Simplification with abacavir-based triple nucleoside therapy versus continued protease inhibitor-based highly active antiretroviral therapy in HIV-1-infected patients with undetectable plasma HIV-1 RNA. Abacavir/lamivudine/zidovudine maintenance after standard induction in antiretroviral therapy-naïve patients: FREE randomized trial interim results. Triple-nucleoside regimens versus efavirenz-containing regimens for the initial treatment of HIV-1 infection. Second-line antiretroviral therapy in resource-limited settings: the experience of Médecins Sans Frontières. Antiretroviral treatment simplification with 3 NRTIs or 2 NRTIs plus nevirapine in HIV-1-infected patients treated with successful first-line HAART. A randomized controlled trial to evaluate antiretroviral salvage therapy guided by rules-based or phenotype-driven HIV-1 genotypic drug-resistance interpretation with or without concentration-controlled intervention: the Resistance and Dosage Adapted Regimens (RADAR) study. [Clinical trial comparing efficacy and safety of four highly active antiretroviral therapy (HAART) in antiretroviral-naive treatment with advanced HIV infection]. High rate of early virological failure with the once-daily tenofovir/lamivudine/nevirapine combination in naive HIV-1-infected patients. Maintenance therapy after quadruple induction therapy in HIV-1 infected individuals: Amsterdam Duration of Antiretroviral Medication (ADAM) study.
To assess the antiviral efficacy, safety and adherence in patients switched to an abacavir-containing nucleoside reverse transcriptase inhibitor (NRTI) regimen after long-term HIV-1 RNA suppression with a dual NRTI/protease inhibitor (PI) combination.
                In an open-label, multicentre study, patients receiving 2NRTI plus PI for at least 6 months, with a history of undetectable plasma HIV-1 RNA since the initiation of therapy and plasma HIV-1 RNA < 50 copies/ml at screening, were randomly assigned to replace the PI with abacavir (n = 105) or continue the same treatment (n = 106). Clinical assessments included plasma HIV-1 RNA, chemistry, haematology, lymphocyte counts, and adverse event reports. Adherence to treatment was assessed by patient self-report.
                A significantly longer time to treatment failure was demonstrated in the abacavir arm compared with the PI arm (P = 0.03) while treatment failure was experienced by significantly more patients in the PI arm: 24 (23%) versus 12 (12%) (P = 0.03). Therapy-limiting toxicity led to treatment failure in eight versus 14 cases in the abacavir and PI arms, respectively, whereas virological rebound was the cause in four versus two cases. Significant reductions in cholesterol and non-fasting triglyceride plasma levels at 48 weeks were observed in the abacavir arm (P < 0.001 andP = 0.035, respectively). The number of patients reporting no difficulty in taking their therapy showed a marked increase from baseline in the abacavir arm.
                The replacement of PI by abacavir in a triple combination regimen following prolonged suppression of plasma HIV-1 RNA provides continued virological suppression, significant improvements in lipid abnormalities and enhanced ease of dosing. Maintenance with a triple nucleoside reverse transcriptase Inhibitor (NRTI) regimen after successful induction with a dual NRTI/protease inhibitor (PI) combination may be advantageous, because of low pill burden, favorable lipids, and less drug interactions. This strategy to become free of PI-related problems without losing viral efficacy has not been formally tested. We performed a randomized, open-label, multicenter, 96-week comparative study in antiretroviral therapy (ART)-naïve patients with CD4 <or=350 cells/mm(3) and HIV-1 RNA concentrations (viral load [VL]) greater than 30,000 copies per milliliter. Patients were randomized after reaching VL less than 50 copies per milliliter on two consecutive occasions between 12 and 24 weeks after start of zidovudine/lamuvidine and lopinavir/ritonavir combination. Eligible subjects switched to abacavir/lamivudine/zidovudine (TZV) or continued the PI-containing regimen. Here we present the 48-week data with virologic success rate (failure: VL > 50 copies per milliliter). Two hundred seven patients had similar baseline (BL) characteristics: median CD4 180 cells/mm(3), median VL 5.19 log(10) copies per milliliter. One hundred twenty subjects (58%) met randomization criteria. Baseline VL differed significantly between dropouts and randomized subjects (median 5.41 versus 5.06 log(10) copies per milliliter, p = 0.017), as did CD4 cells (median 160 and 200 cells/mm(3), p = 0.044). Sixty-one subjects received TZV and 59 subjects continued NRTIs/PI. At week 48, 2 patients in the TZV group and 5 in the PI group did not have a sustained virologic suppression (log rank test; p = 0.379). CD4 counts increased significantly in both arms. In ART-naïve patients, TZV maintenance had similar antiviral efficacy compared to continued standard ART at 48 weeks after baseline. Patients on successful standard ART can be safely switched to a NRTI-only regimen, at least for the tested time period. Regimens containing three nucleoside reverse-transcriptase inhibitors offer an alternative to regimens containing nonnucleoside reverse-transcriptase inhibitors or protease inhibitors for the initial treatment of human immunodeficiency virus type 1 (HIV-1) infection, but data from direct comparisons are limited.
                This randomized, double-blind study involved three antiretroviral regimens for the initial treatment of subjects infected with HIV-1: zidovudine-lamivudine-abacavir, zidovudine-lamivudine plus efavirenz, and zidovudine-lamivudine-abacavir plus efavirenz.
                We enrolled a total of 1147 subjects with a mean baseline HIV-1 RNA level of 4.85 log10 (71,434) copies per milliliter and a mean CD4 cell count of 238 per cubic millimeter were enrolled. A scheduled review by the data and safety monitoring board with the use of prespecified stopping boundaries led to a recommendation to stop the triple-nucleoside group and to present the results in the triple-nucleoside group in comparison with pooled data from the efavirenz groups. After a median follow-up of 32 weeks, 82 of 382 subjects in the triple-nucleoside group (21 percent) and 85 of 765 of those in the combined efavirenz groups (11 percent) had virologic failure; the time to virologic failure was significantly shorter in the triple-nucleoside group (P<0.001). This difference was observed regardless of the pretreatment HIV-1 RNA stratum (at least 100,000 copies per milliliter or below this level; P< or =0.001 for both comparisons). Changes in the CD4 cell count and the incidence of grade 3 or grade 4 adverse events did not differ significantly between the groups.
                In this trial of the initial treatment of HIV-1 infection, the triple-nucleoside combination of abacavir, zidovudine, and lamivudine was virologically inferior to a regimen containing efavirenz and two or three nucleosides.
                Copyright 2004 Massachusetts Medical Society To describe the use of second-line protease-inhibitor regimens in Médecins Sans Frontières HIV programmes, and determine switch rates, clinical outcomes, and factors associated with survival.
                We used patient data from 62 Médecins Sans Frontières programmes and included all antiretroviral therapy-naive adults (> 15 years) at the start of antiretroviral therapy and switched to a protease inhibitor-containing regimen with at least one nucleoside reverse transcriptase inhibitor change after more than 6 months of nonnucleoside reverse transcriptase inhibitor first-line use. Cumulative switch rates and survival curves were estimated using Kaplan-Meier methods, and mortality predictors were investigated using Poisson regression.
                Of 48,338 adults followed on antiretroviral therapy, 370 switched to a second-line regimen after a median of 20 months (switch rate 4.8/1000 person-years). Median CD4 cell count at switch was 99 cells/microl (interquartile ratio 39-200; n = 244). A lopinavir/ritonavir-based regimen was given to 51% of patients and nelfinavir-based regimen to 43%; 29% changed one nucleoside reverse transcriptase inhibitor and 71% changed two nucleoside reverse transcriptase inhibitors. Median follow-up on second-line antiretroviral therapy was 8 months, and probability of remaining in care at 12 months was 0.86. Median CD4 gains were 90 at 6 months and 135 at 12 months. Death rates were higher in patients in World Health Organization stage 4 at antiretroviral therapy initiation and in those with CD4 nadir count less than 50 cells/microl.
                The rate of switch to second-line treatment in antiretroviral therapy-naive adults on non-nucleoside reverse transcriptase inhibitor-based first-line antiretroviral therapy was relatively low, with good early outcomes observed in protease inhibitor-based second-line regimens. Severe immunosuppression was associated with increased mortality on second-line treatment. To assess the virologic noninferiority of an antiretroviral treatment simplification with coformulated zidovudine/lamivudine/abacavir (group 1) vs. coformulated zidovudine/lamivudine plus nevirapine (group 2) in HIV-1-infected patients receiving successful first-line highly active antiretroviral therapy.
                This is a prospective, multicenter, open-label, comparative, randomized, noninferiority study. A delta of 15% for differences in virologic suppression <200 copies/mL between groups was prespecified with a 1-sided 0.025 significance level.
                A total of 134 patients were included into this study: 68 were allocated to group 1 and 66 to group 2. By intention-to-treat analysis (switch equals failure), the percentage of virologic suppression <200 copies/mL (<50 copies/mL) at week 48 was 71.0% (65.1%) and 73.0% (63.3%) in groups 1 and 2, respectively (estimate for differences [<200 copies/mL]: -2.1, 95% CI: -17.4-13.1, P=0.783). Thirteen and 14 patients in groups 1 and 2, respectively, discontinued therapy due to adverse events. Dyslipidemia improved in both groups, with a higher improvement in low-density lipoprotein cholesterol (P=0.049) in group 1.
                Group 1 is not inferior to group 2 regarding virologic suppression <200 copies/mL. Both strategies improve lipid profile. It is not well defined whether concentration-controlled intervention (CCI) and rules-based human immunodeficiency virus (HIV) type 1 genotype drug-resistance interpretation (GI) or virtual phenotype drug-resistance interpretation (VPI) may improve the outcome of HIV salvage therapy.
                In a prospective, randomized, controlled trial, patients were randomized (on a factorial basis) to change treatment after either GI or VPI, and they then were further randomized to the control arm (no CCI) or the CCI arm. Protease inhibitor (PI) and nonnucleoside reverse-transcriptase inhibitor (NNRTI) trough concentration (Ctrough) values were determined at weeks 1, 4, 12, and 24 of the study.
                Among 230 patients, virological benefit (defined by an HIV RNA load of <400 copies/mL at week 24) was not statistically different, either between patients in the GI and VPI arms or between patients in the CCI and control arms. A virological benefit was found for patients in the CCI arm, compared with patients in the control arm, but this benefit was not statistically significant (56.8% vs. 64.3% at week 4 and 63.6% vs. 74% at week 12). Dosage adaptation was possible for only a fraction of patients, because of low rates of treatment adherence or patient refusal to increase dosages. In the logistic regression analysis, independent predictors of virological response at week 24 were a PI Ctrough value and/or an NNRTI Ctrough value in the higher quartiles (or above cutoff levels) and a low number of PIs previously received. Moreover, receipt of a regimen that contained PIs boosted with ritonavir was an independent predictor of virological response.
                The present study did not support the routine use of CCI for patients undergoing salvage treatment, probably as a result of existing difficulties associated with its clinical application. However, a higher Ctrough value appeared to be correlated with treatment response. No major differences were found between VPI or GI when they are used together with expert advice for the selection of salvage treatment combinations. Comparison of efficacy and safety of four highly active antiretroviral therapy regimens (HAART) including two nucleoside analogues (NA) and a protease inhibitor (PI) in HIV positive patients with advanced infection and antiretroviral naive.
                Multicenter, randomized and open labeled clinical trial in ten community hospitals of Castilla-La Mancha and Madrid. Regimen 1 contains zidovudine (AZT), lamivudine (3TC) and indinavir (IDV) regimen 2 includes AZT, 3TC and ritonavir (RTV), regimen 3 was didanosine (DDI), estavudine (D4T) and IDV, and regimen 4 included DDI, D4T and RTV. Decrease in viral load of HIV (VC) has been assessed as primary endpoint and as secondary one, the increase of the numbers of CD4 lymphocytes, percentage of disease progression, adverse reactions and adherence. Measurements were made at baseline visit and at 6, 12, 24, 36 and 48 weeks.
                A total of 98 patients with a mean baseline CD4 count of 122 x 10(6)/l (range of 5-340) and a baseline viral load of 5.1 log copies/ml were included. At 48 weeks, a mean increase of the CD4 and decrease of the viral load without significant difference between the 4 regimens (103 cells/2.62 log in regimen 1; 169 cells/2.86 log in regimen 2; 171 cells/2.56 log in regimen 3 and 141 cells/1.71 log in regimen 4) were observed in the analysis of the patients in treatment. Treatment was discontinued due to adverse reactions: 24% in regimen 1, 48% in regimen 2, 26% in regimen 3 and 32% in regimen 4, without significant difference. Analyzing by PI groups, 41% of the patients with RTV and 25% of those with IDV discontinued treatment due to adverse effects. There was withdrawal from treatment due to disease progression in 7% of the RTV patients and in 9% of IDV patients.
                In the HIV positive patients with advanced infection, efficacy between the four regimens of HAART is similar, but there is a tendency to require more withdrawal due to adverse effects in the RTV group than in those of IDV, the two used as single PI. The combination of one non-nucleoside reverse transcriptase inhibitor (NNRTI) with two nucleoside reverse transcriptase inhibitors is a validated first-line antiretroviral (ARV) therapy. The once-daily combination of lamivudine, tenofovirDF and nevirapine has not been evaluated in a clinical trial.
                Randomized, open-label, multicentre, non-inferiority trial comparing lamivudine, tenofovirDF and nevirapine once daily (Group 2) with zidovudine/lamivudine and nevirapine twice daily (Group 1), in naive HIV-1-infected patients with a CD4 count <350/mm(3). We planned to enroll 250 patients.
                As of May 2006, 71 patients had been enrolled (35 in Group 1 and 36 in Group 2) and an unplanned interim analysis was done. The groups were comparable at baseline: median CD4 count was 195 and 191/mm(3) and median plasma viral load was 4.9 log(10) and 5.01 log(10), respectively, in Groups 1 and 2. Eight early non-responses (22.2%) were observed, all in Group 2, while two later viral rebounds occurred. Resistance genotypes for the nine Group 2 failing patients showed the mutations M184V/I (n = 3), K65R (n = 6), one or more NNRTI resistance mutations in all cases. At baseline, the nine Group 2 patients who failed had higher median plasma viral load (5.4 log(10)) and lower median CD4 count (110/mm(3)) than the other Group 2 patients (4.7 log(10), P = 0.002 and 223/mm(3), P = 0.004). Nevirapine trough concentrations were not different between the two groups, nor between patients with full viral suppression or those who failed in Group 2. Due to slow recruitment, and those results, the steering committee decided to stop the trial at 12 months.
                In ARV-naive HIV-1-infected patients, the once-daily lamivudine, tenofovirDF and nevirapine regimen resulted in a high rate of early virological failures. The reasons for the failures remain unclear. Highly active antiretroviral therapy (HAART) has led to health benefits for patients infected with HIV-1. However, long-term use of multidrug regimens is difficult to sustain. Simplifying antiretroviral treatment regimens would increase patients' adherence and minimise toxicity. We investigated the feasibility of a strategy of induction therapy followed by maintenance therapy with HAART in a randomised open-label study.
                From March, 1997, we enrolled patients infected with HIV-1 with at least 200 CD4 cells/microL, at least 1000 HIV-1 RNA copies/mL in plasma, and no previous exposure to antiretroviral drugs. After 26 weeks of induction therapy (stavudine, lamivudine, saquinavir, and nelfinavir) patients were randomly allocated maintenance therapy (either stavudine and nelfinavir or saquinivir and nelfinavir) or prolonged induction therapy (if the plasma HIV-1 RNA concentration at weeks 24 and 25 was <50 copies/mL).
                In February, 1998, we discontinued randomisation after an interim analysis. 62 patients had been enrolled. 39 (91%) of the 43 patients who were followed up for at least 26 weeks had an undetectable plasma HIV-1 RNA concentration at week 16. At week 26, 31 patients were randomly allocated treatment. Of these patients 25 had a total follow-up of at least 36 weeks. At week 36, a higher proportion of patients on maintenance therapy (nine [64%] of 14) had a detectable HIV-1 RNA than patients on prolonged induction therapy (one [9%] of 11, p=0.01). The initial virion-clearance rate during induction therapy was higher in five patients on maintenance therapy with a sustained undetectable plasma HIV-1 RNA concentration than in nine patients with recurrence of a detectable plasma HIV-1 RNA concentration at week 36 (0.35 vs 0.19 per day, respectively; p=0.0008).
                The induction regimen provided a rapid suppression of viral replication to below 50 copies/mL. However, suppression was not sustained in a considerable number of patients who went onto maintenance therapy. It is currently inadvisable to continue attempts at moving from induction to maintenance therapy in day-to-day practice.
The strategy of switching to triple nucleoside regimens shows weak evidence of lower incidence of side effects and a higher incidence of virologic failure in the 3NRTI group compared to controls. Simplification with 3NRTI holds the advantages of preserving other classes of antiretroviral drugs, to lower blood lipids, and to be cost effective and simple to administer.Thus, simplification with triple nucleoside regimens AZT + 3TC + ABC should be still considered for individuals who are unable to tolerate or have contraindications to NNRTI or PI based regimens. Additional data are needed on longer-term efficacy of triple NRTI regimens, particularly on the development of antiretroviral resistance. Though studies in the current review were conducted between 2001 and 2010, the large majority of patients from studies analysed received old PI regimens (e.g., indinavir, ritonavir, nelfinavir, saquinavir) not longer recommended by International Guidelines. Since current guidelines recommend new "lipid -friendly" PI, future studies should compare regimens containing these news PIs to triple NRTI regimens. More realistically, however, there are opportunities to examine these issues in existing cohorts.