Drug · FAERS side-effect profile with label screen
Pegaspargase side effects: what 12,172 FDA adverse event reports show
Drug class
Asparagine-specific Enzyme
FDA label (Established Pharmacologic Class)
Brand names
Oncaspar
openFDA label
Who reports
12,172 reports · 98% serious · 1,557 with death outcome · 42% female
openFDA FAERS counts, all years, deduplication not applied
Used for
ONCASPAR is an asparagine specific enzyme indicated as a component of a multi-agent chemotherapeutic regimen for treatment of pediatric and adult patients with: First-line acute lymphoblastic leukemia ( 1.1 ) Acute lymphoblastic leukemia and hypersensi.
FDA label, Indications and Usage
What it is
Pegaspargase is a conjugate of monomethoxypolyethylene glycol (mPEG) and L-asparaginase (L-asparagine amidohydrolase), an asparagine specific enzyme. L-asparaginase is a tetrameric enzyme that is produced endogenously by E. coli and consists of identical 34.5 kDa subunits.
FDA label, Description section
Boxed warning
None in the current 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 adverse reaction 2Labeled (related wording) 1Likely indication confounding 1Lab value / disease marker 5Not in label — unassessed 31
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- 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.
- 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. 967 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 |
|---|---|---|---|---|---|---|
| Antithrombin iii | 13 | 7,362.4 2,098.3–25,833.4ROR 7,370.3 · χ² 16,587 / p <1e-300 | 454.2 EB05 282.5 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=13 | no trial data cached |
| Human bocavirus infection | 132 | 4,004.8 2,931.3–5,471.6ROR 4,048.7 · χ² 156,199 / p <1e-300 | 1,016.2 EB05 878.8 · IC025 +7.5 3/3 methods agree | Not in label — unassessed | serious n=132 · ♀ 100% (drug 42%) | no trial data cached |
| Lymphoid tissue hypoplasia | 78 | 1,920.6 1,389.9–2,654.1ROR 1,933.0 · χ² 69,347 / p <1e-300 | 737.6 EB05 610.1 · IC025 +6.7 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=78 | no trial data cached |
| Thymus hypoplasia | 84 | 1,659.5 1,229.2–2,240.4ROR 1,671.0 · χ² 69,598 / p <1e-300 | 704.3 EB05 586.7 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious n=84 | no trial data cached |
| Perineal necrosis | 19 | 1,537.2 826.7–2,858.5ROR 1,539.6 · χ² 14,517 / p <1e-300 | 444.6 EB05 300.8 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=19 | no trial data cached |
| Cystitis bacterial | 106 | 783.0 622.5–984.9ROR 789.9 · χ² 56,138 / p <1e-300 | 488.8 EB05 415.5 · IC025 +6.9 3/3 methods agree | Not in label — unassessed | serious n=106 | no trial data cached |
| Hypofibrinogenaemia | 300 | 775.8 677.6–888.3ROR 795.4 · χ² 158,847 / p <1e-300 | 515.3 EB05 468.2 · IC025 +8.0 3/3 methods agree | Not in label — unassessed | serious n=299 · 97% clinician | no trial data cached |
| Norovirus test positive | 99 | 761.1 600.9–964.0ROR 767.3 · χ² 51,378 / p <1e-300 | 477.2 EB05 403.4 · IC025 +6.8 3/3 methods agree | Lab value / disease marker | serious n=99 | no trial data cached |
| Mycobacterium chelonae infection | 177 | 546.8 462.0–647.1ROR 554.8 · χ² 72,539 / p <1e-300 | 396.1 EB05 349.5 · IC025 +7.3 3/3 methods agree | Not in label — unassessed | serious n=177 | no trial data cached |
| Antithrombin iii decreased | 56 | 457.4 340.7–614.1ROR 459.5 · χ² 19,736 / p <1e-300 | 321.0 EB05 256.5 · IC025 +6.0 3/3 methods agree | Not in label — unassessed | serious n=56 · 100% clinician | no trial data cached |
| Abscess bacterial | 70 | 420.3 323.7–545.6ROR 422.7 · χ² 23,137 / p <1e-300 | 308.7 EB05 252.6 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=70 | no trial data cached |
| Secondary immunodeficiency | 229 | 409.6 354.9–472.6ROR 417.4 · χ² 74,878 / p <1e-300 | 321.3 EB05 287.9 · IC025 +7.4 3/3 methods agree | Labeled (related wording) related wording | serious n=229 · ♀ 100% (drug 42%) | no trial data cached |
| Fibrinous bronchitis | 14 | 403.2 225.2–721.8ROR 403.6 · χ² 4,220 / p <1e-300 | 225.9 EB05 143.0 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=14 | no trial data cached |
| Antithrombin iii deficiency | 15 | 354.0 203.0–617.2ROR 354.4 · χ² 4,082 / p <1e-300 | 213.7 EB05 137.5 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=15 | no trial data cached |
| Febrile bone marrow aplasia | 677 | 332.9 307.2–360.8ROR 352.5 · χ² 187,088 / p <1e-300 | 276.4 EB05 259.3 · IC025 +7.7 3/3 methods agree | Not in label — unassessed | serious n=677 · 100% clinician | no trial data cached |
| Corona virus infection | 64 | 297.1 227.9–387.2ROR 298.7 · χ² 15,825 / p <1e-300 | 235.3 EB05 190.8 · IC025 +6.0 3/3 methods agree | Not in label — unassessed | serious n=64 | no trial data cached |
| Periorbital infection | 11 | 263.2 139.5–496.6ROR 263.5 · χ² 2,266 / p <1e-300 | 163.8 EB05 97.6 · IC025 +3.4 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Bacillus test positive | 13 | 256.8 143.4–460.1ROR 257.1 · χ² 2,660 / p <1e-300 | 168.5 EB05 104.8 · IC025 +3.7 3/3 methods agree | Lab value / disease marker | serious n=13 | no trial data cached |
| Pseudomonal sepsis | 214 | 238.4 206.9–274.8ROR 242.7 · χ² 44,164 / p <1e-300 | 205.4 EB05 183.3 · IC025 +6.9 3/3 methods agree | Not in label — unassessed | serious n=214 · ♀ 71% (drug 42%) | no trial data cached |
| Chemotherapeutic drug level increased | 17 | 188.8 114.4–311.5ROR 189.0 · χ² 2,691 / p <1e-300 | 143.0 EB05 94.6 · IC025 +4.1 3/3 methods agree | Lab value / disease marker | serious n=17 | no trial data cached |
| Perineal infection | 19 | 180.3 112.4–289.3ROR 180.6 · χ² 2,903 / p <1e-300 | 140.4 EB05 95.0 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=19 | no trial data cached |
| Bacillus bacteraemia | 10 | 171.6 89.6–328.8ROR 171.8 · χ² 1,389 / p <1e-300 | 120.7 EB05 70.1 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious n=10 | no trial data cached |
| Parainfluenzae virus infection | 139 | 170.0 142.9–202.2ROR 172.0 · χ² 21,080 / p <1e-300 | 151.5 EB05 131.5 · IC025 +6.4 3/3 methods agree | Not in label — unassessed | serious n=139 | no trial data cached |
| Stomatococcal infection | 11 | 169.9 91.4–315.7ROR 170.1 · χ² 1,529 / p <1e-300 | 122.3 EB05 72.9 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Disseminated aspergillosis | 40 | 160.7 116.2–222.1ROR 161.2 · χ² 5,654 / p <1e-300 | 137.4 EB05 105.2 · IC025 +5.2 3/3 methods agree | Not in label — unassessed | serious n=40 | no trial data cached |
| Enterobacter infection | 143 | 160.5 135.3–190.3ROR 162.4 · χ² 20,563 / p <1e-300 | 143.9 EB05 125.2 · IC025 +6.3 3/3 methods agree | Not in label — unassessed | serious n=143 · ♀ 89% (drug 42%) | no trial data cached |
| Blood fibrinogen decreased | 84 | 139.6 111.9–174.3ROR 140.6 · χ² 10,557 / p <1e-300 | 125.5 EB05 104.5 · IC025 +5.8 3/3 methods agree | Labeled adverse reaction exact term | serious n=82 · 95% clinician | no trial data cached |
| Human herpesvirus 6 infection | 142 | 138.7 117.0–164.5ROR 140.4 · χ² 17,826 / p <1e-300 | 126.2 EB05 109.7 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=142 · ♀ 92% (drug 42%) | no trial data cached |
| Superior sagittal sinus thrombosis | 58 | 133.2 102.0–173.9ROR 133.8 · χ² 6,933 / p <1e-300 | 118.8 EB05 95.3 · IC025 +5.5 3/3 methods agree | Labeled adverse reaction exact term | serious n=58 · 98% clinician | no trial data cached |
| Gallbladder oedema | 21 | 132.6 85.1–206.7ROR 132.9 · χ² 2,424 / p <1e-300 | 110.9 EB05 76.6 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=21 · 95% clinician | no trial data cached |
| Hypertriglyceridaemia | 410 | 130.3 118.0–143.8ROR 134.8 · χ² 48,736 / p <1e-300 | 120.4 EB05 110.9 · IC025 +6.6 3/3 methods agree | Not in label — unassessed | serious n=403 · 96% clinician | no trial data cached |
| Abscess fungal | 11 | 123.8 67.1–228.2ROR 123.9 · χ² 1,137 / p 2e-249 | 96.6 EB05 57.6 · IC025 +3.2 3/3 methods agree | Not in label — unassessed | serious n=11 | no trial data cached |
| Escherichia pyelonephritis | 16 | 117.2 70.6–194.4ROR 117.3 · χ² 1,617 / p <1e-300 | 97.3 EB05 63.5 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=16 | no trial data cached |
| Diffuse alveolar damage | 72 | 114.6 90.4–145.5ROR 115.3 · χ² 7,493 / p <1e-300 | 104.5 EB05 85.8 · IC025 +5.6 3/3 methods agree | Not in label — unassessed | serious n=72 | no trial data cached |
| Pyomyositis | 18 | 111.2 69.1–179.1ROR 111.4 · χ² 1,743 / p <1e-300 | 94.3 EB05 63.1 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=18 | no trial data cached |
| Enterovirus test positive | 10 | 104.9 55.4–198.6ROR 105.0 · χ² 874 / p 3e-192 | 83.6 EB05 48.5 · IC025 +3.0 3/3 methods agree | Lab value / disease marker | serious n=10 | no trial data cached |
| Viraemia | 79 | 103.6 82.6–130.0ROR 104.3 · χ² 7,473 / p <1e-300 | 95.5 EB05 79.1 · IC025 +5.6 3/3 methods agree | Not in label — unassessed | serious n=79 | no trial data cached |
| Enterococcus test positive | 35 | 97.6 69.5–137.2ROR 97.9 · χ² 3,075 / p <1e-300 | 88.1 EB05 66.2 · IC025 +4.8 3/3 methods agree | Lab value / disease marker | serious n=34 · 100% clinician | no trial data cached |
| Pneumatosis intestinalis | 142 | 90.7 76.7–107.3ROR 91.8 · χ² 11,875 / p <1e-300 | 85.2 EB05 74.1 · IC025 +5.8 3/3 methods agree | Not in label — unassessed | serious n=141 · ♀ 86% (drug 42%) | no trial data cached |
| Rhinovirus infection | 185 | 88.2 76.1–102.1ROR 89.5 · χ² 15,077 / p <1e-300 | 83.2 EB05 73.6 · IC025 +5.9 3/3 methods agree | Not in label — unassessed | serious n=185 · ♀ 75% (drug 42%) | 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 |
|---|---|---|---|---|---|---|
| Febrile neutropenia | 1,584 | 42.2 40.3–44.2ROR 48.4 · χ² 62,333 / p <1e-300 | 41.2 EB05 39.5 · IC025 +5.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 24.2 · 96% clinician | no trial data cached |
| Pyrexia (fever) | 777 | 3.9 3.6–4.1ROR 4.1 · χ² 1,677 / p <1e-300 | 3.9 EB05 3.6 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 2.8 · 95% clinician | no trial data cached |
| Febrile bone marrow aplasia | 677 | 332.9 307.2–360.8ROR 352.5 · χ² 187,088 / p <1e-300 | 276.4 EB05 259.3 · IC025 +7.7 3/3 methods agree | Not in label — unassessed | serious n=677 · 100% clinician | no trial data cached |
| Vomiting | 603 | 2.2 2.1–2.4ROR 2.3 · χ² 410 / p 1e-91 | 2.2 EB05 2.1 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 1.9 · 97% clinician | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 572 | 7.3 6.7–7.9ROR 7.6 · χ² 3,110 / p <1e-300 | 7.2 EB05 6.8 · IC025 +2.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.4 · 98% clinician | no trial data cached |
| Sepsis (blood infection) | 562 | 8.7 8.0–9.4ROR 9.1 · χ² 3,831 / p <1e-300 | 8.6 EB05 8.1 · IC025 +3.0 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 5.1 · 97% clinician | no trial data cached |
| Abdominal pain | 512 | 3.8 3.5–4.1ROR 3.9 · χ² 1,063 / p 2e-233 | 3.8 EB05 3.5 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.9 · 97% clinician | no trial data cached |
| Hypotension (low blood pressure) | 464 | 4.0 3.7–4.4ROR 4.1 · χ² 1,048 / p 4e-230 | 4.0 EB05 3.7 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 2.7 · 97% clinician | no trial data cached |
| Pancreatitis (pancreas inflammation) | 412 | 13.5 12.3–14.9ROR 13.9 · χ² 4,735 / p <1e-300 | 13.4 EB05 12.3 · IC025 +3.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.9 · 96% clinician | no trial data cached |
| Hypertriglyceridaemia | 410 | 130.3 118.0–143.8ROR 134.8 · χ² 48,736 / p <1e-300 | 120.4 EB05 110.9 · IC025 +6.6 3/3 methods agree | Not in label — unassessed | serious n=403 · 96% clinician | no trial data cached |
| Thrombocytopenia (low platelets) | 406 | 6.3 5.7–6.9ROR 6.5 · χ² 1,805 / p <1e-300 | 6.2 EB05 5.7 · IC025 +2.5 3/3 methods agree | Not in label — unassessed | serious PRR 3.8 · 98% clinician | no trial data cached |
| Nausea | 404 | 0.9 0.8–1.0ROR 0.9 · χ² 6 / p 0.005 | 0.9 EB05 0.8 · IC025 -0.3 PRR-only: not supported by EBGM or IC | Not in label — unassessed | serious PRR 1.0 · 98% clinician | no trial data cached |
| Hyperbilirubinaemia | 372 | 64.5 58.3–71.4ROR 66.5 · χ² 22,362 / p <1e-300 | 62.0 EB05 56.9 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious PRR 36.8 · 99% clinician | no trial data cached |
| Pneumonia (lung infection) | 362 | 1.9 1.7–2.1ROR 2.0 · χ² 164 / p 9e-38 | 1.9 EB05 1.8 · IC025 +0.8 | Labeled adverse reaction exact term | serious PRR 1.2 · 92% clinician | no trial data cached |
| Bacterial infection | 345 | 32.6 29.3–36.2ROR 33.5 · χ² 10,345 / p <1e-300 | 31.9 EB05 29.2 · IC025 +4.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 21.5 · ♀ 72% (drug 42%) | 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.
- Human bocavirus infection — n=132, PRR 4,004.8
- Thymus hypoplasia — n=84, PRR 1,659.5
- Cystitis bacterial — n=106, PRR 783.0
- Hypofibrinogenaemia — n=300, PRR 775.8
- Mycobacterium chelonae infection — n=177, PRR 546.8
- Antithrombin iii decreased — n=56, PRR 457.4
- Abscess bacterial — n=70, PRR 420.3
- Febrile bone marrow aplasia — n=677, PRR 332.9
- Corona virus infection — n=64, PRR 297.1
- Pseudomonal sepsis — n=214, PRR 238.4
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 Pegaspargase?
In FDA FAERS, the most frequently co-reported reaction terms for Pegaspargase are febrile neutropenia, pyrexia, febrile bone marrow aplasia, vomiting, neutropenia, sepsis. 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 Pegaspargase have an FDA boxed warning?
No. The FDA label retrieved for Pegaspargase has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Pegaspargase 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 ac7b6a6f-6ddb-48c6-8088-d8a8e3fea6ce, effective 20241007; matched on
openfda.generic_name.exact:"PEGASPARGASE") - 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, 1,007 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.