Velpatasvir

證據等級: L5

預測適應症: 10 個

Velpatasvir: From Hepatitis C to Hepatitis B Virus Infection

One-Sentence Summary

Velpatasvir is an NS5A inhibitor originally developed as part of the sofosbuvir/velpatasvir (Epclusa) combination for chronic hepatitis C virus (HCV) infection. The TxGNN model predicts potential efficacy against hepatitis B virus (HBV) infection with a very high score, but of the 26 clinical trials and 20 publications retrieved for this candidate, virtually all describe HCV treatment — the sole item directly linking the drug to HBV is a case report of HBV reactivation during HCV therapy, which is a safety signal rather than efficacy evidence.

Quick Overview

Item	Content
Original Indication	Chronic Hepatitis C Virus (HCV) infection (component of sofosbuvir/velpatasvir combination)
Predicted New Indication	Hepatitis B Virus Infection
TxGNN Prediction Score	99.87%
Evidence Level	L4
Taiwan Market Status	未上市 (Not marketed)
Number of Authorizations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Formal mechanism-of-action data for velpatasvir is flagged as a data gap in this evidence pack. Based on information embedded in the trial and literature records, however, velpatasvir is a hepatitis C virus (HCV) NS5A inhibitor, marketed in combination with the NS5B polymerase inhibitor sofosbuvir (Epclusa) as a pan-genotypic treatment for chronic HCV infection.

The predicted new indication — hepatitis B virus infection — does not share this mechanistic target. HBV is a hepadnavirus that replicates via reverse transcription of pregenomic RNA and depends on persistent nuclear cccDNA, a biology entirely distinct from the HCV NS5A protein that velpatasvir inhibits. Despite the strong TxGNN score, this prediction most likely reflects surface-level similarity (both are hepatotropic viruses causing chronic liver disease) rather than shared drug-target biology.

Notably, the one piece of literature that directly connects velpatasvir to HBV (PMID 31542053) describes HBV reactivation in a patient who was hepatitis B core antibody-positive while being treated with sofosbuvir/velpatasvir for HCV — a well-recognized DAA-class safety concern about unmasking latent HBV, not evidence of anti-HBV efficacy. This should be read as a caution flag for HBV/HCV co-infected patients, not as support for repurposing velpatasvir to treat HBV.

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT04997564	Phase 4	Unknown	120	SOF/VEL with prophylactic TAF in treatment-naïve HCV/HBV co-infected patients — designed to prevent HBV reactivation during HCV therapy, not to treat HBV itself
NCT03250910	Phase 4	Completed	228	SOF/VEL ± ribavirin in HIV/HCV co-infected patients (graded C: unrelated to HBV)
NCT02996682	Phase 3	Completed	102	SOF/VEL ± ribavirin in HCV decompensated cirrhosis (graded C: unrelated to HBV)
NCT02994056	Phase 2	Completed	32	SOF/VEL + ribavirin in HCV Child-Pugh-Turcotte Class C cirrhosis (graded C: unrelated to HBV)
NCT03823911	Phase 4	Completed	87	Cardiovascular risk outcomes after HCV eradication in HIV co-infected patients
NCT03579576	N/A	Completed	803	Simplified HCV testing/treatment strategy in Myanmar, integrated with HIV care
NCT03086044	Phase 4	Unknown	148	Organ transplantation from HCV-positive donors to HCV-uninfected recipients
NCT03987503	Phase 4	Completed	87	Community-based point-of-diagnosis HCV treatment feasibility study
NCT06180590	N/A	Recruiting	200	Vosevi (SOF/VEL/VOX) efficacy in patients who failed prior DAA therapy for HCV
NCT01457768	N/A	Completed	570	Long-term registry of HCV patients who failed to achieve sustained virologic response

Note: None of these trials directly evaluate velpatasvir for treatment of hepatitis B; HBV appears only as a co-infection or reactivation-monitoring context.

Literature Evidence

PMID	Year	Type	Journal	Key Findings
31542053	2019	Case report	Journal of Medical Case Reports	HBV reactivation (immune-escape mutant) in an HBcAb-positive patient during sofosbuvir/velpatasvir treatment for HCV — a safety signal, not efficacy evidence
35248213	2022	Cohort	Lancet Gastroenterology & Hepatology	SOF/VEL safety/efficacy in treatment-naïve HCV genotype 4 patients in Rwanda (SHARED-3)
35248212	2022	Cohort (pending)	Lancet Gastroenterology & Hepatology	SOF/VEL/VOX re-treatment in HCV patients with prior DAA failure in Rwanda (SHARED-3)
32935438	2021	Pending	Journal of Viral Hepatitis	Simplified HCV treatment strategy in Myanmar; HBV co-infected participants treated concurrently with tenofovir, not velpatasvir
34092970	2021	Pending	World Journal of Gastroenterology	Review of pediatric viral hepatitis management, covering both HBV and HCV DAAs as separate disease entities
40414600	2025	Pending	Annals of Hepatology	Cross-sectional comparison of HBV and HCV antiviral drug pricing (health-economics focus, not efficacy)
33217040	2021	Pending	Journal of Gastroenterology and Hepatology	Real-world SOF/VEL ± ribavirin efficacy/safety in HCV genotype 3
38910758	2024	Pending	Cureus	SOF/VEL efficacy in HCV patients with chronic kidney disease
35579223	2022	Pending	European Journal of General Practice	General review of chronic HCV diagnosis and treatment
31114957	2019	Pending	Clinical Pharmacokinetics	Review of HCV DAA pharmacokinetics/pharmacodynamics, including SOF/VEL

Note: No literature reports velpatasvir being used or studied as a treatment for hepatitis B infection itself.

Taiwan Market Information

Velpatasvir currently holds no marketing authorization in Taiwan (未上市, 0 licenses on record). No product listing or approved indication text is available for review.

Safety Considerations

Formal safety data (warnings, contraindications, drug interactions) are not available in the current evidence pack — please refer to the international package insert (e.g., Epclusa US/EU labeling) for authoritative safety information.
Evidence-derived safety signal: One case report (PMID 31542053) documents HBV reactivation, driven by an HBsAg immune-escape mutant, in a patient who was HBcAb-positive during sofosbuvir/velpatasvir treatment for HCV. This is consistent with the well-established DAA-class warning that HBV/HCV co-infected or HBV-exposed patients require HBV monitoring (and often antiviral prophylaxis, as reflected in NCT04997564) when receiving sofosbuvir/velpatasvir — not an indication that velpatasvir treats HBV.

Conclusion and Next Steps

Decision: Hold

Rationale: Despite a high TxGNN prediction score, there is no mechanistic or empirical basis for velpatasvir as an HBV treatment. All available clinical trial and literature evidence pertains to HCV therapy (with HBV appearing only as a co-infection/reactivation-monitoring context), and the sole HBV-specific literature finding is a reactivation safety signal that argues for caution, not efficacy.

To proceed, the following is needed:

Confirmed mechanism-of-action data (DG002) to formally assess target relevance to HBV
TFDA label warnings/contraindications (DG001) — currently a blocking data gap for any S1 safety review
Preclinical or in vitro evidence of anti-HBV activity for velpatasvir, which does not currently exist in the evidence pack
If pursued at all, reframe the research question toward HBV reactivation risk management in HCV/HBV co-infected patients rather than HBV treatment efficacy

Note: Lower-ranked candidates in this evidence pack (hepatitis E, hepatitis A, HIV, and various zoonotic/rare-disease predictions) show even weaker or no supporting evidence and are not analyzed further in this report; all carry "Hold" recommendations.

Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.