
- Pneumonialung infection4.7%94
- Sepsisa severe body-wide response to infection4.6%92
- Multiple organ dysfunction syndromeseveral organs failing4.2%84
- Transplant rejection3.8%76
- Acute graft versus host disease3.8%75
- Drug ineffectivethe medicine did not work as expected3.7%73
- BK virus infection3.5%69
- Cytomegalovirus viraemia3.4%68
- Cystitis haemorrhagic3.4%67
- Acute kidney injurysudden loss of kidney function3.3%65
- Deaththe patient died; cause not stated by this term3.3%65
- Pancytopenialow counts of all blood cells3.2%64
- Diarrhoealoose or frequent stools3.1%62
- Product use in unapproved indicationused for a purpose not on the label2.7%54
- Chronic graft versus host disease2.7%53
- Adenovirus infection2.6%51
- Septic shockshock arising from infection2.6%51
- Dyspnoeashortness of breath2.5%50
- Respiratory failurethe lungs could not supply enough oxygen2.4%48
- Neutropenialow neutrophils, a type of white blood cell2.4%47
- Pleural effusionfluid around the lung2.3%46
- Venoocclusive liver disease2.2%44
- Acute graft versus host disease in skin2.2%43
Top 30 of 640 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 3 drugs in the immunoglobulin g 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 8,877 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. 27.8% of reports give the United States as the country of the event or reporter.
Reason for use recorded
| Indication as recorded (MedDRA) | Reports | Share |
|---|---|---|
| Bone marrow conditioning regimen | 400 | 20.2% |
| Immunosuppressant drug therapy | 227 | 11.5% |
| Immunosuppression | 167 | 8.4% |
| Prophylaxis against graft versus host disease | 142 | 7.2% |
| Prophylaxis against transplant rejection | 99 | 5% |
| Stem cell transplant | 57 | 2.9% |
The indication field is filled in by the reporter and is often blank; shares are of all 1,982 reports.
In context
| Measure | Anti-thymocyte globulin (rabbit) | Immunoglobulin G | All reports |
|---|---|---|---|
| Reports as suspect product | 1,982 | 8,877 | 20,646,523 |
| Share of that pool | — | 22.3% | 0% |
| Reports, latest 12 months | 260 | — | 1,332,454 |
| Marked serious | 98.8% | 97.1% | 57.4% |
| Death recorded among outcomes, per 1,000 reports | 326 | 279 | 91 |
| Hospitalisation recorded, per 1,000 reports | 284 | 346 | 213 |
| Consumer-filed share | 1.8% | 4.4% | 45.8% |
| Top term, share of reports | Off label use 15.3% | median 6.3% | 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 immunoglobulin g class
| Drug | Name type | Reports | Latest 12 months | Marked serious |
|---|---|---|---|---|
| Thymoglobulin | brand | 6,283 | 308 | 97% |
| Atgam | brand | 612 | 33 | 93.6% |
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 Anti-thymocyte globulin (rabbit) reports
How many adverse event reports has FDA received for Anti-thymocyte globulin (rabbit)?
1,982 reports list Anti-thymocyte globulin (rabbit) as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 260 of them arrived in the latest 12 months. Another 619 list it only as a concomitant medication.
What reactions are recorded in Anti-thymocyte globulin (rabbit) reports?
off label use (15.3%), pyrexia (10.3%), cytomegalovirus infection (7.3%), cytomegalovirus infection reactivation (5.5%) and mucosal inflammation (5.5%). 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 Anti-thymocyte globulin (rabbit) was responsible.
How serious are the reports?
98.8% are marked serious by the reporter. Among the outcomes recorded, 32.6% of reports include death and 28.4% 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?
other health professional (60.9%), physician (32.9%) and not given (2.6%). Most reports reach FDA through the manufacturer, which must forward reports it receives.
Are reports for Anti-thymocyte globulin (rabbit) rising?
260 reports in the 12 months to June 2026, up 57% from 166 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 Anti-thymocyte globulin (rabbit) 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 Anti-thymocyte globulin (rabbit)?
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 Anti-thymocyte globulin (rabbit) as a suspect or interacting product; reports listing it only as a concomitant medication (619) 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.