Long-term efficacy and safety of atazanavir with stavudine and lamivudine in patients previously treated with nelfinavir or atazanavir

The purpose of the study was to determine long-term efficacy, safety, and tolerability of atazanavir plus stavudine/lamivudine in 346 HIV-infected patients previously treated with atazanavir or nelfinavir. BMS AI424-044 is an ongoing, multicenter, international, open-label, rollover/switch study initiated in June 2001. Patients completing >or=48 weeks in trial BMS AI424-008 with a plasma HIV RNA viral load <10,000 copies/mL were eligible to continue on atazanavir (400 or 600 mg) or to switch from nelfinavir to atazanavir (400 mg) once daily. Antiviral efficacy, change in CD4 cell counts, and effect on lipid parameters were measured. After 24 weeks of atazanavir use in BMS AI424-044, 83%, 85%, and 87% of the atazanavir 400-mg, atazanavir 600-mg, and nelfinavir-to-atazanavir-switched patients, respectively, had HIV RNA levels <400 copies/mL compared with 76%, 76%, and 63%, respectively, at week 48 of BMS AI424-008. Atazanavir-treated patients showed minimal changes in lipid levels compared with baseline. Patients switched from nelfinavir to atazanavir showed significant mean percent decreases in total cholesterol (-16%), fasting low-density lipoprotein cholesterol (-21%), and fasting triglycerides (-28%) (P<0.0001) by week 12 of atazanavir treatment. No new safety issues were identified, and the overall incidence of treatment-emergent adverse events during BMS AI424-044 was comparable across treatment groups. Atazanavir was safe, tolerable, and effective during extended use and in patients switched from nelfinavir. Extended atazanavir use resulted in continued viral suppression and lipid changes that were not clinically relevant. In virologically suppressed nelfinavir-treated patients switched to atazanavir, virologic improvement continued, whereas nelfinavir-induced lipid elevations were reversed within 12 weeks, approaching pretreatment values.     

Antiviral activity of enteric-coated didanosine,stavudine, and nelfinavir versus zidovudine plus lamivudine and nelfinavir

OBJECTIVE: To assess and compare the activity and safety of capsules containing enteric-coated beadlets of didanosine given once daily with stavudine and nelfinavir with that of a standard reference triple drug regimen of zidovudine plus lamivudine and nelfinavir. DESIGN: Multinational, 49-site, prospective, open-label, randomized, two-arm comparison study. PARTICIPANTS: HIV-infected subjects with limited or no previous antiretroviral therapy who had plasma HIV RNA levels of >or=2000 copies/mL and CD4 cell counts of >or=200/mm3 (511 were randomized to treatment groups, and 352 completed the study). INTERVENTIONS: Triple antiretroviral therapy for 48 weeks: didanosine EC (400 mg once daily), stavudine (40 mg twice daily), and nelfinavir (750 mg three times daily) or a twice-daily coformulation of zidovudine (300 mg) plus lamivudine (150 mg) and nelfinavir (750 mg three times daily). MAIN OUTCOME MEASURE: Proportion of subjects with HIV RNA levels of <400 copies/mL at week 48 based on an "intent-to-treat, missing = treatment failure" analysis. RESULTS: The two treatment groups were similar in the proportion of treatment responders (i.e., HIV RNA level of <400 copies/mL), with 54% of subjects in the didanosine EC and zidovudine plus lamivudine treatment groups responding at week 48. Results of other analyses supported those of the primary analysis. The two study regimens were associated with similar numbers of adverse events. CONCLUSIONS: The antiviral efficacy of a triple combination regimen containing once-daily didanosine EC is similar to that of a reference triple combination regimen.     

Results of a phase 2 clinical trial at 48 weeks (AI424-007): a dose-ranging,safety, and efficacy comparative trial of atazanavir at three doses in combination with didanosine and stavudine in antiretroviral-naive subjects

Three dose levels of the protease inhibitor (PI) atazanavir (200, 400, and 500 mg once daily) were compared with nelfinavir (750 mg three times daily) when given both as monotherapy and in combination with didanosine and stavudine in 420 antiretroviral-naive subjects infected with HIV-1. Subjects received monotherapy for 2 weeks, followed by combination therapy for 46 weeks. After 48 weeks, mean change from baseline in HIV RNA (-2.57 to -2.33 log 10 copies/mL), the proportion of subjects with HIV RNA <400 copies/mL (56%-64%) and <50 copies/mL (28%-42%), and mean increases in CD4 cell count (185-221 cells/mm 3) were comparable across treatment groups. Diarrhea was two to three times more common in the nelfinavir group (61% of subjects) than in the atazanavir groups (23%-30% of subjects, <.0001 versus nelfinavir), and jaundice occurred only in atazanavir-treated subjects (6%, 6%, and 12% in the 200-, 400-, and 500-mg groups, respectively) ( <.03 for all atazanavir regimens vs. nelfinavir). Mean percent change from baseline in fasting low-density lipoprotein (LDL) cholesterol was significantly less in the atazanavir groups (-7% to 4%) than in the nelfinavir group (31%) ( <.0001). In conclusion, once-daily atazanavir is a potent, safe, and well tolerated PI that rapidly and durably suppresses HIV RNA and durably increases CD4 cell count in antiretroviral-naive subjects. Through 48 weeks, atazanavir was not associated with clinically relevant increases in total cholesterol, fasting LDL cholesterol, or fasting triglycerides. In comparison, nelfinavir was associated with prompt, marked, and sustained elevations in these parameters of a magnitude that suggests they are clinically relevant.     

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.     

Tenofovir disoproxil fumarate, emtricitabine, and efavirenz versus fixed-dose zidovudine/lamivudine and efavirenz in antiretroviral-naive patients: virologic, immunologic, and morphologic changes--a 96-week analysis

BACKGROUND: In antiretroviral-naive patients, tenofovir disoproxil fumarate (TDF), emtricitabine (FTC), and efavirenz (EFV) demonstrated superior outcomes compared with fixed-dose zidovudine (ZDV)/lamivudine (3TC) and EFV through 48 weeks. Results through a 96-week extension phase are presented. METHODS: In this randomized, open-label, noninferiority trial, 517 antiretroviral-naive HIV-infected patients received TDF, FTC, and EFV (TDF + FTC + EFV) or ZDV/3TC and EFV (ZDV/3TC + EFV). The primary endpoint was the proportion of patients with an HIV RNA level <400 copies/mL in patients without baseline nonnucleoside resistance. RESULTS: Through week 96, significantly more patients receiving TDF + FTC + EFV achieved and maintained an HIV RNA level <400 copies/mL (75% receiving TDF + FTC + EFV vs. 62% receiving ZDV/3TC + EFV; P = 0.004). There was a trend toward greater virologic suppression to <50 copies/mL in the TDF + FTC + EFV group (67% vs. 61%; P = 0.16). The TDF + FTC + EFV group demonstrated a significantly greater increase in CD4 count (270 vs. 237 cells/mm; P = 0.036). No patient developed the K65R mutation. Limb fat at week 96 was significantly greater in the TDF + FTC + EFV group versus the ZDV/3TC + EFV group (7.7 vs. 5.5 kg; P < 0.001). CONCLUSION: Over 96 weeks, the combination of TDF, FTC, and EFV was superior to fixed-dose ZDV/3TC + EFV for achieving and maintaining an HIV RNA level <400 copies/mL and an increase in CD4 cells.     

Efficacy and safety of atazanavir, with or without ritonavir, as part of once-daily highly active antiretroviral therapy regimens in antiretroviral-naive patients

BACKGROUND: Atazanavir (ATV), the first once-daily protease inhibitor approved for the treatment of HIV-1 infection, is recommended for use in antiretroviral (ARV) treatment-naive and -experienced patients. Study AI424-089 was a prospective, randomized, open-label, 96-week study comparing 2 ATV-based treatment regimens in ARV-naive HIV-infected patients. METHODS: Adults with HIV RNA levels > or =2000 copies/mL were randomized (1:1) to once-daily ATV at a dose of 300 mg with ritonavir at a dose of 100 mg (ATV300/RTV) or ATV at a dose of 400 mg (ATV400); both regimens included lamivudine and an investigational extended-release formulation of stavudine. The primary endpoint for this noninferiority study was the proportion of patients (response rate) with an HIV RNA load <400 copies/mL at week 48. RESULTS: Response rates at week 48 were 86% and 85% on the ATV300/RTV and ATV400 regimens, respectively (difference estimate [95% confidence interval] = 1.5 [-8.2 to 11.1]). There were 3 and 10 patients with virologic failure in the ATV300/RTV and ATV400 groups, respectively. One patient (ATV400) developed phenotypic resistance to ATV associated with an I50L substitution. Adverse event-related discontinuations were 8% among ATV300/RTV-treated patients and <1% among ATV400-treated patients. Plasma lipid elevations were low with both regimens. Both regimens were well tolerated. CONCLUSIONS: These findings demonstrate the safety and efficacy of the ATV300/RTV regimen and confirm the safety and efficacy of ATV400 in an ARV-naive patient population.     

Pilot Study of Once-Daily Simplification Therapy with Abacavir/Lamivudine/Zidovudine and Efavirenz for Treatment of HIV-1 Infection

Abstract

Objective: The purpose of this pilot study was to explore the efficacy and safety of the abacavir/lamivudine/zidovudine fixed-dose combination tablet administered as two tablets once daily (qd) versus one tablet twice daily (bid) in combination with efavirenz (EFV). Method: This was a prospective, randomized, open-label, multicenter study with a 24-week treatment period in 7 outpatient HIV clinics in the United States. Patients currently receiving an initial regimen of abacavir/lamivudine/zidovudine bid plus EFV qd for at least 6 months with HIV-1 RNA <50 copies/mL for at least 3 months and a screening CD4+ cell count ≥200 cells/mm³ were eligible. Thirty-six patients enrolled, and 35 (97%) completed the study. Participants were randomized to switch to 2 tablets of abacavir/lamivudine/zidovudine qd plus EFV qd (QD arm) or continue current treatment (BID arm) for 24 weeks. Results: Efficacy, safety, and adherence were evaluated. Median baseline CD4+ cell count was 521 cells/mm³. At week 24, HIV-1 RNA <50 copies/mL was achieved for 94% of participants in the QD arm and 89% in the BID arm by intent-to-treat, missing = failure analysis (95% confidence interval for difference: ≥0.29 to +0.18, p = 1.000). At week 24, median CD4+ cell count change from baseline was +26 cells/mm³ for the QD arm and –39 cells/mm³ for BID arm. One patient randomized to the QD arm met virologic failure criteria (confirmed HIV-1 RNA >120 copies/mL) at week 20 and viral genotype showed M184V. After failure, this patient revealed he never took EFV throughout the entire study after randomization, effectively receiving only abacavir/lamivudine/zidovudine qd alone. Median adherence was slightly higher in the QD arm, although both arms had broad variability and overlapping interquartile ranges. Adverse events were infrequent and occurred with similar frequency between arms; treatment-related adverse events were abdominal pain, flatulence, nausea, headache, and abnormal dreams (1 patient [3%] for each adverse event). No patients withdrew due to adverse events, and no abacavir hypersensitivity reactions were reported. Conclusion: In this pilot study of patients suppressed on abacavir/lamivudine/zidovudine bid plus EFV, 94% of participants switching to abacavir/lamivudine/zidovudine qd plus EFV maintained virologic suppression, compared to 89% of participants continuing abacavir/lamivudine/zidovudine bid plus EFV.     

Induction with abacavir/lamivudine/zidovudine plus efavirenz for 48 weeks followed by 48-week maintenance with abacavir/lamivudine/zidovudine alone in antiretroviral-naive HIV-1-infected patients

BACKGROUND: The ESS40013 study tested 4-drug induction followed by 3-drug maintenance as initial antiretroviral therapy (ART) to reduce HIV RNA rapidly and then to simplify to an effective yet more convenient and tolerable regimen. METHODS: Four hundred forty-eight antiretroviral-naive adults were treated with abacavir/lamivudine/zidovudine (ABC/3TC/ZDV) and efavirenz (EFV) for the 48-week induction phase. Two hundred eighty-two patients were randomized in a 1:1 ratio to continue ABC/3TC/ZDV+EFV or to simplify to ABC/3TC/ZDV for the 48-week maintenance phase. RESULTS: The baseline median HIV RNA level and CD4 cell count were 5.08 log10 copies/mL (56%>or=100,000 copies/mL) and 210 cells/mm (48% <200 cells/mm), respectively. No significant differences were noted between ABC/3TC/ZDV+EFV and ABC/3TC/ZDV for an HIV RNA level <50 copies/mL (79% vs. 77% [intent to treat (ITT), missing=failure]; P=0.697) or time to treatment failure (P=0.75) at week 96. Drug-related adverse events were more commonly reported for ABC/3TC/ZDV+EFV than for ABC/3TC/ZDV (15% vs. 6%). Improvements in total cholesterol, low-density lipoprotein cholesterol, and triglycerides were observed in the ABC/3TC/ZDV group. Virologic failure occurred in 22 patients during induction and in 24 patients (16 in ABC/3TC/ZDV group and 8 in ABC/3TC/ZDV+EFV group; P=0.134) during maintenance. A greater proportion of patients receiving ABC/3TC/ZDV than ABC/3TC/ZDV+EFV reported perfect adherence at week 96 (88.8% vs. 79.6%; P=0.057). CONCLUSIONS: After induction with ABC/3TC/ZDV+EFV, simplification to ABC/3TC/ZDV alone maintained virologic control and immunologic response, reduced fasting lipids and ART-associated adverse events, and improved adherence.     

The effects of the Roche AMPLICOR HIV-1 MONITOR UltraSensitive Test versions 1.0 and 1.5 viral load assays and plasma collection tube type on determination of response to antiretroviral therapy and the inappropriateness of cross-study comparisons.

BACKGROUND: Because there are limited head-to-head data comparing antiretroviral combinations, physicians are tempted to rely on cross-trial comparisons to evaluate the relative efficacy of HIV drugs. However, a variety of factors can confound these comparisons, resulting in misleading or invalid conclusions. OBJECTIVES: To compare and evaluate the use of: (i) versions 1.0 and 1.5 of the Roche AMPLICOR HIV-1 MONITOR UltraSensitive assay, and (ii) ethylenediaminetetraacetic acid (EDTA) and plasma preparation (PPT) tubes on the proportion of HIV-infected patients who would be classified as virological responders in a multinational clinical trial. STUDY DESIGN: The study utilized was a randomized, double-blind trial comparing the efficacy and safety of atazanavir with efavirenz, each in combination with fixed-dose zidovudine/lamivudine, in antiretroviral-na?ve patients. To evaluate the effect of monitor kit version, paired plasma samples from 634 patients at week 48 were analyzed using both versions 1.0 and 1.5 of the monitor kit. To evaluate the effect of collection tube type, paired plasma samples collected from 584 patients at week 52 using both EDTA and PPT tubes were assayed. Patients were classified as responders if HIV-1 RNA levels were below a pre-determined level of quantification (LOQ), both 400 and 50 copies/ml. RESULTS AND CONCLUSIONS: Substantially higher HIV-1 RNA levels were observed with monitor kit version 1.5, resulting in lower response rates. The version 1.0 monitor kit resulted in a 7% increase in patients classified as responders at the LOQ of 400 copies/ml and a 13% increase at the LOQ of 50 copies/ml. Consistently higher response rates (11% higher at the LOQ of 400 copies/ml and 34% higher at the LOQ of 50 copies/ml) were also observed when samples were collected in EDTA tubes compared with PPT tubes. Differences in monitor kit sensitivity and plasma collection procedures are key factors in study results and suggest caution when performing cross-study comparisons.     

A Pilot Study of Abacavir/Lamivudine and Raltegravir in Antiretroviral-Naïve HIV-1–Infected Patients: 48-Week Results of the SHIELD Trial

Abstract

Purpose: To evaluate raltegravir plus abacavir/lamivudine in antiretroviral-naïve, HIV-1–infected patients. Methods: SHIELD is an ongoing 96-week pilot study of abacavir/lamivudine 600 mg/300 mg once daily with raltegravir 400 mg twice daily among HLA-B*5701-negative adults with screening viral load (VL) >1,000 copies/mL. HBsAg+ patients were excluded, as were patients with key mutation(s) to any study drug. Virologic failure (VF) was defined as either VL >400 copies/mL at week 24 or confirmed virologic rebound. Results: Thirty-five patients enrolled (mean age 38.7 years). Most were white males, but 26% self-identified as Hispanic/Latino. At baseline, 34% had VL ≥100,000 copies/mL (median, 4.8 log₁₀ copies/mL) and 20% had CD4 cell counts <200 cells/mm³ (median, 301). One patient discontinued due to adverse events (AEs); one patient experienced VF. At week 48, 91% (32/35) had VL <50 and <400 copies/mL by missing/discontinuation equals failure analysis. Median CD4 cell count change from baseline was +247 cells/mm³. Five patients (14%) had treatment-related grade 2–4 AEs; no treatment–related serious AEs were reported. Over 48 weeks, median fasting lipids increased for total (+17%), LDL (+9%), and HDL (+6%) cholesterol but remained stable for triglycerides (–1%) and total:HDL cholesterol ratio (0%). Conclusions: In this pilot study, abacavir/lamivudine plus raltegravir was effective and generally well-tolerated over 48 weeks with modest changes in fasting lipids.     

Unboosted Atazanavir Plus Co-formulated Lamivudine/Abacavir as a Ritonavir-Sparing Simplification Strategy in Routine Clinical Practice

Abstract

Objective: To assess the effectiveness and safety of antiretroviral therapy with unboosted atazanavir (400 mg once daily) plus co-formulated abacavir/lamivudine as a treatment simplification strategy in HIV-infected patients with sustained viral suppression in routine clinical practice. Methods: We performed a retrospective study including patients who were switched to unboosted atazanavir plus abacavir/lamivudine and whose HIV-1 RNA was <50 copies/mL. The primary endpoint was the percentage of subjects who maintained viral suppression after 48 weeks of follow-up. Secondary endpoints included the percentage of subjects who maintained viral suppression after 96 weeks of follow-up, the incidence of adverse events, changes in CD4+ T-cell count and in lipid profile, and the percentage of patients with subtherapeutic atazanavir trough concentrations during follow-up. Results: Forty-six patients were included. None had a prior history of resistance to protease inhibitors or to lamivudine or abacavir. The percentage of patients with viral suppression at Week 48 was 73.9% when all the included patients were considered (full dataset analysis) and 85.0% when only subjects on treatment were considered. There was a continuous immune recovery and an improvement in lipid profile during follow-up. Two thirds of the patients had subtherapeutic atazanavir trough concentrations in plasma in at least one determination during follow-up. Conclusion: Antiretroviral therapy with unboosted atazanavir plus abacavir/lamivudine is safe and effective in the long term as a treatment simplification strategy in HIV-infected patients with sustained virological suppression in routine clinical practice.     

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)

ABSTRACT:: 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.     

Once-Daily Abacavir/Lamivudine and Ritonavir-Boosted Atazanavir for the Treatment of HIV-1 Infection in Antiretroviral-Naïve Patients: A 48-Week Pilot Study

Abstract

Purpose: To assess the efficacy and safety of a once-daily (QD) regimen consisting of the co-formulation of abacavir/lamivudine (ABC/3TC) and atazanavir plus ritonavir (ATV-RTV) in antiretroviral (ART)-naïve patients with plasma HIV-1 RNA >5,000 copies/mL. Method: This open-label, multicenter study conducted between September 2004 and June 2006 included 112 patients who received ABC 600 mg/3TC 300 mg and ATV 300 mg-RTV 100 mg QD. Drug switches were permitted for ABC hypersensitivity and ATV-related hyperbilirubinemia. Primary endpoints were proportion of patients achieving HIV-1 RNA <50 copies/mL at Week 48 and treatment discontinuation due to study drugs. Results: A total of 111 patients were treated. At Week 48, the proportion of patients achieving HIV-1 RNA <50 copies/mL was 77% (85/111) by intent-to-treat (ITT) missing=failure, switch included response rate. Drug substitutions occurred in 8 (7%) patients for suspected ABC hypersensitivity reaction (HSR) and in 6 (5%) patients for ATV-related toxicities; only 1 patient discontinued study due to ABC HSR. Four patients met confirmed virologic nonresponse (HIV RNA ?400 copies/mL). Treatment-emergent drug resistance was rare, and no patient had virus that developed reduced susceptibility to ATV. Median change from baseline (95% confidence interval) in fasting lipids at Week 48 was 39 (26–66) mg/dL for triglycerides, 28 (22–38) mg/dL for total cholesterol (C), 14 (10.5–16) mg/dL for HDL-C, and 8 (2–16.5) mg/dL for LDL-C. Conclusion: ABC/3TC and ATV-RTV QD is an effective and well-tolerated regimen in ART-naïve patients through 48 weeks, with a modest impact on fasting lipids.     

Compact Quadruple Therapy with the Lamivudine/Zidovudine Combination Tablet Plus Abacavir and Efavirenz,Followed by the Lamivudine/Zidovudine/Abacavir Triple Nucleoside Tablet Plus Efavirenz in Treatment-Naïve HIV-Infected Adults

Abstract

Purpose: To assess efficacy, safety, and adherence with compact quadruple therapy comprising one lamivudine 150-mg/zidovudine 300-mg tablet (COM) twice daily + one abacavir (ABC) 300-mg tablet twice daily + three efavirenz (EFV) 200-mg capsules at bedtime for 24 weeks, followed by one lamivudine 150-mg/zidovudine 300-mg/ABC 300-mg triple nucleoside tablet (TZV) twice daily + three EFV 200-mg capsules at bedtime for 24 weeks. Method: A pilot 48-week, prospective, open-label trial in which 38 antiretroviral-naïve HIV-infected adults (baseline median HIV-1 RNA 5.1 log₁₀ copies/mL, CD4+ cell count 285/μL) received the above treatment and were monitored regularly with respect to plasma HIV-1 RNA levels, CD4+ cell counts, T-cell receptor excision circles (TRECs), adherence, and adverse events. Results: At Week 48, intent-to-treat, switch-included analysis showed plasma HIV-1 RNA levels <400 copies/mL in 100% (29/29) of patients and <50 copies/mL in 93% (27/29); 59% of patients who achieved <50 copies/mL had <3 copies/mL (16/27). Similar virologic suppression was observed in patients with baseline HIV-1 RNA above or below 100,000 copies/mL. HIV-1 RNA and CD4+ cell counts changed from baseline by a median of –3.4 log₁₀ copies/mL and +172 cells/μL, respectively. One virologic failure occurred at Week 16. Median TRECs/100,000 peripheral blood lymphocytes increased 6-fold between baseline and Week 48. Median adherence rates were consistently 100% by self-report and 94% by pill count. Grade 2-4 treatment-related adverse events included dreams (16%), nausea (13%), decreased white cells (8%), dizziness (8%), sleep disorders (8%), and malaise and fatigue (8%). A suspected ABC hypersensitivity reaction occurred in 8% (3/38) of patients. Conclusion: COM/ABC/EFV or TZV/EFV produced potent, durable virologic suppression and immunologic benefits, was associated with high adherence rates, and was generally well tolerated.     

Efficacy and Safety of Ritonavir-Boosted and Unboosted Atazanavir Among Antiretroviral-Naïve Patients

Abstract

Purpose: Evaluate responses and safety of ritonavir-boosted atazanavir (“boosted atazanavir”) compared to unboosted atazanavir among antiretroviral-naïve patients in the clinical managed care setting. Method: Observational cohort analysis of atazanavir use (comparing ritonavir-boosted to non-boosted) at Kaiser Permanente and Group Health Cooperative from 2003 to 2006. Antiretroviral-naïve patients initiating atazanavir were followed through 52 weeks of treatment. Results: 443 patients were prescribed atazanavir (69 non-boosted; 15.5%). Boosted and non-boosted atazanavir groups were similar with respect to gender and age. Boosted atazanavir use was associated with greater odds achieving HIV RNA <400 c/mL (odds ratio [OR] = 3.24, p = .008), greater decrease in HIV RNA (?0.37 log₁₀/mL, p = .03), greater increase in CD4 T-cell count (+59 cells/μL, p = .01), and greater increase in total bilirubin (+1.21 mg/dL as opposed to +0.56 mg/dL, p ? .001). There were no statistically significant differences for glucose, liver transaminases, total cholesterol, or LDL cholesterol elevations. There were greater odds of maximal viral control when atazanavir was combined with tenofovir or zidovudine in combination with lamivudine (or emtricitabine). Conclusions: Ritonavir-boosted atazanavir is associated with greater virologic control and immune response through 52 weeks compared to non-boosted atazanavir, without greater risk of adverse events except elevated bilirubin. Thus, ritonavir-boosted atazanavir is the preferred method of prescribing atazanavir.     

The Safety and Efficacy of Switching Stavudine to Tenofovir DF in Combination with Lamivudine and Efavirenz in HIV-1—Infected Patients: Three-Year Follow–up After Switching Therapy

Abstract

Background: Study 903 is a phase 3 trial with a completed 144-week, double-blind phase comparing tenofovir DF (TDF) with stavudine (d4T), in combination with lamivudine (3TC) and efavirenz (EFV), and an ongoing 336-week open-label extension phase. Method: Patients in 3 countries completing the d4T treatment phase were allowed to switch d4T to TDF and receive once-daily TDF+3TC+EFV in the extension phase. Results: At the time of switch, 100% and 99% of patients (n = 85; 60% male, 64% White; mean age 37 years; mean CD4 = 650 cells/mm3) had HIV RNA <400 and <50 copies/mL. At 144 weeks after the switch, 89% (missing = failure) had HIV RNA <400 copies/mL and 87% had HIV RNA <50 copies/mL. Mean CD4 cell count increased 155 cells/mm3. No patient had virologic failure. Significant decreases from switch to week 144 in mean fasting total cholesterol (?22 mg/dL, p < .0001) and triglycerides (?78 mg/dL, p < .0001) were observed. Mean limb fat increased significantly from 4.5 kg to 5.8 kg, 144 weeks after switch (p < .0001). Conclusion: In virologically suppressed patients, switching d4T to TDF as part of a once-daily regimen with 3TC and EFV resulted in maintenance of virologic suppression and continued CD4 cell increases through 144 weeks, with significant improvements in metabolic parameters.