G. Penco

Dolutegravir in Antiretroviral-Experienced Patients With Raltegravir- and/or Elvitegravir-Resistant HIV-1: 24-Week Results of the Phase III VIKING-3 Study

Background.u2003The pilot phase IIb VIKING study suggested that dolutegravir (DTG), a human immunodeficiency virus (HIV) integrase inhibitor (INI), would be efficacious in INI-resistant patients at the 50 mg twice daily (BID) dose. Methods.u2003VIKING-3 is a single-arm, open-label phase III study in which therapy-experienced adults with INI-resistant virus received DTG 50 mg BID while continuing their failing regimen (without raltegravir or elvitegravir) through day 7, after which the regimen was optimized with ≥1 fully active drug and DTG continued. The primary efficacy endpoints were the mean change from baseline in plasma HIV-1 RNA at day 8 and the proportion of subjects with HIV-1 RNA <50 c/mL at week 24. Results.u2003Mean change in HIV-1 RNA at day 8 was −1.43 log10 c/mL, and 69% of subjects achieved <50 c/mL at week 24. Multivariate analyses demonstrated a strong association between baseline DTG susceptibility and response. Response was most reduced in subjects with Q148 + ≥2 resistance-associated mutations. DTG 50 mg BID had a low (3%) discontinuation rate due to adverse events, similar to INI-naive subjects receiving DTG 50 mg once daily. Conclusions.u2003DTG 50 mg BID–based therapy was effective in this highly treatment-experienced population with INI-resistant virus. Clinical Trials Registration.u2003www.clinicaltrials.gov (NCT01328041) and http://www.gsk-clinicalstudywww.gsk-clinicalstudyregister.com (112574).

Prevalence of transmitted HIV-1 drug resistance in HIV-1 infected patients in Italy: evolution over 12 years and predictors

OBJECTIVESnTransmitted HIV-1 drug resistance (TDR) can reduce the efficacy of first-line antiretroviral therapy.nnnPATIENTS AND METHODSnA retrospective analysis was performed to assess the prevalence and correlates of TDR in Italy over time. TDR was defined as the presence of at least one of the mutations present in the surveillance drug resistance mutation (SDRM) list.nnnRESULTSnAmong 1690 antiretroviral therapy-naive patients, the most frequent HIV subtypes were B (78.8%), CRF02_AG (5.6%) and C (3.6%). Overall, TDR was 15%. TDR was 17.3% in subtype B and 7.0% in non-B carriers (P < 0.001). TDR showed a slight, although not significant, decline (from 16.3% in 1996-2001 to 13.4% in 2006-07, P = 0.15); TDR declined for nucleoside reverse transcriptase inhibitors (from 13.1% to 8.2%, P = 0.003) but remained stable for protease inhibitors (from 3.7% to 2.5%, P = 0.12) and non-nucleoside reverse transcriptase inhibitors (from 3.7% to 5.8%). TDR to any drug was stable in B subtype and showed a decline trend in non-B. In multivariable analysis, F1 subtype or any non-B subtype, compared with B subtype, and higher HIV RNA were independent predictors of reduced odds of TDR.nnnCONCLUSIONSnPrevalence of TDR to nucleoside reverse transcriptase inhibitors seems to have declined in Italy over time. Increased prevalence of non-B subtypes partially justifies this phenomenon.

Evolution of transmitted HIV-1 drug resistance in HIV-1-infected patients in Italy from 2000 to 2010

Prevalence and predictors of transmitted drug resistance (TDR), defined as the presence of at least one WHO surveillance drug resistance mutation (SDRM), were investigated in antiretroviral-naïve HIV-1-infected patients, with a genotypic resistance test (GRT) performed ≤6 months before starting cART between 2000 and 2010. 3163 HIV-1 sequences were selected (69% subtype B). Overall, the prevalence of TDR was 12% (13.2% subtype B, 9% non-B). TDR significantly declined overall and for the single drug classes. Older age independently predicted increased odds of TDR, whereas a more recent GRT, a higher HIV-RNA and C vs. B subtype predicted lower odds of TDR.

Prevalence of HIV-1 integrase mutations related to resistance to dolutegravir in raltegravir naïve and pretreated patients.

The prevalence of HIV-1 integrase mutations related to resistance to the next-generation integrase inhibitor (INI), dolutegravir (DTG), was assessed in 440 INI-naïve subjects and in 120 patients failing a raltegravir (RTG)-containing regimen. Of the mutations selected by DTG in vitro, S153FY was not detected in any isolate while L101I and T124A were highly prevalent in both groups and significantly associated with non-B subtype. RTG-selected double and triple mutants, mostly the G140S/Q148H variant, were detected in only 32 (26.7%) RTG-treated patients. As L101I and T124A do not appear to exert any major effect in vivo and double and triple mutants resistant to DTG are infrequently selected by RTG, DTG can be effectively used in INI-naïve patients and may retain activity in many patients failing RTG.

Duration of first-line antiretroviral therapy with tenofovir and emtricitabine combined with atazanavir/ritonavir, efavirenz or lopinavir/ritonavir in the Italian ARCA cohort

OBJECTIVESnTo explore the durability of three first-line tenofovir/emtricitabine-based regimens in combination with atazanavir/ritonavir, efavirenz or lopinavir/ritonavir in HIV-1-infected patients.nnnPATIENTS AND METHODSnA retrospective, longitudinal, multicentre analysis of adult patients enrolled in the Antiretroviral Resistance Cohort Analysis (ARCA), a national prospective observational cohort of HIV-1-infected patients followed up at more than 100 clinical and laboratory units in Italy. Patients eligible were those starting first-line antiretroviral therapy between 1 June 2004 and 15 April 2011 and who were followed up for at least 6 months. The primary endpoint was durability, defined as the time from antiretroviral therapy initiation to first treatment modification. Time-dependent events were analysed by the Kaplan-Meier approach and the Cox proportional hazard model.nnnRESULTSnThere are 26,000 HIV-infected patients in the ARCA database, of whom 1654 met study inclusion criteria. Six hundred and thirty-nine (38.6%) received efavirenz, 321 (19.4%) received atazanavir/ritonavir and 694 (41.9%) received lopinavir/ritonavir as a first-line regimen. Over a total observation period of 88 months, equivalent to more than 2805 person-years of follow-up, 618 patients underwent treatment modification. Lopinavir/ritonavir, given twice daily, was associated with a higher discontinuation rate than efavirenz- and atazanavir-based regimens [hazard ratio (HR) 1.83, 95% confidence interval (CI) 1.56-2.15, P = 0.001]. Comparing the once-daily regimens, the rate of discontinuation of efavirenz was higher than that of atazanavir/ritonavir (HR 1.39, 95% CI 1.06-1.83, P = 0.016).nnnCONCLUSIONSnSignificant differences in treatment duration were observed among the three studied regimens. Once-daily regimens exhibited greater durability than the twice-daily regimen. Among the specific regimens examined, tenofovir/emtricitabine plus atazanavir/ritonavir showed the greatest durability.

Update on emergence of HIV-1 resistance to antiretroviral drug classes in an Italian national database: 2007-2009

We analysed trends of human immunodeficiency virus type 1 (HIV-1) drug resistance during 2007-2009 in the Italian national HIV drug resistance database ARCA. Prevalence of resistance in each year was examined on the basis of the presence of major International AIDS Society-2009 mutations. Predictors of resistance were analysed by multivariable logistic regression. Nine hundred and sixty-six patients were selected. Resistance to nucleoside reverse transcriptase inhibitors and protease inhibitors showed a significant decline with respect to previous surveys. Resistance to any class of drug and three drug classes remained stable. Independent predictors of three-class resistance were the number of treatment regimens experienced, prior suboptimal nucleoside reverse transcriptase inhibitor therapy and the current use of ritonavir-boosted protease inhibitors.

Factors associated with virological success with raltegravir-containing regimens and prevalence of raltegravir-resistance-associated mutations at failure in the ARCA database

Raltegravir (RAL) is the only licensed human immunodeficiency virus (HIV) integrase inhibitor. The factors associated with the virological response to RAL-containing regimens and the prevalence of integrase mutations associated with RAL failure deserve further investigation. From the Antiretroviral Resistance Cohort Analysis database, we selected triple-class-experienced subjects failing their current treatment with complete treatment history available. Selection criteria included HIV-RNA, CD4 count and HIV genotype within 3 months of RAL initiation. Factors associated with 24-week response were analysed; genotypic sensitivity scores (GSS) and weighted-GSS were evaluated. Virological response was achieved in 74.3% of 105 subjects. Mutations associated with RAL failure were detected in 12/24 subjects with an integrase genotype, with the prevalence of Q148H + G140S. Each extra unit of GSS (p 0.05, OR 2.62; 95% CI 1.00-6.87). was found to be a associated with response. Weighted-GSS had borderline statistical significance (p 0.063, OR 2.04; 95% CI 0.96-4.33) When stratifying for different cut-offs (<1 as reference, 1-1.49, ≥1.5), a borderline significant increase in the probability of response appeared for GSS ≥1.5 (p 0.053, OR 4.00; 95% CI 0.98-16.25). GSS ≥1 showed the highest sensitivity, 82.6%. Receiver operating characteristic curves depicted the widest area under the curve (0.663, p 0.054) of GSS ≥1. Unresponsiveness to RAL-containing regimens among triple-class-experienced subjects was low. The activity of the background regimen was strongly associated with response. Although few integrase genotypes were available at failure, half of these were without integrase resistance mutations. The substantial rate of RAL failure in the absence of known RAL-resistance mutations may be associated with adherence issues and this issue warrants further analysis in longer observations.

Vitamin D deficiency in HIV-infected patients: a systematic review

Advances in the diagnosis and management of human immunodeficiency virus (HIV) have resulted in a dramatic decrease in mortality in HIV-infected individuals (HIV+). The subsequent increase in life expectancy of HIV+ has led to the need to consider the long-term complications of the disease and its treatment. Abnormalities in vitamin D status and metabolism are increasingly recognized as a major concern in HIV infection. In the last 5 years a number of cross-sectional and prospective studies have suggested a high prevalence of vitamin D deficiency in HIV+. Although few case-control studies have been published, it has been suggested that the prevalence of hypovitaminosis D in HIV+ is higher than in the general population, and at least in part, is related to the course of the disease and/or the antiretroviral drugs used to treat the disease. An adequate vitamin D status is important not only for bone tissue, but also for the global health status of HIV+ individuals, since a growing body of evidence has demonstrated the detrimental effects of vitamin D deficiency on multiple health outcomes. Therefore, defini- tion of the size of the problem and identification of effective protocols for the prevention and management of vitamin D deficiency in HIV+ patients represent important steps in improving health status and reducing long-term chronic complications in individuals with HIV. Due to its immunomodulatory effects, vitamin D may also have implications in the progression of HIV infection. This systematic review was designed to determine the prevalence of vitamin D defi- ciency in HIV+ patients; to identify risk factors (related to the HIV infection or not) potentially associated with this condition; to describe the potential consequences of hypovitaminosis D on the course of the infection and the benefits of vitamin D repletion; and to make some sugges- tions about the future, considering the limitations of previous studies.

A prognostic model for estimating the time to virologic failure in HIV-1 infected patients undergoing a new combination antiretroviral therapy regimen

BackgroundHIV-1 genotypic susceptibility scores (GSSs) were proven to be significant prognostic factors of fixed time-point virologic outcomes after combination antiretroviral therapy (cART) switch/initiation. However, their relative-hazard for the time to virologic failure has not been thoroughly investigated, and an expert system that is able to predict how long a new cART regimen will remain effective has never been designed.MethodsWe analyzed patients of the Italian ARCA cohort starting a new cART from 1999 onwards either after virologic failure or as treatment-naïve. The time to virologic failure was the endpoint, from the 90th day after treatment start, defined as the first HIV-1 RNA > 400 copies/ml, censoring at last available HIV-1 RNA before treatment discontinuation. We assessed the relative hazard/importance of GSSs according to distinct interpretation systems (Rega, ANRS and HIVdb) and other covariates by means of Cox regression and random survival forests (RSF). Prediction models were validated via the bootstrap and c-index measure.ResultsThe dataset included 2337 regimens from 2182 patients, of which 733 were previously treatment-naïve. We observed 1067 virologic failures over 2820 persons-years. Multivariable analysis revealed that low GSSs of cART were independently associated with the hazard of a virologic failure, along with several other covariates. Evaluation of predictive performance yielded a modest ability of the Cox regression to predict the virologic endpoint (c-index≈0.70), while RSF showed a better performance (c-index≈0.73, p < 0.0001 vs. Cox regression). Variable importance according to RSF was concordant with the Cox hazards.ConclusionsGSSs of cART and several other covariates were investigated using linear and non-linear survival analysis. RSF models are a promising approach for the development of a reliable system that predicts time to virologic failure better than Cox regression. Such models might represent a significant improvement over the current methods for monitoring and optimization of cART.

Raltegravir-based therapy in a cohort of HIV/HCV co-infected individuals

The relationship between hepatic tolerance and hepatitis C virus (HCV) co-infection has not been extensively studied in clinical practice. We assessed the efficacy and safety of raltegravir-based therapy in an Italian cohort of HIV/HCV co-infected patients. One hundred and forty patients with HIV/HCV co-infection initiating raltegravir from SCOLTA project (Surveillance Cohort Long-Term Toxicity Antiretrovirals) were examined. Of them, 43 were women, with mean age of 45.4±6.4years; 65 (46%) had undetectable HIV-RNA<50copies/mL and 75 (54%) HIV-RNA≥50copies/mL. According to CDC classification, 49 (35%) were in stage C. Based on Fib4 score at the time of starting raltegravir, patients were classified in class I in 41 cases, class II in 68 and in class III in 31 cases. Globally, the Fib4 score slightly decreased during 24months follow-up, from 2.2 to a value of 1.8. Hepatic adverse events of any grade were observed in 67 patients, of which only 2 cases (3%) had severe liver toxicity (grade 3-4). Only one patient had to discontinue the therapy because of adverse events. According to univariate analysis, being in CDC stage C represented a risk for the development of liver toxicity, with a hazard ratio (HR) of 2.27 (95% CI 1.06-4.84, P=0.033). None of the other variables considered (age, sex, years since detection of HIV and HCV-RNA detectable, years of previous HIV therapy, concomitant therapy with PI or NRTI, CD4+ cell count, Fib4, and transaminases level at baseline) resulted statistically correlated to the outcome. In conclusion, raltegravir-based regimens can be safely used in HCV infected patients; in this study, the hepatic toxicity has been found to be more frequent in patients with an advanced HIV disease (CDC stage C), independently of HIV-RNA suppression at raltegravir initiation.