Vicriviroc (SCH 417690) in Combination Treatment With Optimized ART Regimen in Experienced Participants (VICTOR-E1) (MK-7690-020/P03672) (VICTOR-E1)

Vicriviroc (SCH 417690) in Combination Treatment With Optimized ART Regimen in Experienced Participants (VICTOR-E1) (MK-7690-020/P03672)

Vicriviroc (SCH 417690) in Combination Treatment With Optimized ART Regimen in Experienced Subjects (VICTOR-E1)

Vicriviroc (vye-kri-VYE-rock) is an investigational drug that belongs to a new class of drugs, called C-C chemokine receptor type 5 (CCR5) receptor blockers. This group of drugs blocks one of the ways human immunodeficiency virus (HIV) enters T-cells (the cells that fight infection). The purpose of this 48-week study is to evaluate 2 dose levels of vicriviroc in participants with HIV who have not responded adequately to standard HIV treatments. This study was designed to evaluate the safety and efficacy of doses of vicriviroc, when taken in combination with other HIV drugs, in terms of ability to decrease the level of HIV (viral load) in the blood. The primary objective of the study was to evaluate antiviral efficacy of two doses of Vicriviroc maleate compared to placebo in combination with a protease inhibitor (PI)-containing optimized antiretroviral therapy (ART) regimen in CCR5-tropic HIV infected individuals failing a standard ART regimen.

This is a randomized, double-blind, placebo controlled, parallel-group, multi-center study of vicriviroc maleate in participants with HIV infected with CCR5-tropic virus only for whom standard antiretroviral treatment (ART) has failed. The study will evaluate the antiviral efficacy of two doses of vicriviroc (20 mg once daily (QD) and 30 mg QD) compared with placebo when added to optimized ART therapy. The optimized background regimen will be chosen by the investigator based on results of drug susceptibility tests, history of prior antiretroviral drug use by the participant, and drug toxicity. The background regimen must include at least 3 antiretroviral drugs (not including study drug), one of which must be a ritonavir-boosted protease inhibitor (≥100 mg ritonavir). There will be two interim analyses: when all participants have completed 12 weeks and 24 weeks of treatment, respectively. Based on the balance of safety and efficacy determined in these analyses, a dosage or dosages will be selected for further study in additional registrational trials. The primary efficacy analysis will be conducted when all participants have completed 48 weeks of treatment. After Week 48, participants who meet applicable criteria will be offered open label vicriviroc 30 mg QD, if appropriate, until the sponsor terminates the clinical development of vicriviroc. Additionally, participants who discontinue early from the study prior to Week 48 will be offered re-screening for the open label segment of the study.

Vicriviroc 30 mg once daily (QD), orally (PO), plus an open-label optimized antiretroviral therapy (ART) regimen containing a ritonavir-boosted protease inhibitor (PI/r) for 48 weeks.

Vicriviroc 30 mg once daily (QD), orally (PO), plus an open-label optimized ART regimen containing a ritonavir-boosted protease inhibitor (PI/r) for up to 45 months.

Three tablets of vicriviroc 10 mg once daily for 48 weeks (Double-blind Period) or for up to 45 months (Open Label Period).

An open-label ritonavir-boosted optimized background ART regimen containing ≥3 drugs (including a protease inhibitor [PI]) selected for each individual study participant by the investigator. The optimized regimens most commonly include new nucleoside analogs (NRTIs) and a PI, usually "boosted" with concomitant ritonavir.

Change From Baseline in Log10 Human Immunodeficiency Virus (HIV) Ribonucleic Acid (RNA) at Week 48 of the Double-blind Period

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 copies/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If the HIV RNA measurement was below the lower quantification of the UltraSensitive assay (LOQ of 50 copies/mL), a value of 49 was imputed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. If the participants had no subsequent following value or discontinued study treatment before the time point of interest, then the change from baseline was set to zero. Analysis was performed with a variance (ANOVA) model that adjusted for the treatment and stratification factors (intended enfuvirtide (T20) use in current newly-optimized background regimen (OBT) (Y/N) and HIV RNA at Screening (> or ≤100,000 copies/mL)).

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 copies/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If the HIV RNA measurement was below the lower quantification of the UltraSensitive assay (LOQ of 50 copies/mL), a value of 49 was imputed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. If the participants had no subsequent following value or discontinued study treatment before the time point of interest, then the change from baseline was set to zero.

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 copies/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. If the participants had no subsequent following value or discontinued study treatment before the time point of interest, then the change from baseline was set to zero.

Participants With a Time to Loss of Virologic Response (TLOVR) Based on 0.5 Log10 Reduction by 48 Weeks of the Double-blind Period

TLOVR defined as the time from randomization to either: 1. Failure to experience HIV RNA decline of ≥0.5 log10 from Baseline at Week 4, in which case time was set to 0; or 2. Rebound of HIV RNA to within 0.5 log10 of baseline value at any time after maximum suppression. HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 c/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If the HIV RNA measurement was below the lower quantification of the UltraSensitive assay (LOQ of 50 c/mL), a value of 49 was imputed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. If the participants had no subsequent following value or discontinued study treatment before the time point of interest, then the change from baseline was set to zero.

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 c/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If the HIV RNA measurement was below the lower quantification of the UltraSensitive assay (LOQ of 50 c/mL), a value of 49 was imputed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. Missing values of change from baseline were imputed by the average of immediately preceding and following non-missing values, and in any other cases, missing values were imputed by zero.

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 c/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If the HIV RNA measurement was below the lower quantification of the UltraSensitive assay (LOQ of 50 c/mL), a value of 49 was imputed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. Missing values of change from baseline were imputed by the average of immediately preceding and following non-missing values, and in any other cases, missing values were imputed by zero.

Blood was collected and CD4+ cell count assessment was done by flow cytometry. Mean change from baseline in CD4 cell counts was determined. Any missing value was replaced by carrying forward baseline except if the immediately preceding and following value are available, in which case the arithmetic average of the two was used. If more than 1 CD4 count was available during a visit window, the value that was the closest to the time point of interest was used. If more than 1 pre-treatment CD4 value was available at baseline, the arithmetic mean of the 2 CD4 counts was taken.

Blood was collected and CD4+ cell count assessment was done by flow cytometry. Mean change from baseline in CD4 cell counts was determined. Any missing value was replaced by carrying forward baseline except if the immediately preceding and following value are available, in which case the arithmetic average of the two was used. If more than 1 CD4 count was available during a visit window, the value that was the closest to the time point of interest was used. If more than 1 pre-treatment CD4 value was available at baseline, the arithmetic mean of the 2 CD4 counts was taken.

Blood was collected and CD4+ cell count assessment was done by flow cytometry. Mean change from baseline in CD4 cell counts was determined. Any missing value was replaced by carrying forward baseline except if the immediately preceding and following value are available, in which case the arithmetic average of the two was used. If more than 1 CD4 count was available during a visit window, the value that was the closest to the time point of interest was used. If more than 1 pre-treatment CD4 value was available at baseline, the arithmetic mean of the 2 CD4 counts was taken.

Blood was collected and CD4+ cell count assessment was done by flow cytometry. Mean change from baseline in CD4 cell counts was determined. Any missing value was replaced by carrying forward baseline except if the immediately preceding and following value are available, in which case the arithmetic average of the two was used. If more than 1 CD4 count was available during a visit window, the value that was the closest to the time point of interest was used. If more than 1 pre-treatment CD4 value was available at baseline, the arithmetic mean of the 2 CD4 counts was taken. After completion of the Double-Blind Period, eligible participants could enroll in the Open Label Period and continue treatment.

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 copies/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. If the participants had no subsequent following value or discontinued study treatment before the time point of interest, then the change from baseline was set to zero. HIV RNA <400 copies/mL is a less stringent measure of viral suppression and indicates that a participant responded to treatment.

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay. For participants who had HIV RNA below the lower quantification of the Standard assay (LOQ of 400 copies/mL), the AMPLICOR HIV-1.5 UltraSensitive assay was performed. If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. If the participants had no subsequent following value or discontinued study treatment before the time point of interest, then the change from baseline was set to zero. HIV RNA <400 copies/mL is a less stringent measure of viral suppression and indicates that a participant responded to treatment.

HIV RNA was measured by AMPLICOR HIV-1 MONITOR Standard assay (the lower quantification, [LOQ of 400 copies/mL]) and for HIV RNA below the LOQ, with the AMPLICOR HIV-1.5 UltraSensitive assay. HIV RNA <400 copies/mL is a less stringent measure of viral suppression (participant responded to treatment). HIV RNA < 50 copies/mL is a very stringent measure of viral suppression (participant achieved full virologic suppression). If a continuing participant has a missing HIV RNA value at the time point of interest, the geometric mean of immediately preceding and following values was used. Missing value for any reason will be imputed as non-responder except if the immediately preceding and following viral counts are both <50 copies/mL. Results are shown for Group 1. for participants with baseline HIV RNA <50 copies/mL, Group 2. baseline HIV RNA 50 to <400 copies/mL, and Group 3. baseline HIV RNA>400 copies/mL.

The lower limit of HIV RNA <50 copies/mL was determined by the UltraSensitive assay. HIV RNA <50 copies/mL is a very stringent measure of viral suppression and indicates that a participant achieved full virologic suppression. Missing value for any reason were imputed as non-responder except if the immediately preceding and following viral counts are both <50 copies/mL.

The lower limit of HIV RNA <50 copies/mL was determined by the UltraSensitive assay. HIV RNA < 50 copies/mL is a very stringent measure of viral suppression and indicates that a participant achieved full virologic suppression. Missing value for any reason will be imputed as non-responder except if the immediately preceding and following viral counts are both <50 copies/mL.

The lower limit of HIV RNA <50 copies/mL was determined by the UltraSensitive assay. HIV RNA <50 copies/mL is a very stringent measure of viral suppression and indicates that a participant achieved full virologic suppression. Missing value for any reason were imputed as non-responder except if the immediately preceding and following viral counts are both <50 copies/mL.

Participants With Acquired Immunodeficiency Syndrome (AIDS)-Defining Events of the Double-blind Period

All potential AIDS-defining events (ADEs) identified by investigators and the sponsor were submitted with supporting clinical data to an Adjudication Committee of HIV experts. These experts did not participant in the study and reviewed the data without knowledge of treatment assignment. To be analyzed as an ADE, the event required concurrence on the diagnosis by at least two of the three Adjudication Committee members. Their review consisted of available clinical and laboratory data, including relevant radiologic, endoscopic, and pathology assessments, when applicable as well as autopsy reports and/or hospital admission and discharge summaries. An independent radiologist was called upon when necessary. Guidelines for Diagnosis of AIDS-Defining Conditions (CDC's 1993 Revised Classification System for HIV Infection and Expanded Surveillance Case Definition for AIDS Among Adolescents and Adults) was used.

All potential AIDS-defining events (ADEs) identified by investigators and the sponsor were submitted with supporting clinical data to an Adjudication Committee of HIV experts, who did not participant in the study and reviewed the blinded data. Their review consisted of available clinical and laboratory data, including relevant radiologic, endoscopic, and pathology assessments, autopsy reports and/or hospital admission and discharge summaries. An independent radiologist was called upon when necessary. Guidelines for Diagnosis of AIDS-Defining Conditions (CDC's 1993 Revised Classification System for HIV Infection and Expanded Surveillance Case Definition for AIDS Among Adolescents and Adults) was used. To be analyzed as an ADE, the event required concurrence on the diagnosis by at least 2 of 3 Adjudication Committee members. After completion of the Double-blind Period, eligible participants could enroll in the Open Label Period and continue treatment.

All potential AIDS-defining events (ADEs) identified by investigators and the sponsor were submitted with supporting clinical data to an independent and blinded Adjudication Committee of HIV experts. To be analyzed as an ADE, the event required concurrence on the diagnosis by at least 2 of the 3 Adjudication Committee members. Their review included available clinical and laboratory data, including relevant radiologic, endoscopic, and pathology assessments, when applicable as well as autopsy reports and/or hospital admission and discharge summaries. An independent radiologist was called upon when necessary. Guidelines for Diagnosis of AIDS-Defining Conditions (CDC's 1993 Revised Classification System for HIV Infection and Expanded Surveillance Case Definition for AIDS Among Adolescents and Adults) was used.

Key pharmacokinetic (PK) parameters (maximum plasma concentration [Cmax], minimum plasma concentration [Cmin], area under the plasma concentration-time curve [AUC]) were estimated using a population PK modeling approach based on a two-compartment model with first-order absorption and elimination. Cmin is a measure of the minimum amount of drug in the plasma after the dose is given. Pharmacokinetics studies were not performed with participants receiving Placebo.

Key pharmacokinetic (PK) parameters (maximum plasma concentration [Cmax], minimum plasma concentration [Cmin], area under the plasma concentration-time curve [AUC]) were estimated using a population PK modeling approach based on a two-compartment model with first-order absorption and elimination. Cmax is a measure of the maximum amount of drug in the plasma after the dose is given. Pharmacokinetics studies were not performed with participants receiving Placebo.

Key pharmacokinetic (PK) parameters (maximum plasma concentration [Cmax], minimum plasma concentration [Cmin], area under the plasma concentration-time curve [AUC]) were estimated using a population PK modeling approach based on a two-compartment model with first-order absorption and elimination. AUC is a measure of the mean concentration levels of drug in the plasma after the dose. Pharmacokinetics studies were not performed with participants receiving Placebo.

Resistance testing was performed at Baseline and again at the time of virologic failure or study discontinuation using the Phenosense GT assay (Monogram Biosciences, South San Francisco, CA). This assay used a combination of genotypic and phenotypic resistance techniques to determine an overall sensitivity score (OSS). The OSS represents the total number of drugs in the optimized background regimen (OBT) to which the virus was fully susceptible. Partial sensitivity is not counted towards the OSS. VCV susceptibility testing was performed with a maximal percent inhibition (MPI) plateau value of <85% as a cutoff for resistance.

Participants With Detectable C-X-C Chemokine Receptor Type 4 (CXCR4)-Tropic Virus of the Double-blind Period

Viral tropism was determined using the Monogram Trofile assay and antiviral drug susceptibility was measured by Monogram PhenoSense GT assay, based on both genotypic and phenotypic sensitivity of HIV isolates. The lower limit of sensitivity of the Trofile assay employed in this study for detection of minor X-4 using variants was 5-10%.

Participants With Detectable CXCR4-Tropic Virus and Immune Decline (≥50% Fall in CD4 Count From Baseline) of the Double-blind Period

Viral tropism was determined using the Monogram Trofile assay and antiviral drug susceptibility was measured by Monogram PhenoSense GT assay, based on both genotypic and phenotypic sensitivity of HIV isolates. The lower limit of sensitivity of the Trofile assay employed in this study for detection of minor X-4 using variants was 5-10%. Participants with emergence of CXCR4 tropism who had a concomitant decline in CD4 count by ≥50% below baseline was also computed.

Inclusion Criteria: Adult participants with documented HIV infection with no detectable C-X-C Motif Chemokine Receptor 4 (CXCR4) Prior therapy for ≥3 months with ≥3 classes of currently marketed (US FDA-approved) antiretroviral agents (nucleoside reverse transcriptase inhibitor, NRTIs, non-nucleoside reverse transcriptase inhibitor (NNRTIs), protease inhibitor (PIs), or fusion inhibitors) at any time prior to screening HIV ribonucleic acid (RNA) ≥1000 copies/mL on a stable ART regimen for ≥6 weeks prior to Screening and ≥8 weeks prior to randomization ≥1 genotypically documented resistance mutation to a reverse transcriptase (RT) inhibitor and ≥1 primary resistance mutation to a PI Acceptable hematologic, renal and hepatic laboratory parameters Exclusion Criteria: No history of previous malignancy (with the exceptions of cutaneous Kaposi's Sarcoma without visceral or mucosal involvement that resolved with highly active antiretroviral therapy (HAART) but without systemic anti-cancer treatment, and basal-cell carcinoma of skin surgically resected with disease-free margins on pathology exam) Treatment with cytotoxic cancer chemotherapy, Recurrent seizure, or central nervous system (CNS) condition or drug use predisposing to seizure in the opinion of the investigator No active acquired immunodeficiency syndrome (AIDS)-defining opportunistic infection

Suleiman J, Zingman BS, Diaz RS, Madruga JV, DeJesus E, Slim J, Mak C, Lee E, McCarthy MC, Dunkle LM, Walmsley S. Vicriviroc in combination therapy with an optimized regimen for treatment-experienced subjects: 48-week results of the VICTOR-E1 phase 2 trial. J Infect Dis. 2010 Feb 15;201(4):590-9. doi: 10.1086/650342.