Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12606000283572
Ethics application status
Approved
Date submitted
20/06/2006
Date registered
5/07/2006
Date last updated
5/07/2006
Type of registration
Retrospectively registered

Titles & IDs
Public title
The Extension Study
Scientific title
A phase 4, open-label, multi-centre, observational extension study monitoring the long-term safety and efficacy of adefovir dipivoxil 10mg daily in treatment experienced patients with chronic hepatitis B.
Secondary ID [1] 274 0
IN-AU-103-0163
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Chronic Hepatitis B Virus Infection 1258 0
Condition category
Condition code
Inflammatory and Immune System 1344 1344 0 0
Liver

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
adefovir dipivoxil 10mg tablets daily. Patients have been receiving adefovir dipivoxil for approx. 5 years prior to study entry and will be receiving adefovir post completion if appropriate. The follow-up period for the extension study will also be 5 years.
Intervention code [1] 1152 0
Treatment: Drugs
Comparator / control treatment
No comparator.
Control group
Uncontrolled

Outcomes
Primary outcome [1] 1832 0
Proportion of Treatment Failures, defined as:
• Virologic failure, defined as increase in Hepatitis B Virus Deoxyribonucleid Acid (HBV DNA) by = 1 log10 copies/ml detected on two consecutive, separate occasions
Timepoint [1] 1832 0
Followed-up every 3 months, for the period of 5 years.
Primary outcome [2] 1833 0
Proportion of Treatment Failures, defined as:
• Development of genotypic resistance, defined as detection of mutations associated with adefovir resistance (N236T; A181V)
Timepoint [2] 1833 0
Followed-up every 3 months, for the period of 5 years.
Primary outcome [3] 1834 0
Proportion of Treatment Failures, defined as:
• Clinical resistance, defined as continuous alanine aminotransferase (ALT) elevation (> 2 x upper limit of normal [ULN]) measured at two consecutive, separate occasions.
Timepoint [3] 1834 0
Followed-up every 3 months, for the period of 5 years.
Secondary outcome [1] 3208 0
ALT normalisation and mean change from baseline
Timepoint [1] 3208 0
Measured every 3 months.
Secondary outcome [2] 3209 0
Proportion of patients with serum HBV DNA at or below the assay lower limit of quantification
Timepoint [2] 3209 0
Measured every 3 months.
Secondary outcome [3] 3210 0
Incidence of drug resistant mutations
Timepoint [3] 3210 0
Measured every 3 months.
Secondary outcome [4] 3211 0
Proportion of patients with HBsAg/HBeAg loss and seroconversion
Timepoint [4] 3211 0
Measured every 3 months.
Secondary outcome [5] 3212 0
Mean change in HBV DNA from baseline
Timepoint [5] 3212 0
Measured every 3 months.
Secondary outcome [6] 3213 0
Liver histology (if performed)
Timepoint [6] 3213 0
Measured at the end of the study (5 years).

Eligibility
Key inclusion criteria
Comment: Since this study is an extension study to studies 437/438/480, minimal inclusion/exclusion criteria apply. (The original study included both male and female participants over the age of 18 years). Inclusion:• Participation in and completion of study GS-98-437, GS-98-438 or GS-00-480.• Currently treated with adefovir dipivoxil 10mg once a day.
Minimum age
18 Years
Maximum age
Not stated
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Pregnant or breastfeeding females• Known hypersensitivity to adefovir, adefovir dipivoxil, or any of the excipients in adefovir dipivoxil tablets.

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Phase 4
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
1/07/2006
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
28
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 1471 0
Commercial sector/Industry
Name [1] 1471 0
Gilead Sciences
Country [1] 1471 0
Primary sponsor type
Individual
Name
Prof. Meng Ngu, Concord Hospital
Address
Country
Australia
Secondary sponsor category [1] 1298 0
Commercial sector/Industry
Name [1] 1298 0
Gilead Sciences Pty Ltd
Address [1] 1298 0
Country [1] 1298 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 2853 0
Concord Hospital, human research ethics committee
Ethics committee address [1] 2853 0
Ethics committee country [1] 2853 0
Australia
Date submitted for ethics approval [1] 2853 0
Approval date [1] 2853 0
09/06/2006
Ethics approval number [1] 2853 0
CH62/6/2006-029-M Ngu

Summary
Brief summary
Adefovir dipivoxil 10mg tablets were approved for the treatment of chronic hepatitis B by the TGA in 2003 and are now marketed as Hepsera(r) by Gilead Sciences. Patients who are not resistant to another anti-hepatitis B virus drug called lamivudine are not able to access Hepsera at a PBS reimbursed price.

Patients who participated in the adefovir dipivoxil clinical trials GS-98-437, GS-98-438, and GS-00-480 and are still taking adefovir dipivoxil have never received lamivudine and thus cannot receive Hepsera at reduced price. This study will allow the patients to continue accessing adefovir free of charge and provide unprecedented data on the long-term safety and efficacy of adefovir dipivoxil without changing the procedures and tests routinely done during normal visits to the clinic.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 35127 0
Address 35127 0
Country 35127 0
Phone 35127 0
Fax 35127 0
Email 35127 0
Contact person for public queries
Name 10341 0
Ms Vivienne Schiavone
Address 10341 0
Department of Gastroenterology
Concord Hospital
Hospital Rd
Concord West NSW 2139
Country 10341 0
Australia
Phone 10341 0
+61 2 97675563
Fax 10341 0
Email 10341 0
[email protected]
Contact person for scientific queries
Name 1269 0
Professor Meng Ngu
Address 1269 0
Department of Gastroenterology
Concord Hospital
Hospital Rd
Concord West NSW 2139
Country 1269 0
Australia
Phone 1269 0
+61 2 97675563
Fax 1269 0
Email 1269 0
[email protected]

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.