Stefano Vella

Changing patterns of mortality across Europe in patients infected with HIV-1

BACKGROUND The introduction of combination antiretroviral therapy and protease inhibitors has led to reports of falling mortality rates among people infected with HIV-1. We examined the change in these mortality rates of HIV-1-infected patients across Europe during 1994-98, and assessed the extent to which changes can be explained by the use of new therapeutic regimens. METHODS We analysed data from EuroSIDA, which is a prospective, observational, European, multicentre cohort of 4270 HIV-1-infected patients. We compared death rates in each 6 month period from September, 1994, to March, 1998. FINDINGS By March, 1998, 1215 patients had died. The mortality rate from March to September, 1995, was 23.3 deaths per 100 person-years of follow-up (95% CI 20.6-26.0), and fell to 4.1 per 100 person-years of follow-up (2.3-5.9) between September, 1997, and March, 1998. From March to September, 1997, the death rate was 65.4 per 100 person-years of follow-up for those on no treatment, 7.5 per 100 person-years of follow-up for patients on dual therapy, and 3.4 per 100 person-years of follow-up for patients on triple-combination therapy. Compared with patients who were followed up from September, 1994, to March, 1995, patients seen between September, 1997, and March, 1998, had a relative hazard of death of 0.16 (0.08-0.32), which rose to 0.90 (0.50-1.64) after adjustment for treatment. INTERPRETATION Death rates across Europe among patients infected with HIV-1 have been falling since September, 1995, and at the beginning of 1998 were less than a fifth of their previous level. A large proportion of the reduction in mortality could be explained by new treatments or combinations of treatments.

Hepatitis B and HIV: prevalence, AIDS progression, response to highly active antiretroviral therapy and increased mortality in the EuroSIDA cohort

Background: Whether hepatitis B (HBV) coinfection affects outcome in HIV-1-infected patients remains unclear. Objective: To assess the prevalence of HBV (assessed as HBsAg) coinfection and its possible impact on progression to AIDS, all-cause deaths, liver-related deaths and response to highly active antiretroviral therapy (HAART) in the EuroSIDA cohort. Methods: Data on 9802 patients in 72 European HIV centres were analysed. Incidence rates of AIDS, global mortality and liver-related mortality, time to 25% CD4 cell count increase and time to viral load < 400 copies/ml after starting HAART were calculated and compared between HBsAg-positive and HBsAg-negative patients. Results: HBsAg was found in 498 (8.7%) patients. The incidence of new AIDS diagnosis was similar in HBsAg-positive and HBsAg-negative patients (3.3 and 3.4/100 person-years, respectively) even after adjustment for potential confounders: the incidence rate ratio (IRR) was 0.94 [95% confidence interval (CI), 0.74–1.19; P = 0.61]. The incidences of all-cause and liver-related mortalities were significantly higher in HBsAg-positive subjects (3.7 and 0.7/100 person-years, respectively) compared with HBsAg-negative subjects (2.6 and 0.2/100 person-years, respectively). The adjusted IRR values were 1.53 for global (95% CI, 1.23–1.90; P = 0.0001) and 3.58 for liver-related (95% CI, 2.09–6.16; P < 0.0001) mortality. HBsAg status did not influence viral or immunological responses among the 1679 patients starting HAART. Conclusions: The prevalence of HBV coinfection was 9% in the EuroSIDA cohort. Chronic HBV infection significantly increased liver-related mortality in HIV-1-infected patients but did not impact on progression to AIDS or on viral and immunological responses to HAART.

Changing incidence of central nervous system diseases in the EuroSIDA cohort

A drastic decrease in incidence has been observed for most human immunodeficiency virus (HIV)–related opportunistic manifestations after use of highly active antiretroviral therapy (HAART). We assessed the trend of incidence of central nervous system (CNS) diseases in a prospective multicenter observational study involving 9,803 patients across Europe in the period 1994 to 2002 and analyzed patient and treatment variables associated with these conditions. Overall, 568 patients (5.8%) received a diagnosis of a new CNS disease. Incidence decreased significantly from 5.9 per 100 person‐year in 1994 to 0.5 in 2002. Overall, the decrease was 40% per calendar year, and it was similar to that of non‐CNS diseases and less evident after year 1998. In multivariable models, low CD4 cell count and high plasma viral load, but not HAART or calendar year, were significantly associated with risk to develop CNS disease, indicating that the effect of HAART was likely mediated by both improved immunological conditions and inhibition of viral replication. In contrast, use of nucleoside reverse transcriptase inhibitors, irrespective of use of protease inhibitors or non‐nucleoside reverse transcriptase inhibitors, appeared to protect specifically against acquired immunodeficiency disease syndrome dementia complex, suggesting that, in this condition, therapy might have a direct, additive effect in the CNS.

Barriers to a cure for HIV: new ways to target and eradicate HIV-1 reservoirs

Antiretroviral therapy for HIV infection needs lifelong access and strict adherence to regimens that are both expensive and associated with toxic effects. A curative intervention will be needed to fully stop the epidemic. The failure to eradicate HIV infection during long-term antiretroviral therapy shows the intrinsic stability of the viral genome in latently infected CD4T cells and other cells, and possibly a sustained low-level viral replication. Heterogeneity in latently infected cell populations and homoeostatic proliferation of infected cells might affect the dynamics of virus production and persistence. Despite potent antiretroviral therapy, chronic immune activation, inflammation, and immune dysfunction persist, and are likely to have important effects on the size and distribution of the viral reservoir. The inability of the immune system to recognise cells harbouring latent virus and to eliminate cells actively producing virus is the biggest challenge to finding a cure. We look at new approaches to unravelling the complex virus-host interactions that lead to persistent infection and latency, and discuss the rationale for combination of novel treatment strategies with available antiretroviral treatment options to cure HIV.

High exposure to nevirapine in plasma is associated with an improved virological response in HIV-1-infected individuals.

ObjectiveTo explore relationships between exposure to nevirapine and the virological response in HIV-1-infected individuals participating in the INCAS trial. MethodsThe elimination rate constant of plasma HIV-1 RNA (k) was calculated during the first 2 weeks of treatment with nevirapine, zidovudine and didanosine in 51 antiretroviral-naive HIV-1-infected patients. The relationships between the value of k, the time to reach an undetectable HIV-1 RNA concentration in plasma (< 20 copies/ml) and the success of therapy after 52 weeks of treatment as dependent variables and the exposure to nevirapine, baseline HIV-1 RNA and baseline CD4 cell count as independent variables, were explored using linear regression analyses, proportional hazard models and logistic analyses, respectively. ResultsThe value of k for HIV-1 RNA in plasma was positively and significantly associated with the mean plasma nevirapine concentration during the first 2 weeks of therapy (P = 0.011) and the baseline HIV-1 RNA (P = 0.008). Patients with a higher exposure to nevirapine reached undetectable levels of HIV-1 RNA in plasma more rapidly (P = 0.03). From 12 weeks on, the median nevirapine plasma concentration was significantly correlated with success of therapy after 52 weeks (P < 0.02). ConclusionsA high exposure to nevirapine (in a twice daily regimen) is significantly associated with improved virological response in the short as well as in the long term. These findings suggest that optimization of nevirapine concentration might be used as a tool to improve virological outcome in (antiretroviral-naive) patients treated with nevirapine.

Factors influencing medication adherence beliefs and self-efficacy in persons naive to antiretroviral therapy: a multicenter, cross-sectional study.

It is widely recognized that adherence to antiretroviral therapy is critical to long-term treatment success, yet rates of adherence to antiretroviral medications are frequently subtherapeutic. Beliefs about antiretroviral therapy and psychosocial characteristics of HIV-positive persons naive to therapy may influence early experience with antiretroviral medication adherence and therefore could be important when designing programs to improve adherence to antiretroviral therapy. As part of a multicenter AIDS Clinical Trial Group (ACTG 384) study, 980 antiretroviral-naive subjects (82% male, 47% White, median age 36 years, and median CD4 cell count 278 cells/mm3) completed a self-administered questionnaire prior to random treatment assignment of initial antiretroviral medications. Measures of symptom distress, general health and well-being, and personal and situational factors including demographic characteristics, social support, self-efficacy, depression, stress, and current adherence to (nonantiretroviral) medications were recorded. Associations among variables were explored using correlation and regression analyses. Beliefs about the importance of antiretroviral adherence and ability to take antiretroviral medications as directed (adherence self-efficacy) were generally positive. Fifty-six percent of the participants were “extremely sure” of their ability to take all medications as directed and 48% were “extremely sure” that antiretroviral nonadherence would cause resistance, but only 37% were as sure that antiretroviral therapy would benefit their health. Less-positive beliefs about antiretroviral therapy adherence were associated with greater stress, depression, and symptom distress. More-positive beliefs about antiretroviral therapy adherence were associated with better scores on health perception, functional health, social–emotional–cognitive function, social support, role function, younger age, and higher education (r values = 0.09–0.24, all p < .001). Among the subset of 325 participants reporting current use of medications (nonantiretrovirals) during the prior month, depression was the strongest correlate of nonadherence (r = 0.33, p < .001). The most common reasons for nonadherence to the medications were “simply forgot” (33%), “away from home” (27%), and “busy” (26%). In conclusion, in a large, multicenter survey, personal and situational factors, such as depression, stress, and lower education, were associated with less certainty about the potential for antiretroviral therapy effectiveness and ones perceived ability to adhere to therapy. Findings from these analyses suggest a role for baseline screening for adherence predictors and focused interventions to address modifiable factors placing persons at high risk for poor adherence prior to antiretroviral treatment initiation

The relationship between ritonavir plasma levels and side-effects: implications for therapeutic drug monitoring

OBJECTIVES To assess whether the neurological or gastrointestinal adverse effects of ritonavir correlate with parameters of ritonavir systemic exposure. METHODS Peak (Cmax) and trough (Cmin) ritonavir plasma levels were compared in 11 patients experiencing side-effects (group A) versus 10 patients without side-effects (group B). Ritonavir was administered with the following escalation dosing scheme: 300, 400, 500 mg twice a day for 3, 4, and 5 days, respectively, then the full dose of 600 mg twice a day. Blood sampling was done in group A within 24 h of the occurrence of side-effects and in group B after at least 3 days of the full dosage regimen. RESULTS Both Cmax and Cmax were significantly higher (Mann-Whitney U test) in patients with side-effects. Cmax was [median (interquartile range)] 26.7 (22.7-33.3) mg/l versus 16.2 (13.4-17.0) mg/l (P = 0.001) and Cmin was 12.6 (9.1-13.9) versus 7.5 (4.9-8.6) mg/l (P = 0.002). CONCLUSION Patients with higher ritonavir concentrations are at a higher risk of experiencing neurological or gastrointestinal side-effects. Individualization of the dosage regimen, e.g. a downward titration of the ritonavir dose in patients with side-effects, guided by plasma level monitoring, may result in a substantial increase in the percentage of patients tolerating ritonavir without increasing the risk of treatment failure as a result of suboptimal systemic exposure.

Factors associated with a reduced CD4 lymphocyte count response to HAART despite full viral suppression in the EuroSIDA study

To describe the prevalence and risk factors of poor CD4 count rise despite a good virological response on highly active antiretroviral treatment (HAART).

Gender differences in clinical progression of HIV-1-infected individuals during long-term highly active antiretroviral therapy

Objective: To assess gender differences in the long-term clinical, virological and immunological outcomes during highly active antiretroviral therapy (HAART). Methods: This longitudinal observational multicentre study followed 2460 HIV-infected patients who had begun a protease inhibitor-based regimen for a median period of 43 months. Outcome measures were virological suppression (< 500 copies/ml), confirmed virological rebound after suppression, and death or new AIDS-defining illness (ADI). Results: At baseline, 690 female patients (28.0%) had significantly lower age, higher prevalence of heterosexual contact and lower prevalence of intravenous drug use as risk factors for HIV infection compared with males. Furthermore, females had a lower number of AIDS-defining illnesses, higher CD4 cell counts and lower viral loads. No gender differences were reported in terms of proportion of patients achieving viral suppression or exhibiting rebound after achieving viral suppression. Female patients experienced reduced clinical progression during follow-up compared with males (P = 0.008) by Kaplan–Meier analysis; however this difference was not significant in an adjusted analysis. In a multivariate model, the interaction between gender and risk factor for HIV or viral load showed that female drug users and female patients with a baseline HIV RNA viral load of 104–105 copies/ml had a favourable clinical outcome compared with males (P = 0.035 and P = 0.015, respectively). Conclusion: No differences were found between genders in terms of virological and immunological outcomes during long-term HAART. Nevertheless, a lower risk of clinical progression was reported among female patients with intermediate baseline viral load than in males.

Ritonavir-boosted darunavir combined with raltegravir or tenofovir-emtricitabine in antiretroviral-naive adults infected with HIV-1: 96 week results from the NEAT001/ANRS143 randomised non-inferiority trial

BACKGROUND Standard first-line antiretroviral therapy for HIV-1 infection includes two nucleoside or nucleotide reverse transcriptase inhibitors (NtRTIs), but these drugs have limitations. We assessed the 96 week efficacy and safety of an NtRTI-sparing regimen. METHODS Between August, 2010, and September, 2011, we enrolled treatment-naive adults into this randomised, open-label, non-inferiority trial in treatment-naive adults in 15 European countries. The composite primary outcome was change to randomised treatment before week 32 because of insufficient virological response, no virological response by week 32, HIV-1 RNA concentration 50 copies per mL or higher at any time after week 32; death from any cause; any new or recurrent AIDS event; or any serious non-AIDS event. Patients were randomised in a 1:1 ratio to receive oral treatment with 400 mg raltegravir twice daily plus 800 mg darunavir and 100 mg ritonavir once daily (NtRTI-sparing regimen) or tenofovir-emtricitabine in a 245 mg and 200 mg fixed-dose combination once daily, plus 800 mg darunavir and 100 mg ritonavir once daily (standard regimen). This trial was registered with ClinicalTrials.gov, number NCT01066962. FINDINGS Of 805 patients enrolled, 401 received the NtRTI-sparing regimen and 404 the standard regimen, with median follow-up of 123 weeks (IQR 112-133). Treatment failure was seen in 77 (19%) in the NtRTI-sparing group and 61 (15%) in the standard group. Kaplan-Meier estimated proportions of treatment failure by week 96 were 17·8% and 13·8%, respectively (difference 4·0%, 95% CI -0·8 to 8·8). The frequency of serious or treatment-modifying adverse events were similar (10·2 vs 8·3 per 100 person-years and 3·9 vs 4·2 per 100 person-years, respectively). INTERPRETATION Our NtRTI-sparing regimen was non-inferior to standard treatment and represents a treatment option for patients with CD4 cell counts higher than 200 cells per μL. FUNDING European Union Sixth Framework Programme, Inserm-ANRS, Gilead Sciences, Janssen Pharmaceuticals, Merck Laboratories.