Sparsentan side effects: what 5,865 FDA adverse event reports show
Drug class
Endothelin Receptor Antagonist, Angiotensin 2 Receptor Blocker
Brand names
Filspari
Who reports
5,865 reports · 17% serious · 32 with death outcome · 44% female
Used for
FILSPARI is an endothelin and angiotensin II receptor antagonist indicated: • To slow kidney function decline in adults with primary immunoglobulin A nephropathy (IgAN) who are at risk for disease progression ( 1.1 , 12.1 , 14.1 ). • To reduce proteinuria in adult and pediatric patients aged 8 years and older with focal segmental glomerulosclerosis (FSGS) without nephrotic syndrome ( 1.2 , 12.1 , 14.2 ).
What it is
FILSPARI (sparsentan) is an endothelin and angiotensin II receptor antagonist.
Boxed warning
HEPATOTOXICITY and EMBRYO-FETAL TOXICITY Because of the risk of hepatotoxicity, FILSPARI is available only through a restricted program called the FILSPARI REMS. Under the FILSPARI REMS, prescribers, patients, and pharmacies must enroll in the program [see Warnings and Precautions ( 5.1 , 5.2 )] .
Causality screen of the 40 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.
- 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. 98 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 |
|---|---|---|---|---|---|---|
| Glomerular filtration rate decreased | 217 | 65.2 57.1–74.4ROR 67.7 · χ² 13,411 / p <1e-300 | 63.7 EB05 56.9 · IC025 +5.6 3/3 methods agree | Lab value / disease marker | serious PRR 93.9 · 78% consumer | no trial data cached |
| Product administration error | 324 | 59.0 53.0–65.6ROR 62.4 · χ² 18,123 / p <1e-300 | 57.8 EB05 52.7 · IC025 +5.6 3/3 methods agree | Reporting / coding artifact | serious PRR 21.3 · 96% consumer | no trial data cached |
| Dizziness postural | 106 | 39.9 33.0–48.2ROR 40.6 · χ² 3,937 / p <1e-300 | 39.2 EB05 33.3 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=13 · 92% consumer | no trial data cached |
| Blood potassium increased | 175 | 39.0 33.6–45.1ROR 40.1 · χ² 6,370 / p <1e-300 | 38.4 EB05 33.9 · IC025 +4.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 35.8 · 88% consumer | no trial data cached |
| Proteinuria | 142 | 27.1 23.0–31.9ROR 27.8 · χ² 3,522 / p <1e-300 | 26.8 EB05 23.3 · IC025 +4.3 3/3 methods agree | Likely indication confounding term in indications | serious PRR 27.3 | no trial data cached |
| Contraindicated product administered | 111 | 13.2 11.0–15.9ROR 13.4 · χ² 1,237 / p 4e-271 | 13.1 EB05 11.1 · IC025 +3.3 3/3 methods agree | Reporting / coding artifact | serious PRR 16.9 | no trial data cached |
| Renal pain | 37 | 12.6 9.1–17.3ROR 12.6 · χ² 381 / p 4e-85 | 12.2 EB05 9.0 · IC025 +2.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 8.7 · ♀ 64% (drug 44%) · 84% consumer | no trial data cached |
| Chromaturia | 75 | 11.9 9.5–14.9ROR 12.0 · χ² 737 / p 2e-162 | 11.7 EB05 9.6 · IC025 +3.1 3/3 methods agree | Not in label — unassessed | serious PRR 6.1 · 87% consumer | no trial data cached |
| Blood urea increased | 55 | 11.7 9.0–15.2ROR 11.8 · χ² 527 / p 7e-117 | 11.4 EB05 9.0 · IC025 +3.0 3/3 methods agree | Lab value / disease marker | serious PRR 15.5 | no trial data cached |
| Blood pressure decreased | 215 | 11.6 10.2–13.3ROR 12.0 · χ² 2,077 / p <1e-300 | 11.5 EB05 10.3 · IC025 +3.3 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.7 · 94% consumer | no trial data cached |
| Hypotension (low blood pressure) | 644 | 11.5 10.7–12.4ROR 12.8 · χ² 6,221 / p <1e-300 | 11.5 EB05 10.7 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.7 · 81% consumer | no trial data cached |
| Drug effect less than expected | 45 | 11.4 8.5–15.3ROR 11.5 · χ² 417 / p 5e-93 | 11.1 EB05 8.4 · IC025 +2.9 3/3 methods agree | Reporting / coding artifact | serious n=5 · 87% consumer | no trial data cached |
| Liver function test increased | 68 | 11.4 9.0–14.5ROR 11.6 · χ² 635 / p 2e-140 | 11.2 EB05 9.0 · IC025 +3.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 10.0 | no trial data cached |
| Blood creatinine increased | 196 | 10.7 9.4–12.3ROR 11.1 · χ² 1,721 / p <1e-300 | 10.6 EB05 9.4 · IC025 +3.1 3/3 methods agree | Lab value / disease marker | serious PRR 13.1 | no trial data cached |
| Gout | 53 | 10.6 8.1–13.8ROR 10.7 · χ² 449 / p 6e-100 | 10.2 EB05 8.0 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 7.3 · ♀ 23% (drug 44%) · 81% consumer | no trial data cached |
| Blood pressure abnormal | 45 | 8.1 6.1–10.9ROR 8.2 · χ² 274 / p 7e-62 | 7.7 EB05 5.9 · IC025 +2.4 3/3 methods agree | Lab value / disease marker | serious PRR 5.5 · 89% consumer | no trial data cached |
| Laboratory test abnormal | 66 | 8.0 6.3–10.2ROR 8.1 · χ² 398 / p 7e-89 | 7.7 EB05 6.2 · IC025 +2.5 3/3 methods agree | Reporting / coding artifact | serious PRR 8.0 · 88% consumer | no trial data cached |
| Flank pain | 20 | 7.7 4.9–11.9ROR 7.7 · χ² 109 / p 8e-26 | 6.7 EB05 4.5 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 7.0 · 85% consumer | no trial data cached |
| Dialysis | 30 | 7.6 5.3–10.8ROR 7.6 · χ² 164 / p 8e-38 | 6.9 EB05 5.0 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 15.6 · 73% consumer | no trial data cached |
| Peripheral swelling | 315 | 7.4 6.6–8.2ROR 7.7 · χ² 1,731 / p <1e-300 | 7.3 EB05 6.6 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 7.6 · 93% consumer | no trial data cached |
| Blood urine present | 36 | 6.8 4.9–9.4ROR 6.8 · χ² 171 / p 2e-39 | 6.3 EB05 4.7 · IC025 +2.1 3/3 methods agree | Lab value / disease marker | serious PRR 7.4 · ♀ 74% (drug 44%) | no trial data cached |
| Renal impairment | 155 | 6.6 5.7–7.7ROR 6.8 · χ² 737 / p 1e-162 | 6.5 EB05 5.7 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 12.0 · 92% consumer | no trial data cached |
| Brain fog | 27 | 6.6 4.5–9.7ROR 6.7 · χ² 123 / p 6e-29 | 6.0 EB05 4.3 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 11.5 · 96% consumer | no trial data cached |
| Hyperkalaemia (high potassium) | 61 | 6.3 4.9–8.0ROR 6.3 · χ² 264 / p 1e-59 | 6.0 EB05 4.8 · IC025 +2.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 14.2 | no trial data cached |
| Dizziness | 837 | 6.0 5.7–6.4ROR 6.9 · χ² 3,576 / p <1e-300 | 6.0 EB05 5.7 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.6 · 89% consumer | no trial data cached |
| Fluid retention | 85 | 6.0 4.8–7.4ROR 6.1 · χ² 348 / p 5e-78 | 5.8 EB05 4.8 · IC025 +2.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 8.5 · 92% consumer | no trial data cached |
| Orthostatic hypotension (dizziness on standing) | 29 | 5.9 4.1–8.6ROR 6.0 · χ² 114 / p 5e-27 | 5.5 EB05 4.0 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 0.8 · 72% consumer | no trial data cached |
| Hunger | 22 | 5.9 3.9–8.9ROR 5.9 · χ² 84 / p 3e-20 | 5.3 EB05 3.7 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious n=3 · ♀ 76% (drug 44%) · 100% consumer | no trial data cached |
| Hepatic enzyme increased | 105 | 5.5 4.6–6.7ROR 5.6 · χ² 386 / p 3e-86 | 5.4 EB05 4.6 · IC025 +2.1 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 6.9 · 79% consumer | no trial data cached |
| Product use in unapproved indication | 359 | 5.3 4.8–5.8ROR 5.5 · χ² 1,247 / p 2e-273 | 5.2 EB05 4.8 · IC025 +2.2 3/3 methods agree | Reporting / coding artifact | serious PRR 3.1 · 82% consumer | no trial data cached |
| Illness | 146 | 5.2 4.4–6.1ROR 5.3 · χ² 493 / p 2e-109 | 5.1 EB05 4.5 · IC025 +2.1 3/3 methods agree | Reporting / coding artifact | serious PRR 6.3 · 91% consumer | no trial data cached |
| Aspartate aminotransferase increased | 76 | 5.1 4.1–6.4ROR 5.2 · χ² 248 / p 3e-56 | 5.0 EB05 4.1 · IC025 +1.9 3/3 methods agree | Labeled — boxed warning synonym match | serious PRR 10.2 | no trial data cached |
| Pollakiuria (frequent urination) | 59 | 5.1 3.9–6.5ROR 5.1 · χ² 189 / p 3e-43 | 4.9 EB05 3.9 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 5.4 · 95% consumer | no trial data cached |
| Generalised oedema | 17 | 4.9 3.1–7.9ROR 5.0 · χ² 50 / p 1e-12 | 4.4 EB05 2.9 · IC025 +1.3 3/3 methods agree | Not in label — unassessed | serious PRR 4.5 | no trial data cached |
| Blood iron decreased | 16 | 4.9 3.0–7.9ROR 4.9 · χ² 45 / p 9e-12 | 4.3 EB05 2.8 · IC025 +1.3 3/3 methods agree | Lab value / disease marker | serious PRR 5.7 | no trial data cached |
| Prescribed underdose | 27 | 4.8 3.3–7.1ROR 4.9 · χ² 79 / p 4e-19 | 4.5 EB05 3.2 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 10.7 · 93% consumer | no trial data cached |
| Joint swelling | 162 | 4.8 4.1–5.6ROR 4.9 · χ² 488 / p 2e-108 | 4.7 EB05 4.2 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.1 · 94% consumer | no trial data cached |
| Blood pressure fluctuation | 32 | 4.8 3.4–6.7ROR 4.8 · χ² 91 / p 6e-22 | 4.5 EB05 3.3 · IC025 +1.6 3/3 methods agree | Lab value / disease marker | serious PRR 5.9 · 84% consumer | no trial data cached |
| Presyncope (near-fainting) | 32 | 4.7 3.3–6.7ROR 4.8 · χ² 90 / p 9e-22 | 4.4 EB05 3.3 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 2.6 · 97% consumer | no trial data cached |
| Thirst | 23 | 4.6 3.1–6.9ROR 4.6 · χ² 62 / p 2e-15 | 4.2 EB05 3.0 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious PRR 6.5 · 91% consumer | 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 |
|---|---|---|---|---|---|---|
| Dizziness | 837 | 6.0 5.7–6.4ROR 6.9 · χ² 3,576 / p <1e-300 | 6.0 EB05 5.7 · IC025 +2.5 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.6 · 89% consumer | no trial data cached |
| Fatigue (tiredness) | 780 | 3.6 3.4–3.8ROR 4.0 · χ² 1,511 / p <1e-300 | 3.6 EB05 3.4 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.1 · 91% consumer | no trial data cached |
| Hypotension (low blood pressure) | 644 | 11.5 10.7–12.4ROR 12.8 · χ² 6,221 / p <1e-300 | 11.5 EB05 10.7 · IC025 +3.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 7.7 · 81% consumer | no trial data cached |
| Nausea | 399 | 1.8 1.6–2.0ROR 1.9 · χ² 149 / p 2e-34 | 1.8 EB05 1.7 · IC025 +0.7 | Labeled adverse reaction exact term | serious PRR 1.3 · ♀ 64% (drug 44%) · 90% consumer | no trial data cached |
| Product use in unapproved indication | 359 | 5.3 4.8–5.8ROR 5.5 · χ² 1,247 / p 2e-273 | 5.2 EB05 4.8 · IC025 +2.2 3/3 methods agree | Reporting / coding artifact | serious PRR 3.1 · 82% consumer | no trial data cached |
| Headache | 345 | 2.0 1.8–2.2ROR 2.0 · χ² 169 / p 7e-39 | 2.0 EB05 1.8 · IC025 +0.8 | Not in label — unassessed | serious PRR 1.7 · 89% consumer | no trial data cached |
| Product administration error | 324 | 59.0 53.0–65.6ROR 62.4 · χ² 18,123 / p <1e-300 | 57.8 EB05 52.7 · IC025 +5.6 3/3 methods agree | Reporting / coding artifact | serious PRR 21.3 · 96% consumer | no trial data cached |
| Peripheral swelling | 315 | 7.4 6.6–8.2ROR 7.7 · χ² 1,731 / p <1e-300 | 7.3 EB05 6.6 · IC025 +2.7 3/3 methods agree | Not in label — unassessed | serious PRR 7.6 · 93% consumer | no trial data cached |
| Pruritus (itching) | 285 | 2.7 2.4–3.0ROR 2.8 · χ² 308 / p 3e-69 | 2.7 EB05 2.4 · IC025 +1.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 2.0 · 94% consumer | no trial data cached |
| Product dose omission issue | 268 | 3.4 3.0–3.8ROR 3.5 · χ² 449 / p 5e-100 | 3.3 EB05 3.0 · IC025 +1.5 3/3 methods agree | Reporting / coding artifact | serious PRR 5.3 · 89% consumer | no trial data cached |
| Glomerular filtration rate decreased | 217 | 65.2 57.1–74.4ROR 67.7 · χ² 13,411 / p <1e-300 | 63.7 EB05 56.9 · IC025 +5.6 3/3 methods agree | Lab value / disease marker | serious PRR 93.9 · 78% consumer | no trial data cached |
| Blood pressure decreased | 215 | 11.6 10.2–13.3ROR 12.0 · χ² 2,077 / p <1e-300 | 11.5 EB05 10.3 · IC025 +3.3 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.7 · 94% consumer | no trial data cached |
| Blood creatinine increased | 196 | 10.7 9.4–12.3ROR 11.1 · χ² 1,721 / p <1e-300 | 10.6 EB05 9.4 · IC025 +3.1 3/3 methods agree | Lab value / disease marker | serious PRR 13.1 | no trial data cached |
| Hypertension (high blood pressure) | 188 | 3.2 2.8–3.7ROR 3.2 · χ² 280 / p 4e-63 | 3.1 EB05 2.8 · IC025 +1.4 3/3 methods agree | Not in label — unassessed | serious PRR 3.7 · 90% consumer | no trial data cached |
| Blood potassium increased | 175 | 39.0 33.6–45.1ROR 40.1 · χ² 6,370 / p <1e-300 | 38.4 EB05 33.9 · IC025 +4.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 35.8 · 88% consumer | 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.
- Dizziness postural — n=106, PRR 39.9
- Chromaturia — n=75, PRR 11.9
- Gout — n=53, PRR 10.6
- Flank pain — n=20, PRR 7.7
- Dialysis — n=30, PRR 7.6
- Peripheral swelling — n=315, PRR 7.4
- Renal impairment — n=155, PRR 6.6
- Brain fog — n=27, PRR 6.6
- Hunger — n=22, PRR 5.9
- Pollakiuria — n=59, PRR 5.1
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 Sparsentan?
In FDA FAERS, the most frequently co-reported reaction terms for Sparsentan are dizziness, fatigue, hypotension, nausea, headache, peripheral 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 Sparsentan have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: HEPATOTOXICITY and EMBRYO-FETAL TOXICITY Because of the risk of hepatotoxicity, FILSPARI is available only through a restricted program called the FILSPARI REMS. Under the FILSPARI REMS, prescribers, patients, and pharmacies must enroll in the program [see Warnings and Precautions ( 5.1 , 5.2 )] .
Do FAERS signals prove that Sparsentan 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 d7354af1-f304-f4d9-e053-2995a90ab219, effective 20260409; matched on
openfda.generic_name.exact:"SPARSENTAN") - 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, 138 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.