Maribavir side effects: what 2,407 FDA adverse event reports show
Drug class
Cytomegalovirus pUL97 Kinase Inhibitor
Brand names
Livtencity
Who reports
2,407 reports · 86% serious · 526 with death outcome · 43% female
Used for
LIVTENCITY ® is indicated for the treatment of adults and pediatric patients (12 years of age and older and weighing at least 35 kg) with post-transplant cytomegalovirus (CMV) infection/disease that is refractory to treatment (with or without genotypic resistance) with ganciclovir, valganciclovir, cidofovir or foscarnet .
What it is
LIVTENCITY tablets contain maribavir, a benzimidazole riboside CMV pUL97 protein kinase inhibitor.
Boxed warning
None in the current label
Causality screen of the 33 strongest signals
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.
- 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.
- Outcome field, not a reaction Death is a report outcome, not a reaction term. It is dominated by the underlying illness; see the seriousness profile and the boxed warning instead.
- 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. 15 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 |
|---|---|---|---|---|---|---|
| Taste disorder | 229 | 100.6 88.8–113.9ROR 111.0 · χ² 22,237 / p <1e-300 | 98.6 EB05 88.4 · IC025 +6.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 97.6 | no trial data cached |
| Cytomegalovirus infection | 186 | 98.4 85.6–113.1ROR 106.5 · χ² 17,645 / p <1e-300 | 96.3 EB05 85.3 · IC025 +6.0 3/3 methods agree | Likely indication confounding term in indications | serious PRR 63.9 | no trial data cached |
| Drug resistance | 177 | 60.4 52.4–69.6ROR 65.1 · χ² 10,216 / p <1e-300 | 59.6 EB05 52.6 · IC025 +5.4 3/3 methods agree | Reporting / coding artifact | serious PRR 37.5 | no trial data cached |
| Dysgeusia (altered taste) | 265 | 31.0 27.6–34.7ROR 34.7 · χ² 7,658 / p <1e-300 | 30.8 EB05 27.8 · IC025 +4.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 46.3 | no trial data cached |
| Insurance issue | 37 | 21.7 15.8–29.9ROR 22.0 · χ² 710 / p 1e-156 | 21.5 EB05 16.2 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 26.8 | no trial data cached |
| Inability to afford medication | 17 | 15.1 9.4–24.2ROR 15.2 · χ² 209 / p 1e-47 | 14.3 EB05 8.9 · IC025 +2.6 3/3 methods agree | Not in label — unassessed | serious n=16 | no trial data cached |
| Thrombotic microangiopathy | 15 | 13.5 8.1–22.4ROR 13.6 · χ² 161 / p 3e-37 | 12.4 EB05 7.3 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 9.0 | no trial data cached |
| Hospitalisation | 223 | 12.8 11.3–14.5ROR 13.9 · χ² 2,417 / p <1e-300 | 12.7 EB05 11.3 · IC025 +3.4 3/3 methods agree | Reporting / coding artifact | serious PRR 8.7 | no trial data cached |
| Product availability issue | 27 | 10.5 7.2–15.3ROR 10.6 · χ² 222 / p 1e-50 | 9.8 EB05 6.8 · IC025 +2.5 3/3 methods agree | Reporting / coding artifact | serious PRR 13.0 | no trial data cached |
| Ageusia (loss of taste) | 27 | 9.4 6.5–13.7ROR 9.5 · χ² 194 / p 2e-44 | 8.6 EB05 6.0 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 12.8 | no trial data cached |
| Bacteraemia | 12 | 8.9 5.0–15.6ROR 8.9 · χ² 76 / p 1e-18 | 7.2 EB05 4.2 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 6.0 | no trial data cached |
| Bacterial infection | 18 | 8.4 5.3–13.4ROR 8.5 · χ² 111 / p 3e-26 | 7.3 EB05 4.8 · IC025 +2.0 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.5 | no trial data cached |
| Full blood count decreased | 19 | 8.2 5.2–12.8ROR 8.3 · χ² 113 / p 1e-26 | 7.2 EB05 4.7 · IC025 +2.0 3/3 methods agree | Lab value / disease marker | serious PRR 7.5 | no trial data cached |
| Product taste abnormal | 12 | 7.8 4.4–13.7ROR 7.8 · χ² 64 / p 6e-16 | 6.3 EB05 3.7 · IC025 +1.6 3/3 methods agree | Reporting / coding artifact | serious n=7 | no trial data cached |
| Multiple organ dysfunction syndrome | 21 | 6.6 4.3–10.0ROR 6.6 · χ² 93 / p 2e-22 | 5.8 EB05 4.0 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 4.4 · 90% clinician | no trial data cached |
| Product prescribing issue | 15 | 6.4 3.9–10.6ROR 6.5 · χ² 63 / p 9e-16 | 5.5 EB05 3.5 · IC025 +1.6 3/3 methods agree | Reporting / coding artifact | serious PRR 11.3 | no trial data cached |
| Renal disorder | 34 | 6.3 4.5–8.9ROR 6.4 · χ² 148 / p 3e-34 | 5.9 EB05 4.4 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 | no trial data cached |
| Product use issue | 136 | 6.3 5.4–7.5ROR 6.7 · χ² 610 / p 4e-135 | 6.2 EB05 5.4 · IC025 +2.4 3/3 methods agree | Reporting / coding artifact | serious PRR 8.7 | no trial data cached |
| Blood test abnormal | 10 | 6.2 3.3–11.5ROR 6.2 · χ² 39 / p 3e-10 | 5.0 EB05 2.9 · IC025 +1.2 3/3 methods agree | Reporting / coding artifact | serious PRR 5.7 | no trial data cached |
| Drug level increased | 11 | 5.8 3.2–10.4ROR 5.8 · χ² 39 / p 2e-10 | 4.8 EB05 2.8 · IC025 +1.2 3/3 methods agree | Reporting / coding artifact | serious PRR 3.9 | no trial data cached |
| Pancytopenia (all blood cells low) | 36 | 5.6 4.1–7.8ROR 5.7 · χ² 133 / p 6e-31 | 5.3 EB05 4.0 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 3.8 | no trial data cached |
| Septic shock | 26 | 5.2 3.6–7.7ROR 5.3 · χ² 85 / p 1e-20 | 4.8 EB05 3.5 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 3.5 · ♀ 23% (drug 43%) | no trial data cached |
| Leukopenia (low white blood cells) | 30 | 5.2 3.7–7.5ROR 5.3 · χ² 99 / p 1e-23 | 4.9 EB05 3.6 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 3.5 | no trial data cached |
| Acute respiratory distress syndrome | 10 | 4.9 2.7–9.1ROR 4.9 · χ² 27 / p 8e-8 | 4.1 EB05 2.4 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 3.3 | no trial data cached |
| Clostridium difficile infection | 12 | 4.8 2.7–8.5ROR 4.8 · χ² 33 / p 6e-9 | 4.1 EB05 2.5 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 3.4 | no trial data cached |
| Viral infection | 17 | 4.5 2.8–7.1ROR 4.5 · χ² 42 / p 4e-11 | 4.0 EB05 2.7 · IC025 +1.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.7 | no trial data cached |
| Kidney infection | 10 | 4.4 2.4–8.2ROR 4.5 · χ² 23 / p 7e-7 | 3.8 EB05 2.2 · IC025 +0.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 3.3 | no trial data cached |
| Blood pressure abnormal | 10 | 4.4 2.4–8.2ROR 4.4 · χ² 23 / p 8e-7 | 3.7 EB05 2.2 · IC025 +0.8 3/3 methods agree | Lab value / disease marker | serious PRR 4.3 | no trial data cached |
| White blood cell count decreased | 42 | 3.4 2.5–4.5ROR 3.4 · χ² 68 / p 8e-17 | 3.3 EB05 2.5 · IC025 +1.2 3/3 methods agree | Lab value / disease marker | serious PRR 2.8 | no trial data cached |
| Death | 318 | 3.2 2.9–3.6ROR 3.5 · χ² 503 / p 1e-111 | 3.2 EB05 2.9 · IC025 +1.5 3/3 methods agree | Outcome field, not a reaction | serious PRR 2.2 | no trial data cached |
| Therapy interrupted | 21 | 2.6 1.7–4.1ROR 2.7 · χ² 20 / p 4e-6 | 2.5 EB05 1.8 · IC025 +0.6 | Reporting / coding artifact | serious PRR 3.7 | no trial data cached |
| Myelosuppression | 10 | 2.6 1.4–4.7ROR 2.6 · χ² 8 / p 0.002 | 2.4 EB05 1.4 · IC025 +0.2 | Not in label — unassessed | serious PRR 1.7 | no trial data cached |
| No adverse event | 49 | 2.4 1.8–3.2ROR 2.4 · χ² 39 / p 2e-10 | 2.4 EB05 1.9 · IC025 +0.8 | Reporting / coding artifact | serious PRR 13.5 | 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 |
|---|---|---|---|---|---|---|
| Death | 318 | 3.2 2.9–3.6ROR 3.5 · χ² 503 / p 1e-111 | 3.2 EB05 2.9 · IC025 +1.5 3/3 methods agree | Outcome field, not a reaction | serious PRR 2.2 | no trial data cached |
| Dysgeusia (altered taste) | 265 | 31.0 27.6–34.7ROR 34.7 · χ² 7,658 / p <1e-300 | 30.8 EB05 27.8 · IC025 +4.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 46.3 | no trial data cached |
| Taste disorder | 229 | 100.6 88.8–113.9ROR 111.0 · χ² 22,237 / p <1e-300 | 98.6 EB05 88.4 · IC025 +6.1 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 97.6 | no trial data cached |
| Hospitalisation | 223 | 12.8 11.3–14.5ROR 13.9 · χ² 2,417 / p <1e-300 | 12.7 EB05 11.3 · IC025 +3.4 3/3 methods agree | Reporting / coding artifact | serious PRR 8.7 | no trial data cached |
| Cytomegalovirus infection | 186 | 98.4 85.6–113.1ROR 106.5 · χ² 17,645 / p <1e-300 | 96.3 EB05 85.3 · IC025 +6.0 3/3 methods agree | Likely indication confounding term in indications | serious PRR 63.9 | no trial data cached |
| Drug resistance | 177 | 60.4 52.4–69.6ROR 65.1 · χ² 10,216 / p <1e-300 | 59.6 EB05 52.6 · IC025 +5.4 3/3 methods agree | Reporting / coding artifact | serious PRR 37.5 | no trial data cached |
| Product use issue | 136 | 6.3 5.4–7.5ROR 6.7 · χ² 610 / p 4e-135 | 6.2 EB05 5.4 · IC025 +2.4 3/3 methods agree | Reporting / coding artifact | serious PRR 8.7 | no trial data cached |
| No adverse event | 49 | 2.4 1.8–3.2ROR 2.4 · χ² 39 / p 2e-10 | 2.4 EB05 1.9 · IC025 +0.8 | Reporting / coding artifact | serious PRR 13.5 | no trial data cached |
| White blood cell count decreased | 42 | 3.4 2.5–4.5ROR 3.4 · χ² 68 / p 8e-17 | 3.3 EB05 2.5 · IC025 +1.2 3/3 methods agree | Lab value / disease marker | serious PRR 2.8 | no trial data cached |
| Insurance issue | 37 | 21.7 15.8–29.9ROR 22.0 · χ² 710 / p 1e-156 | 21.5 EB05 16.2 · IC025 +3.5 3/3 methods agree | Not in label — unassessed | serious PRR 26.8 | no trial data cached |
| Pancytopenia (all blood cells low) | 36 | 5.6 4.1–7.8ROR 5.7 · χ² 133 / p 6e-31 | 5.3 EB05 4.0 · IC025 +1.8 3/3 methods agree | Not in label — unassessed | serious PRR 3.8 | no trial data cached |
| Renal disorder | 34 | 6.3 4.5–8.9ROR 6.4 · χ² 148 / p 3e-34 | 5.9 EB05 4.4 · IC025 +2.0 3/3 methods agree | Not in label — unassessed | serious PRR 4.9 | no trial data cached |
| Leukopenia (low white blood cells) | 30 | 5.2 3.7–7.5ROR 5.3 · χ² 99 / p 1e-23 | 4.9 EB05 3.6 · IC025 +1.7 3/3 methods agree | Not in label — unassessed | serious PRR 3.5 | no trial data cached |
| Ageusia (loss of taste) | 27 | 9.4 6.5–13.7ROR 9.5 · χ² 194 / p 2e-44 | 8.6 EB05 6.0 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 12.8 | no trial data cached |
| Product availability issue | 27 | 10.5 7.2–15.3ROR 10.6 · χ² 222 / p 1e-50 | 9.8 EB05 6.8 · IC025 +2.5 3/3 methods agree | Reporting / coding artifact | serious PRR 13.0 | 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.
- Insurance issue — n=37, PRR 21.7
- Multiple organ dysfunction syndrome — n=21, PRR 6.6
- Renal disorder — n=34, PRR 6.3
- Pancytopenia — n=36, PRR 5.6
- Septic shock — n=26, PRR 5.2
- Leukopenia — n=30, PRR 5.2
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 Maribavir?
In FDA FAERS, the most frequently co-reported reaction terms for Maribavir are dysgeusia, taste disorder, cytomegalovirus infection, white blood cell count decreased, insurance issue, pancytopenia. 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 Maribavir have an FDA boxed warning?
No. The FDA label retrieved for Maribavir has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Maribavir 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 c94fc2c5-e840-4f18-b7d8-d5eacb26d3a0, effective 20260127; matched on
openfda.generic_name.exact:"MARIBAVIR") - 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, 48 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.