Drug · FAERS side-effect profile with label screen
Blinatumomab side effects: what 10,373 FDA adverse event reports show
Drug class
Bispecific cd19-directed cd3 t-cell engager
FDA label, Indications wording
Brand names
Blincyto
openFDA label
Who reports
10,373 reports · 80% serious · 1,893 with death outcome · 47% female
openFDA FAERS counts, all years, deduplication not applied
Used for
BLINCYTO is a bispecific CD19-directed CD3 T-cell engager indicated for the treatment of adult and pediatric patients one month and older with: CD19-positive B-cell precursor acute lymphoblastic leukemia (ALL) in first or second complete remission with minimal residual disease (MRD) greater than or equal to 0.1%. ( 1.1 ) Relapsed or refractory CD19-positive B-cell precursor acute lymphoblastic leukemia (ALL).
FDA label, Indications and Usage
What it is
Blinatumomab is a bispecific CD19-directed CD3 T-cell engager. Blinatumomab is produced in Chinese hamster ovary cells. It consists of 504 amino acids and has a molecular weight of approximately 54 kilodaltons. Each BLINCYTO package contains one vial BLINCYTO and one vial IV Solution Stabilizer.
FDA label, Description section
Boxed warning
CYTOKINE RELEASE SYNDROME and NEUROLOGICAL TOXICITIES including IMMUNE EFFECTOR CELL-ASSOCIATED NEUROTOXICITY SYNDROME Cytokine Release Syndrome (CRS), which may be life-threatening or fatal, occurred in patients receiving BLINCYTO.
FDA label
How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation.
Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)?
That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.
Causality screen of the 40 strongest signals
Labeled — boxed warning 3Labeled (related wording) 1Likely indication confounding 18Reporting / coding artifact 1Lab value / disease marker 2Not in label — unassessed 15
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 960 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Leukaemic infiltration extramedullary | 185 | 6,147.7 4,597.6–8,220.6ROR 6,259.4 · χ² 276,939 / p <1e-300 | 1,301.6 EB05 1,151.6 · IC025 +8.0 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=185 · 98% clinician | no trial data cached |
| Lineage switch leukaemia | 34 | 3,987.7 2,228.5–7,135.7ROR 4,000.8 · χ² 43,852 / p <1e-300 | 758.1 EB05 567.4 · IC025 +5.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=34 · 100% clinician | no trial data cached |
| Acute lymphocytic leukaemia refractory | 84 | 3,418.0 2,404.3–4,859.2ROR 3,445.9 · χ² 104,463 / p <1e-300 | 977.0 EB05 813.9 · IC025 +6.9 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=84 · 99% clinician | no trial data cached |
| Precursor b-lymphoblastic lymphoma recurrent | 15 | 2,300.6 1,095.0–4,833.8ROR 2,303.9 · χ² 14,958 / p <1e-300 | 451.2 EB05 290.2 · IC025 +4.0 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=15 | no trial data cached |
| Central nervous system leukaemia | 191 | 2,069.7 1,691.9–2,531.9ROR 2,108.5 · χ² 192,770 / p <1e-300 | 921.4 EB05 816.9 · IC025 +7.9 3/3 methods agree | Labeled (related wording) related wording | serious n=191 · 98% clinician | no trial data cached |
| Leukaemic infiltration renal | 11 | 1,687.1 756.0–3,765.0ROR 1,688.9 · χ² 9,147 / p <1e-300 | 352.7 EB05 210.1 · IC025 +3.5 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=11 | no trial data cached |
| B precursor type acute leukaemia | 168 | 1,550.8 1,268.8–1,895.5ROR 1,576.3 · χ² 145,492 / p <1e-300 | 793.3 EB05 697.6 · IC025 +7.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=168 · 95% clinician | no trial data cached |
| Acute lymphocytic leukaemia recurrent | 1,092 | 1,494.4 1,384.9–1,612.5ROR 1,670.1 · χ² 930,774 / p <1e-300 | 841.9 EB05 800.8 · IC025 +9.2 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=1,090 · 97% clinician | no trial data cached |
| Bone marrow leukaemic cell infiltration | 31 | 1,261.4 804.8–1,977.1ROR 1,265.2 · χ² 23,147 / p <1e-300 | 522.4 EB05 385.5 · IC025 +5.3 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=31 · 94% clinician | no trial data cached |
| Minimal residual disease | 99 | 542.3 434.6–676.6ROR 547.5 · χ² 41,628 / p <1e-300 | 394.0 EB05 333.0 · IC025 +6.8 3/3 methods agree | Likely indication confounding term in indications | serious n=99 | no trial data cached |
| B-cell type acute leukaemia | 134 | 464.7 385.4–560.2ROR 470.7 · χ² 49,905 / p <1e-300 | 357.7 EB05 309.7 · IC025 +7.0 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=134 · 99% clinician | no trial data cached |
| Csf lymphocyte count increased | 11 | 438.6 228.4–842.3ROR 439.1 · χ² 3,586 / p <1e-300 | 221.7 EB05 132.1 · IC025 +3.4 3/3 methods agree | Lab value / disease marker | serious n=11 | no trial data cached |
| Acute biphenotypic leukaemia | 15 | 404.2 232.1–703.8ROR 404.7 · χ² 4,686 / p <1e-300 | 235.6 EB05 151.5 · IC025 +4.0 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=15 | no trial data cached |
| B-cell aplasia | 31 | 281.0 193.0–409.0ROR 281.8 · χ² 7,336 / p <1e-300 | 214.0 EB05 157.9 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious n=31 · ♀ 23% (drug 47%) | no trial data cached |
| Aspiration bone marrow abnormal | 16 | 270.4 160.4–455.6ROR 270.8 · χ² 3,547 / p <1e-300 | 185.7 EB05 121.2 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=16 | no trial data cached |
| Csf cell count increased | 17 | 260.7 157.3–432.1ROR 261.2 · χ² 3,663 / p <1e-300 | 183.5 EB05 121.3 · IC025 +4.1 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious n=17 | no trial data cached |
| Blast cell count increased | 114 | 246.3 202.9–298.9ROR 249.0 · χ² 24,568 / p <1e-300 | 211.6 EB05 180.9 · IC025 +6.5 3/3 methods agree | Likely indication confounding term in indications | serious n=113 · 93% clinician | no trial data cached |
| Leukaemia cutis | 15 | 216.7 127.2–369.1ROR 217.0 · χ² 2,714 / p <1e-300 | 156.9 EB05 100.9 · IC025 +3.9 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=15 | no trial data cached |
| Transplantation complication | 38 | 203.1 145.6–283.5ROR 203.9 · χ² 6,754 / p <1e-300 | 168.9 EB05 128.5 · IC025 +5.2 3/3 methods agree | Reporting / coding artifact | serious n=38 · 97% clinician | no trial data cached |
| Acute lymphocytic leukaemia | 247 | 193.2 169.8–219.9ROR 197.9 · χ² 42,888 / p <1e-300 | 173.9 EB05 156.4 · IC025 +6.8 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=244 · 93% clinician | no trial data cached |
| Transformation to acute myeloid leukaemia | 55 | 184.6 140.1–243.2ROR 185.6 · χ² 9,026 / p <1e-300 | 159.8 EB05 127.4 · IC025 +5.6 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=55 · 100% clinician | no trial data cached |
| Metastases to retroperitoneum | 12 | 153.4 85.3–275.8ROR 153.6 · χ² 1,548 / p <1e-300 | 116.6 EB05 71.1 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Metastases to muscle | 12 | 145.0 80.7–260.5ROR 145.2 · χ² 1,468 / p <1e-300 | 111.7 EB05 68.1 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Cytokine release syndrome | 1,095 | 123.3 116.3–130.6ROR 137.7 · χ² 125,082 / p <1e-300 | 115.9 EB05 110.3 · IC025 +6.7 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 84.5 · 96% clinician | no trial data cached |
| Blast cells present | 26 | 116.0 78.1–172.1ROR 116.3 · χ² 2,693 / p <1e-300 | 101.7 EB05 72.9 · IC025 +4.5 3/3 methods agree | Lab value / disease marker | serious n=22 · ♀ 20% (drug 47%) | no trial data cached |
| Babesiosis | 15 | 114.2 67.9–192.0ROR 114.3 · χ² 1,486 / p <1e-300 | 95.3 EB05 61.3 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious n=15 | no trial data cached |
| Spontaneous bacterial peritonitis | 11 | 95.4 52.1–174.6ROR 95.5 · χ² 892 / p 2e-196 | 79.0 EB05 47.1 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Philadelphia chromosome positive | 30 | 88.4 61.3–127.3ROR 88.6 · χ² 2,398 / p <1e-300 | 80.5 EB05 59.1 · IC025 +4.5 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious n=30 · ♀ 78% (drug 47%) · 100% clinician | no trial data cached |
| Vascular device occlusion | 14 | 87.8 51.4–149.9ROR 87.9 · χ² 1,069 / p 1e-234 | 75.8 EB05 48.0 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=14 | no trial data cached |
| Immune effector cell-associated neurotoxicity syndrome | 219 | 82.0 71.7–93.7ROR 83.7 · χ² 16,757 / p <1e-300 | 78.3 EB05 70.0 · IC025 +5.8 3/3 methods agree | Labeled — boxed warning exact term | serious n=219 · 96% clinician | no trial data cached |
| Human herpesvirus 6 encephalitis | 11 | 81.2 44.5–148.4ROR 81.3 · χ² 762 / p 4e-168 | 69.1 EB05 41.2 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Graft versus host disease in skin | 75 | 71.3 56.7–89.7ROR 71.8 · χ² 4,950 / p <1e-300 | 67.7 EB05 55.8 · IC025 +5.2 3/3 methods agree | Not in label — unassessed | serious n=74 · 93% clinician | no trial data cached |
| Neurotoxicity | 576 | 69.3 63.9–75.1ROR 73.3 · χ² 37,437 / p <1e-300 | 66.9 EB05 62.4 · IC025 +5.8 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 48.7 · 96% clinician | no trial data cached |
| Chloroma | 14 | 69.3 40.7–118.0ROR 69.4 · χ² 846 / p 3e-186 | 61.6 EB05 39.0 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious n=14 | no trial data cached |
| Graft versus host disease in liver | 22 | 64.4 42.1–98.4ROR 64.5 · χ² 1,270 / p 2e-278 | 59.4 EB05 41.3 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=22 · 100% clinician | no trial data cached |
| Fusarium infection | 21 | 64.0 41.5–98.8ROR 64.2 · χ² 1,202 / p 1e-263 | 58.9 EB05 40.6 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=21 · 100% clinician | no trial data cached |
| Trichosporon infection | 12 | 63.1 35.5–112.1ROR 63.2 · χ² 652 / p 4e-144 | 56.1 EB05 34.2 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Graft versus host disease in gastrointestinal tract | 62 | 60.6 47.1–78.0ROR 61.0 · χ² 3,471 / p <1e-300 | 57.9 EB05 46.8 · IC025 +4.9 3/3 methods agree | Not in label — unassessed | serious n=62 · 97% clinician | no trial data cached |
| Leukaemia recurrent | 49 | 60.3 45.4–80.1ROR 60.6 · χ² 2,717 / p <1e-300 | 57.3 EB05 45.1 · IC025 +4.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=49 · 94% clinician | no trial data cached |
| Metastases to spleen | 12 | 60.0 33.8–106.5ROR 60.0 · χ² 619 / p 5e-137 | 53.6 EB05 32.7 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
Trial cross-check not yet run for this drug (ClinicalTrials.gov pull covers the 800 most-reported drugs first).
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Pyrexia (fever) | 1,160 | 6.8 6.4–7.2ROR 7.5 · χ² 5,801 / p <1e-300 | 6.8 EB05 6.4 · IC025 +2.7 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 5.3 · 91% clinician | no trial data cached |
| Cytokine release syndrome | 1,095 | 123.3 116.3–130.6ROR 137.7 · χ² 125,082 / p <1e-300 | 115.9 EB05 110.3 · IC025 +6.7 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 84.5 · 96% clinician | no trial data cached |
| Acute lymphocytic leukaemia recurrent | 1,092 | 1,494.4 1,384.9–1,612.5ROR 1,670.1 · χ² 930,774 / p <1e-300 | 841.9 EB05 800.8 · IC025 +9.2 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=1,090 · 97% clinician | no trial data cached |
| Off label use (used outside approved label) | 723 | 1.7 1.6–1.8ROR 1.7 · χ² 209 / p 1e-47 | 1.7 EB05 1.6 · IC025 +0.6 | Reporting / coding artifact | serious PRR 1.6 | no trial data cached |
| Death | 658 | 1.5 1.4–1.7ROR 1.6 · χ² 131 / p 1e-30 | 1.5 EB05 1.4 · IC025 +0.5 | Outcome field, not a reaction boxed warning mentions mortality | serious PRR 1.1 | no trial data cached |
| Neurotoxicity | 576 | 69.3 63.9–75.1ROR 73.3 · χ² 37,437 / p <1e-300 | 66.9 EB05 62.4 · IC025 +5.8 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 48.7 · 96% clinician | no trial data cached |
| Drug ineffective (drug did not work) | 426 | 0.7 0.6–0.7ROR 0.6 · χ² 83 / p 4e-20 | 0.7 EB05 0.6 · IC025 -0.8 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | serious PRR 1.2 · 92% clinician | no trial data cached |
| Headache | 370 | 1.2 1.1–1.3ROR 1.2 · χ² 12 / p 3e-4 | 1.2 EB05 1.1 · IC025 +0.1 | Labeled — boxed warning exact term | serious PRR 1.5 | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 319 | 4.8 4.3–5.3ROR 4.9 · χ² 950 / p 6e-209 | 4.7 EB05 4.3 · IC025 +2.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.6 · 96% clinician | no trial data cached |
| Febrile neutropenia | 307 | 9.4 8.4–10.5ROR 9.7 · χ² 2,296 / p <1e-300 | 9.3 EB05 8.5 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 6.8 · 95% clinician | no trial data cached |
| Therapy non-responder | 279 | 12.7 11.3–14.3ROR 13.1 · χ² 2,990 / p <1e-300 | 12.6 EB05 11.4 · IC025 +3.4 3/3 methods agree | Reporting / coding artifact | serious PRR 13.0 · 97% clinician | no trial data cached |
| Tremor (shaking) | 276 | 3.4 3.0–3.8ROR 3.4 · χ² 458 / p 6e-102 | 3.3 EB05 3.0 · IC025 +1.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.3 · 92% clinician | no trial data cached |
| Seizure | 269 | 4.7 4.2–5.3ROR 4.8 · χ² 794 / p 5e-175 | 4.7 EB05 4.2 · IC025 +2.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.6 · 94% clinician | no trial data cached |
| Infection | 260 | 3.7 3.2–4.1ROR 3.7 · χ² 500 / p 4e-111 | 3.6 EB05 3.3 · IC025 +1.7 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 3.2 · 96% clinician | no trial data cached |
| Acute lymphocytic leukaemia | 247 | 193.2 169.8–219.9ROR 197.9 · χ² 42,888 / p <1e-300 | 173.9 EB05 156.4 · IC025 +6.8 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=244 · 93% clinician | no trial data cached |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- B-cell aplasia — n=31, PRR 281.0
- Graft versus host disease in skin — n=75, PRR 71.3
- Graft versus host disease in liver — n=22, PRR 64.4
- Fusarium infection — n=21, PRR 64.0
- Graft versus host disease in gastrointestinal tract — n=62, PRR 60.6
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Blinatumomab?
In FDA FAERS, the most frequently co-reported reaction terms for Blinatumomab are pyrexia, cytokine release syndrome, acute lymphocytic leukaemia recurrent, neurotoxicity, headache, neutropenia. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Blinatumomab have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: CYTOKINE RELEASE SYNDROME and NEUROLOGICAL TOXICITIES including IMMUNE EFFECTOR CELL-ASSOCIATED NEUROTOXICITY SYNDROME Cytokine Release Syndrome (CRS), which may be life-threatening or fatal, occurred in patients receiving BLINCYTO.
Do FAERS signals prove that Blinatumomab causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 38b482a8-960b-4591-9857-5031ecb830aa, effective 20260414; matched on
openfda.generic_name.exact:"BLINATUMOMAB") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 1,000 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath
Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.