Efficacy of a tetravalent dengue vaccine in children in Latin America.

BACKGROUND: In light of the increasing rate of dengue infections throughout the world despite vector-control measures, several dengue vaccine candidates are in development. METHODS: In a phase 3 efficacy trial of a tetravalent dengue vaccine in five Latin American countries where dengue is endemic, we randomly assigned healthy children between the ages of 9 and 16 years in a 2:1 ratio to receive three injections of recombinant, live, attenuated, tetravalent dengue vaccine (CYD-TDV) or placebo at months 0, 6, and 12 under blinded conditions. The children were then followed for 25 months. The primary outcome was vaccine efficacy against symptomatic, virologically confirmed dengue (VCD), regardless of disease severity or serotype, occurring more than 28 days after the third injection. RESULTS: A total of 20,869 healthy children received either vaccine or placebo. At baseline, 79.4% of an immunogenicity subgroup of 1944 children had seropositive status for one or more dengue serotypes. In the per-protocol population, there were 176 VCD cases (with 11,793 person-years at risk) in the vaccine group and 221 VCD cases (with 5809 person-years at risk) in the control group, for a vaccine efficacy of 60.8% (95% confidence interval [CI], 52.0 to 68.0). In the intention-to-treat population (those who received at least one injection), vaccine efficacy was 64.7% (95% CI, 58.7 to 69.8). Serotype-specific vaccine efficacy was 50.3% for serotype 1, 42.3% for serotype 2, 74.0% for serotype 3, and 77.7% for serotype 4. Among the severe VCD cases, 1 of 12 was in the vaccine group, for an intention-to-treat vaccine efficacy of 95.5%. Vaccine efficacy against hospitalization for dengue was 80.3%. The safety profile for the CYD-TDV vaccine was similar to that for placebo, with no marked difference in rates of adverse events. CONCLUSIONS: The CYD-TDV dengue vaccine was efficacious against VCD and severe VCD and led to fewer hospitalizations for VCD in five Latin American countries where dengue is endemic. (Funded by Sanofi Pasteur; ClinicalTrials.gov number, NCT01374516.).

Ledipasvir and Sofosbuvir for HCV in Patients Coinfected with HIV-1.

BACKGROUND: Effective treatment for hepatitis C virus (HCV) in patients coinfected with human immunodeficiency virus type 1 (HIV-1) remains an unmet medical need. METHODS: We conducted a multicenter, single-group, open-label study involving patients coinfected with HIV-1 and genotype 1 or 4 HCV receiving an antiretroviral regimen of tenofovir and emtricitabine with efavirenz, rilpivirine, or raltegravir. All patients received ledipasvir, an NS5A inhibitor, and sofosbuvir, a nucleotide polymerase inhibitor, as a single fixed-dose combination for 12 weeks. The primary end point was a sustained virologic response at 12 weeks after the end of therapy. RESULTS: Of the 335 patients enrolled, 34% were black, 55% had been previously treated for HCV, and 20% had cirrhosis. Overall, 322 patients (96%) had a sustained virologic response at 12 weeks after the end of therapy (95% confidence interval [CI], 93 to 98), including rates of 96% (95% CI, 93 to 98) in patients with HCV genotype 1a, 96% (95% CI, 89 to 99) in those with HCV genotype 1b, and 100% (95% CI, 63 to 100) in those with HCV genotype 4. Rates of sustained virologic response were similar regardless of previous treatment or the presence of cirrhosis. Of the 13 patients who did not have a sustained virologic response, 10 had a relapse after the end of treatment. No patient had confirmed HIV-1 virologic rebound. The most common adverse events were headache (25%), fatigue (21%), and diarrhea (11%). No patient discontinued treatment because of adverse events. CONCLUSIONS: Ledipasvir and sofosbuvir for 12 weeks provided high rates of sustained virologic response in patients coinfected with HIV-1 and HCV genotype 1 or 4. (Funded by Gilead Sciences; ION-4 ClinicalTrials.gov number, NCT02073656.).

A phase I randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, and immunogenicity of a live-attenuated quadrivalent dengue vaccine in flavivirus-naïve and flavivirus-experienced healthy adults.

Dengue (DENV) is a mosquito-borne virus with four serotypes causing substantial morbidity in tropical and subtropical areas worldwide. V181 is an investigational, live, attenuated, quadrivalent dengue vaccine. In this phase 1 double-blind, placebo-controlled study, the safety, tolerability, and immunogenicity of V181 in baseline flavivirus-naïve (BFN) and flavivirus-experienced (BFE) healthy adults were evaluated in two formulations: TV003 and TV005. TV005 contains a 10-fold higher DENV2 level than TV003. Two-hundred adults were randomized 2:2:1 to receive TV003, TV005, or placebo on Days 1 and 180. Immunogenicity against the 4 DENV serotypes was measured using a Virus Reduction Neutralization Test (VRNT60) after each vaccination and out to 1 year after the second dose. There were no discontinuations due to adverse events (AE) or serious vaccine-related AEs in the study. Most common AEs after TV003 or TV005 were headache, rash, fatigue, and myalgia. Tri- or tetravalent vaccine-viremia was detected in 63.9% and 25.6% of BFN TV003 and TV005 participants, respectively, post-dose 1 (PD1). Tri- or tetravalent dengue VRNT60 seropositivity was demonstrated in 92.6% of BFN TV003, 74.2% of BFN TV005, and 100% of BFE TV003 and TV005 participants PD1. Increases in VRNT60 GMTs were observed after the first vaccination with TV003 and TV005 in both flavivirus subgroups for all dengue serotypes, and minimal increases were measured PD2. GMTs in the TV003 and TV005 BFE and BFN groups remained above the respective baselines and placebo through 1-year PD2. These data support further development of V181 as a single-dose vaccine for the prevention of dengue disease.

Doravirine dose selection and 96-week safety and efficacy versus efavirenz in antiretroviral therapy-naive adults with HIV-1 infection in a Phase IIb trial.

BACKGROUND: The safety and efficacy of doravirine were compared with that of efavirenz as initial treatment of adults living with HIV-1 infection (NCT01632345). METHODS: A Phase IIb double-blind trial with participants stratified by screening HIV-1 RNA (≤ or >100,000 copies/ml) and randomized 1:1:1:1:1 to receive once-daily doravirine (25, 50, 100 or 200 mg) or efavirenz 600 mg (Part I) for up to 96 weeks, with open-label tenofovir disoproxil fumarate 300 mg/emtricitabine 200 mg (TDF/FTC). After dose selection at week 24, doravirine 100 mg was provided to participants receiving the other doses of doravirine and additional participants were randomized 1:1 to receive once-daily doravirine 100 mg or efavirenz 600 mg for 96 weeks with TDF/FTC (Part II). Primary outcomes were the proportion of participants with HIV-1 RNA <40 copies/ml at week 24, and central nervous system (CNS) adverse events (AEs) by weeks 8 and 24 (Parts I+II combined). RESULTS: 210 and 132 participants were randomized in Parts I and II, respectively, and 216 (108 on doravirine 100 mg, 108 on efavirenz) were evaluable for Parts I+II combined. At week 24, the proportion of participants with HIV-1 RNA <40 copies/ml was 72.9% for doravirine 100 mg and 73.1% for efavirenz (difference -0.5 [95% CI -12.3, 11.2]). In addition, CNS AEs were reported by 26.9% and 47.2% of doravirine and efavirenz recipients, respectively (difference -20.4 [95% CI -32.6, -7.5]; P=0.002). CONCLUSIONS: Doravirine 100 mg with TDF/FTC demonstrated similar antiretroviral activity and superior CNS safety compared with efavirenz 600 mg with TDF/FTC.

Safety, efficacy, and dose response of the maturation inhibitor GSK3532795 (formerly known as BMS-955176) plus tenofovir/emtricitabine once daily in treatment-naive HIV-1-infected adults: Week 24 primary analysis from a randomized Phase IIb trial.

GSK3532795 (formerly known as BMS-955176) is a second-generation maturation inhibitor targeting a specific Gag cleavage site between capsid p24 and spacer peptide 1 of HIV-1. Study 205891 (previously AI468038) investigated the efficacy, safety, and dose response of GSK3532795 in treatment-naive, HIV-1-infected participants. Study 205891 (NCT02415595) was a Phase IIb, randomized, active-controlled, double-blind, international trial. Participants were randomized 1:1:1:1 to one of three GSK3532795 arms at doses 60 mg, 120 mg or 180 mg once daily (QD), or to efavirenz (EFV) at 600 mg QD, each in combination with tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) (300/200 mg QD). Primary endpoint was proportion of participants with plasma HIV-1 RNA <40 copies/mL at Week 24. Between May 2015 and May 2016, 206 participants received treatment. At Week 24, 76-83% participants receiving GSK3532795 and 77% receiving EFV achieved HIV-1 RNA <40 copies/mL. Fifteen participants receiving GSK3532795 and one receiving EFV met resistance testing criteria; 10/15 receiving GSK3532795 had emergent substitutions at reverse transcriptase positions M184, and one at position K65, while the participant receiving EFV did not have any nucleoside reverse transcriptase inhibitor (NRTI)/non-NRTI mutations. EFV, relative to GSK3532795, had more serious adverse events (9% versus 5%) and adverse events leading to discontinuation (17% versus 5%). However, 3-4-fold higher rates of gastrointestinal adverse events were observed with GSK3532795 relative to EFV. GSK3532795 combined with TDF/FTC is efficacious with 24 weeks of therapy. However, GSK3532795 showed a higher rate of gastrointestinal intolerability and treatment-emergent resistance to the NRTI backbone relative to EFV. Trial registration: ClinicalTrials.gov NCT02415595.

Efficacy and safety of tenofovir alafenamide versus tenofovir disoproxil fumarate given as fixed-dose combinations containing emtricitabine as backbones for treatment of HIV-1 infection in virologically suppressed adults: a randomised, double-blind, active-controlled phase 3 trial.

BACKGROUND: Emtricitabine with tenofovir disoproxil fumarate is a standard-of-care nucleoside reverse transcriptase inhibitor (NRTI) backbone. However, tenofovir disoproxil fumarate is associated with renal and bone toxic effects; the novel prodrug tenofovir alafenamide achieves 90% lower plasma tenofovir concentrations. We aimed to further assess safety and efficacy of fixed-dose combination emtricitabine with tenofovir alafenamide in patients switched from emtricitabine with tenofovir disoproxil fumarate. METHODS: In this controlled, double-blind, multicentre phase 3 study, we recruited virologically suppressed (HIV RNA <50 copies per mL) patients with HIV aged 18 years and older receiving regimens containing fixed-dose combination emtricitabine with tenofovir disoproxil fumartate from 78 sites in North America and Europe. Patients were randomly assigned (1:1) to switch to fixed-dose 200 mg emtricitabine with 10 mg or 25 mg tenofovir alafenamide or to continue 200 mg emtricitabine with 200 mg or 300 mg tenofovir disoproxil fumarate, while remaining on the same third agent for 96 weeks. Randomisation was done by a computer-generated allocation sequence and was stratified by the third agent (boosted protease inhibitor vs other agent). Investigators, patients, and study staff giving treatment, assessing outcomes, and collecting data were masked to treatment group. The primary outcome was the proportion of patients with plasma HIV-1 RNA less than 50 copies per mL at week 48 as defined by the US Food and Drug Administration snapshot algorithm with a prespecified non-inferiority margin of 10%. The primary efficacy endpoint was analysed with the per-protocol analysis set, whereas the safety analysis included all randomly assigned patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT02121795. FINDINGS: We recruited patients between May 6, 2011, and Sept 11, 2014; 780 were screened and 668 were randomly assigned to receive either tenofovir alafenamide (n=333) or tenofovir disoproxil fumarate (n=330). Through week 48, virological success (HIV-1 RNA <50 copies per mL) was maintained in 314 (94%) of patients in the tenofovir alafenamide group compared with 307 (93%) in the tenofovir disoproxil fumarate group (difference 1·3%, 95% CI -2·5 to 5·1), showing non-inferiority of tenofovir alafenamide to tenofovir disproxil fumarate. Seven patients in the tenofovir alafenamide (2%) and three (1%) in the tenofovir disoproxil fumarate group discontinued due to adverse events. There were no cases of proximal renal tubulopathy in either group. INTERPRETATION: In patients switching from emtricitabine with tenofovir disoproxil fumarate to emtricitabine with tenofovir alafenamide, high rates of virological suppression were maintained. With its safety advantages, fixed-dose emtricitabine with tenofovir alafenamide has the potential to become an important NRTI backbone. FUNDING: Gilead Sciences.

A Phase II, Randomized, Safety and Immunogenicity Trial of a Re-Derived, Live-Attenuated Dengue Virus Vaccine in Healthy Children and Adults Living in Puerto Rico.

This was a double-blind, randomized, controlled, phase II clinical trial, two dose study of re-derived, live-attenuated, tetravalent dengue virus (TDEN) vaccine (two formulations) or placebo in subjects 1-50 years of age. Among the 636 subjects enrolled, 331 (52%) were primed, that is, baseline seropositive to at least one dengue virus (DENV) type. Baseline seropositivity prevalence increased with age (10% [< 2 years], 26% [2-4 years], 60% [5-20 years], and 93% [21-50 years]). Safety profiles of TDEN vaccines were similar to placebo regardless of priming status. No vaccine-related serious adverse events (SAEs) were reported. Among unprimed subjects, immunogenicity (geometric mean antibody titers [GMT] and seropositivity rates) for each DENV increased substantially in both TDEN vaccine groups with at least 74.6% seropositive for four DENV types. The TDEN vaccine candidate showed an acceptable safety and immunogenicity profile in children and adults ranging from 1 to 50 years of age, regardless of priming status. ClinicalTrials.gov: NCT00468858.

Forty-eight-week efficacy and safety and early CNS tolerability of doravirine (MK-1439), a novel NNRTI, with TDF/FTC in ART-naive HIV-positive patients.

INTRODUCTION: Doravirine (DOR) is an investigational NNRTI (aka MK-1439) that retains activity against common NNRTI-resistant mutants. We have previously reported the Part 1 results from a two-part, randomized, double-blind, Phase IIb study in ART-naïve HIV-1-positive patients (1). At doses of 25, 50, 100 and 200 mg qd, DOR plus open-label tenofovir/emtricitabine (TDF/FTC) demonstrated potent antiretroviral activity comparable to EFV 600 mg qhs plus TDF/FTC and was generally well tolerated at week 24. DOR 100 mg was selected for use in patients continuing in Part 1 and those newly enrolled in Part 2. METHODS: Patients receiving DOR 25, 50 or 200 mg in Part 1 were switched to 100 mg after dose selection. In Part 2, 132 additional patients were randomized 1:1 to DOR 100 mg qd or EFV 600 mg qhs (each with TDF/FTC). We present week 48 efficacy and safety results for all patients in Part 1, and early (week 8) CNS tolerability only for patients randomized to DOR 100 mg or to EFV in Parts 1 and 2 combined. The primary safety endpoint is the % of patients with pre-specified CNS events (all causality) by week 8 for DOR 100 mg qd vs EFV (Parts 1 + 2 combined). RESULTS: Part 1 week 48 efficacy and safety results are shown below. CONCLUSIONS: In ART-naïve, HIV-1-positive patients also receiving TDF/FTC, DOR 100 mg qd demonstrated potent antiretroviral activity and immunological effect at week 48 and was generally safe and well tolerated. Patients who received DOR 100 mg qd had significantly fewer treatment-emergent CNS AEs by week 8 than those who received EFV.

Sustained efficacy and safety of raltegravir after 5 years of combination antiretroviral therapy as initial treatment of HIV-1 infection: final results of a randomized, controlled, phase II study (Protocol 004).

Raltegravir as initial HIV therapy was examined in a double-blind study; 160 patients were randomized to raltegravir (400 mg bid after dose-ranging), 38 to efavirenz, both with tenofovir/lamivudine. At week 240, HIV-RNA remained <50 copies per milliliter in 68.8% (raltegravir) versus 63.2% (efavirenz), and CD4 increases were 302 versus 276 cells per microliter, respectively. Early HIV-RNA decline predicted later CD4 increases in both groups. Raltegravir resistance was observed in 3 of 10 raltegravir recipients with virologic failure. Few drug-related adverse events were reported after week 48. Raltegravir had minimal effect on laboratory values, including lipids. Raltegravir with tenofovir/lamivudine showed durable efficacy and good tolerability over 5 years.

Long-term efficacy, safety, and tolerability of rilpivirine (RPV, TMC278) in HIV type 1-infected antiretroviral-naive patients: week 192 results from a phase IIb randomized trial.

TMC278-C204 (NCT00110305), a 96-week trial of the nonnucleoside reverse transcription inhibitor (NNRTI) rilpivirine (RPV, TMC278) in 368 HIV-1-infected, treatment-naive patients, was extended to investigate long-term safety and efficacy. Week 192 analysis results are presented. This was a long-term follow-up of a Phase IIb, randomized trial. No significant RPV dose-response relationships with respect to the primary endpoint (composite ITT-TLOVR algorithm) were observed at week 48 or 96. All RPV-treated patients were switched to open-label 75 mg qd at week 96 and then to 25 mg qd, the Phase III dose, at approximately week 144 as it gave the best benefit-risk balance. All control patients continued receiving open-label efavirenz (EFV) 600 mg qd. At week 192, 59% of RPV- and 61% of EFV-treated patients maintained confirmed viral load <50 copies/ml (ITT-TLOVR algorithm). The mean changes from baseline in CD4 cell count were similar in both groups (RPV: 210 cells/mm(3) vs. EFV: 225 cells/mm(3)). No new safety concerns were noted between week 48 and 192. In the week 192 analysis, RPV compared with EFV was associated with a lower overall incidence of grade 2-4 adverse events (AEs) at least possibly related to treatment, including rash (p<0.001) and neurologic AEs (p<0.05 Fisher's exact test, post hoc analyses) Incidences of serious AEs, grade 3 or 4 AEs, and discontinuations due to AEs were similar across groups. Increases in total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides were significantly lower with RPV than with EFV. RPV continued to show sustained efficacy similar to EFV at week 192 with a generally more favorable safety profile.

Efficacy and safety of TMC278 in antiretroviral-naive HIV-1 patients: week 96 results of a phase IIb randomized trial.

OBJECTIVE: TMC278 is a next-generation nonnucleoside reverse transcriptase inhibitor highly active against wild-type and nonnucleoside reverse transcriptase inhibitor-resistant HIV-1 in vitro. The week 96 analysis of TMC278-C204, a large dose-ranging study of TMC278 in treatment-naive HIV-1-infected patients, is presented. DESIGN: Phase IIb randomized trial. METHODS: Three hundred sixty-eight patients were randomized and treated with three blinded once-daily TMC278 doses 25, 75 or 150 mg, or an open-label, active control, efavirenz 600 mg once daily, all with two nucleoside reverse transcriptase inhibitors. The primary analysis was at week 48. RESULTS: No TMC278 dose-response relationship for efficacy and safety was observed. TMC278 demonstrated potent antiviral efficacy comparable with efavirenz over 48 weeks that was sustained to week 96 (76.9-80.0% and 71.4-76.3% of TMC278-treated patients with confirmed viral load <50 copies/ml, respectively; time-to-loss of virological-response algorithm). Median increases from baseline in CD4 cell count with TMC278 at week 96 (138.0-149.0 cells/microl) were higher than at week 48 (108.0-123.0 cells/microl). All TMC278 doses were well tolerated. The incidences of the most commonly reported grade 2-4 adverse events at least possibly related to study medication, including nausea, dizziness, abnormal dreams/nightmare, dyspepsia, asthenia, rash, somnolence and vertigo, were low and lower with TMC278 than with efavirenz. Incidences of serious adverse events, grade 3 or 4 adverse events and discontinuations due to adverse events were similar among groups. CONCLUSION: All TMC278 doses demonstrated potent and sustained efficacy comparable with efavirenz in treatment-naive patients over 96 weeks. TMC278 was well tolerated with lower incidences of neurological and psychiatric adverse events, rash and lower lipid elevations than those with efavirenz. TMC278 25 mg once daily was selected for further clinical development.

Simplification of antiretroviral therapy to a single-tablet regimen consisting of efavirenz, emtricitabine, and tenofovir disoproxil fumarate versus unmodified antiretroviral therapy in virologically suppressed HIV-1-infected patients.

OBJECTIVE: To evaluate a simplification strategy for HIV-1-infected patients virologically suppressed on antiretroviral therapy (ART) by switching to a single-tablet regimen consisting of efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF). DESIGN: : Prospective, randomized, controlled, open-label, multicenter study. METHODS: Patients on stable ART with HIV-1 RNA <200 copies per milliliter for > or = 3 months were stratified by prior nonnucleoside reverse transcriptase inhibitor-based or protease inhibitor-based therapy and randomized (2:1) to simplify treatment to EFV/FTC/TDF or to stay on their baseline regimen (SBR). Efficacy and safety assessments were performed at baseline and at weeks 4, 12, 24, 36, and 48. Additional patient-reported outcomes included the following: adherence by visual analog scale, quality of life by SF-36 (v2) survey, HIV Symptom Index, and the Preference of Medication and Perceived Ease of the Regimen for Condition questionnaires. RESULTS: Three hundred patients (EFV/FTC/TDF 203, SBR 97) were evaluated (prior protease inhibitor-based ART, 53%; nonnucleoside reverse transcriptase inhibitor-based ART, 47%). The arms were well balanced at baseline with 88% males, 29% blacks, and a mean age of 43 years; CD4 was 540 cells per cubic millimeter, 96% had HIV-1 RNA <50 copies per milliliter, and 88% were on their first ART regimen. Through 48 weeks, 89% vs. 88% in the EFV/FTC/TDF vs. SBR arms, respectively, maintained HIV-1 RNA <200 copies per milliliter by time to loss of virologic response algorithm (intent to treat, noncompleters = failures) with the difference (95% confidence interval) between arms of 1.1% (-6.7% to 8.8%), indicating noninferiority of EFV/FTC/TDF vs. SBR. Similarly, maintenance of HIV-1 RNA <50 copies per milliliter by time to loss of virologic response algorithm was 87% vs. 85% for EFV/FTC/TDF vs. SBR, respectively [difference (95% confidence interval) 2.6% (-5.9% to 11.1%)]. Discontinuation rates were similar (EFV/FTC/TDF 11%, SBR 12%); more discontinuations for adverse events occurred in the EFV/FTC/TDF arm vs. SBR (5% vs. 1%), most commonly for nervous system symptoms. More patients withdrew consent in the SBR arm vs. EFV/FTC/TDF (7% vs. 2%). Estimated glomerular filtration rate (by Modification of Diet in Renal Disease) remained unchanged over 48 weeks in both arms (median change < 1 mL.min.1.73 m). A decrease in fasting triglycerides was observed at 48 weeks in the EFV/FTC/TDF vs. SBR arm (-20 vs. -3.0 mg/dL; P = 0.035). Adherence of > or = 96% was reported by visual analog scale in both arms at baseline and at all study visits. CONCLUSION: Simplification to EFV/FTC/TDF maintained high and comparable rates of virologic suppression vs. SBR through 48 weeks.

Sustained antiretroviral effect of raltegravir after 96 weeks of combination therapy in treatment-naive patients with HIV-1 infection.

OBJECTIVES: The purpose of this study was to evaluate the safety and efficacy of raltegravir vs efavirenz-based antiretroviral therapy after 96 weeks in treatment-naive patients with HIV-1 infection. METHODS: Multicenter, double-blind, randomized study of raltegravir (100, 200, 400, or 600 mg twice a day) vs efavirenz (600 mg every day), both with tenofovir/lamivudine (TDF/3TC), for 48 weeks, after which raltegravir arms were combined and all dosed at 400 mg twice a day. Eligible patients had HIV-1 RNA > or =5000 copies per milliliter and CD4 T cells > or =100 cells per microliter. RESULTS: One hundred ninety-eight patients were randomized and treated; 160 received raltegravir and 38 received efavirenz. At week 96, 84% of patients in both groups achieved HIV-1 RNA <400 copies per milliliter; 83% in the raltegravir group and 84% in the efavirenz group achieved <50 copies per milliliter (noncompleter = failure). Both groups showed similar increases in CD4 T cells (221 vs 232 cells/uL, respectively). An additional 2 patients (1 in each group) met the protocol definition of virologic failure between weeks 48 and 96; no known resistance mutations were observed in the raltegravir recipient; the efavirenz recipient had nucleoside reverse transcriptase inhibitor and nonnucleoside reverse transcriptase inhibitor resistance mutations. Investigator reported drug-related clinical adverse events (AEs) were less frequent with raltegravir (51%) than efavirenz (74%). Drug-related AEs occurring in >10% of patients in either group were nausea in both groups and dizziness and headache in the efavirenz group. Laboratory AEs remained infrequent. Raltegravir had no adverse effect on total or low-density lipoprotein cholesterol or on triglycerides. Neuropsychiatric AEs remained less frequent with raltegravir (34%) than efavirenz (58%). There were no drug-related serious AEs in patients receiving raltegravir. CONCLUSIONS: In antiretroviral therapy-naive patients, raltegravir with TDF/3TC had potent antiretroviral activity, which was similar to efavirenz/TDF/3TC and was sustained to week 96. Raltegravir was generally well tolerated; drug-related AEs were less frequent in patients treated with raltegravir compared with efavirenz.

Rapid and durable antiretroviral effect of the HIV-1 Integrase inhibitor raltegravir as part of combination therapy in treatment-naive patients with HIV-1 infection: results of a 48-week controlled study.

BACKGROUND: Raltegravir is an HIV-1 integrase strand-transfer inhibitor with potent in vitro activity. This study explored the antiretroviral activity and safety of raltegravir in treatment-naive patients with plasma HIV-1 RNA levels > or = 5000 copies/mL and CD4 T-cell counts > or = 100 cells/mm. METHODS: Multicenter, double-blind, randomized, controlled study of raltegravir at doses of 100, 200, 400, and 600 mg twice daily versus efavirenz at a dose of 600 mg/d, all in combination with tenofovir at a dose of 300 mg/d and lamivudine at a dose of 300 mg/d (clinicaltrials.gov identifier: NCT00100048). RESULTS: In the 198 patients treated (160 on raltegravir and 38 on efavirenz), the mean HIV-1 RNA level ranged from 4.6 to 4.8 log10 copies/mL at baseline. At weeks 2, 4, and 8, the proportion of patients achieving an HIV-1 RNA level <50 copies/mL was greater in each of the raltegravir treatment groups than in the efavirenz group. By week 24, all treatment groups appeared similar, with plasma HIV-1 RNA levels <400 copies/mL in 85% to 98% of patients and <50 copies/mL in 85% to 95% of patients. These reductions were maintained through week 48 in 85% to 98% of patients and in 83% to 88% of patients, respectively. Five (3%) patients on raltegravir and 1 (3%) on efavirenz experienced virologic failure before week 48. Drug-related clinical adverse events were less common with raltegravir than with efavirenz. After 24 and 48 weeks of treatment, raltegravir did not result in increased serum levels of total cholesterol, low-density lipoprotein cholesterol, or triglycerides. CONCLUSIONS: Raltegravir at all doses studied was generally well tolerated in combination with tenofovir and lamivudine. Raltegravir exhibited potent and durable antiretroviral activity similar to that of efavirenz at 24 and 48 weeks but achieved HIV-1 RNA levels below detection at a more rapid rate.

Antiretroviral activity, pharmacokinetics, and tolerability of MK-0518, a novel inhibitor of HIV-1 integrase, dosed as monotherapy for 10 days in treatment-naive HIV-1-infected individuals.

BACKGROUND: MK-0518 is a novel HIV-1 integrase strand transfer inhibitor with potent in vitro activity against HIV-1 (95% inhibitory concentration [IC95] = 33 nM in 50% human serum) and good bioavailability in uninfected subjects. This study explored the antiretroviral activity and safety of MK-0518 versus placebo for 10 days as monotherapy in antiretroviral therapy-naive HIV-1-infected patients with plasma HIV-1 RNA levels of at least 5000 copies/mL and CD4 T-cell counts of at least 100 cells/mm. METHODS: This was a multicenter, double-blind, randomized, placebo-controlled 2-part study, with the first part using MK-0518 in 1 of 4 doses (100, 200, 400, and 600 mg) versus placebo (randomized 1:1:1:1:1) given twice daily for 10 days of monotherapy. Patients were monitored for safety, pharmacokinetic parameters, and antiretroviral effect. RESULTS: Thirty-five patients were enrolled (6-8 patients per treatment group) and completed 10 days of therapy; the mean baseline log10 HIV RNA level ranged from 4.5 to 5.0 copies/mL in each group. On day 10, the mean decrease from baseline in the log10 HIV RNA level was -0.2 copies/mL for the placebo group and -1.9, -2.0, -1.7 and -2.2 log10 copies/mL for the MK-0518 100-, 200-, 400-, and 600-mg treatment groups, respectively. All dose groups had superior antiretroviral activity compared with placebo (P < 0.001 for comparison of each dose with placebo). At least 50% of patients in each MK-0518 dose group achieved an HIV RNA level <400 copies/mL by day 10. Mean trough MK-0518 concentrations at each dose exceeded the IC95 of 33 nM. Study therapy was generally well tolerated. The most common adverse experiences were headache and dizziness; these were similar between active and control groups. There were no discontinuations because of adverse experiences and no serious adverse experiences. CONCLUSIONS: MK-0518 showed potent antiretroviral activity as short-term monotherapy and was generally well tolerated at all doses. Based on these results, part 2 of the study, a dose-ranging 48-week trial of MK-0518 versus efavirenz in a combination regimen, has been initiated.