Randi Leavitt

Safety and efficacy of raltegravir-based versus efavirenz-based combination therapy in treatment-naive patients with HIV-1 infection: a multicentre, double-blind randomised controlled trial

BACKGROUNDnUse of raltegravir with optimum background therapy is effective and well tolerated in treatment-experienced patients with multidrug-resistant HIV-1 infection. We compared the safety and efficacy of raltegravir with efavirenz as part of combination antiretroviral therapy for treatment-naive patients.nnnMETHODSnPatients from 67 study centres on five continents were enrolled between Sept 14, 2006, and June 5, 2008. Eligible patients were infected with HIV-1, had viral RNA (vRNA) concentration of more than 5000 copies per mL, and no baseline resistance to efavirenz, tenofovir, or emtricitabine. Patients were randomly allocated by interactive voice response system in a 1:1 ratio (double-blind) to receive 400 mg oral raltegravir twice daily or 600 mg oral efavirenz once daily, in combination with tenofovir and emtricitabine. The primary efficacy endpoint was achievement of a vRNA concentration of less than 50 copies per mL at week 48. The primary analysis was per protocol. The margin of non-inferiority was 12%. This study is registered with ClinicalTrials.gov, number NCT00369941.nnnFINDINGSn566 patients were enrolled and randomly allocated to treatment, of whom 281 received raltegravir, 282 received efavirenz, and three were never treated. At baseline, 297 (53%) patients had more than 100 000 vRNA copies per mL and 267 (47%) had CD4 counts of 200 cells per microL or less. The main analysis (with non-completion counted as failure) showed that 86.1% (n=241 patients) of the raltegravir group and 81.9% (n=230) of the efavirenz group achieved the primary endpoint (difference 4.2%, 95% CI -1.9 to 10.3). The time to achieve such viral suppression was shorter for patients on raltegravir than on efavirenz (log-rank test p<0.0001). Significantly fewer drug-related clinical adverse events occurred in patients on raltegravir (n=124 [44.1%]) than those on efavirenz (n=217 [77.0%]; difference -32.8%, 95% CI -40.2 to -25.0, p<0.0001). Serious drug-related clinical adverse events occurred in less than 2% of patients in each drug group.nnnINTERPRETATIONnRaltegravir-based combination treatment had rapid and potent antiretroviral activity, which was non-inferior to that of efavirenz at week 48. Raltegravir is a well tolerated alternative to efavirenz as part of a combination regimen against HIV-1 in treatment-naive patients.nnnFUNDINGnMerck.

Maintenance Antiretroviral Therapies in HIV-Infected Subjects with Undetectable Plasma HIV RNA after Triple-Drug Therapy

BACKGROUNDnCombination antiretroviral therapy with indinavir, zidovudine, and lamivudine can suppress the level of human immunodeficiency virus (HIV) RNA in plasma below the threshold of detection for two years or more. We investigated whether a less intensive maintenance regimen could sustain viral suppression after an initial response to combination therapy.nnnMETHODSnHIV-infected subjects who had CD4 cell counts greater than 200 per cubic millimeter, who had been treated with indinavir, lamivudine, and zidovudine, and who had less than 200 copies of HIV RNA per milliliter of plasma after 16, 20, and 24 weeks of induction therapy were randomly assigned to receive either continued triple-drug therapy (106 subjects), indinavir alone (103 subjects), or a combination of zidovudine and lamivudine (107 subjects). The primary end point was loss of viral suppression, which was defined as a plasma level of at least 200 copies of HIV RNA per milliliter on two consecutive measurements during maintenance therapy.nnnRESULTSnDuring maintenance treatment, 23 percent of the subjects receiving indinavir and 23 percent of those receiving zidovudine and lamivudine, but only 4 percent of those receiving all three drugs, had loss of viral suppression (P<0.001 for the comparison between triple-drug therapy and the other two maintenance regimens). Subjects with greater increases in CD4 cell counts during induction therapy, higher viral loads at base line (i.e., at the beginning of induction therapy), and slower rates of viral clearance were at greater risk for loss of viral suppression. The presence of zidovudine-resistance mutations in HIV RNA at base line was strongly predictive of the loss of viral suppression in subjects treated with zidovudine and lamivudine.nnnCONCLUSIONSnThe suppression of plasma HIV RNA after six months of treatment with indinavir, zidovudine, and lamivudine is better sustained by the continuation of these three drugs than by maintenance therapy with either indinavir alone or zidovudine and lamivudine.

Switch to a raltegravir-based regimen versus continuation of a lopinavir-ritonavir-based regimen in stable HIV-infected patients with suppressed viraemia (SWITCHMRK 1 and 2): two multicentre, double-blind, randomised controlled trials

BACKGROUNDnTo reduce lipid abnormalities and other side-effects associated with antiretroviral regimens containing lopinavir-ritonavir, patients might want to switch one or more components of their regimen. We compared substitution of raltegravir for lopinavir-ritonavir with continuation of lopinavir-ritonavir in HIV-infected patients with stable viral suppression on lopinavir-ritonavir-based combination therapy.nnnMETHODSnThe SWITCHMRK 1 and 2 studies were multicentre, double-blind, double-dummy, phase 3, randomised controlled trials. HIV-infected patients aged 18 years or older were eligible if they had documented viral RNA (vRNA) concentration below the limit of assay quantification for at least 3 months while on a lopinavir-ritonavir-based regimen. 707 eligible patients were randomly allocated by interactive voice response system in a 1:1 ratio to switch from lopinavir-ritonavir to raltegravir (400 mg twice daily; n=353) or to remain on lopinavir-ritonavir (two 200 mg/50 mg tablets twice daily; n=354), while continuing background therapy consisting of at least two nucleoside or nucleotide reverse transcriptase inhibitors. Primary endpoints were the mean percentage change in serum lipid concentrations from baseline to week 12; the proportion of patients with vRNA concentration less than 50 copies per mL at week 24 (with all treated patients who did not complete the study counted as failures) with a prespecified non-inferiority margin of -12% for each study; and the frequency of adverse events up to 24 weeks. Analyses were done according to protocol. These trials are registered with ClinicalTrials.gov, numbers NCT00443703 and NCT00443729.nnnFINDINGSn702 patients received at least one dose of study drug and were included in the efficacy and safety analyses for the combined trials (raltegravir, n=350; lopinavir-ritonavir, n=352). Percentage changes in lipid concentrations from baseline to week 12 were significantly greater (p<0.0001) in the raltegravir group than in the lopinavir-ritonavir group in each study, yielding combined results for total cholesterol -12.6%vs 1.0%, non-HDL cholesterol -15.0%vs 2.6%, and triglycerides -42.2%vs 6.2%. At week 24, 293 (84.4%, 95% CI 80.2-88.1) of 347 patients in the raltegravir group had vRNA concentration less than 50 copies per mL compared with 319 (90.6%, 87.1-93.5) of 352 patients in the lopinavir-ritonavir group (treatment difference -6.2%, -11.2 to -1.3). Clinical and laboratory adverse events occurred at similar frequencies in the treatment groups. There were no serious drug-related adverse events or deaths. The only drug-related clinical adverse event of moderate to severe intensity reported in 1% or more of either treatment group was diarrhoea, which occurred in ten patients in the lopinavir-ritonavir group (3%) and no patients in the raltegravir group. The studies were terminated at week 24 because of lower than expected virological efficacy in the raltegravir group compared with the lopinavir-ritonavir group.nnnINTERPRETATIONnAlthough switching to raltegravir was associated with greater reductions in serum lipid concentrations than was continuation of lopinavir-ritonavir, efficacy results did not establish non-inferiority of raltegravir to lopinavir-ritonavir.nnnFUNDINGnMerck.

Safety and Immunogenicity of a Replication-Incompetent Adenovirus Type 5 HIV-1 Clade B gag/pol/nef Vaccine in Healthy Adults

BACKGROUNDnThe safety and immunogenicity of the MRK adenovirus type 5 human immunodeficiency virus type 1 clade B gag/pol/nef vaccine, a replication-incompetent adenovirus type 5-vectored vaccine designed to elicit cell-mediated immunity against conserved human immunodeficiency virus proteins, was assessed in a phase 1 trial.nnnMETHODSnHealthy adults not infected with human immunodeficiency virus were enrolled in a multicenter, dose-escalating, blind, placebo-controlled study to evaluate a 3-dose homologous prime-boost regimen of the trivalent MRK adenovirus type 5 human immunodeficiency virus type 1 vaccine containing from 3 x 10(6) to 1 x 10(11) viral particles per 1-mL dose administered on day 1, during week 4 and during week 26. Adverse events were recorded for 29 days after each intradeltoid injection. The primary immunogenicity end point was the proportion of study participants with a positive unfractionated Gag-, Pol-, or Nef-specific interferon-gamma enzyme-linked immunosorbent spot response measured 4 weeks after administration of the last dose.nnnRESULTSnOf 259 randomized individuals, 257 (99%) received > or = 1 dose of vaccine or placebo and were included in the safety analyses. Enzyme-linked immunosorbent spot results were available for 217 study participants (84%) at week 30. No serious vaccine-related adverse events occurred. No study participant discontinued participation because of vaccine-related adverse events. The frequency of injection-site reactions was dose dependent. Vaccine doses of > or = 3 x 10(9) viral particles elicited positive enzyme-linked immunosorbent spot responses to > or = 1 vaccine component in > 60% of recipients. High baseline antibody titers against adenovirus type 5 diminished enzyme-linked immunosorbent spot responses at all doses except the 3 x 10(10) viral particle dose.nnnCONCLUSIONSnThe vaccine was generally well tolerated and induced cell-mediated immune responses against human immunodeficiency virus type 1 peptides in most healthy adults. Despite these findings, vaccination in a proof-of-concept trial with use of this vaccine was discontinued because of lack of efficacy.

Raltegravir versus efavirenz regimens in treatment-naive HIV-1-infected patients: 96-week efficacy, durability, subgroup, safety, and metabolic analyses

Background:We analyzed the 96-week results in the overall population and in prespecified subgroups from the ongoing STARTMRK study of treatment-naive HIV-infected patients. Methods:Eligible patients with HIV-1 RNA (vRNA) levels >5000 copies per milliliter and without baseline resistance to efavirenz, tenofovir, or emtricitabine were randomized in a double-blind noninferiority study to receive raltegravir or efavirenz, each combined with tenofovir/emtricitabine. Results:At week 96 counting noncompleters as failures, 81% versus 79% achieved vRNA levels <50 copies per milliliter in the raltegravir and efavirenz groups, respectively [Δ (95% confidence interval) = 2% (−4 to 9), noninferiority P < 0.001]. Mean change in baseline CD4 count was 240 and 225 cells per cubic millimeter in the raltegravir and efavirenz groups, respectively [Δ (95% confidence interval) = 15 (−13 to 42)]. Treatment effects were consistent across prespecified baseline demographic and prognostic subgroups. Fewer drug-related clinical adverse events (47% versus 78%; P < 0.001) occurred in raltegravir than efavirenz recipients. Both regimens had modest effects on serum lipids and glucose levels and on body fat composition. Conclusions:When combined with tenofovir/emtricitabine in treatment-naive patients, raltegravir exhibited durable antiretroviral activity that was noninferior to the efficacy of efavirenz through 96 weeks of therapy. Subgroup analyses were generally consistent with the overall findings. Both regimens were well tolerated.

Raltegravir once daily or twice daily in previously untreated patients with HIV-1: a randomised, active-controlled, phase 3 non-inferiority trial

BACKGROUNDnTwice-daily raltegravir with once-daily tenofovir-emtricitabine is an effective initial antiretroviral regimen for patients with HIV-1. On the basis of pharmacokinetic data suggesting efficacy of once-daily raltegravir and because adherence is often improved with once-daily dosing, we aimed to compare these dosing schedules.nnnMETHODSnIn our international, double-blind, randomised, phase 3 non-inferiority study, we enrolled antiretroviral-naive patients with HIV RNA loads of more than 5000 copies per mL and no baseline resistance to tenofovir or emtricitabine at 83 centres worldwide. We randomly allocated patients (1:1) by use of a computer-generated sequence to receive raltegravir once daily (two 400 mg tablets taken together every 24 h), or twice daily (one 400 mg tablet every 12 h), both in combination with once-daily co-formulated tenofovir 300 mg plus emtricitabine 150 mg. The primary outcome was virological response at 48 weeks (viral RNA loads <50 copies per mL) in patients who received at least one dose of study drug, counting non-completers as failure. We assessed non-inferiority in terms of the proportion of patients in both treatment groups who achieved the primary outcome, with a non-inferiority margin of -10%. This study is registered with ClinicalTrials.gov, number NCT00745823.nnnFINDINGSnFrom Oct 15, 2008, to Nov 2, 2009, we randomly allocated 775 patients, of whom 382 (99%) of 386 patients in the once-daily group and 388 (99%) of 389 in the twice-daily group received at least one dose of study drug. At baseline, 304 (39%) of 770 treated patients had viral loads of more than 100,000 copies per mL and 188 (24%) had CD4 cell counts of fewer than 200 cells per μL. 318 (83%) of 382 patients in the once-daily group had virological response compared with 343 (89%) of 386 in the twice-daily group (difference -5·7%, 95% CI -10·7 to -0·83; p=0·044). Serious adverse events were reported in 26 (7%) of 382 once-daily recipients and 40 (10%) of 388 twice-daily recipients, and adverse events leading to discontinuation occurred in four (1%) patients in each group.nnnINTERPRETATIONnDespite high response rates with both regimens, once-daily raltegravir cannot be recommended in place of twice-daily dosing.nnnFUNDINGnMerck.

Long-term Treatment With Raltegravir or Efavirenz Combined With Tenofovir/Emtricitabine for Treatment-Naive Human Immunodeficiency Virus-1–Infected Patients: 156-Week Results From STARTMRK

BACKGROUNDnWe compared 3 years of antiretroviral therapy with raltegravir or efavirenz as part of a combination regimen in the ongoing STARTMRK study of treatment-naive patients infected with human immunodeficiency virus (HIV).nnnMETHODSnEligible patients with HIV-1 RNA (vRNA) levels >5000 copies/mL and without baseline resistance to efavirenz, tenofovir, or emtricitabine were randomized in a double-blind, noninferiority study to receive raltegravir or efavirenz, each combined with tenofovir/emtricitabine. Outcomes included viral suppression, adverse events, and changes from baseline metabolic parameters. Dual energy X-ray absorptiometry scans were obtained on a convenience sample of patients at prespecified time points to assess changes in body fat composition.nnnRESULTSnAt week 156 counting noncompleters as failures, 212 (75.4%) of 281 versus 192 (68.1%) of 282 had vRNA levels <50 copies/mL in the raltegravir and efavirenz groups, respectively [Δ (95% CI) = 7.3% (-0.2, 14.7), noninferiority P < .001]. Mean changes from baseline CD4 count were 332 and 295 cells/mm³ in the raltegravir and efavirenz arms, respectively [Δ (95% CI) = 37 (4, 69)]. Consistent virologic and immunologic efficacy was maintained across prespecified demographic and baseline prognostic subgroups for both treatment groups. Fewer drug-related clinical adverse events (49% vs 80%; P < .001) occurred in raltegravir than efavirenz recipients, with discontinuations due to adverse events in 5% and 7%, respectively. Elevations in fasting lipid levels (including LDL- and HDL-cholesterol) were consistently lower in the raltegravir than efavirenz group (P < .005). Fat gain was 19% in 25 raltegravir recipients and 31% in 32 efavirenz recipients at week 156.nnnCONCLUSIONSnWhen combined with tenofovir/emtricitabine in treatment-naive patients, raltegravir produced durable viral suppression and immune restoration that was at least equivalent to efavirenz through 156 weeks of therapy. Both regimens were well tolerated, but raltegravir was associated with fewer drug-related clinical adverse events and smaller elevations in lipid levels. Clinical Trials Registration. NCT00369941.

Efficacy and Tolerability of 3 Nonnucleoside Reverse Transcriptase Inhibitor–Sparing Antiretroviral Regimens for Treatment-Naive Volunteers Infected With HIV-1: A Randomized, Controlled Equivalence Trial

Background nNon-nucleoside reverse transcriptase (NNRTI) inhibitor-based antiretroviral therapy is not suitable for all treatment-naive HIV-infected persons.BACKGROUNDnNonnucleoside reverse transcriptase inhibitor-based antiretroviral therapy is not suitable for all treatment-naive HIV-infected persons.nnnOBJECTIVEnTo evaluate 3 nonnucleoside reverse transcriptase inhibitor-sparing initial antiretroviral regimens to show equivalence for virologic efficacy and tolerability.nnnDESIGNnA phase 3, open-label study randomized in a 1:1:1 ratio with follow-up for at least 96 weeks. (ClinicalTrials.gov: NCT00811954).nnnSETTINGn57 sites in the United States and Puerto Rico.nnnPATIENTSnTreatment-naive persons aged 18 years or older with HIV-1 RNA levels greater than 1000 copies/mL without resistance to nucleoside reverse transcriptase inhibitors or protease inhibitors.nnnINTERVENTIONnAtazanavir, 300 mg/d, with ritonavir, 100 mg/d; raltegravir, 400 mg twice daily; or darunavir, 800 mg/d, with ritonavir, 100 mg/d, plus combination emtricitabine, 200 mg/d, and tenofovir disoproxil fumarate, 300 mg/d.nnnMEASUREMENTSnVirologic failure, defined as a confirmed HIV-1 RNA level greater than 1000 copies/mL at or after 16 weeks and before 24 weeks or greater than 200 copies/mL at or after 24 weeks, and tolerability failure, defined as discontinuation of atazanavir, raltegravir, or darunavir for toxicity. A secondary end point was a combination of virologic efficacy and tolerability.nnnRESULTSnAmong 1809 participants, all pairwise comparisons of incidence of virologic failure over 96 weeks showed equivalence within a margin of equivalence defined as -10% to 10%. Raltegravir and ritonavir-boosted darunavir were equivalent for tolerability, whereas ritonavir-boosted atazanavir resulted in a 12.7% and 9.2% higher incidence of tolerability discontinuation than raltegravir and ritonavir-boosted darunavir, respectively, primarily because of hyperbilirubinemia. For combined virologic efficacy and tolerability, ritonavir-boosted darunavir was superior to ritonavir-boosted atazanavir, and raltegravir was superior to both protease inhibitors. Antiretroviral resistance at the time of virologic failure was rare but more frequent with raltegravir.nnnLIMITATIONnThe trial was open-label, and ritonavir was not provided.nnnCONCLUSIONnOver 2 years, all 3 regimens attained high and equivalent rates of virologic control. Tolerability of regimens containing raltegravir or ritonavir-boosted darunavir was superior to that of the ritonavir-boosted atazanavir regimen.nnnPRIMARY FUNDING SOURCEnNational Institute of Allergy and Infectious Diseases.

A Randomized, Controlled Trial of Indinavir, Zidovudine, and Lamivudine in Adults with Advanced Human Immunodeficiency Virus Type 1 Infection and Prior Antiretroviral Therapy

A randomized, double-blind, multicenter study of indinavir, zidovudine, and lamivudine was conducted in 320 adults with human immunodeficiency virus type 1 (HIV-1) infection, </=50 CD4 cells/mm3, and extensive prior zidovudine therapy. Patients received indinavir, 800 mg every 8 h; zidovudine, 200 mg every 8 h, and lamivudine, 150 mg twice daily; or all 3 drugs for 24 weeks. In an intention-to-treat analysis, proportions of patients with HIV-1 RNA <500 and <50 copies/mL, respectively, at week 24 were 56% and 45% in the indinavir-zidovudine-lamivudine group, 3% and 2% in the indinavir group, and 0% in the zidovudine-lamivudine group. Observed mean CD4 cell increases were 95, 78, and 6 cells/mm3 in the three-, one-, and two-drug arms, respectively. Regimens were generally well tolerated. Patients with advanced HIV-1 infection benefit from triple therapy with indinavir, zidovudine, and lamivudine, although the proportion with optimal response appeared to be lower in patients with low CD4 cell counts.

A nucleoside- and ritonavir-sparing regimen containing atazanavir plus raltegravir in antiretroviral treatment-naïve HIV-infected patients: SPARTAN study results.

Abstract Background: Nucleoside and ritonavir (RTV) toxicities have led to increased interest in nucleoside reverse transcriptase inhibitors (NRTIs) and RTV-sparing antiretroviral regimens. SPARTAN was a multicenter, randomized, open-label, noncomparative pilot study evaluating the efficacy, safety, and resistance profile of an investigational NRTI- and RTV-sparing regimen (experimental atazanavir [ATV] dose 300 mg bid + raltegravir [RAL] 400 mg bid [ATV+RAL]). The reference regimen consisted of ATV 300 mg/RTV 100 mg qd + tenofovir (TDF) 300 mg/emtricitabine (FTC) 200 mg qd (ATV/r+TDF/FTC). Methods: Treatment-naïve HIV-infected patients with HIV-RNA ≥5,000 copies/mL were randomized 2:1 to receive twice-daily ATV+RAL (n=63) or once-daily ATV/r+TDF/FTC (n=31). Efficacy at 24 weeks was determined by confirmed virologic response (CVR; HIV-RNA <50 copies/mL) with noncom-pleters counted as failures based on all treated subjects. Results: The proportion of patients with CVR HIV RNA <50 copies/mL at week 24 was 74.6% (47/63) in the ATV+RAL arm and 63.3% (19/30) in the ATV/r+TDF/FTC arm. Systemic exposure to ATV in the ATV+RAL regimen was higher than historically observed with ATV/r+TDF/ FTC. Incidence of Grade 4 hyperbilirubinemia was higher on ATV+RAL (20.6%; 13/63) than on ATV/r+TDF/FTC (0%). The criteria for resistance testing (virologic failure [VF]: HIV-RNA ≥400 copies/mL) was met in 6/63 patients on ATV+RAL, and 1/30 on ATV/r+TDF/FTC; 4 VFs on ATV+RAL developed RAL resistance. Conclusions: ATV+RAL, an experimental NRTI- and RTV-sparing regimen, achieved virologic suppression rates comparable to current standards of care for treatment-naïve patients. The overall profile did not appear optimal for further clinical development given its development of resistance to RAL and higher rates of hyperbilirubinemia with twice-daily ATV compared with ATV/RTV.