Efficacy of Tenofovir Alafenamide Versus Placebo Added to a Failing Regimen Followed by Treatment With Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide Plus Atazanavir in HIV-1 Positive, Antiretroviral Treatment-Experienced Adults

Gilead Sciences

Status and phase: Completed; Phase 3

Conditions: HIV; HIV Infections; Acquired Immunodeficiency Syndrome

Treatments: Drug: ATV; Drug: E/C/F/TAF; Drug: TAF; Drug: Placebo; Drug: Current failing ARV regimen

Study type: Interventional

Funder types: Industry

Identifiers

NCT01967940

2013-002830-19 (EudraCT Number)

GS-US-292-0117

Details and patient eligibility

About

The primary objective of this study is to evaluate the efficacy of tenofovir alafenamide (TAF) versus placebo, each administered with the existing, failing antiretroviral (ARV) regimen. There are 2 parts to this study: Part 1 and Part 2.

Part 1 consists of 2 cohorts, starting with a sentinel cohort, in which participants will be enrolled to receive open-label TAF in addition to their current failing ARV regimen. This cohort will then be followed by a randomized, double-blind, cohort to compare the addition of TAF or placebo in HIV-1 positive adults who are failing their current ARV regimen.

In Part 2, all participants who complete Part 1 of the study will discontinue their failing ARV regimen and TAF or placebo for a 14-day washout period. Following the washout period, all participants who received TAF in Part 1 and have a > 0.5 log10 decline in HIV-1 RNA will receive elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide (E/C/F/TAF) single-tablet regimen (STR) plus atazanavir (ATV) once daily for 48 weeks. Participants who received TAF who have a ≤ 0.5 log10 decline in HIV-1 RNA will be discontinued from the study and will not be eligible to continue into Part 2 of the study. All participants who received placebo in Part 1 will be eligible to participate in Part 2 regardless of their viral load change. After completion of Part 2, all participants will be eligible to continue to receive E/C/F/TAF plus ATV in the extension phase until E/C/F/TAF becomes commercially available, or until Gilead Sciences terminates development of E/C/F/TAF in the applicable country.

Enrollment: 55 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Key Inclusion Criteria:

• Ability to understand and sign a written informed consent form, which must be obtained prior to initiation of study procedures

• Currently taking a failing ARV regimen

• Plasma HIV-1 RNA ≥ 500 copies/mL but ≤ 100,000 copies/mL at screening

• Normal ECG

• Estimated glomerular filtration rate (eGFR) ≥ 50 mL/min according to the Cockcroft-Gault formula for creatinine clearance

• Alanine aminotransferase (AST)/aspartate aminotransferase (AST) ≤ 5 × the upper limit of the normal range (ULN)

• Total bilirubin ≤ 1.5 mg/dL, or normal direct bilirubin

• Adequate hematologic function

• Serum amylase ≤ 5 × ULN

• Females may enter the study if it is confirmed that she is:

  • Not pregnant or nursing

  • Of non-childbearing potential (ie, have had a hysterectomy, both ovaries removed, medically documented ovarian failure, or are postmenopausal women > 54 years of age with cessation [for ≥ 12 months] of previously occurring menses), or

  • Of childbearing potential and agrees to utilize highly effective contraception methods or be non-heterosexually active or practice sexual abstinence from screening throughout the duration of study treatment and for 30 days following study drug dosing

    • Females who utilize hormonal contraceptive as one of their birth control methods must have used the same method for at least three months prior to study dosing.

• Males must agree to utilize a highly effective method of contraception during heterosexual intercourse or be non-heterosexually active, or practice sexual abstinence from first dose throughout the study period and for 30 days following the last study drug dose.

• Males must agree to refrain from sperm donation from first dose until at least 30 days after the last study drug dose.

Key Exclusion Criteria:

• A new AIDS-defining condition diagnosed within the 30 days prior to screening
• Hepatitis B surface antigen (HBsAg) positive
• Hepatitis C antibody positive (individuals with positive hepatitis C virus (HCV) antibody and without detectable HCV RNA are permitted to enroll)
• History of integrase inhibitor use
• Screening or historical genotype reports shows Q151M or T69ins or more than 3 TAMs.
• Screening or historical genotype report shows resistance to integrase inhibitors
• Individuals experiencing decompensated cirrhosis
• Current alcohol or substance use
• History of malignancy within the past 5 years (prior to screening) or ongoing malignancy other than cutaneous Kaposi's sarcoma (KS), basal cell carcinoma, or resected, non-invasive cutaneous squamous carcinoma. Individuals with cutaneous KS are eligible, but must not have received any systemic therapy for KS within 30 days of Part 1, Day 1 and must not be anticipated to require systemic therapy during the study.
• Active, serious infections (other than HIV-1 infection) requiring parenteral antibiotic or antifungal therapy within 30 days prior to Part 1, Day 1
• Any other clinical condition or prior therapy that would make the individual unsuitable for the study or unable to comply with dosing requirements
• Participation in any other clinical trial (including observational trials) without prior approval from the sponsor is prohibited while participating in this trial
• Receiving ongoing therapy with any disallowed medications, including any drugs not to be used with elvitegravir, cobicistat, emtricitabine and tenofovir alafenamide or known allergies to the excipients of E/C/F/TAF STR

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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55 participants in 4 patient groups, including a placebo group

Part 1 Sentinel Cohort (TAF)

Experimental group

Description:

TAF + their current failing ARV regimen for 10 days in Part 1

Treatment:

Drug: TAF

Drug: Current failing ARV regimen

Part 1 Randomized Cohort (TAF)

Experimental group

Description:

Following review of safety and efficacy data from the Sentinel Cohort, participants will be randomized to receive TAF + their current failing ARV regimen for 10 days in Part 1.

Treatment:

Drug: TAF

Drug: Current failing ARV regimen

Part 1 Randomized Cohort (Placebo)

Placebo Comparator group

Description:

Following review of safety and efficacy data from the Sentinel Cohort, participants will be randomized to receive placebo + their current failing ARV regimen for 10 days in Part 1.

Treatment:

Drug: Current failing ARV regimen

Drug: Placebo

Part 2 E/C/F/TAF+ATV

Experimental group

Description:

Following a 14-day period to confirm eligibility, participants in the Randomized Cohort TAF group with a \> 0.5 log10 decline in HIV-1 RNA and all participants completing the Randomized Cohort Placebo group will receive E/C/F/TAF+ATV for 48 weeks in Part 2. After completion of Part 2, all participants will be eligible to continue to receive E/C/F/TAF plus ATV in the extension phase until E/C/F/TAF becomes commercially available, or until Gilead Sciences terminates development of E/C/F/TAF in the applicable country.

Treatment:

Drug: E/C/F/TAF

Drug: ATV