Eculizumab side effects: what 54,001 FDA adverse event reports show

Eculizumab · Soliris · 1,203 reaction terms · 160,043 drug–reaction co-reports · data 2026-09-14

Drug class

Complement Inhibitor

FDA label (Established Pharmacologic Class) · compare the class

Brand names

Soliris

openFDA label

Who reports

54,001 reports · 60% serious · 5,611 with death outcome · 60% female

openFDA FAERS counts, all years, deduplication not applied

Used for

SOLIRIS is a complement inhibitor indicated for: the treatment of patients with paroxysmal nocturnal hemoglobinuria (PNH) to reduce hemolysis. ( 1.1 ) the treatment of patients with atypical hemolytic uremic syndrome (aHUS) to inhibit complement-mediated thrombotic microangiopathy. ( 1.2 ) Limitation of Use SOLIRIS is not indicated for the treatment of patients with Shiga toxin E.

FDA label, Indications and Usage

What it is

Eculizumab, a complement inhibitor, is a recombinant humanized monoclonal IgG2/4 κ antibody produced by murine myeloma cell culture and purified by standard bioprocess technology. Eculizumab c.

FDA label, Description section

Boxed warning

SERIOUS MENINGOCOCCAL INFECTIONS SOLIRIS, a complement inhibitor, increases the risk of serious infections caused by Neisseria meningitidis [see Warnings and Precautions (5.1) ] . Life-threatening and fatal meningococcal infections have occurred in patients treated with complement inhibitors.

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 1Labeled adverse reaction 3Labeled (related wording) 2Likely indication confounding 7Lab value / disease marker 15Not in label — unassessed 12

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.
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, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,163 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.

Show: hide coding/lab/outcome terms hide indication terms unlabeled only hide PRR-only

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Total complement activity decreased	49	1,872.1 948.4–3,695.5ROR 1,873.8 · calibrated p 4e-17 ✓	283.0 EB05 222.5 · IC025 +5.8 3/3 methods agree vs other Complement Inhibitors: PRR 11.0 (5.0–24.3)	Lab value / disease marker	serious n=43	not reported in cached trials
Total complement activity increased	38	1,037.0 561.9–1,913.7ROR 1,037.7 · calibrated p 5e-15 ✓	245.4 EB05 186.7 · IC025 +5.4 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	serious n=26 · 82% consumer	not reported in cached trials
Haemoglobinuria	719	706.2 624.4–798.7ROR 715.7 · calibrated p 1e-15 ✓	246.9 EB05 232.2 · IC025 +7.6 3/3 methods agree vs other Complement Inhibitors: PRR 70.7 (43.1–115.9)	Likely indication confounding term in indications	serious n=435 · 80% consumer	NCT02946463: 1/121 (0.8%) on Eculizumab (serious AE)
Haptoglobin abnormal	48	416.8 276.9–627.4ROR 417.2 · calibrated p 3e-12 ✓	185.2 EB05 145.3 · IC025 +5.6 3/3 methods agree vs other Complement Inhibitors: PRR 15.1 (6.0–37.9)	Not in label — unassessed	serious n=33 · 85% consumer	not reported in cached trials
Extravascular haemolysis	215	412.8 340.5–500.5ROR 414.4 · calibrated p 6e-13 ✓	195.5 EB05 174.5 · IC025 +6.9 3/3 methods agree vs other Complement Inhibitors: PRR 2.4 (2.0–3.0)	Likely indication confounding shares a disease stem with the indications wording	serious n=198	not reported in cached trials
Complement factor abnormal	51	360.8 246.1–529.0ROR 361.2 · calibrated p 8e-12 ✓	174.0 EB05 137.5 · IC025 +5.6 3/3 methods agree vs other Complement Inhibitors: PRR 20.0 (7.2–55.5)	Lab value / disease marker	serious n=37 · 82% consumer	not reported in cached trials
Meningococcal bacteraemia	45	350.9 234.1–525.8ROR 351.2 · calibrated p 1e-11 ✓	170.2 EB05 132.4 · IC025 +5.4 3/3 methods agree vs other Complement Inhibitors: PRR 14.2 (5.6–35.6)	Not in label — unassessed	serious n=45	not reported in cached trials
Meningococcal sepsis	86	322.1 241.8–429.1ROR 322.6 · calibrated p 1e-11 ✓	168.7 EB05 140.9 · IC025 +6.1 3/3 methods agree vs other Complement Inhibitors: PRR 6.8 (4.2–11.0)	Labeled adverse reaction exact term	serious n=86	NCT02946463: 1/124 (0.8%) on Eculizumab (serious AE)
Breakthrough haemolysis	140	226.6 183.9–279.3ROR 227.2 · calibrated p 2e-10 ✓	139.9 EB05 121.5 · IC025 +6.3 3/3 methods agree vs other Complement Inhibitors: PRR 1.3 (1.1–1.7)	Likely indication confounding shares a disease stem with the indications wording	serious n=140	NCT02946463: 1/119 (0.8%) on Eculizumab (serious AE)
Paroxysmal nocturnal haemoglobinuria	163	214.0 176.7–259.2ROR 214.6 · calibrated p 3e-10 ✓	135.4 EB05 118.8 · IC025 +6.3 3/3 methods agree vs other Complement Inhibitors: PRR 5.8 (4.2–8.1)	Likely indication confounding term in indications	serious n=155	NCT02946463: 1/121 (0.8%) on Eculizumab (serious AE)
Complement factor increased	28	198.1 125.5–312.7ROR 198.2 · calibrated p 3e-9 ✓	120.3 EB05 87.3 · IC025 +4.7 3/3 methods agree vs other Complement Inhibitors: PRR 11.0 (3.9–31.4)	Lab value / disease marker	serious n=18	not reported in cached trials
Meningitis meningococcal	56	196.3 142.2–270.9ROR 196.5 · calibrated p 1e-9 ✓	124.6 EB05 99.5 · IC025 +5.5 3/3 methods agree vs other Complement Inhibitors: PRR 5.2 (3.0–8.9)	Labeled (related wording) related wording	serious n=56	not reported in cached trials
Reticulocyte percentage increased	20	166.1 98.3–280.8ROR 166.2 · calibrated p 2e-8 ✓	104.7 EB05 71.6 · IC025 +4.2 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	–	not reported in cached trials
Haptoglobin decreased	235	161.8 138.9–188.4ROR 162.5 · calibrated p 3e-9 ✓	112.9 EB05 101.3 · IC025 +6.3 3/3 methods agree vs other Complement Inhibitors: PRR 10.6 (7.4–15.1)	Not in label — unassessed	serious n=202 · 73% consumer	not reported in cached trials
Reticulocyte count increased	231	154.8 132.9–180.4ROR 155.5 · calibrated p 4e-9 ✓	109.5 EB05 98.1 · IC025 +6.3 3/3 methods agree vs other Complement Inhibitors: PRR 8.4 (6.1–11.7)	Lab value / disease marker	serious n=167 · 71% consumer	not reported in cached trials
Meningococcal infection	87	147.7 115.4–189.2ROR 148.0 · calibrated p 8e-9 ✓	104.4 EB05 87.3 · IC025 +5.7 3/3 methods agree vs other Complement Inhibitors: PRR 3.6 (2.5–5.3)	Labeled — boxed warning exact term	serious n=62	not reported in cached trials
Reticulocyte count abnormal	31	146.2 96.7–221.2ROR 146.3 · calibrated p 2e-8 ✓	99.7 EB05 73.6 · IC025 +4.7 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	serious n=16 · 70% consumer	not reported in cached trials
Biopsy bone marrow	126	143.7 117.1–176.3ROR 144.0 · calibrated p 9e-9 ✓	103.1 EB05 88.9 · IC025 +5.9 3/3 methods agree vs other Complement Inhibitors: PRR 39.6 (16.2–96.8)	Not in label — unassessed	serious n=118 · 87% consumer	not reported in cached trials
Blood lactate dehydrogenase abnormal	176	137.8 116.0–163.7ROR 138.2 · calibrated p 1e-8 ✓	100.5 EB05 88.6 · IC025 +6.1 3/3 methods agree vs other Complement Inhibitors: PRR 21.3 (12.1–37.4)	Lab value / disease marker	serious n=123 · 80% consumer	not reported in cached trials
Plasmapheresis	133	134.8 110.6–164.2ROR 135.1 · calibrated p 1e-8 ✓	98.5 EB05 85.2 · IC025 +5.9 3/3 methods agree vs other Complement Inhibitors: only this drug	Labeled adverse reaction exact term	serious n=114 · 75% consumer	not reported in cached trials
Haemolysis	1,867	123.6 117.4–130.2ROR 128.0 · calibrated p 2e-8 ✓	93.6 EB05 90.0 · IC025 +6.4 3/3 methods agree vs other Complement Inhibitors: PRR 9.0 (8.0–10.2)	Likely indication confounding term in indications; also in warnings	serious PRR 80.9 · 71% consumer	NCT02946463: 1/119 (0.8%) on Eculizumab (serious AE)
C3 glomerulopathy	48	121.4 87.8–168.0ROR 121.6 · calibrated p 5e-8 ✓	89.2 EB05 70.0 · IC025 +5.1 3/3 methods agree vs other Complement Inhibitors: PRR 18.9 (6.8–52.3)	Not in label — unassessed	serious n=47 · ♀ 33% (drug 60%)	not reported in cached trials
Blood product transfusion dependent	97	115.1 91.7–144.4ROR 115.3 · calibrated p 5e-8 ✓	87.2 EB05 73.6 · IC025 +5.6 3/3 methods agree vs other Complement Inhibitors: only this drug	Not in label — unassessed	serious n=71 · 75% consumer	not reported in cached trials
Atypical haemolytic uraemic syndrome	184	114.9 97.4–135.4ROR 115.3 · calibrated p 5e-8 ✓	87.8 EB05 77.6 · IC025 +5.9 3/3 methods agree vs other Complement Inhibitors: PRR 7.2 (5.1–10.2)	Likely indication confounding term in indications	serious n=184	not reported in cached trials
Haptoglobin increased	29	103.5 68.7–156.1ROR 103.6 · calibrated p 3e-7 ✓	77.7 EB05 56.7 · IC025 +4.5 3/3 methods agree vs other Complement Inhibitors: only this drug	Not in label — unassessed	serious n=20	not reported in cached trials
Blood product transfusion	20	101.9 62.2–166.8ROR 101.9 · calibrated p 5e-7 ✓	75.1 EB05 51.3 · IC025 +4.0 3/3 methods agree vs other Complement Inhibitors: only this drug	Not in label — unassessed	–	not reported in cached trials
Blood lactate dehydrogenase decreased	63	89.5 68.0–117.7ROR 89.6 · calibrated p 4e-7 ✓	71.2 EB05 57.6 · IC025 +5.1 3/3 methods agree vs other Complement Inhibitors: PRR 24.8 (9.0–68.0)	Lab value / disease marker	serious n=44 · 84% consumer	not reported in cached trials
Budd-chiari syndrome	48	89.5 65.3–122.5ROR 89.5 · calibrated p 5e-7 ✓	70.7 EB05 55.5 · IC025 +4.9 3/3 methods agree vs other Complement Inhibitors: PRR 18.9 (6.8–52.3)	Not in label — unassessed	serious n=47	not reported in cached trials
Arteriovenous fistula occlusion	32	86.1 58.7–126.3ROR 86.1 · calibrated p 8e-7 ✓	67.7 EB05 50.2 · IC025 +4.5 3/3 methods agree vs other Complement Inhibitors: only this drug	Not in label — unassessed	serious n=32 · ♀ 100% (drug 60%)	not reported in cached trials
Neisseria infection	21	75.7 47.4–120.9ROR 75.7 · calibrated p 3e-6 ✓	60.1 EB05 41.4 · IC025 +4.0 3/3 methods agree vs other Complement Inhibitors: PRR 3.0 (1.4–6.2)	Labeled (related wording) related wording	serious n=20	not reported in cached trials
Iron overload	174	74.5 63.4–87.7ROR 74.8 · calibrated p 1e-6 ✓	62.1 EB05 54.7 · IC025 +5.5 3/3 methods agree vs other Complement Inhibitors: PRR 27.4 (14.5–51.7)	Not in label — unassessed	serious n=128 · 75% consumer	not reported in cached trials
Intravascular haemolysis	80	65.0 51.3–82.4ROR 65.1 · calibrated p 3e-6 ✓	55.0 EB05 45.6 · IC025 +5.0 3/3 methods agree vs other Complement Inhibitors: PRR 5.2 (3.3–8.3)	Labeled adverse reaction exact term	serious n=77	not reported in cached trials
Myasthenia gravis crisis	203	64.0 55.2–74.2ROR 64.2 · calibrated p 3e-6 ✓	54.7 EB05 48.7 · IC025 +5.4 3/3 methods agree vs other Complement Inhibitors: PRR 2.4 (1.9–3.0)	Likely indication confounding shares a disease stem with the indications wording	serious n=203	not reported in cached trials
Complement factor c3 decreased	34	64.0 44.5–92.0ROR 64.0 · calibrated p 5e-6 ✓	53.4 EB05 40.0 · IC025 +4.4 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	serious n=30	not reported in cached trials
Complement factor decreased	24	62.0 40.3–95.4ROR 62.0 · calibrated p 9e-6 ✓	51.4 EB05 36.3 · IC025 +4.0 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	serious n=19	not reported in cached trials
Iron binding capacity total decreased	29	58.9 39.9–87.1ROR 59.0 · calibrated p 1e-5 ✓	49.6 EB05 36.2 · IC025 +4.2 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	serious n=27 · 72% consumer	not reported in cached trials
Packed red blood cell transfusion	166	54.8 46.6–64.4ROR 54.9 · calibrated p 8e-6 ✓	47.8 EB05 42.0 · IC025 +5.1 3/3 methods agree vs other Complement Inhibitors: PRR 65.3 (24.2–175.9)	Not in label — unassessed	serious n=143 · 87% consumer	not reported in cached trials
Red blood cell schistocytes present	39	53.2 38.1–74.4ROR 53.3 · calibrated p 2e-5 ✓	45.9 EB05 35.0 · IC025 +4.4 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	serious n=33	not reported in cached trials
Blood lactate dehydrogenase increased	1,586	42.8 40.7–45.1ROR 44.1 · calibrated p 3e-5 ✓	38.6 EB05 37.0 · IC025 +5.2 3/3 methods agree vs other Complement Inhibitors: PRR 14.0 (12.0–16.3)	Lab value / disease marker	serious PRR 27.4 · 76% consumer	not reported in cached trials
Coombs test positive	27	42.6 28.6–63.4ROR 42.6 · calibrated p 7e-5 ✓	37.5 EB05 27.1 · IC025 +3.9 3/3 methods agree vs other Complement Inhibitors: only this drug	Lab value / disease marker	serious n=19	not reported in cached trials

Trial evidence (ClinicalTrials.gov)

✓ Trial adverse-event data found on ClinicalTrials.gov

Largest completed trials with posted results that list Eculizumab as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (5 of 40 signal terms matched).

NCT02145182 — Prevention of Delayed Graft Function Using Eculizumab Therapy (PROTECT Study) (N=288, PHASE2, PHASE3; 301 AE terms posted; arms: Eculizumab; Placebo)
NCT02946463 — ALXN1210 (Ravulizumab) Versus Eculizumab in Complement Inhibitor Treatment-Naïve Adult Participants With Parox (N=272, PHASE3; 148 AE terms posted; arms: Ravulizumab: Primary Evaluation; Eculizumab: Primary Evaluation; Ravulizumab/Ravulizumab: Extension Perio; Eculizumab/Ravulizumab: Extension Period)

Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.

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
Fatigue (tiredness)	5,890	3.0 2.9–3.0ROR 3.2 · calibrated p 0.565	2.9 EB05 2.9 · IC025 +1.5 3/3 methods agree vs other Complement Inhibitors: PRR 5.2 (5.0–5.5)	Labeled adverse reaction exact term	serious PRR 2.6 · 84% consumer	NCT02946463: 10/119 (8.4%) on Eculizumab
Off label use (used outside approved label)	4,750	2.1 2.1–2.2ROR 2.2 · calibrated p 0.932	2.1 EB05 2.1 · IC025 +1.0 3/3 methods agree vs other Complement Inhibitors: PRR 13.3 (12.2–14.5)	Reporting / coding artifact	serious PRR 1.9	not reported in cached trials
Haemoglobin decreased	3,924	15.4 14.9–15.8ROR 16.5 · calibrated p 0.005 ✓	14.8 EB05 14.4 · IC025 +3.8 3/3 methods agree vs other Complement Inhibitors: PRR 11.6 (10.6–12.7)	Likely indication confounding term in indications	serious PRR 12.3 · 79% consumer	NCT02946463: 1/119 (0.8%) on Eculizumab (serious AE)
Headache	3,485	2.2 2.1–2.2ROR 2.2 · calibrated p 0.928	2.2 EB05 2.1 · IC025 +1.1 3/3 methods agree vs other Complement Inhibitors: PRR 7.2 (6.7–7.8)	Labeled adverse reaction exact term	serious PRR 1.9 · 80% consumer	NCT02145182: 1/146 (0.7%) control (serious AE)
Death	2,726	1.2 1.2–1.3ROR 1.2 · calibrated p 0.468	1.2 EB05 1.2 · IC025 +0.2 vs other Complement Inhibitors: PRR 7.3 (6.7–7.9)	Outcome field, not a reaction boxed warning mentions mortality	serious PRR 1.2	NCT02145182: 1/142 (0.7%) on Eculizumab (serious AE)
Pyrexia (fever)	2,423	2.7 2.6–2.8ROR 2.8 · calibrated p 0.691	2.7 EB05 2.6 · IC025 +1.4 3/3 methods agree vs other Complement Inhibitors: PRR 14.1 (12.4–15.9)	Labeled adverse reaction exact term	serious PRR 2.5 · 78% consumer	NCT02145182: 4/142 (2.8%) on Eculizumab; 4/146 (2.7%) control (serious AE)
Dyspnoea (shortness of breath)	2,190	1.5 1.4–1.6ROR 1.5 · calibrated p 0.659	1.5 EB05 1.5 · IC025 +0.5 vs other Complement Inhibitors: PRR 6.7 (6.1–7.3)	Labeled adverse reaction exact term	serious PRR 1.4 · 79% consumer	NCT02145182: 3/146 (2.1%) control (serious AE)
Asthenia (weakness)	2,035	2.1 2.0–2.2ROR 2.2 · calibrated p 0.977	2.1 EB05 2.0 · IC025 +1.0 3/3 methods agree vs other Complement Inhibitors: PRR 3.6 (3.3–3.9)	Likely indication confounding term in indications; also in warnings	serious PRR 1.8 · 83% consumer	NCT02145182: 2/142 (1.4%) on Eculizumab (serious AE)
Nausea	1,992	1.0 0.9–1.0ROR 1.0 · calibrated p 0.293	1.0 EB05 0.9 · IC025 -0.1 PRR-only: not supported by EBGM or IC vs other Complement Inhibitors: PRR 9.3 (8.3–10.4)	Labeled adverse reaction exact term	serious PRR 1.0 · 80% consumer	NCT02145182: 1/142 (0.7%) on Eculizumab (serious AE)
Drug ineffective (drug did not work)	1,936	0.6 0.5–0.6ROR 0.6 · calibrated p 0.067	0.6 EB05 0.5 · IC025 -0.9 PRR-only: not supported by EBGM or IC vs other Complement Inhibitors: PRR 4.1 (3.8–4.5)	Reporting / coding artifact	serious PRR 1.1	not reported in cached trials
Haemolysis	1,867	123.6 117.4–130.2ROR 128.0 · calibrated p 2e-8 ✓	93.6 EB05 90.0 · IC025 +6.4 3/3 methods agree vs other Complement Inhibitors: PRR 9.0 (8.0–10.2)	Likely indication confounding term in indications; also in warnings	serious PRR 80.9 · 71% consumer	NCT02946463: 1/119 (0.8%) on Eculizumab (serious AE)
Platelet count decreased	1,832	6.8 6.5–7.1ROR 7.0 · calibrated p 0.100	6.7 EB05 6.4 · IC025 +2.7 3/3 methods agree vs other Complement Inhibitors: PRR 14.1 (12.2–16.3)	Labeled (related wording) related wording	serious PRR 6.2 · 78% consumer	not reported in cached trials
Malaise (feeling unwell)	1,796	1.6 1.5–1.7ROR 1.6 · calibrated p 0.712	1.6 EB05 1.5 · IC025 +0.6 vs other Complement Inhibitors: PRR 6.0 (5.5–6.7)	Not in label — unassessed	serious PRR 1.6 · 86% consumer	not reported in cached trials
Blood lactate dehydrogenase increased	1,586	42.8 40.7–45.1ROR 44.1 · calibrated p 3e-5 ✓	38.6 EB05 37.0 · IC025 +5.2 3/3 methods agree vs other Complement Inhibitors: PRR 14.0 (12.0–16.3)	Lab value / disease marker	serious PRR 27.4 · 76% consumer	not reported in cached trials
Abdominal pain	1,543	2.6 2.5–2.7ROR 2.6 · calibrated p 0.758	2.6 EB05 2.5 · IC025 +1.3 3/3 methods agree vs other Complement Inhibitors: PRR 20.2 (16.8–24.3)	Labeled adverse reaction exact term	serious PRR 2.2 · 77% consumer	NCT02145182: 3/142 (2.1%) on Eculizumab; 1/146 (0.7%) control (serious AE)

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.

Haptoglobin abnormal — n=48, PRR 416.8
Meningococcal bacteraemia — n=45, PRR 350.9
Haptoglobin decreased — n=235, PRR 161.8
Biopsy bone marrow — n=126, PRR 143.7
C3 glomerulopathy — n=48, PRR 121.4
Blood product transfusion dependent — n=97, PRR 115.1
Haptoglobin increased — n=29, PRR 103.5
Blood product transfusion — n=20, PRR 101.9
Budd-chiari syndrome — n=48, PRR 89.5
Arteriovenous fistula occlusion — n=32, PRR 86.1

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 Eculizumab?

In FDA FAERS, the most frequently co-reported reaction terms for Eculizumab are fatigue, haemoglobin decreased, headache, pyrexia, dyspnoea, asthenia. 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 Eculizumab have an FDA boxed warning?

Yes. The current FDA label carries a boxed warning: SERIOUS MENINGOCOCCAL INFECTIONS SOLIRIS, a complement inhibitor, increases the risk of serious infections caused by Neisseria meningitidis [see Warnings and Precautions (5.1) ] . Life-threatening and fatal meningococcal infections have occurred in patients treated with complement inhibitors.

Do FAERS signals prove that Eculizumab 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 ebcd67fa-b4d1-4a22-b33d-ee8bf6b9c722, effective 20260708; matched on openfda.generic_name.exact:"ECULIZUMAB")
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, field patient.drug.openfda.generic_name.exact, 1,203 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
ClinicalTrials.gov API v2 (query ECULIZUMAB, results-bearing studies sorted by enrollment)

Page generated 2026-10-14. 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.