Immunovirological Efficacy of Once-Daily Maraviroc Plus Ritonavir-Boosted Atazanavir After 48 Weeks in Naive HIV-Infected Patients

Risk of failure in dual therapy versus triple therapy in naïve HIV patients: a systematic review and meta-analysis

OBJECTIVES

Several attempts have been made to test different drug-sparing strategies to reduce the drug-burden and drug-related toxicities. The objective of this meta-analysis was to evaluate the relative risk (RR) of failure of dual therapies compared to triple therapies in HIV-naïve patients.

METHODS

We searched MEDLINE, Google Scholar and the Cochrane Library. The following criteria were used: present data from original articles comparing the two treatment regimens; published from January 2007 up to January, 2020. No language or study design restriction was applied. Subjects were HIV-positive naïve patients treated with dual or triple antiretroviral therapy (ART). A systematic review and meta-analysis was performed. Treatment failure (TF) was the primary outcome evaluated; heterogeneity was assessed using the Q statistic and I².

RESULTS

Fourteen studies were included, allowing a meta-analysis on 5205 patients. The meta-analysis performed on studies that presented data at 48 weeks showed that the RR of TF (RR > 1 favouring triple therapy) in 10 studies was 1.20 (95% confidence interval (CI): 0.91-1.59, I²: 49.2%); the RR of virological failure (VF) in eight studies was 1.54 (95% CI: 0.84-2.86, I²: 54%); the RR of adverse drug reaction leading to discontinuation of the regimen at 48 weeks in eight studies was 0.76 (95% CI: 0.43-1.33, I²: 17.7%). In patients with less than 200 CD4+, the RR of TF in two studies without maraviroc was 2.09 (95% CI: 1.05-4.17, I²: 0.0%). Regarding the studies at 96 weeks there was no difference except in rate of development of resistance, RR 1.94 (95% CI: 1.06-3.53, I²: 6.2%).

CONCLUSION

Dual therapies are as effective as those with three drugs, showing no difference according to the different dual therapies, except in patients with less than 200 CD4; however, they are associated with a higher selection of resistance-associated mutations at 96 weeks of therapy.

New Strategies of ARV: the Road to Simplification

PURPOSE OF REVIEW

Simplification of antiretroviral therapy is a strategy aiming to reduce pill burden, drug interactions, and toxicity. This review focuses on the most recent and important studies evaluating a reduction on the number of drugs for HIV treatment, both in naive and virologically suppressed patients.

RECENT FINDINGS

Interesting studies have been performed in the past years testing dual therapy and monotherapy, with variable rates of virological control. Novel therapeutics like immunotherapy or long-acting antiretrovirals can also be considered for simplification. Reducing the number of drugs for HIV treatment can be an option for selected patients. Current available evidence favors dual therapy over monotherapy. Future research should seek to identify the best candidates for simplification.

Two-drug regimens for treatment of naïve HIV-1 infection and as maintenance therapy

As people live longer with HIV infection, there has been a resurgence of interest in challenging the use of three-drug therapy, including two nucleoside reverse transcriptase inhibitors plus a third drug, as initial treatment of HIV infection or for maintenance therapy in virologically suppressed individuals. Although initial studies showed poor efficacy and/or substantial toxicity, more recent regimens have held greater promise. The SWORD-1 and -2 studies were pivotal trials of dolutegravir plus rilpivirine as maintenance therapy in virologically suppressed patients with no history of drug resistance, leading to the US Food and Drug Administration’s approval of the regimen as a small, single tablet. More recently, the GEMINI-1 and -2 studies demonstrated that dolutegravir plus lamivudine is as safe and effective as the same regimen when combined with tenofovir disoproxil fumarate in treatment-naïve individuals. Together, these and other studies of novel two-drug regimens offer the potential for improved tolerability and simplicity, as well as a reduction in cost. We will review historical and recent trials of two-drug therapy for the treatment of HIV-1 infection.

Improved CD4 T cell profile in HIV-infected subjects on maraviroc-containing therapy is associated with better responsiveness to HBV vaccination

Background

Maraviroc-containing combined antiretroviral therapy (MVC-cART) improved the response to the hepatitis B virus (HBV) vaccine in HIV-infected subjects younger than 50 years old. We aimed here to explore the effect of this antiretroviral therapy on different immunological parameters that could account for this effect.

Methods

We analysed baseline samples of vaccinated subjects under 50 years old (n = 41). We characterized the maturational subsets and the expression of activation, senescence and prone-to-apoptosis markers on CD4 T-cells; we also quantified T-regulatory cells (Treg) and dendritic cell (DC) subsets. We used binary logistic regression to evaluate the immunological impact of MVC-cART, correlation with MVC exposure and linear regression for association with the magnitude of the HBV vaccine response.

Results

HIV-infected subjects on MVC-cART prior to vaccination showed increased recent thymic emigrants levels and reduced myeloid-DC levels. A longer exposure to MVC-cART was associated with lower frequencies of Tregs and activated and proliferating CD4 T-cells. Furthermore, the frequencies of activated and proliferating CD4 T-cells were inversely associated with the magnitude of the HBV vaccine response.

Conclusion

The beneficial effect of MVC-cART in the HBV vaccine response in subjects below 50 years old could be partially mediated by its reducing effect on the frequencies of activated and proliferating CD4 T-cells prior to vaccination.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1617-1) contains supplementary material, which is available to authorized users.

Increased CD127+ and decreased CD57+ T cell expression levels in HIV-infected patients on NRTI-sparing regimens

BACKGROUND

NRTIs-sparing regimens exert favourable profiles on T-cell homeostasis associated parameters. Our aim was to analyze the effect of NRTIs sparing regimen (NRTI-sparing-cART) vs NRTIs-containing regimen (NRTI-cART), on T-cell homeostasis associated parameters in naive HIV-infected patients.

METHODS

Biomarkers of cell survival (CD127) and replicative senescence (CD57), were measured by multiparametric flow cytometry for T-cell phenotyping on peripheral blood mononuclear cells (PBMCs) samples just before (baseline) and after 48 weeks of undetectable viral load in patients on NRTI-sparing-cART (N = 13) and NRTI-cART (N = 14). After 48 weeks a subgroup of patients (n = 5) on NRTI-cART switched to NRTI-sparing-cART for another additional 48 weeks. In vitro assays were performed on PBMCs from HIV-uninfected healthy donors exposed or not to HIV. To analyze the independent factors associated with type of cART bivariate and stepwise multivariate analysis were performed after adjusting for basal CD4+, CD8+ and nadir CD4+ T-cell counts.

RESULTS

After 48 weeks of a NRTI-sparing-cART vs NRTI-cART patients have higher effector memory (EM) CD4+ CD127+ T-cell levels, lower EM CD4+ CD57+ T-cell levels, higher CD8+ CD127+ T-cell levels, lower CD8+ CD57+ T-cell levels and higher memory CD8+ T-cell levels. This effect was confirmed in the subgroup of patients who switched to NRTI-sparing-cART. In vitro assays confirmed that the deleterious effect of a NRTIs-containing regimen was due to NRTIs.

CONCLUSIONS

The implementation of NRTI-sparing regimens, with a favourable profile in CD127 and CD57 T-cell expression, could benefit cART-patients. These results could have potential implications in a decrease in the number of Non-AIDS events.

Dual antiretroviral therapy for HIV infection

INTRODUCTION

For two decades, triple combinations of antiretrovirals have been the standard treatment for HIV infection. The challenges of such lifelong therapy include long-term side effects, high costs and reduced drug adherence. The recent advent of more potent and safer antiretrovirals has renewed the interest for simpler HIV regimens. Areas covered: We discuss the pros and cons of dual antiretroviral therapies in both drug-naïve and in treatment-experienced patients with viral suppression (switch strategy). Expert opinion: Some dual antiretroviral regimens are safe and efficacious, particularly as maintenance therapy. At this time, combinations of dolutegravir plus rilpivirine represent the best dual regimen. Longer follow-up and larger study populations are needed before supporting dolutegravir plus lamivudine. In contrast, dual therapy based on maraviroc is less effective. Although dual regimens with boosted protease inhibitors plus either lamivudine or raltegravir may be effective, they are penalized by metabolic side effects and risk for drug interactions. The newest dual regimens could save money, reduce toxicity and spare drug options for the future. For the first time in HIV therapeutics, less can be more. Dual therapy switching has set up a new paradigm in HIV treatment that uses induction-maintenance.