Ecallantide side effects: what 1,861 FDA adverse event reports show
Drug class
Plasma Kallikrein Inhibitor
Brand names
Kalbitor
Who reports
1,861 reports · 61% serious · 34 with death outcome · 85% female
Used for
KALBITOR ® (ecallantide) is indicated for treatment of acute attacks of hereditary angioedema (HAE) in patients 12 years of age and older. KALBITOR is a plasma kallikrein inhibitor indicated for treatment of acute attacks of hereditary angioedema (HAE) in patients 12 years of age and older. ( 1 )
What it is
KALBITOR (ecallantide) is a human plasma kallikrein inhibitor for injection for subcutaneous use. Ecallantide is a 60-amino-acid protein produced in Pichia pastoris yeast cells by recombinant DNA technology. KALBITOR is a clear and colorless, sterile, and nonpyrogenic solution.
Boxed warning
ANAPHYLAXIS Anaphylaxis has been reported after administration of KALBITOR. Because of the risk of anaphylaxis, KALBITOR should only be administered by a healthcare professional with appropriate medical support to manage anaphylaxis and hereditary angioedema.
Causality screen of the 27 strongest signals
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 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.
- 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.
- 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. 25 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Hereditary angioedema | 779 | 903.6 853.4–956.8ROR 1,553.4 · χ² 649,047 / p <1e-300 | 818.8 EB05 771.7 · IC025 +9.0 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 739.4 | no trial data cached |
| Pharyngeal swelling | 32 | 37.8 26.8–53.3ROR 38.4 · χ² 1,106 / p 7e-243 | 36.9 EB05 27.4 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=9 | no trial data cached |
| Prescribed overdose | 42 | 24.5 18.2–33.1ROR 25.0 · χ² 922 / p 7e-203 | 24.2 EB05 18.7 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 32.9 | no trial data cached |
| Pharyngeal oedema | 31 | 22.4 15.8–31.8ROR 22.8 · χ² 613 / p 1e-135 | 22.1 EB05 16.3 · IC025 +3.5 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 23.4 | no trial data cached |
| Insurance issue | 27 | 20.5 14.1–29.8ROR 20.8 · χ² 481 / p 6e-107 | 20.2 EB05 14.5 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 31.1 · 74% consumer | no trial data cached |
| Device related infection | 23 | 16.8 11.2–25.3ROR 17.0 · χ² 326 / p 3e-73 | 16.4 EB05 11.3 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 16.3 | no trial data cached |
| Poor venous access | 13 | 14.2 8.3–24.4ROR 14.3 · χ² 147 / p 5e-34 | 13.0 EB05 7.2 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious n=8 | no trial data cached |
| Anaphylactic reaction (severe allergic reaction) | 62 | 12.7 10.0–16.3ROR 13.1 · χ² 659 / p 1e-145 | 12.5 EB05 10.0 · IC025 +3.1 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 12.3 | no trial data cached |
| Pregnancy | 19 | 10.6 6.8–16.6ROR 10.7 · χ² 156 / p 5e-36 | 9.5 EB05 6.1 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 9.3 | no trial data cached |
| Drug administration error | 28 | 10.1 7.0–14.7ROR 10.3 · χ² 222 / p 2e-50 | 9.4 EB05 6.6 · IC025 +2.5 3/3 methods agree | Reporting / coding artifact | serious PRR 12.1 · 71% consumer | no trial data cached |
| Therapeutic response decreased | 54 | 10.1 7.8–13.1ROR 10.4 · χ² 434 / p 9e-97 | 9.7 EB05 7.6 · IC025 +2.8 3/3 methods agree | Reporting / coding artifact | serious PRR 19.0 | no trial data cached |
| Adverse reaction | 10 | 8.5 4.6–15.8ROR 8.5 · χ² 59 / p 8e-15 | 6.6 EB05 3.7 · IC025 +1.6 3/3 methods agree | Reporting / coding artifact | serious n=6 | no trial data cached |
| Stress | 47 | 7.4 5.6–9.8ROR 7.5 · χ² 253 / p 3e-57 | 7.0 EB05 5.4 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 7.4 · 81% consumer | no trial data cached |
| Swollen tongue | 20 | 7.2 4.7–11.2ROR 7.3 · χ² 101 / p 5e-24 | 6.3 EB05 4.3 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 9.1 | no trial data cached |
| Inappropriate schedule of drug administration | 45 | 7.0 5.3–9.4ROR 7.2 · χ² 227 / p 1e-51 | 6.6 EB05 5.1 · IC025 +2.2 3/3 methods agree | Reporting / coding artifact | serious PRR 20.6 | no trial data cached |
| Kidney infection | 12 | 6.9 3.9–12.1ROR 6.9 · χ² 55 / p 7e-14 | 5.6 EB05 3.4 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 7.3 | no trial data cached |
| Foot fracture | 10 | 5.9 3.2–11.0ROR 6.0 · χ² 36 / p 9e-10 | 4.8 EB05 2.8 · IC025 +1.2 3/3 methods agree | Not in label — unassessed | serious PRR 4.0 | no trial data cached |
| Road traffic accident | 20 | 5.4 3.5–8.3ROR 5.4 · χ² 67 / p 1e-16 | 4.8 EB05 3.3 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 3.0 | no trial data cached |
| Product availability issue | 10 | 5.0 2.7–9.3ROR 5.0 · χ² 28 / p 5e-8 | 4.2 EB05 2.4 · IC025 +1.0 3/3 methods agree | Reporting / coding artifact | serious PRR 9.9 | no trial data cached |
| Drug ineffective for unapproved indication | 24 | 4.9 3.3–7.2ROR 4.9 · χ² 70 / p 3e-17 | 4.5 EB05 3.2 · IC025 +1.5 3/3 methods agree | Reporting / coding artifact | serious PRR 7.3 | no trial data cached |
| Throat tightness | 11 | 4.6 2.5–8.3ROR 4.6 · χ² 27 / p 8e-8 | 3.9 EB05 2.4 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 3.4 | no trial data cached |
| Extra dose administered | 16 | 4.5 2.8–7.4ROR 4.6 · χ² 40 / p 1e-10 | 4.0 EB05 2.7 · IC025 +1.2 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial data cached |
| Injection site rash | 10 | 3.7 2.0–6.9ROR 3.7 · χ² 17 / p 2e-5 | 3.3 EB05 1.9 · IC025 +0.6 | Labeled (related wording) related wording | – | no trial data cached |
| Abortion spontaneous | 10 | 2.8 1.5–5.2ROR 2.8 · χ² 10 / p 8e-4 | 2.6 EB05 1.5 · IC025 +0.3 | Not in label — unassessed | serious PRR 2.7 | no trial data cached |
| Injection site reaction | 15 | 2.5 1.5–4.1ROR 2.5 · χ² 12 / p 3e-4 | 2.4 EB05 1.5 · IC025 +0.4 | Labeled adverse reaction exact term | serious PRR 5.6 | no trial data cached |
| Injection site erythema (redness where injected) | 25 | 2.3 1.5–3.4ROR 2.3 · χ² 17 / p 2e-5 | 2.2 EB05 1.6 · IC025 +0.5 | Labeled (related wording) related wording | serious PRR 6.3 | no trial data cached |
| Injection site swelling | 15 | 2.2 1.3–3.7ROR 2.2 · χ² 9 / p 0.001 | 2.1 EB05 1.4 · IC025 +0.2 | Labeled (related wording) related wording | serious PRR 6.4 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
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 |
|---|---|---|---|---|---|---|
| Hereditary angioedema | 779 | 903.6 853.4–956.8ROR 1,553.4 · χ² 649,047 / p <1e-300 | 818.8 EB05 771.7 · IC025 +9.0 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 739.4 | no trial data cached |
| Anaphylactic reaction (severe allergic reaction) | 62 | 12.7 10.0–16.3ROR 13.1 · χ² 659 / p 1e-145 | 12.5 EB05 10.0 · IC025 +3.1 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 12.3 | no trial data cached |
| Therapeutic response decreased | 54 | 10.1 7.8–13.1ROR 10.4 · χ² 434 / p 9e-97 | 9.7 EB05 7.6 · IC025 +2.8 3/3 methods agree | Reporting / coding artifact | serious PRR 19.0 | no trial data cached |
| Stress | 47 | 7.4 5.6–9.8ROR 7.5 · χ² 253 / p 3e-57 | 7.0 EB05 5.4 · IC025 +2.3 3/3 methods agree | Not in label — unassessed | serious PRR 7.4 · 81% consumer | no trial data cached |
| Inappropriate schedule of drug administration | 45 | 7.0 5.3–9.4ROR 7.2 · χ² 227 / p 1e-51 | 6.6 EB05 5.1 · IC025 +2.2 3/3 methods agree | Reporting / coding artifact | serious PRR 20.6 | no trial data cached |
| Prescribed overdose | 42 | 24.5 18.2–33.1ROR 25.0 · χ² 922 / p 7e-203 | 24.2 EB05 18.7 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 32.9 | no trial data cached |
| Injection site pain (pain where injected) | 37 | 1.4 1.0–1.9ROR 1.4 · χ² 3 / p 0.032 | 1.4 EB05 1.0 · IC025 -0.1 PRR-only: not supported by EBGM or IC | Labeled (related wording) related wording | serious PRR 4.3 | no trial data cached |
| Pharyngeal swelling | 32 | 37.8 26.8–53.3ROR 38.4 · χ² 1,106 / p 7e-243 | 36.9 EB05 27.4 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious n=9 | no trial data cached |
| Pharyngeal oedema | 31 | 22.4 15.8–31.8ROR 22.8 · χ² 613 / p 1e-135 | 22.1 EB05 16.3 · IC025 +3.5 3/3 methods agree | Labeled — boxed warning exact term | serious PRR 23.4 | no trial data cached |
| Drug administration error | 28 | 10.1 7.0–14.7ROR 10.3 · χ² 222 / p 2e-50 | 9.4 EB05 6.6 · IC025 +2.5 3/3 methods agree | Reporting / coding artifact | serious PRR 12.1 · 71% consumer | no trial data cached |
| Insurance issue | 27 | 20.5 14.1–29.8ROR 20.8 · χ² 481 / p 6e-107 | 20.2 EB05 14.5 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 31.1 · 74% consumer | no trial data cached |
| Injection site erythema (redness where injected) | 25 | 2.3 1.5–3.4ROR 2.3 · χ² 17 / p 2e-5 | 2.2 EB05 1.6 · IC025 +0.5 | Labeled (related wording) related wording | serious PRR 6.3 | no trial data cached |
| Drug ineffective for unapproved indication | 24 | 4.9 3.3–7.2ROR 4.9 · χ² 70 / p 3e-17 | 4.5 EB05 3.2 · IC025 +1.5 3/3 methods agree | Reporting / coding artifact | serious PRR 7.3 | no trial data cached |
| Device related infection | 23 | 16.8 11.2–25.3ROR 17.0 · χ² 326 / p 3e-73 | 16.4 EB05 11.3 · IC025 +3.0 3/3 methods agree | Reporting / coding artifact | serious PRR 16.3 | no trial data cached |
| Road traffic accident | 20 | 5.4 3.5–8.3ROR 5.4 · χ² 67 / p 1e-16 | 4.8 EB05 3.3 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 3.0 | 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.
- Pharyngeal swelling — n=32, PRR 37.8
- Prescribed overdose — n=42, PRR 24.5
- Insurance issue — n=27, PRR 20.5
- Stress — n=47, PRR 7.4
- Swollen tongue — n=20, PRR 7.2
- Road traffic accident — n=20, PRR 5.4
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 Ecallantide?
In FDA FAERS, the most frequently co-reported reaction terms for Ecallantide are hereditary angioedema, anaphylactic reaction, stress, prescribed overdose, injection site pain, pharyngeal swelling. 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 Ecallantide have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: ANAPHYLAXIS Anaphylaxis has been reported after administration of KALBITOR. Because of the risk of anaphylaxis, KALBITOR should only be administered by a healthcare professional with appropriate medical support to manage anaphylaxis and hereditary angioedema.
Do FAERS signals prove that Ecallantide 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 f56aec67-c662-477c-b866-bfc23e8809cf, effective 20250701; matched on
openfda.generic_name.exact:"ECALLANTIDE") - 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, 52 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.