Tenofovir in Asian Chronic Hepatitis B Patients

Serologic and Virologic Outcomes of Tenofovir in Asian Chronic Hepatitis B Patients With Prior Nucleoside Analogue Exposure

Tenofovir (TDF) has been demonstrated to have potency antiviral against the hepatitis B virus (HBV) in various multiple-centre trials, with no cases of resistance encountered. However, its efficacy and resistance profile in the Asian population, which constitute the majority of chronic hepatitis B (CHB) patients, is unknown. Compared to other nucleoside analogues, TDF has been associated with relatively high rates of hepatitis B surface antigen (HBsAg) seroclearance. It would be interested to see if this could be reproduced. The investigators plan to report the serologic and virologic results of our 140 nucleoside analogue-experienced patients who were commenced on TDF.

Study Overview

• Status: Completed
• Conditions: Chronic Hepatitis B
• Intervention / Treatment: Drug: Tenofovir disoproxil

Detailed Description

Recent multi-center trials have shown tenofovir disoprovil fumarate (TDF) demonstrating potent antiviral efficacy in both nucleoside-naive and -experienced chronic hepatitis B (CHB) patients. At present, there has been no identifiable amino acid substitutions associated with resistance to TDF.

Since TDF and adefovir (ADV), another licensed drug for CHB, belong to same molecular group, acyclic phosphonate, there had been various studies investigating the efficacy of TDF in ADV-resistant patients. The efficacy of tenofovir in this group of patients is conflicting. While several studies have shown TDF achieving similar viral suppression when compared to CHB patients without ADV-resistance , another study found that patients with the signature ADV mutations of rtA181V/T and /or rtN236T responded suboptimally to TDF. For all published studies, the number of patients with documented genotypic resistance to adefovir is actually small (n = 17-40), and therefore, further studies in this area are required.

Another interesting point to note was the relatively high rate of hepatitis B surface antigen (HBsAg) seroclearance found in patients taking TDF. The cumulative rate of HBsAg seroclearance up in hepatitis B e antigen (HBeAg)-positive was 10% after 4 years . However, the same study did not find any HBeAg-negative patients achieving HBsAg seroclearance. In addition, studies on TDF were mainly performed in Caucasian patients, the majority being genotypes A and D. A preliminary study performed in Asian patients, predominantly genotypes B and C, did not discover any cases of HBsAg seroclearance . Given the majority of the CHB population is found in Asia, further studies are needed to clarify if HBsAg seroclearance by nucleoside / nucleotide analogues is potentially achievable using TDF.

• Study Type: Interventional
• Enrollment (Actual): 141
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • Department of Medicine, the University of Hong Kong, Queen Mary Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. HBsAg-positivity for at least 6 months at presentation
2. Commenced on tenofovir for chronic hepatitis B
3. Exposure to other nucleoside analogues before starting TDF

Exclusion Criteria:

1. Concomitant liver diseases including chronic hepatitis C and/ or D infection, Wilson's disease, autoimmune hepatitis, primary biliary cirrhosis and primary sclerosing cholangitis.
2. Significant alcohol intake (> 20 grams per day)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Tenofovir disoproxil; Tenofovir disoproxil 300mg daily	Drug: Tenofovir disoproxil; Tenofovir disoproxil 300mg daily; Other Names: Viread

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Serum HBV DNA levels	3 Years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Resistance Profile	Performed using a Line Probe Assay (LiPA)	3 Years
HBsAg levels		3 years

Collaborators and Investigators

• Sponsor: The University of Hong Kong
• Collaborators: Gilead Sciences
• Investigators: Principal Investigator: Man-Fung Yuen, MD, The University of Hong Kong

Study record dates

Study Major Dates

• Study Start: April 1, 2008
• Primary Completion (Actual): November 1, 2012
• Study Completion (Actual): March 1, 2013

Study Registration Dates

• First Submitted: November 8, 2012
• First Submitted That Met QC Criteria: November 13, 2012
• First Posted (Estimate): November 20, 2012

Study Record Updates

• Last Update Posted (Estimate): December 30, 2014
• Last Update Submitted That Met QC Criteria: December 29, 2014
• Last Verified: December 1, 2014

More Information

Terms related to this study

• Keywords: Tenofovir; Resistance; HBV; HBsAg; HBV DNA
• Additional Relevant MeSH Terms: Digestive System Diseases; RNA Virus Infections; Virus Diseases; Infections; Blood-Borne Infections; Communicable Diseases; Liver Diseases; Hepatitis, Viral, Human; Hepadnaviridae Infections; DNA Virus Infections; Enterovirus Infections; Picornaviridae Infections; Hepatitis B; Hepatitis; Hepatitis A; Hepatitis B, Chronic; Hepatitis, Chronic; Molecular Mechanisms of Pharmacological Action; Anti-Infective Agents; Antiviral Agents; Reverse Transcriptase Inhibitors; Nucleic Acid Synthesis Inhibitors; Enzyme Inhibitors; Anti-HIV Agents; Anti-Retroviral Agents; Tenofovir
• Other Study ID Numbers: TDF-HKU; UW 11-241 (Other Identifier: Institutional Review Board The University of Hong Kong / Hospital Authority Hong Kong West Cluster)