Pibrentasvir

證據等級: L5

預測適應症: 10 個

Pibrentasvir: From Hepatitis C Virus Infection to Hepatitis B Virus Infection

One-Sentence Summary

Pibrentasvir is an NS5A inhibitor marketed only as part of the fixed-dose combination glecaprevir/pibrentasvir, used to treat chronic Hepatitis C virus (HCV) infection. The TxGNN model predicts it may also be effective for Hepatitis B virus infection, with a very high similarity score (99.84%), but on inspection none of the 14 supporting clinical trials or 20 literature citations actually test pibrentasvir against HBV — all are HCV studies. This prediction should be treated as a likely knowledge-graph artifact rather than a genuine repurposing signal.

Quick Overview

Item	Content
Original Indication	Chronic Hepatitis C virus (HCV) infection, genotype 1–6 (as component of glecaprevir/pibrentasvir combination)
Predicted New Indication	Hepatitis B virus infection
TxGNN Prediction Score	99.84%
Evidence Level	L5 (model prediction only — no study directly evaluates pibrentasvir in HBV)
Norway Market Status	✗ Not marketed
Number of Authorizations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data for pibrentasvir is not available from the structured DrugBank record (Data Gap). Based on known information, pibrentasvir is the NS5A-inhibitor component of the fixed-dose combination glecaprevir/pibrentasvir (Maviret/Mavyret), and its efficacy has been established specifically for chronic HCV infection through the large ENDURANCE, EXPEDITION, SURVEYOR, and CERTAIN Phase 2/3 programs.

Mechanistically, pibrentasvir is highly selective for the HCV NS5A protein, which is essential for HCV replication-complex assembly and virion packaging. HBV is a hepadnavirus that replicates via reverse transcription of a pregenomic RNA using its own polymerase and does not encode an NS5A homolog — there is no known molecular target shared between the two viruses. Consistent with this, every clinical trial and nearly every publication retrieved under this "predicted indication" is in fact an HCV trial (in some cases in patients co-infected with, or screened for, HBV/HIV as a safety consideration), not a trial evaluating antiviral activity against HBV itself.

This pattern is not isolated to HBV: the same evidence pack shows equally high TxGNN scores for HIV, hepatitis A, hepatitis E, animal viral hepatitis, Omsk hemorrhagic fever, Kyasanur forest disease, simian/feline immunodeficiency virus infection, and even an unrelated rare neurodevelopmental disorder — none supported by mechanistically plausible or disease-specific evidence. This suggests the model is clustering pibrentasvir with a broad "viral hepatitis / co-infection" node neighborhood in the knowledge graph rather than identifying a real pharmacological relationship to HBV.

Clinical Trial Evidence

All trials below were retrieved as "top evidence" for the HBV prediction, but per the evidence pack's own relevance grading (grade C), every one is actually an HCV trial for glecaprevir/pibrentasvir — none enrolled or evaluated HBV-infected patients for antiviral efficacy.

Trial Number	Phase	Status	Enrollment	Key Findings
NCT01995071	Phase 2	Completed	89	Dose-ranging safety/antiviral activity of ABT-493+ABT-530 (glecaprevir/pibrentasvir) in HCV genotype 1 — not an HBV trial
NCT02640157	Phase 3	Completed	506	ENDURANCE-3: G/P vs sofosbuvir+daclatasvir in HCV genotype 3 — not an HBV trial
NCT03823911	Phase 4	Completed	87	Cardiovascular outcomes after HCV cure in HIV co-infected patients — not an HBV trial
NCT02707952	Phase 3	Completed	295	CERTAIN-1: G/P efficacy/safety in Japanese HCV patients — not an HBV trial
NCT03092375	Phase 3	Completed	177	G/P ± ribavirin in NS5A-inhibitor-experienced HCV GT1 patients — not an HBV trial
NCT03219216	Phase 3	Completed	100	G/P in treatment-naïve Brazilian HCV GT1–6 patients — not an HBV trial
NCT02441283	Phase 2/3	Completed	384	Long-term durability/resistance follow-up of glecaprevir/pibrentasvir in HCV — not an HBV trial
NCT02446717	Phase 2/3	Completed	141	G/P ± ribavirin in HCV patients who failed prior DAA therapy — not an HBV trial
NCT02243280	Phase 2	Completed	174	SURVEYOR-I: G/P PK/efficacy in HCV GT1,4,5,6 — not an HBV trial
NCT02640482	Phase 3	Completed	304	ENDURANCE-2: placebo-controlled G/P trial in HCV GT2 — not an HBV trial

No trial in this evidence set enrolled patients for the purpose of treating or evaluating HBV infection.

Literature Evidence

PMID	Year	Type	Journal	Key Findings
29485084	2018	Review	Lancet Infect Dis	Discusses need for HBV vaccination after successful HCV treatment — a co-infection/prevention topic, not evidence of pibrentasvir activity against HBV
34092970	2021	Review	World J Gastroenterol	Overview of pediatric HBV/HCV management; notes current HBV therapies are not curative — contextual background only
41734217	2025	Retrospective	Klin Mikrobiol Infekc Lek	Retrospective review of antiviral treatment frequency/efficacy for chronic HBV and HCV in children — does not test pibrentasvir in HBV
40414600	2025	Cross-sectional	Annals of Hepatology	Compares HBV vs HCV drug pricing across countries — economic analysis, no efficacy data
31981264	2020	Cohort	J Viral Hepatitis	Real-world GLE/PIB effectiveness/safety in HCV patients with severe renal impairment (Taiwan) — HCV only
35431505	2022	Cohort	World J Gastroenterol	Real-world DAA effectiveness in HIV/HCV genotype 6 co-infection — HCV only
30982721	2019	Review	Lancet Gastroenterol Hepatol	HCV treatment in children/adolescents within global viral hepatitis elimination strategy — HCV-focused
35579223	2022	Review	Eur J Gen Pract	General overview of chronic HCV diagnosis and treatment — HCV only
34298832	2021	Review	Cancers	Hepatocellular carcinoma risk in chronic kidney disease — not specific to pibrentasvir or HBV
31114957	2019	Review	Clin Pharmacokinetics	PK/PD review of HCV DAA regimens including glecaprevir/pibrentasvir — HCV only

No publication in this set reports direct antiviral efficacy or clinical outcome data for pibrentasvir against HBV.

Norway Market Information

Pibrentasvir currently has no marketing authorization in Norway (0 licenses on file; market status: Not marketed). No product/authorization records are available to summarize.

Safety Considerations

Please refer to the package insert for safety information. (Key warnings, contraindications, and drug interaction data are not yet available in this evidence pack — retrieval of the TFDA/manufacturer label is flagged as a Blocking data gap.)

Conclusion and Next Steps

Decision: Hold

Rationale: Despite a high TxGNN similarity score, every clinical trial and nearly every publication supporting this "HBV" prediction is actually evidence for pibrentasvir's established HCV indication — none test HBV-specific antiviral activity. Pibrentasvir's mechanism (selective HCV NS5A inhibition) has no known counterpart target in HBV, and the same implausible pattern (HIV, hepatitis A/E, veterinary lentivirus infections, even an unrelated neurodevelopmental disorder) appears across this drug's entire top-10 prediction list, indicating a likely knowledge-graph clustering artifact rather than a genuine repurposing signal. Combined with the drug being unmarketed in Norway and a Blocking gap on core safety labeling, there is no basis to advance this candidate at this time.

To proceed, the following is needed:

Genuine in vitro/in vivo evidence of pibrentasvir antiviral activity against HBV (currently none exists)
TFDA/manufacturer package insert for warnings and contraindications (Blocking data gap)
Verified mechanism-of-action documentation from DrugBank (High-severity data gap)
A sanity check on TxGNN's disease-embedding neighborhood for this drug, given the pattern of implausible high-scoring predictions across the full candidate list
Disclaimer

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