Phase 3 Study of the Safety and Efficacy of Ritonavir-Boosted Elvitegravir (EVG/r) Versus Raltegravir (RAL)
The purpose of this study is to compare the safety, tolerability and efficacy of a regimen containing once-daily ritonavir-boosted elvitegravir or twice-daily raltegravir added to a background regimen in HIV-1 infected, antiretroviral treatment-experienced adults who have documented resistance, or at least six months experience prior to screening with two or more different classes of antiretroviral agents.
|Study Design:||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Single Group Assignment
Masking: Double Blind (Subject, Caregiver, Investigator)
Primary Purpose: Treatment
|Official Title:||A Multicenter, Randomized, Double-Blind, Double-Dummy, Phase 3 Study of the Safety and Efficacy of Ritonavir-Boosted Elvitegravir (EVG/r) Versus Raltegravir (RAL) Each Administered With a Background Regimen in HIV-1 Infected, Antiretroviral Treatment-Experienced Adults|
- The primary efficacy endpoint is the proportion of subjects achieving and maintaining confirmed HIV-1 RNA less than 50 copies/mL through Week 48. [ Time Frame: 48 weeks ] [ Designated as safety issue: No ]
- To evaluate the efficacy, safety and tolerability of the two treatment arms through 48 weeks of treatment. [ Time Frame: 48 weeks ] [ Designated as safety issue: No ]
|Study Start Date:||June 2008|
Ritonavir-boosted elvitegravir 150 mg QD (ritonavir-boosted elvitegravir 85 mg QD for subjects taking atazanavir/r or lopinavir/r as part of their BR) + BR (N = 350)
Elvitegravir 85 mg, 150 mg or matching placebo administered orally QD (with ritonavir-boosted PI) to be taken with food
Active Comparator: 2
Raltegravir 400 mg BID + BR (N = 350)
Raltegravir 400 mg tablets or matching placebo administered orally BID and to be taken according to the prescribing information.
Other Name: Isentress
This is a double-blind, double-dummy, multicenter, randomized, active-controlled study to assess the safety and efficacy of a regimen containing ritonavir-boosted elvitegravir versus raltegravir, each administered with a background regimen (BR) containing a fully-active ritonavir-boosted protease inhibitor (PI) and a second single agent in HIV-1 infected, antiretroviral treatment-experienced adults. Subjects will be randomized in a 1:1 ratio to one of the following two treatment arms:
- Treatment Arm 1: Ritonavir-boosted elvitegravir 150 mg QD (ritonavir-boosted elvitegravir 85 mg QD for subjects taking atazanavir/r or lopinavir/r as part of their BR) + BR (N = 350)
- Treatment Arm 2: Raltegravir 400 mg BID + BR (N = 350)
Due to known pharmacokinetic interactions, subjects who are taking atazanavir/r (ATV/r) or lopinavir/r (LPV/r) as part of their BR will receive elvitegravir 85 mg if randomized to Treatment Arm 1.
The BR shall be constructed by the investigator based on viral resistance testing and shall be composed of a fully-active ritonavir-boosted PI and a second single agent.
The fully-active PI is defined by phenotypic resistance analysis. For phenotypic susceptibility, fully active is defined as being below the lower clinical or biological cutoff. The following ritonavir-boosted PIs are allowed to be prescribed by the investigator as part of the BR: atazanavir/r, darunavir/r, fosamprenavir/r, lopinavir/r, or tipranavir/r. Subjects must take their ritonavir dose based on the dosing schedule indicated in the prescribing information for the PI; no additional ritonavir is required to be taken with elvitegravir. No other marketed PIs will be allowed as part of the BR due to unknown pharmacokinetic interactions.
The second single agent may or may not be fully-active and can be one nucleoside or nucleotide reverse transcriptase inhibitor (NRTI), etravirine, maraviroc, or T-20. However, the second single agent must not include an integrase inhibitor; the non-nucleoside reverse transcriptase inhibitors (NNRTI) efavirenz, nevirapine, or delavirdine (due to unknown pharmacokinetic interactions); or fixed-dose combination antiretroviral therapies.
Two identical Phase 3 studies of elvitegravir tablets boosted with ritonavir are currently ongoing in treatment-experienced adults with HIV-1 infection. Initiated in July 2008, Study GS-US-183-0144 (planned N=700) is being conducted in the US and Puerto Rico and Study GS-US-183-0145 (planned N=700) is being conducted in Europe, Australia, Mexico and Canada. Given the declining numbers of patients with unsuppressed viremia, Gilead is combining the two ongoing studies into a single, global Phase 3 study (GS-US-183-0145) to enroll a total of 700 subjects. The protocol amendment enables the transfer of subjects from Study GS-US-183-0144 into study GS-US-183-0145.