Daclatasvir

證據等級: L5

預測適應症: 10 個

Daclatasvir: From Hepatitis C to Hepatitis B Virus Infection

One-Sentence Summary

Daclatasvir is a potent, pangenotypic NS5A replication complex inhibitor originally approved internationally for the treatment of chronic hepatitis C virus (HCV) infection, with no current registration in India. The TxGNN model predicts it may be effective for Hepatitis B Virus (HBV) Infection, with 1 directly relevant completed Phase 2/3 clinical trial and 19 publications currently supporting investigation into this direction. However, the mechanistic link between an NS5A inhibitor and HBV — a DNA virus with no NS5A homologue — is fundamentally weak, and existing clinical evidence primarily reflects HBV reactivation monitoring during HCV treatment rather than direct anti-HBV therapeutic activity.

Quick Overview

Item	Content
Original Indication	Chronic hepatitis C virus (HCV) infection (international approval; no India registration)
Predicted New Indication	Hepatitis B Virus (HBV) Infection
TxGNN Prediction Score	99.80%
Evidence Level	L3
India Market Status	Not marketed
Number of Registrations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data is not available in this evidence pack. Based on known published information, daclatasvir is an HCV NS5A replication complex inhibitor. NS5A is a multifunctional phosphoprotein essential for HCV RNA replication, virion assembly, and release. By disrupting NS5A, daclatasvir has demonstrated exceptionally high sustained virologic response (SVR) rates in HCV infection — including genotypes 1 through 6 — when used in combination with sofosbuvir or other direct-acting antivirals.

Both HCV and HBV are hepatotropic viruses sharing a common clinical trajectory: chronic infection → liver fibrosis → cirrhosis → hepatocellular carcinoma (HCC). This phenotypic and epidemiological overlap creates a strong topological connection in the TxGNN knowledge graph, likely explaining the high prediction score. Furthermore, HCV/HBV co-infection is clinically common — particularly in Egypt, Southeast Asia, and sub-Saharan Africa — meaning daclatasvir-containing regimens have been studied in many patients who simultaneously carry HBV, contributing real-world exposure data.

However, the mechanistic connection is weak at its core. HBV belongs to the Hepadnaviridae family and is a partially double-stranded DNA virus that replicates via an RNA intermediate through reverse transcription. It has no NS5A protein or functional homologue. Critically, multiple case reports document HBV reactivation — not improvement — during DAA-based HCV therapy (PMID 27329484, 26297529), because successful HCV clearance removes HCV’s immunological suppression of HBV replication. This is a safety warning rather than a therapeutic signal. The TxGNN score of 99.80% very likely reflects graph-level proximity of “viral hepatitis” nodes rather than a direct pharmacological rationale.

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT02555943	Phase 2/3	Completed	23	The most directly relevant trial: a prospective study of DAA therapy specifically in HCV/HBV co-infected patients, assessing incidence, morbidity, mortality and risk factors for HBV reactivation during HCV treatment — however, HBV reactivation monitoring, not HBV cure, was the primary endpoint
NCT01016912	Phase 2	Completed	51	Daclatasvir + PegIFN-alfa-2b + ribavirin in Japanese HCV genotype 1 patients; HBV evaluated as a comorbidity screening item during patient selection, not treated as a primary endpoint
NCT02304159	Phase 4	Completed	39	Randomized study comparing 16 vs. 24 weeks of DCV + SOF + RBV in cirrhotic HCV genotype 3 patients; HBV management noted as a secondary safety consideration
NCT02640157	Phase 3	Completed	506	Head-to-head comparison of ABT-493/ABT-530 versus SOF + daclatasvir in HCV genotype 3; no direct HBV treatment objective
NCT03226717	N/A	Unknown	100	Study of DAA effects on HCV-related arthropathy in Egypt; HBV not a treatment target

Literature Evidence

PMID	Year	Type	Journal	Key Findings
31722032	2020	Real-world Cohort	Trans R Soc Trop Med Hyg	SOF/DCV-based therapy in Egyptian patients with chronic HCV and HCV/HBV co-infection; demonstrated high SVR rates for HCV; HBV viral load monitored but was not a primary treatment target
29194858	2018	Cohort	J Viral Hepat	Low incidence of HBV reactivation during interferon-free DAA therapy across 790 patients; among those receiving asunaprevir + daclatasvir, reactivation rates were modest and manageable with prophylaxis
28555436	2017	Cohort	Indian J Gastroenterol	HBV infection associated with 43% HCC recurrence rate in HCV patients who achieved HCV SVR via DAA therapy; HBV as a co-risk factor, not a DAA treatment target
27329484	2016	Case Report	Clin J Gastroenterol	Acute hepatitis B in an HCV-infected patient following daclatasvir + asunaprevir therapy; HBV reactivation documented as an adverse safety event, not a therapeutic benefit
26297529	2016	Case Report	Hepatol Res	HBV reactivation in an HBV/HCV co-infected patient during interferon-free DCV + asunaprevir DAA therapy; underscores the critical need for HBV monitoring when using HCV DAAs in co-infected patients
36838792	2023	Computational	Molecules	Virtual screening of HBV pre-genomic RNA (pgRNA) ε stem-loop as a novel antiviral target; provides in silico rationale for exploring new chemical scaffolds against HBV replication — indirect mechanistic support for exploring HBV-specific drug development
30369001	2019	Cohort	Transplant Infect Dis	Efficacy and safety of SOF + DCV in kidney transplant recipients with chronic HCV; HBV co-infection managed as a comorbidity requiring separate treatment
26904396	2016	Review	Acta Pharm Sin B	Comprehensive review of direct anti-HCV agents; explicitly notes that HCV — unlike HBV and HIV — is a curable disease, underscoring the fundamental mechanistic gap between NS5A inhibitors and HBV therapies
35248212	2022	Cohort	Lancet Gastroenterol Hepatol	SOF-VEL-VOX re-treatment in Rwanda for HCV patients with prior DAA failure; contextualises HBV/HCV co-infection burden in low-income settings where daclatasvir is most accessible
40578045	2025	Observational	Int J Drug Policy	Decentralized point-of-service model integrating HBV, HCV, and HIV prevention in people who inject drugs in South Africa; illustrates the real-world epidemiological overlap requiring coordinated management of these co-infections

India Market Information

Daclatasvir (DrugBank ID: DB09102) currently has no registered products in India. It has not received CDSCO approval and is not commercially available through domestic market channels. The drug is approved in other jurisdictions — including as Daklinza® in the EU, USA, and Japan — exclusively for the treatment of chronic HCV infection, typically in combination with sofosbuvir.

Safety Considerations

Drug Interactions (89 interactions documented; key interactions shown below):

Interacting Drug	Severity	Category
Dexamethasone	Major	Corticosteroid; CYP3A4 inducer — may significantly reduce daclatasvir exposure
Clarithromycin	Major	Strong CYP3A4 inhibitor — may substantially increase daclatasvir plasma levels
Eluxadoline	Major	Gastrointestinal agent; co-administration not recommended
Cobicistat	Major	CYP3A4 inhibitor used in HIV regimens — requires daclatasvir dose reduction to 30 mg QD
Rosuvastatin	Moderate	Statin; increased plasma exposure risk — monitor for myopathy
Simvastatin	Moderate	Statin; elevated exposure risk — consider dose reduction
Metformin	Moderate	Antidiabetic; potential interaction via organic cation transporter (OCT) pathways
Apixaban	Moderate	Direct oral anticoagulant — monitor anticoagulation parameters
Rifaximin	Moderate	Non-absorbed antibiotic; potential PK interaction
Aprepitant	Moderate	NK1 antagonist / CYP3A4 modulator — may alter daclatasvir exposure

Detailed prescribing warnings and contraindications specific to Indian regulatory labelling are not currently available. Please refer to the EMA or FDA-approved package insert for comprehensive safety guidance.

Conclusion and Next Steps

Decision: Hold

Rationale: Daclatasvir’s NS5A inhibition mechanism has no known direct pharmacological activity against HBV — a DNA virus with fundamentally different replication machinery — and the only clinically relevant trial in HCV/HBV co-infection (NCT02555943, n=23) was designed to detect HBV reactivation risk, not to treat HBV. Published case reports document HBV reactivation as a safety concern during daclatasvir therapy, making a therapeutic benefit claim unjustifiable without dedicated in vitro and in vivo anti-HBV efficacy data.

To proceed, the following is needed:

MOA clarification (DG002): Obtain full DrugBank pharmacology data confirming whether any known off-target activity could plausibly affect HBV replication
Regulatory safety data (DG001): Download and parse the CDSCO/FDA prescribing information to complete the S1 safety screening gate
In vitro HBV activity data: Commission a cell-based HBV replication assay (e.g., HepAD38 or HepG2.2.15) to determine whether daclatasvir has any measurable anti-HBV effect at clinically achievable concentrations
Mechanistic hypothesis revision: If pursuing the co-infection angle, reframe the hypothesis around optimised HCV/HBV co-infection management protocols rather than direct HBV antiviral activity
Dedicated Phase 2 RCT design: If in vitro data proves positive, design a small proof-of-concept trial in HCV/HBV co-infected patients with explicit dual HBV and HCV virological endpoints
Disclaimer

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