How much fat loss is needed for lipoatrophy to become clinically evident?

The objective of this study was to evaluate how much limb fat is needed to be lost for lipoatrophy to become clinically evident. Antiretroviral drug-naive patients from a randomized trial comparing stavudine or abacavir plus lamivudine and efavirenz, who had subjective assessment to detect clinically evident lipoatrophy (standardized questionnaire) and objective measurements of limb fat (dual X-ray absorptiometry) at baseline, 48 weeks, and 96 weeks were included. ROC curves were used to assess the sensitivity and specificity of several cut-off values of absolute and percent limb fat loss for diagnosing lipoatrophy. Of 54 patients included, 13 (24%) had subjective lipoatrophy at 96 weeks. After 96 weeks, median limb fat change was -2.3 kg (interquartile range: -5.2, +0.2) and 0.4 kg (interquartile range: -7.2, +3.4) in patients with and without lipoatrophy, respectively. Median percent limb fat change was -45.5% (interquartile range: -78.0, +3.7) and 5.5% (interquartile range: -62.8, +95.6), respectively. The cut-off values of absolute and percent limb fat loss showing the best sensitivity and specificity values were -1.5 kg (sensitivity, 77%; specificity, 76%) and -30% (sensitivity, 85%; specificity, 73%). At least 30% limb fat is needed to be lost in HIV-infected patients for lipoatrophy to become clinically evident.

Efficacy and safety of switching from boosted lopinavir to boosted atazanavir in patients with virological suppression receiving a LPV/r-containing HAART: the ATAZIP study.

OBJECTIVES: To evaluate the efficacy and safety of switching from boosted lopinavir (LPV/r) to boosted atazanavir (ATV/r) in virologically suppressed HIV-1-infected patients versus continuing LPV/r. METHODS: Forty-eight weeks analysis of a randomized, open-label, noninferiority trial including patients with virological suppression (< or = 200 copies/mL for > or = 6 months) on LPV/r-containing triple highly active antiretroviral therapy. Patients (n = 248) were randomized 1:1 either to continue LPV/r twice a day (n = 127) or to switch to ATV/r every day (ATV/r; n = 121), with no change in nucleoside reverse transcriptase inhibitor backbone. Those known to have >4 protease inhibitor (PI)-associated mutations and/or who had failed >2 PI-containing regimens were excluded. RESULTS: Baseline characteristics were balanced. 30% harboured > or = 1 PI-associated mutation (10% harboured > or = 1 major mutation). Treatment failure at 48 weeks (primary end point) occurred in 20% (25 of 127) of the LPV/r arm and in 17% (21 of 121) of the ATV/r arm (difference -2.3%; 95% confidence interval: -12.0 to 8.0; P = 0.0018). Virological failure occurred in 7% (9 of 127) of the LPV/r arm and in 5% (6 of 121) of the ATV/r arm (difference -2.1%; 95% confidence interval: -8.7% to 4.2%, P < 0.0001 for noninferiorating). CD4 changes from baseline were similar in each arm (approximately 40 cells/mm). Adverse event rate leading to study drug discontinuation was 5% in both arms. Median fasting triglycerides and total cholesterol decreased significantly in the ATV/r arm (-53 and -19 mg/dL, respectively versus -4 and -4 mg/dL in the LPV/r arm; P < 0.001 in both comparisons). Alanine aminotransferase/aspartate aminotransferase hepatic abnormalities were similar in the 2 arms. CONCLUSIONS: Switching to ATV/r in virologically suppressed patients who were receiving a LPV/r-containing highly active antiretroviral therapy provided comparable (noninferior) efficacy and a safety profile with improved lipid parameters [ISRCTN24813210].

Less lipoatrophy and better lipid profile with abacavir as compared to stavudine: 96-week results of a randomized study.

OBJECTIVE: To assess lipoatrophy, other toxicities, and efficacy associated with abacavir as compared with stavudine in HIV-infected antiretroviral-naive patients. METHODS: This was a prospective, randomized, open trial, stratified by viral load and CD4 cell count, conducted January 2001 to July 2004. Two hundred thirty-seven adult patients with HIV infection initiating antiretroviral therapy were assigned to receive abacavir (n = 115) or stavudine (n = 122), both combined with lamivudine and efavirenz. The primary endpoint was the proportion of patients with lipoatrophy as assessed by physician and patient observation at 96 weeks. RESULTS: A lower proportion of patients assigned to abacavir developed clinical signs of lipoatrophy (4.8% vs. 38.3%; P < 0.001). These observations were confirmed by anthropometric data. Dual energy x-ray absorptiometry (DEXA) scans performed in 57 patients showed significantly greater total limb fat loss in the stavudine arm (-1579 vs. 913 g; P < 0.001). The lipid profile in abacavir patients presented more favorable changes in the levels of triglycerides (P = 0.03), high-density lipoprotein cholesterol (HDLc; P < 0.001), and apolipoprotein A1 (P < 0.001) as well as in the ratio between total cholesterol and HDLc (P = 0.005). Throughout the study, a higher proportion of patients in the stavudine group received lipid-lowering agents as compared to the abacavir group (17% vs. 4%; P = 0.002). Similar virologic and immunologic responses were observed. CONCLUSIONS: Assuming the limitations inherent to clinical assessment, this study shows a notably weaker association of abacavir with lipoatrophy than stavudine. DEXA scans and anthropometric measurements supported the clinical findings. In addition, the lipid changes that occurred were more favorable in patients receiving abacavir.

Substitution of nevirapine, efavirenz, or abacavir for protease inhibitors in patients with human immunodeficiency virus infection.

BACKGROUND: We assessed the strategy of substituting nevirapine, efavirenz, or abacavir for a protease inhibitor in patients infected with human immunodeficiency virus type 1 (HIV-1) in whom virologic suppression had been achieved. METHODS: We randomly assigned 460 adults who were taking two nucleoside reverse-transcriptase inhibitors and at least one protease inhibitor and whose plasma HIV-1 RNA levels had been less than 200 copies per milliliter for at least the previous six months to switch from the protease inhibitor to nevirapine (155 patients), efavirenz (156), or abacavir (149). The primary end point was death, progression to the acquired immunodeficiency syndrome, or an increase in HIV-1 RNA levels to 200 copies or more per milliliter. RESULTS: At 12 months, the Kaplan-Meier estimates of the likelihood of reaching the end point were 10 percent in the nevirapine group, 6 percent in the efavirenz group, and 13 percent in the abacavir group (P=0.10 according to an intention-to-treat analysis). HIV-1 RNA could be amplified in 21 of the 29 patients in whom virologic failure developed during treatment with study medication (72 percent), and resistance mutations to the study medication and to at least one of the nucleoside reverse-transcriptase inhibitors in the regimen that failed were detected in all but 1 of the 21 patients. Twenty-three of the 29 patients with virologic failure during treatment with study medication had received prior suboptimal therapy with nucleoside reverse-transcriptase inhibitors. Fewer patients in the abacavir group (6 percent) than in the nevirapine group (17 percent) or the efavirenz group (17 percent) discontinued the study medication because of adverse events (P=0.01). The proportion of patients with fasting lipid levels warranting therapeutic intervention decreased significantly in the abacavir group, but the prevalence of clinical lipodystrophy did not change significantly in the three groups. CONCLUSIONS: When therapy was switched from a protease inhibitor to nevirapine, efavirenz, or abacavir in patients with virologic suppression, there was a trend toward a higher rate of virologic failure among those given abacavir.

A randomized clinical trial comparing nelfinavir or nevirapine associated to zidovudine/lamivudine in HIV-infected naive patients (the Combine Study).

BACKGROUND: Non-nucleoside reverse transcriptase inhibitor-containing regimens may be a valid alternative to protease inhibitor-containing regimens for initial antiretroviral therapy, but to date few studies comparing these two strategies have been performed. OBJECTIVE: To evaluate the efficacy and safety of nelfinavir or nevirapine associated to zidovudine/lamivudine in HIV-infected naive patients. DESIGN: Randomized, open-label, multicentre trial. SETTING: Twelve centres in Spain (9) and Argentina (3). PATIENTS: One hundred and forty-two HIV-infected naive patients without AIDS. INTERVENTIONS: Patients received combivir (zidovudine 300 mg/lamivudine 150 mg, twice-daily) plus either nelfinavir (1250 mg) twice-daily (zidovudine/lamivudine/nelfinavir, n=70) or nevirapine (200 mg) twice-daily (zidovudine/lamivudine/nevirapine, n=72), and were followed for 12 months. The primary endpoint was the proportion of patients with a plasma HIV-1 RNA (pVL) of less than 200 copies/ml by PCR at 12 months. pVL of less than 20 copies/ml (PCR), changes in CD4 counts, clinical progression and adverse events were also evaluated. Efficacy was assessed using intent-to-treat (ITT) (missing=failure) and on-treatment analysis. RESULTS: At 12 months in the ITT analysis the proportion of patients with pVL below 200 copies/ml was 60% (95% CI 48.5-71.5) in the zidovudine/lamivudine/nelfinavir arm and 75% (95% CI 65-85) in the zidovudine/lamivudine/nevirapine arm (P=0.06), and the proportion below 20 copies/ml was 50% (95% CI 38.3-61.7) and 65% (95% CI 54.2-76.2), respectively (P=0.06). No differences were found when comparing the subgroup of patients with baseline pVL of more than 100,000 copies/ml. A gain of +173 and +162 CD4 cells/mm3, respectively, was observed. Zidovudine/lamivudine/nelfinavir was discontinued in 21% of patients, and zidovudine/lamivudine/nevirapine in 25%, due to toxicity (P>0.2). CONCLUSIONS: Our results suggest that zidovudine/lamivudine/nevirapine is at least as effective as zidovudine/lamivudine/nelfinavir as first-line therapy for HIV disease.