Mitochondrial Haplogroups and Weight Gain After Initiating ART in Patients With HIV.

We studied the association of mitochondrial DNA (mtDNA) haplogroups with weight and body mass index (BMI) gain at 96 weeks in 1019 treatment-naive persons with HIV (PWH) who initiated first-line antiretroviral therapy (ART) since 2014. The mean increase in weight and BMI over the study period was 2.90 kg and 0.98 kg/m2, respectively. We found a significant adjusted association between the major UK mtDNA haplogroup and lower weight and BMI increase at 96 weeks after ART initiation. Our findings reveal a potential role for mitochondrial genetics in the complex phenomenon of weight gain after initial ART in PWH.

Hepatocellular carcinoma risk in hepatitis C stage-3 fibrosis after sustained virological response with direct-acting antivirals.

BACKGROUND & AIMS: Patients with chronic hepatitis C and stage 3 fibrosis are thought to remain at risk of hepatocellular carcinoma after sustained virological response. We investigated this risk in a large cohort of patients with well-defined stage 3 fibrosis. METHODS: We performed a multicentre, ambispective, observational study of chronic hepatitis C patients with sustained virological response after treatment with direct-acting antivirals started between January and December 2015. Baseline stage 3 was defined in a two-step procedure: we selected patients with transient elastography values of 9.5-14.5 kPa and subsequently excluded those with nodular liver surface, splenomegaly, ascites or collaterals on imaging, thrombopenia or esophago-gastric varices. Patients were screened twice-yearly using ultrasound. RESULTS: The final sample comprised 506 patients (median age, 57.4 years; males, 59.9%; diabetes, 17.2%; overweight, 44.1%; genotype 3, 8.9%; HIV coinfection, 18.4%; altered liver values, 15.2%). Median follow-up was 33.7 (22.1-39.1) months. Five hepatocellular carcinomas and 1 cholangiocarcinoma were detected after a median of 29.4 months (95% CI: 26.8-39.3), with an incidence of 0.47/100 patients/year (95% CI: 0.17-1.01). In the multivariate analysis, only males older than 55 years had a significant higher risk (hazard ratio 7.2 [95% CI: 1.2-41.7; P = .029]) with an incidence of 1.1/100 patients/year (95% CI: 0.3-2.8). CONCLUSIONS: In a large, well-defined cohort of patients with baseline hepatitis C stage-3 fibrosis, the incidence of primary liver tumours was low after sustained virological response and far from the threshold for cost-effectiveness of screening, except in males older than 55 years.

Arsenate removal from aqueous solution by montmorillonite and organo-montmorillonite magnetic materials.

Magnetic-clay (MtMag) and magnetic-organoclay (O100MtMag) nanocomposites were synthesized, characterized and evaluated for arsenic adsorption. Batch arsenic adsorption experiments were performed varying pH conditions and initial As(V) concentration, while successive adsorption cycles were made in order to evaluate the materials reuse. The highest As(V) removal efficiency (9 ± 1 mg g-1 and 7.8 ± 0.8 mg g-1 for MtMag and O100MtMag, respectively) was found at pH 4.0, decreasing at neutral and alkaline conditions. From As(V) adsorption isotherm, two adsorption processes or two different surface sites were distinguished. Nanocomposites resulted composed by montmorillonite or organo-montmorillonite and magnetite as the principal iron oxide, with saturation magnetization of 8.5 ± 0.5 Am2 Kg-1 (MtMag) and 20.3 ± 0.5 Am2 Kg-1 (O100MtMag). Thus, both materials could be separated and recovered from aqueous solutions using external magnetic fields. Both materials allowed achieving arsenic concentrations lower than the World Health Organization (WHO) recommended concentration limit after two consecutive adsorption cycles (2.25 and 4.5 µg L-1 for MtMag and O100MtMag, respectively).

Eradication of hepatitis C virus and non-liver-related non-acquired immune deficiency syndrome-related events in human immunodeficiency virus/hepatitis C virus coinfection.

We assessed non-liver-related non-acquired immunodeficiency syndrome (AIDS)-related (NLR-NAR) events and mortality in a cohort of human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients treated with interferon (IFN) and ribavirin (RBV), between 2000 and 2008. The censoring date was May 31, 2014. Cox regression analysis was performed to assess the adjusted hazard rate (HR) of overall death in responders and nonresponders. Fine and Gray regression analysis was conducted to determine the adjusted subhazard rate (sHR) of NLR deaths and NLR-NAR events considering death as the competing risk. The NLR-NAR events analyzed included diabetes mellitus, chronic renal failure, cardiovascular events, NLR-NAR cancer, bone events, and non-AIDS-related infections. The variables for adjustment were age, sex, past AIDS, HIV transmission category, nadir CD4+ T-cell count, antiretroviral therapy, HIV RNA, liver fibrosis, HCV genotype, and exposure to specific anti-HIV drugs. Of the 1,625 patients included, 592 (36%) had a sustained viral response (SVR). After a median 5-year follow-up, SVR was found to be associated with a significant decrease in the hazard of diabetes mellitus (sHR, 0.57; 95% confidence interval [CI], 0.35-0.93; P = 0.024) and decline in the hazard of chronic renal failure close to the threshold of significance (sHR, 0.43; 95% CI, 0.17-1.09; P = 0.075). CONCLUSION: Our data suggest that eradication of HCV in coinfected patients is associated not only with a reduction in the frequency of death, HIV progression, and liver-related events, but also with a reduced hazard of diabetes mellitus and possibly of chronic renal failure. These findings argue for the prescription of HCV therapy in coinfected patients regardless of fibrosis stage. (Hepatology 2017;66:344-356).

Rilpivirine Activates STAT1 in Non-Parenchymal Cells to Regulate Liver Injury in People Living with HIV and MASLD.

Liver fibrosis is a key determinant of the progression of metabolic dysfunction-associated steatotic liver disease (MASLD). Its increasing prevalence and a lack of effective treatments make it a major health problem worldwide, particularly in people living with HIV, among whom the prevalence of advanced fibrosis is higher. We have published preclinical data showing that Rilpivirine (RPV), a widely used anti-HIV drug, selectively triggers hepatic stellate cell (HSC) inactivation and apoptosis through signal transducer and activator of transcription (STAT)1-mediated pathways, effects that clearly attenuate liver fibrosis and promote regeneration. We performed a retrospective, cross-sectional study of RPV-induced effects on steatosis, inflammation, and fibrosis in liver biopsies from well-controlled HIV-infected subjects diagnosed with MASLD. Patients on RPV exhibited similar levels of HIV-related parameters to those not receiving this drug, while showing a tendency toward improved liver function and lipid profile, as well as an enhanced activation of STAT1 in hepatic non-parenchymal cells in those with identified liver injury. This protective effect, promoting STAT1-dependent HSC inactivation, was observed at different stages of MASLD. Our results suggest that RPV-based therapy is especially indicated in HIV-infected patients with MASLD-derived liver injury and highlight the potential of RPV as a new therapeutic strategy for liver diseases.

Clinical effects of viral relapse after interferon plus ribavirin in patients co-infected with human immunodeficiency virus and hepatitis C virus.

BACKGROUND & AIMS: Sustained viral response (SVR) after therapy with interferon-ribavirin (IF-RB) reduces liver-related (LR) complications and mortality in HIV/HCV-co-infected patients. Here, we assess the impact of end-of-treatment response with subsequent relapse (REL) on LR events (LR death, liver decompensation, hepatocellular carcinoma, or liver transplantation), and liver stiffness (LS) by transient elastography. METHODS: We analyzed the GESIDA 3603 Cohort (HIV/HCV-co-infected patients treated with IF-RB in 19 centers in Spain). Response to IF-RB was categorized as SVR, REL, and no response (NR). The study started when IF-RB was stopped and ended at death or the last follow-up visit. Multivariate regression analyses were adjusted for age, sex, HIV category of transmission, CDC clinical category, nadir CD4+ cell count, HCV genotype, HCV-RNA viral load, and liver fibrosis. RESULTS: Of 1599 patients included, response was categorized as NR in 765, REL in 250 and SVR in 584. Median follow-up was more than 4 years in each group. Taking the group of patients with NR as reference, we found that the adjusted hazard ratios (95% confidence interval) of liver-related events (liver-related death, liver decompensation, hepatocellular carcinoma, liver transplantation) for patients with REL and for patients with SVR were 0.17 (0.05; 0.50) and 0.03 (0; 0.20), respectively. We also found that SVR was followed by less liver stiffness than both REL and NR. However, REL was associated with less liver stiffness than NR. CONCLUSIONS: Best outcomes were achieved with an SVR. However, REL was associated with less LR mortality, decompensation, and liver stiffness than NR.

Paracetamol and Ibuprofen Removal from Aqueous Phase Using a Ceramic-Derived Activated Carbon.

Emerging pollutants, including pharmaceuticals and personal care products, have been detected in surface and groundwaters. The adsorption of paracetamol and ibuprofen, two widespread drugs, has been studied in aqueous medium, using a ceramic-derived carbon (CeDC) and a commercial activated carbon (CoAC). CeDC yielded a BET surface area of 895 m2 g-1, a bimodal pore size distribution (13.2 and 35 nm) and a total pore volume of 1.99 cm3 g-1. CoAC had an approximate surface area of 1000 m2 g-1, a homogeneous pore size distribution and a total pore volume of 0.42 cm3 g-1. Kinetic and equilibrium tests were carried out in batch systems to study the materials' sorption performances. The intraparticle diffusion model best fitted the experimental kinetic data. The maximum ibuprofen sorption capacities were 120 mg g-1 and 133 mg g-1 for CoAC and CeDC, respectively, whereas no major differences on the maximum paracetamol sorption capacities (qm) were observed among the sorbents (150-159 mg g-1). Therefore, CeDC, synthesized easily from a ceramic composite, improved time and sorption capacity of paracetamol and ibuprofen compared to the commercial activated carbon, indicating the potential of the developed carbon as an emerging pollutant sorbent material.

Sustained virological response to interferon plus ribavirin reduces non-liver-related mortality in patients coinfected with HIV and Hepatitis C virus.

BACKGROUND: Sustained virological response (SVR) after therapy with interferon plus ribavirin reduces liver-related complications and mortality in patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). We assessed the effect of SVR on HIV progression and mortality not related to liver disease. METHODS: An observational cohort study including consecutive HIV/HCV-coinfected patients treated with interferon plus ribavirin between 2000 and 2008 in 19 centers in Spain. RESULTS: Of 1599 patients, 626 (39%) had an SVR. After a median follow-up of approximately 5 years, we confirmed that failure to achieve an SVR was associated with an increased risk of liver-related events and liver-related death. We also observed higher rates of the following events in nonresponders than in responders: AIDS-defining conditions (rate per 100 person years, 0.84 [95% confidence interval (CI), .59-1.10] vs 0.29 [.10-.48]; P= .003), non-liver-related deaths (0.65 [.42-.87] vs 0.16 [.02-.30]; P = .002), and non-liver-related, non-AIDS-related deaths (0.55 [.34-.75] vs 0.16 [.02-.30]; P = .002). Cox regression analysis showed that the adjusted hazard ratios of new AIDS-defining conditions, non-liver-related deaths, and non-liver-related, non-AIDS-related deaths for nonresponders compared with responders were 1.90 (95% CI, .89-4.10; P = .095), 3.19 (1.21-8.40; P = .019), and 2.85 (1.07-7.60; P = .036), respectively. CONCLUSIONS: Our findings suggest that eradication of HCV after therapy with interferon plus ribavirin in HIV/HCV-coinfected patients is associated not only with a reduction in liver-related events but also with a reduction in HIV progression and mortality not related to liver disease.

Plasma IP-10 and IL-6 are linked to Child-Pugh B cirrhosis in patients with advanced HCV-related cirrhosis: a cross-sectional study.

We aimed to evaluate the association of plasma biomarkers linked to inflammation (bacterial translocation, inflammatory response, and endothelial dysfunction), coagulopathy, and angiogenesis with the severity of liver cirrhosis (assessed by the Child-Pugh-Turcotte score, CTP) and Child-Pugh B cirrhosis (CTP 7-9) in patients with advanced hepatitis C virus (HCV)-related cirrhosis. We carried out a cross-sectional study in 97 patients with advanced HCV-related cirrhosis (32 HCV-monoinfected and 65 HIV/HCV-coinfected). Plasma biomarkers were measured by ProcartaPlex multiplex immunoassays. The outcome variable was the CTP score and the Child-Pugh B cirrhosis (CTP 7-9). HIV/HCV-coinfected patients and HCV-monoinfected patients with advanced HCV-related cirrhosis had near-equivalent values of plasma biomarkers. Higher values of plasma biomarkers linked to an inflammatory response (IP-10, IL-8, IL-6, and OPG), endothelial dysfunction (sVCAM-1 and sICAM-1), and coagulopathy (D-dimer) were related to higher CTP values. The most significant biomarkers to detect the presence of Child-Pugh B cirrhosis (CTP 7-9) were IP-10 (p-value= 0.008) and IL-6 (p-value=0.002). The AUC-ROC values of IP-10, IL-6, and both biomarkers combined (IP-10+IL-6) were 0.78, 0.88, and 0.96, respectively. In conclusion, HIV infection does not appear to have a significant impact on the analyzed plasma biomarkers in patients with advanced HCV-related cirrhosis. However, plasma biomarkers linked to inflammation (inflammatory response and endothelial dysfunction) were related to the severity of liver cirrhosis (CTP score), mainly IP-10 and IL-6, which discriminated patients with Child-Pugh B concerning Child-Pugh A.

Reinfection by hepatitis C virus following effective all-oral direct-acting antiviral drug therapy in HIV/hepatitis C virus coinfected individuals.

OBJECTIVES: We analysed hepatitis C virus (HCV) reinfection among participants in a prospective registry of HIV/HCV-coinfected patients treated with all-oral direct-acting antiretroviral (DAA)-based therapy in the region of Madrid. DESIGN: An observational cohort study. METHODS: The study period started on the date sustained viral response (SVR) was confirmed. The censoring date was 31 December 2017. SVR was defined as negative HCV-RNA 12 weeks after completion of treatment. Reinfection was defined as a positive HCV-RNA test result after achievement of SVR. RESULTS: Reinfections were detected in 17 of 2359 HIV/HCV-coinfected patients (0.72%) overall, in 12 out of 177 (6.78%) MSM and in five out of 1459 (0.34%) people who inject drugs (PWID). The incidence of reinfection [95% confidence interval (95% CI)] per 100 person-years was 0.48 (0.30-0.77) overall, 5.93 (3.37-10.44) for MSM and 0.21 (0.09-0.52) for PWID. Reinfections were detected a median of 15 weeks (interquartile range 13-26) after SVR. In 10 (58.82%) patients, the reinfection was caused by a different HCV genotype. All 12 MSM with reinfection acknowledged unprotected anal intercourse with several partners, seven used chemsex, six reported fisting and four practiced slamming. A concomitant STI was detected in five patients. Four IDU with reinfection reported injecting drugs following SVR. CONCLUSION: HCV reinfection is a matter of concern in HIV-positive MSM treated with all-oral DAA therapy in the region of Madrid. Our data suggest that prevention strategies and frequent testing with HCV-RNA should be applied following SVR in MSM who engage in high-risk practices.

Brief Report: Differential Effects of Tenofovir, Abacavir, Emtricitabine, and Darunavir on Telomerase Activity In Vitro.

In vitro, tenofovir and abacavir induced a significant dose-dependent inhibition of telomerase activity at therapeutic concentrations in peripheral blood mononuclear cells of healthy subjects. Median inhibition of telomerase activity by tenofovir at 0.5 and 1 µM was 29% [Interquartile range (IQR) 29%-34%, P = 0.042] and 28% (IQR 28%-41%, P = 0.042), respectively. Abacavir inhibition was 12% (IQR 9%-13%, P = 0.043) at 3 µM and 14% (IQR 10%-29%, P = 0.043) at 10 µM. Tenofovir and abacavir did not change human telomerase reverse transcriptase (hTERT) levels or mRNA levels of other telomerase complex genes. Exposure to emtricitabine or darunavir did not affect telomerase activity, hTERT protein levels, or mRNA levels of telomerase/shelterin genes.

Impact of Antiretroviral Treatment Containing Tenofovir Difumarate on the Telomere Length of Aviremic HIV-Infected Patients.

OBJECTIVE: To evaluate the in vivo relevance of the inhibitory effect of tenofovir on telomerase activity observed in vitro. DESIGN: Cross-sectional study of HIV-infected patients with suppressed virological replication (HIV RNA <50 copies/mL for more than 1 year). METHODS: Telomere length in whole blood was measured by quantitative real-time polymerase chain reaction. We performed a multivariate analysis to elucidate variables associated with telomere length and also evaluated the association between telomere length and use of tenofovir difumarate (TDF) adjusted by significant confounders. RESULTS: 200 patients included, 72% men, median age 49 (IQR 45-54.5), 103 with exposure to a TDF containing antiretroviral treatment (ART) regimen (69.9% for more than 5 years) and 97 never exposed to a TDF containing ART regimen. In the multivariate analysis, significant predictors of shorter telomere length were older age (P = 0.008), parental age at birth (P = 0.038), white race (P = 0.048), and longer time of known HIV infection (10-20 and ≥20 years compared with <10 years, P = 0.003 and P = 0.056, respectively). There was no association between TDF exposure and telomere length after adjusting for possible confounding factors (age, parental age at birth, race, and time of HIV infection). Total time receiving ART and duration of treatment with nucleoside reverse transcriptase inhibitors were associated with shorter telomere length, but these associations were explained by time of known HIV infection. CONCLUSIONS: Our data do not suggest that telomerase activity inhibition caused by TDF in vitro leads to telomere shortening in peripheral blood of HIV-infected patients.

Prognostic Value of Transient Elastography in Human Immunodeficiency Virus-Infected Patients With Chronic Hepatitis C.

BACKGROUND: Our objective was to study the prognostic value of liver stiffness (LS) in HIV-infected patients with chronic hepatitis C (CHC). METHODS: We analyzed HIV-infected patients with compensated CHC and at least 1 determination of LS. The primary outcome was the occurrence of liver-related events (LRE), namely, decompensation or hepatocellular carcinoma, whichever occurred first. We selected patients without sustained viral response (SVR) or end-of-treatment response (ETR) during follow-up and allocated them to an estimation cohort (EC) and a validation cohort (VC). RESULTS: The study population comprised 1292 patients. After a median follow-up of 5.8 years, 90 patients experienced LRE and 73 died. In the subgroup of 957 patients without SVR or ETR, the area under the receiver operating characteristic curves (AUROCs) (95% confidence interval [CI]) of LS for prediction of LRE in the EC (n = 634) and the VC (n = 323) were 0.87 and 0.88, respectively. The best cutoff value of LS to rule out LRE in the EC was 12 kPa, with a negative predictive value of 98.3% in the EC and 98.2% in the VC. Per each 1 kPa and 5 kPa increase above 12 kPa, the hazard ratio of LRE (taking into account death as a competing risk) was 1.07 (95% CI, 1.05-1.08) and 1.38 (95% CI, 1.31-1.46), respectively. CONCLUSIONS: Liver stiffness is very accurate for predicting LRE in coinfected patients. Patients with an LS <12 kPa had a 98% probability of not developing LRE after a median follow-up of almost 6 years. Above the 12-kPa cutoff, the hazard of LRE increases proportionally with LS.

The natural history of liver cirrhosis in HIV-hepatitis C virus-coinfected patients.

OBJECTIVE: To provide detailed information about the natural history of HIV-hepatitis C virus (HCV)-coinfected patients with cirrhosis. METHODS: Prospective cohort including 340 HIV-HCV-coinfected patients with compensated (n = 248) or decompensated (n = 92) cirrhosis. We evaluated predictors of survival and of first hepatic decompensation. RESULTS: The mortality rate for patients with decompensated and compensated cirrhosis was 27.14 deaths per 100 person-years [95% confidence interval (CI) 18.93-35.35] and 3.98 deaths per 100 person-years (95% CI 2.42-5.54), respectively. Rate of first hepatic decompensation in patients with compensated cirrhosis was 4.62 per 100 persons-years (95% CI 2.91-6.33). In the complete cohort, permanent HAART interruption during follow-up, CD4 cell count nadir and baseline Child-Pugh score (CPS) B or C were significantly associated with shorter survival. In patients with compensated cirrhosis factors significantly associated with decreased survival were having the first hepatic decompensation during follow-up, permanent HAART discontinuation, and CPS B and C at baseline. For patients with compensated cirrhosis, time since diagnosis of HCV infection, CPS B and C and permanent HAART discontinuation were significantly associated with the risk of first hepatic decompensation. Sustained viral response to anti-HCV therapy was not independently associated with better survival in patients with compensated cirrhosis. CONCLUSION: HIV-HCV-coinfected patients with cirrhosis have a relatively good 3-year survival (87%). In contrast, 2-year survival of patients with decompensated liver cirrhosis is only 50%. Three-year survival was mostly impacted by liver-related factors and HAART maintenance.

HAART is associated with lower hepatic necroinflammatory activity in HIV-hepatitis C virus-coinfected patients with CD4 cell count of more than 350 cells/microl at the time of liver biopsy.

OBJECTIVE: To evaluate the impact of HAART on the liver damage of HIV-hepatitis C virus (HCV)-coinfected patients with relatively preserved immune status. DESIGN: Cross-sectional study of liver biopsies. METHODS: HIV-HCV-coinfected patients who underwent liver biopsies and had a CD4 cell count of at least 350 cells/microl at the time of liver biopsy were included. Exclusion criteria included positive hepatitis B surface antigen and prior anti-HCV therapy. Necroinflammatory activity and fibrosis was scored by the Scheuer fibrosis staging system. Steatosis was scored according to the percentage of hepatocytes affected. Logistic regression analysis was used to assess determinants of necroinflammatory activity of at least 3. RESULTS: One hundred and nineteen HIV-HCV coinfected patients were included. In the univariate analysis, alcohol abuse, serum alanine aminotransferase levels, steatosis and a high fibrosis score were significantly associated with higher necroinflammatory activity. In the multivariate analysis, a high level of alanine aminotransferase, advanced fibrosis and absence of HAART were associated with higher necroinflammatory activity. CONCLUSION: Use of HAART was associated with lower levels of necroinflammatory activity. Necroinflammatory activity was strongly associated with higher fibrosis scores. These results suggest that HAART might decrease hepatitis C activity in HIV-HCV-coinfected patients with CD4 cell count of more than 350 cells/microl.

Lopinavir-ritonavir monotherapy versus lopinavir-ritonavir and 2 nucleosides for maintenance therapy of HIV: 96-week analysis.

BACKGROUND: The OK04 trial has shown that 48 weeks of lopinavir-ritonavir monotherapy with reintroduction of nucleosides as needed was noninferior to continuation of triple therapy with 2 nucleosides and lopinavir-ritonavir in patients with prior stable suppression. However, it is still uncertain if this experimental strategy can maintain suppression in the long term. METHODS: Patients entered this noninferiority trial (upper limit 95% confidence interval: +12%) with no history of virological failure while receiving a protease inhibitor and receiving 2 nucleosides plus lopinavir/ritonavir, with HIV RNA <50 copies per milliliter for more than 6 months. Primary end point was percent of patients without therapeutic failure, defined as confirmed HIV RNA >500 copies per milliliter with exclusion of monotherapy patients who resuppressed to <50 copies per milliliter after resuming baseline nucleosides, or loss to follow-up, or change of randomized therapy other than reinduction. RESULTS: Through 96 weeks, percentage of patient without therapeutic failure was 87% (monotherapy, n = 100) vs. 78% (triple therapy, n = 98; 95% confidence interval: -20% to +1.2%). Percentage with HIV RNA <50 copies per milliliter (intention to treat, missing = failure, reinduction = failure): 77% (monotherapy) vs. 78% (triple therapy). Low-level viral rebound was more frequent in the monotherapy group. Twelve patients in the monotherapy group (12%) needed reinduction with nucleosides. Discontinuations due to adverse events were significantly more frequent in the triple therapy group (8%) than in the monotherapy group (0%); P = 0.003. CONCLUSIONS: At 96-week lopinavir/ritonavir monotherapy with reintroduction of nucleosides as needed was noninferior to continuation of triple therapy. Incidence of adverse events leading to treatment discontinuation was significantly lower with monotherapy. (ClinicalTrials.gov number, NCT00114933).

Lopinavir/ritonavir as single-drug therapy for maintenance of HIV-1 viral suppression: 48-week results of a randomized, controlled, open-label, proof-of-concept pilot clinical trial (OK Study).

OBJECTIVE: This study evaluated maintenance with lopinavir/ritonavir monotherapy vs. continuing lopinavir/ritonavir and 2 nucleosides in HIV-infected patients with suppressed HIV replication. DESIGN: Randomized, controlled, open-label, multicenter, pilot clinical trial. METHODS: Adult patients were eligible if they had no history of virologic failure while receiving a protease inhibitor, were receiving 2 nucleosides + lopinavir/ritonavir (400/100 mg b.i.d.) for >1 month and had maintained serum HIV RNA <50 copies/mL for >6 months prior to enrollment. RESULTS: Forty-two patients were randomly assigned 1:1 to continue or stop the nucleosides. At baseline there were no significant differences between groups in median CD4 cells/muL (baseline or nadir), pre-HAART (highly active antiretroviral therapy) HIV log10 viremia, or time with HIV RNA <50 copies/mL prior to enrollment. After 48 weeks of follow-up, percentage of patients remaining at <50 HIV RNA copies/mL (intention to treat, M = F) was 81% for the monotherapy group (95% CI: 64% to 98%) vs. 95% for the triple-therapy group (95% CI: 86% to 100%); P = 0.34. Patients in whom monotherapy failed had significantly worse adherence than patients who remained virally suppressed on monotherapy. Monotherapy failures did not show primary resistance mutations in the protease gene and were successfully reinduced with prerandomization nucleosides. Mean change in CD4 cells/microL: +70 (monotherapy) and +8 (triple) (P = 0.27). Mean serum fasting lipids remained stable in both groups. No serious adverse events were observed. CONCLUSION: Most of the patients maintained with lopinavir/ritonavir monotherapy remain with undetectable viral load after 48 weeks. Failures of lopinavir/ritonavir monotherapy were not associated with the development of primary resistance mutations in the protease gene and could be successfully reinduced adding back prior nucleosides.