OpenClaim

Islelizumab Side Effects

The most commonly reported side effects of islelizumab include disease progression, off label use, and anaemia, based on 93 FDA adverse event reports from 2024 to 2025.

#1 Reported: Disease ProgressionAll side effects ↓Top Co-Medication: Tislelizumab-jsgrDrug interactions ↓58% of Reports Are AdultDemographics ↓

Islelizumab side effects

Percentages show how often each reaction appears relative to total reports for islelizumab.

1
Disease Progression33.3%31
2
Off Label Use19.4%18
3
Anaemia19.4%18
4
Thrombocytopenia18.3%17
5
Lymphadenopathy18.3%17
6
Malignant Neoplasm Progression12.9%12
7
Richter^s Syndrome10.8%10
8
Pneumonia8.6%8
9
Infusion Related Reaction6.5%6
10
Death6.5%6
11
Pyrexia6.5%6
12
C-reactive Protein Increased3.2%3
13
Infection3.2%3
14
Decreased Appetite3.2%3
15
Tumour Perforation3.2%3

These are voluntary reports and do not establish that islelizumab caused these reactions.

Report severity

97.8%Serious91 reports
28.0%Hospitalizations26 reports
18.3%Fatal17 reports

Seriousness is determined by the reporter, not by OpenClaim.

Islelizumab drug interactions

Other drugs that appear in adverse event reports alongside islelizumab. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Tislelizumab-jsgr100.0%93
2
Zanubrutinib20.4%19
3
Cyclophosphamide18.3%17
4
Bendamustine-hydrochloride18.3%17
5
Fludarabine-phosphate18.3%17
6
Ibrutinib18.3%17
7
Prednisolone18.3%17
8
Venetoclax18.3%17
9
Vincristine-sulfate18.3%17
10
Doxorubicin-hydrochloride17.2%16
11
Lenalidomide16.1%15
12
Rituximab15.1%14
13
Oxaliplatin12.9%12
14
Fluorouracil11.8%11
15
Cisplatin7.5%7

Taken alongside

1
Omeprazole9.7%9
2
Sodium-chloride8.6%8
3
Aminophylline7.5%7
4
Dexamethasone7.5%7
5
Celecoxib7.5%7
6
Morphine-sulfate7.5%7
7
Pregabalin7.5%7
8
Acetaminophen7.5%7
9
Polyethylene-glycol-33507.5%7
10
Potassium-chloride7.5%7
11
Sodium-bicarbonate7.5%7
12
Aluminum-hydroxide6.5%6
13
Magnesium-trisilicate6.5%6
14
Cyanocobalamin6.5%6
15
Cisplatin6.5%6

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports islelizumab side effects

12.9% of islelizumab adverse event reports involve female patients and 39.8% involve male patients. The largest age group is adult at 58%. These figures reflect who reports side effects, not underlying risk.

Sex

Female12.9%
Male39.8%
Unknown47.3%

Age group

< 20.0%
2–110.0%
12–170.0%
18–6458.3%
65+41.7%

What is islelizumab used for

Conditions and purposes for which patients were taking islelizumab when the adverse event was reported.

Chronic Lymphocytic LeukaemiaColon CancerDiffuse Large B-cell LymphomaGastric CancerGastrooesophageal CancerGastrooesophageal Reflux DiseaseLeukaemia RecurrentLung Neoplasm MalignantLymphomaMetastases To BoneMetastases To LungMetastases To Lymph NodesMetastases To SkinNasopharyngeal CancerNasopharyngeal Cancer Metastatic

Showing 15 of 26 indications

Islelizumab brand names and reporting trend

Quarterly reports (2024–2025)

20242025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking islelizumab with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.

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