Sofosbuvir, Velpatasvir and Voxilaprevir side effects: what 1,084 FDA adverse event reports show

Sofosbuvir, Velpatasvir, And Voxilaprevir · Sovaldi · 7 reaction terms · 278 drug–reaction co-reports · data 2026-09-14

Drug class

Hepatitis C Virus Nucleotide Analog NS5B Polymerase Inhibitor

FDA label (Established Pharmacologic Class)

Brand names

Sovaldi

openFDA label

Who reports

1,084 reports · 37% serious · 35 with death outcome · 29% female

openFDA FAERS counts, all years, deduplication not applied

Used for

SOVALDI is a hepatitis C virus (HCV) nucleotide analog NS5B polymerase inhibitor indicated for the treatment of: Adult patients with genotype 1, 2, 3 or 4 chronic HCV infection without cirrhosis or with compensated cirrhosis as a component of a combination antiviral treatment regimen.

FDA label, Indications and Usage

What it is

SOVALDI (sofosbuvir) is a nucleotide analog inhibitor of HCV NS5B polymerase. The IUPAC name for sofosbuvir is ( S )-isopropyl 2-(( S )-(((2 R ,3 R ,4 R ,5 R )-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2 H )-yl)-4-fluoro-3-hydroxy-4-methyltetrahydrofuran-2-yl)methoxy)-(phenoxy)phosphorylamino)propanoate.

FDA label, Description section

Boxed warning

RISK OF HEPATITIS B VIRUS REACTIVATION IN PATIENTS COINFECTED WITH HCV AND HBV Test all patients for evidence of current or prior hepatitis B virus (HBV) infection before initiating treatment with SOVALDI. HBV reacti.

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 7 strongest signals

Likely indication confounding 2Reporting / coding artifact 4Not in label — unassessed 1

What the badges mean

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.
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. 0 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
Hepatitis c	91	145.2 119.2–176.9ROR 158.4 · χ² 12,797 / p <1e-300	139.9 EB05 117.4 · IC025 +6.0 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 237.2 · 94% clinician	no trial data cached
Treatment failure	115	27.1 22.8–32.3ROR 30.2 · χ² 2,876 / p <1e-300	27.0 EB05 23.1 · IC025 +4.3 3/3 methods agree	Reporting / coding artifact	serious PRR 71.2 · 96% clinician	no trial data cached
Hepatic cirrhosis	16	16.6 10.2–27.0ROR 16.8 · χ² 219 / p 8e-50	15.9 EB05 9.8 · IC025 +2.7 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious PRR 24.2	no trial data cached
Product use complaint	11	13.7 7.6–24.7ROR 13.9 · χ² 117 / p 1e-27	12.1 EB05 6.3 · IC025 +2.1 3/3 methods agree	Reporting / coding artifact	serious n=1	no trial data cached
Intentional dose omission	19	13.4 8.6–21.0ROR 13.7 · χ² 207 / p 3e-47	12.7 EB05 8.1 · IC025 +2.6 3/3 methods agree	Reporting / coding artifact	serious PRR 6.7	no trial data cached
Product dose omission	20	5.8 3.8–9.0ROR 5.9 · χ² 76 / p 2e-18	5.2 EB05 3.6 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	serious PRR 5.5	no trial data cached
Hepatic cancer	6	4.8 2.2–10.6ROR 4.8 · χ² 14 / p 7e-5	3.7 EB05 1.9 · IC025 +0.5	Not in label — unassessed	serious PRR 7.4	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
Treatment failure	115	27.1 22.8–32.3ROR 30.2 · χ² 2,876 / p <1e-300	27.0 EB05 23.1 · IC025 +4.3 3/3 methods agree	Reporting / coding artifact	serious PRR 71.2 · 96% clinician	no trial data cached
Hepatitis c	91	145.2 119.2–176.9ROR 158.4 · χ² 12,797 / p <1e-300	139.9 EB05 117.4 · IC025 +6.0 3/3 methods agree	Likely indication confounding term in indications; also in warnings	serious PRR 237.2 · 94% clinician	no trial data cached
Product dose omission	20	5.8 3.8–9.0ROR 5.9 · χ² 76 / p 2e-18	5.2 EB05 3.6 · IC025 +1.6 3/3 methods agree	Reporting / coding artifact	serious PRR 5.5	no trial data cached
Intentional dose omission	19	13.4 8.6–21.0ROR 13.7 · χ² 207 / p 3e-47	12.7 EB05 8.1 · IC025 +2.6 3/3 methods agree	Reporting / coding artifact	serious PRR 6.7	no trial data cached
Hepatic cirrhosis	16	16.6 10.2–27.0ROR 16.8 · χ² 219 / p 8e-50	15.9 EB05 9.8 · IC025 +2.7 3/3 methods agree	Likely indication confounding shares a disease stem with the indications wording	serious PRR 24.2	no trial data cached
Product use complaint	11	13.7 7.6–24.7ROR 13.9 · χ² 117 / p 1e-27	12.1 EB05 6.3 · IC025 +2.1 3/3 methods agree	Reporting / coding artifact	serious n=1	no trial data cached
Hepatic cancer	6	4.8 2.2–10.6ROR 4.8 · χ² 14 / p 7e-5	3.7 EB05 1.9 · IC025 +0.5	Not in label — unassessed	serious PRR 7.4	no trial data cached

Unlabeled candidate signals

Every screened signal with n ≥ 20 was either labeled, an indication term, or an artifact pattern — no unlabeled candidate stood out in the top signals.

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 Sofosbuvir?

In FDA FAERS, the most frequently co-reported reaction terms for Sofosbuvir are hepatitis c, hepatic cirrhosis, hepatic cancer. 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 Sofosbuvir have an FDA boxed warning?

Yes. The current FDA label carries a boxed warning: RISK OF HEPATITIS B VIRUS REACTIVATION IN PATIENTS COINFECTED WITH HCV AND HBV Test all patients for evidence of current or prior hepatitis B virus (HBV) infection before initiating treatment with SOVALDI. HBV reacti.

Do FAERS signals prove that Sofosbuvir 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 80beab2c-396e-4a37-a4dc-40fdb62859cf, effective 20241226; matched on openfda.generic_name.exact:"SOFOSBUVIR")
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, 7 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.