Safety and Efficacy of Reduced Dose Efavirenz (EFV) With Standard Dose EFV Plus Two Nucleotide Reverse Transcriptase Inhibitors (N(t)RTI) in Antiretroviral-naïve HIV-infected Individuals. (encore1)
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ClinicalTrials.gov Identifier: NCT01011413 |
Recruitment Status
:
Completed
First Posted
: November 11, 2009
Last Update Posted
: December 19, 2014
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
HIV Infections | Drug: Efavirenz | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 630 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Treatment |
Official Title: | A Randomised, Double-blind, Placebo-controlled, Clinical Trial to Compare the Safety and Efficacy of Reduced Dose Efavirenz (EFV) With Standard Dose EFV Plus Two Nucleotide Reverse Transcriptase Inhibitors (N(t)RTI) in Antiretroviral-naïve HIV-infected Individuals Over 96 Weeks |
Study Start Date : | August 2011 |
Actual Primary Completion Date : | June 2013 |
Actual Study Completion Date : | August 2014 |

Arm | Intervention/treatment |
---|---|
Active Comparator: 600mg Efavirenz
Eligible patients will be centrally randomised to receive tenofovir (TDF) (300mg qd)/emtricitabine (FTC) (200mg qd) + EFV (600mg qd; 3 x 200mg qd)
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Drug: Efavirenz
3 x EFV 200mg tablets once daily
Other Name: Matrix EFV 200mg (Efamat 200) tablets
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Experimental: 400mg Efavirenz
Eligible patients will be centrally randomised to receive TDF (300mg qd)/FTC (200mg qd) + EFV (400mg qd; 2 x 200mg + 1 x 200mg placebo qd).
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Drug: Efavirenz
2 x EFV 200mg tablets plus 1x matched EFV placebo tablet once daily
Other Names:
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- The primary endpoint is the comparison between treatment groups of proportions of patients with HIV RNA <200 copies/mL 48 weeks after randomisation [ Time Frame: 1.5 years ]
- Virologic endpoints: proportion of patients with plasma HIV RNA <400 copies/mL and <50 copies/mL, and time to virological failure (HIV RNA ≥200 copies/ml) [ Time Frame: 2 years ]
- Immunologic endpoints: mean change from baseline in CD4+ T cell count/µL [ Time Frame: 2 years ]
- Clinical endpoints: rate of opportunistic disease or death, and rates of serious non-AIDS-defining illness and non-AIDS-related mortality [ Time Frame: 2 years ]
- Metabolic endpoints: mean/median change from baseline in fasted lipids (TC, LDL-c, HDL-c and TG), mean/median change from baseline in fasted glucose, and rates of initiation or changes in existing lipid-lowering therapies [ Time Frame: 2 years ]
- Adherence: median scores of self-reported adherence to randomised study medications [ Time Frame: 2 years ]
- Mean/median change from baseline in selected serum biochemical parameters [ Time Frame: 2 years ]
- Rates, types and severity of adverse events [ Time Frame: 2 years ]
- Steady state EFV concentrations [ Time Frame: 1 year ]Steady state EFV concentrations measured by plasma and dried blood spot samples

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Ages Eligible for Study: | 16 Years and older (Child, Adult, Senior) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- HIV-1 positive by licensed diagnostic test
- aged >16 years of age (or minimum age as determined by local regulations or as legal requirements dictate)
- 50 < CD4 <500 cells/µL
- No prior AIDS-defining illness, using the CDC 1993 case definition (except pulmonary tuberculosis)
- HIV RNA ≥1000 copies/mL
- no prior exposure to ART (including short course ARVs for preventing MTCT)
- calculated creatinine clearance (CLCr) more than or equal to 50 mL/min (Cockcroft-Gault formula)
- provision of written informed consent.
Exclusion Criteria:
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the following laboratory values:
- absolute neutrophil count (ANC) <500 cells/μL
- hemoglobin <7.0 g/dL
- platelet count <50,000 cells/μL
- AST and/or ALT >5 x ULN
- pregnant women or nursing mothers
- active opportunistic or malignant disease not under adequate control
- use of immunomodulators within 30 days prior to screening
- use of any prohibited medications
- current alcohol or illicit substance use that might adversely affect study participation

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01011413
Australia, New South Wales | |
St Vincent's Hospital | |
Sydney, New South Wales, Australia, 2010 |
Principal Investigator: | David Cooper, Professor | Kirby Institute |
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Kirby Institute |
ClinicalTrials.gov Identifier: | NCT01011413 History of Changes |
Other Study ID Numbers: |
NCHECR-ENCORE1 |
First Posted: | November 11, 2009 Key Record Dates |
Last Update Posted: | December 19, 2014 |
Last Verified: | November 2012 |
Keywords provided by Kirby Institute:
HIV ART Efavirenz Dose reduction |
Additional relevant MeSH terms:
HIV Infections Lentivirus Infections Retroviridae Infections RNA Virus Infections Virus Diseases Sexually Transmitted Diseases, Viral Sexually Transmitted Diseases Immunologic Deficiency Syndromes Immune System Diseases Efavirenz Reverse Transcriptase Inhibitors Nucleic Acid Synthesis Inhibitors |
Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Anti-Retroviral Agents Antiviral Agents Anti-Infective Agents Cytochrome P-450 CYP2C9 Inhibitors Cytochrome P-450 Enzyme Inhibitors Cytochrome P-450 CYP2C19 Inhibitors Cytochrome P-450 CYP2B6 Inducers Cytochrome P-450 Enzyme Inducers Cytochrome P-450 CYP3A Inducers |