3-Year efficacy and durability of simplification to single tablet regimens: a comparison between co-formulated efavirenz/emtricitabine/tenofovir and rilpivirine/emtricitabine/tenofovir

Observational cohort study of rilpivirine (RPV) utilization in Europe

INTRODUCTION

Data on safety and effectiveness of RPV from the real-world setting as well as comparisons with other NNRTIs such as efavirenz (EFV) remain scarce.

METHODS

Participants of EuroSIDA were included if they had started a RPV- or an EFV-containing regimen over November 2011-December 2017. Statistical testing was conducted using non-parametric Mann-Whitney U test and Chi-square test. A logistic regression model was used to compare participants' characteristics by treatment group. Kaplan-Meier analysis was used to estimate the cumulative risk of virological failure (VF, two consecutive values > 50 copies/mL).

RESULTS

1,355 PLWH who started a RPV-based regimen (11% ART-naïve), as well as 333 initiating an EFV-containing regimen were included. Participants who started RPV differed from those starting EFV for demographics (age, geographical region) and immune-virological profiles (CD4 count, HIV RNA). The cumulative risk of VF for the RPV-based group was 4.5% (95% CI 3.3-5.7%) by 2 years from starting treatment (71 total VF events). Five out of 15 (33%) with resistance data available in the RPV group showed resistance-associated mutations vs. 3/13 (23%) among those in the EFV group. Discontinuations due to intolerance/toxicity were reported for 73 (15%) of RPV- vs. 45 (30%) of EFV-treated participants (p = 0.0001). The main difference was for toxicity of central nervous system (CNS, 3% vs. 22%, p < 0.001).

CONCLUSION

Our estimates of VF > 50 copies/mL and resistance in participants treated with RPV were similar to those reported by other studies. RPV safety profile was favourable with less frequent discontinuation due to toxicity than EFV (especially for CNS).

Long-Term Effectiveness of Rilpivirine-Based Single-Tablet Regimens in a Seven-Year, Two-Center Observational Cohort of People Living with HIV

Data on the long-term durability of rilpivirine (RPV) are still scarce. A two-center retrospective study was performed, including all people living with HIV (PLWH) treated with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC)/RPV or tenofovir alafenamide (TAF)/FTC/RPV in the period January 2013-December 2019. Aims of the study were to assess the rate of discontinuation of the RPV single-tablet regimen (STR) and identify factors associated with the risk of discontinuation according to Cox's regression analysis. A total of 684 PLWH were enrolled. Mean duration of RPV-STR treatment was 192.5 (±99.5) weeks for 123 antiretroviral therapy (ART)-naïve participants (18%) and 173.3 (± 85.6) weeks for 561 ART-experienced study participants (82%). During the study period, the incidence of discontinuation was 7.7 per 100 person-years. The estimated proportions of discontinuation after 48 and 96 weeks were 5.6% and 13.4%, respectively. Causes of discontinuation were loss to follow-up (30%), side effects (15%), ART optimization (14%), virological failure (VF) (12%), death or transfer to another center (9%), low adherence (7%), drug interactions (6%), simplification to dual therapy (3%), and unknown (3%). No differences were observed in cumulative probability of discontinuation between ART-naïve and -experienced PLWH. Heterosexual (hazard ratio [HR] 3.0, 95% confidence interval [CI] 1.4-6.8) and mother-to-child (HR 5.3, 95% CI 1.8-15.3) transmission of HIV infection and history of previous VF (HR 1.7, 95% CI 1.2-2.5) were associated with higher risk of discontinuation. High RPV-STR effectiveness and durability were confirmed in our real-life population of PLWH. Given these data, RPV has the potential to be a drug for life in patients selected according to current guidelines.

Implication of autophagy in the antifibrogenic effect of Rilpivirine: when more is less

As the main extracellular matrix-producing cells, activated hepatic stellate cells (HSC) are fundamental mediators of liver fibrosis (LF), and understanding their activation/inactivation mechanisms is paramount to the search for novel therapeutics. The antiretroviral drug Rilpivirine (RPV) has demonstrated a hepatoprotective effect in several animal models of chronic liver injury that is related to its antifibrogenic and apoptotic action in HSC. In the present study, we evaluated whether autophagy is implicated in the hepatoprotective action of RPV, as autophagy plays an important role in HSC transdifferentiation. We employed two standard mouse models of chronic liver injury - fatty liver disease and carbon tetrachloride (CCl₄)-induced hepatotoxicity -and cultured HSC activated with the profibrotic cytokine TGF-β. RPV enhanced autophagy in the whole liver of both mouse models and in activated HSC, evident in the protein expression of autophagy markers, increased autophagosome content and lysosomal mass. Moreover, increased autophagic flux was observed in RPV-exposed HSC as revealed by tandem fluorescence-tagged LC3 and p62 and analysis of LC3-II accumulation in cells exposed to the lysosomal inhibitor chloroquine. Importantly, autophagy was involved in the cytotoxic effect of RPV on HSC, though in a differential manner. Pharmacological inhibition of autophagy by 3-methyladenine (3-MA) did not affect the diminishing effect of RPV on viability, while treatment with wortmannin or depletion of specific autophagy proteins (ATG5, Beclin-1 and SQSTM1/p62) rescued the detrimental effect of high concentrations of RPV on the viability of activated HSC. Finally, we also provide evidence that RPV compromises the viability of TGF-β-induced HSC independently of its antifibrogenic effect, observed as reduced collagen 1A1 synthesis, and that this effect does not include RPV´s modulation of autophagy. In summary, as a contributor to the mechanisms involved in the hepatoprotective action of RPV, autophagy may be a good candidate to explore when developing novel therapeutics for LF.

Comparison of the efficacy, safety and durability of a switch to co-formulated RPV/TDF-TAF/FTC or DTG/ABC/3TC in virologically-suppressed HIV-1-infected patients in a single Italian centre: a cohort data analysis

This study evaluated the efficacy, safety and durability of a switch to co-formulated RPV/TDF-TAF/FTC (RPV-STR) or DTG/ABC/3TC (DTG-STR) in virologically-suppressed HIV-positive patients in a single Italian centre. All HIV-infected ART-experienced patients switching to RPV-STR or DTG-STR with HIV-RNA <50 copies/mL were included. Outcomes were incidence rate and rate ratios for discontinuation due to all causes (DAC), to adverse events (DAE) and to virological failure (VF) after 4 years of follow-up. We included 402 patients (244 on RPV-STR, 158 on DTG-STR). At Year 4 of follow-up, 124 patients (30.8%) discontinued for any cause (71 on RPV-STR, 53 on DTG-STR). Fifteen patients experienced VF [13 (5.3%) on RPV-STR and 2 (1.3%) on DTG-STR; log-rank, P = 0.4413]. Overall, 46 patients (11.4%) had AEs (23 on RPV-STR, 23 on DTG-STR). Nausea/diarrhoea was more frequent with DTG-STR (4.4% vs. 0%) and neurological toxicity with RPV-STR (4.5% vs. 2.5%). The rate of DAC within the first 3 months was significantly higher with DTG-STR (aRR = 5.88, 95% CI 3.20-10.81; P < 0.001); similarly, the discontinuation rate due to AEs was significantly higher with DTG-STR compared with RPV-STR (aRR = 12.89, 95% CI 5.48-30.32; P < 0.001). No difference in VF was observed between the two groups (RR = 0.47, 95% CI 0.10-2.14; P = 0.335). Patients with undetectable viral load who switched to DTG-STR or RPV-STR maintained virological suppression with a low risk of VF. A higher discontinuation rate was observed with DTG-STR compared with RPV-STR, particularly within 3 months from switch.

Usefulness of therapeutic drug monitoring of rilpivirine and its relationship with virologic response and resistance in a cohort of naive and pretreated HIV-infected patients

AIMS

The purpose of this study was to assess the antiviral activity of the rilpivirine/emtricitabine/tenofovir disoproxil fumarate combination and to describe the pharmacokinetics of rilpivirine and its association with resistance in clinical routine.

METHODS

A retrospective multicentre cohort study was performed in both naive and pretreated HIV patients receiving the once-daily rilpivirine/emtricitabine/tenofovir disoproxil fumarate regimen. Immuno-virologic and resistance data, and rilpivirine plasma trough concentrations were collected over the follow-up. Statistical analyses were performed to evaluate the relationship between rilpivirine pharmacokinetics and virological response. Receiver operating characteristic (ROC) curve analysis was performed to determine the best target rilpivirine trough concentration.

RESULTS

Overall, 379 patients were included. After a median follow-up of 28 months, 26% of patients discontinued mainly due to toxicity and the virological success rate was 65.7%. Virological failure occurred in 5% of patients. A significant proportion of patients with HIV-RNA > 40 copies/mL displayed rilpivirine plasma trough concentrations below the currently used 50 ng/mL efficacy threshold at both M6 (28%) and M12 (31%), in agreement with a significant lower median rilpivirine plasma trough concentration compared with patients virologically suppressed. Half of the patients with virologic failure who acquired rilpivirine resistance mutations had at least one suboptimal rilpivirine trough concentration. The optimal target for rilpivirine trough concentration was 70 ng/mL (sensitivity 75.4%; specificity 61.5%).

CONCLUSIONS

This study shows the impact of rilpivirine plasma trough concentration on both virological response and the emergence of rilpivirine mutations. Moreover, our results suggest that a higher target of rilpivirine trough concentration could be proposed in clinical practice.

Rilpivirine attenuates liver fibrosis through selective STAT1-mediated apoptosis in hepatic stellate cells

OBJECTIVE

Liver fibrosis constitutes a major health problem worldwide due to its rapidly increasing prevalence and the lack of specific and effective treatments. Growing evidence suggests that signalling through cytokine-activated Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathways regulates liver fibrosis and regeneration. Rilpivirine (RPV) is a widely used anti-HIV drug not reported to produce hepatotoxicity. We aimed to describe the potential hepatoprotective effects of RPV in different models of chronic liver injury, focusing on JAK-STAT signalling regulation.

DESIGN

The effects of RPV on hepatic steatosis, inflammation and fibrogenesis were studied in a nutritional mouse model of non-alcoholic fatty liver disease, carbon tetrachloride-induced fibrosis and bile duct ligation-induced fibrosis. Primary human hepatic stellate cells (hHSC) and human cell lines LX-2 and Hep3B were used to investigate the underlying molecular mechanisms.

RESULTS

RPV exerted a clear anti-inflammatory and antifibrotic effect in all the in vivo models of liver injury employed, and enhanced STAT3-dependent proliferation in hepatocytes and apoptosis in HSC through selective STAT1 activation. These results were reproduced in vitro; RPV undermined STAT3 activation and triggered STAT1-mediated pathways and apoptosis in HSC. Interestingly, this selective pro-apoptotic effect completely disappeared when STAT1 was silenced. Conditioned medium experiments showed that HSC apoptosis activated STAT3 in hepatocytes in an interleukin-6-dependent mechanism.

CONCLUSION

RPV ameliorates liver fibrosis through selective STAT1-dependent induction of apoptosis in HSC, which exert paracrinal effects in hepatocytes, thus promoting liver regeneration. RPV's actions may represent an effective strategy to treat chronic liver diseases of different aetiologies and help identify novel therapeutic targets.

HIV-1 genotypic drug resistance in patients with virological failure to single-tablet antiretroviral regimens in southern Taiwan

Purpose

Sparse data are available on the prevalence of resistance among HIV-1-infected patients with virological failure to a single-tablet regimen (STR). This study aimed to evaluate the prevalence of HIV genotypic drug resistance in HIV-1-infected patients with virological failure to STRs in southern Taiwan.

Patients and methods

This retrospective study investigated drug resistance in patients with virological failure to STR from January 2016 to September 2017. Antiretroviral resistance mutations were defined using the 2017 International AIDS Society-USA HIV drug resistance algorithm, and drug resistance was compared using the HIVdb program of the Stanford University HIV Drug Resistance Database. Variables between resistance and non-resistance groups were compared.

Results

Thirty-nine HIV-1-infected patients with treatment failure were tested for resistance, of whom 89% were infected by men who have sex with men. Subtype B HIV-1 strains were found in 90% of the patients. Eight patients were treatment naïve and initiated STRs, while 31 patients experienced treatment failure after switching to STRs. Eighty-seven percent of the patients harbored any of four classes of resistance (nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors (PIs), and integrase strand transfer inhibitors). The prevalence rates of nucleoside reverse transcriptase inhibitor, non-nucleoside reverse transcriptase inhibitor, PI, and integrase strand transfer inhibitor resistance were 72%, 82%, 10%, and 3%, respectively. Patients with PI resistance were more likely to respond to treatment with a non-tenofovir disoproxil fumarate/emtricitabine/efavirenz-based STR (.=0.004) and a longer duration of antiretroviral therapy (101 months [72.0-123.3] vs 11 months [7-44], P=0.007). There were no associations between different STRs and transmission risk factors, HIV subtype, duration of antiretroviral therapy, and resistance to tenofovir disoproxil fumarate.

Conclusion

A high rate of antiretroviral drug resistance was found in the patients who failed STR treatment. The presence of PI resistance in these patients represented an inappropriate switch from a multiple tablet regimen to an STR. These findings should remind clinicians that detailed drug resistance history and close monitoring are mandatory after switching to an STR.

Improvement of lipid profile after switching from efavirenz or ritonavir-boosted protease inhibitors to rilpivirine or once-daily integrase inhibitors: results from a large observational cohort study (SCOLTA)

Background

Dyslipidemia represents a significant non-infectious comorbidity among people living with HIV. The aim of this study is to evaluate the impact on lipid profile of switches from an efavirenz (EFV) or protease inhibitor/ritonavir (PI/r)-based regimen to a rilpivirine (RPV) or a once-daily integrase inhibitor-based regimen.

Methods

We analyzed data from SCOLTA prospective database. All patients with HIV-RNA < 50 copies/ml in therapy with two NRTI + EFV or PI/r were included if they switched from EFV to dolutegravir (group EFV-DTG), elvitegravir (EFV-EVG), or RPV (EFV-RPV) and from PI/r to DTG (PI/r-DTG), PI/r to EVG (PI/r-EVG), or PI/r to RPV (PI/r-RPV). Total cholesterol (TC), TC/HDL ratio, LDL-cholesterol (LDL) and triglycerides (TG) were compared at baseline, six months and one year. Comparisons among groups were performed by a general linear model.

Results

Four hundred and ninety patients were enrolled, 24.9% female, mean age 47.3 years (±10.1). According to ART switch, 11.4% were classified in group EFV-DTG, 3.9% in EFV-EVG, 23.9% in EFV-RPV, 17.6% in PI/r-DTG, 17.8% in PI/r-EVG, and 25.5% in PI/r-RPV. After adjusted analysis, TC significantly decreased in all groups but EFV-EVG, TC/HDL in all but EFV-DTG and EFV-EVG, while the reduction of TG was significant only in switches to RPV (EFV-RPV and PI/r-RPV). The one year decrease of TC, TC/HDL, LDL and TG was higher in patients with higher baseline levels of the same variable (p < .0001 for all).

Conclusions

In SCOLTA, all switches from PI/r regimens gave advantages on lipid profile, while stopping EFV had consistently favorable lipid effects only if replaced by RPV.