Yvon van Delft

The MONET trial: darunavir/ritonavir with or without nucleoside analogues, for patients with HIV RNA below 50 copies/ml.

Background: In virologically suppressed patients, darunavir-ritonavir (DRV/r) monotherapy could maintain virological suppression similarly to DRV/r and two nucleosides. Methods: Two hundred and fifty-six patients with HIV RNA less than 50 copies/ml for over 24 weeks on current antiretrovirals [non-nucleoside reverse transcriptase inhibitor (NNRTI)-based (43%), or protease inhibitor-based (57%)], switched to DRV/r 800/100 mg once daily, either as monotherapy (n = 127) or with two nucleoside reverse transcriptase inhibitors (NRTIs) (n = 129). Treatment failure was defined as two consecutive HIV RNA levels above 50 copies/ml (TLOVR) by week 48, or switches off study treatment. The trial had 80% power to show noninferiority for the monotherapy arm (delta = −12%). Results: Patients were 81% male and 91% Caucasian, with mean age 44 years, and CD4 cell count of 574 cells/μl. In the primary efficacy analysis, HIV RNA less than 50 copies/ml by week 48 (per protocol) was 86.2 versus 87.8% in the monotherapy and triple therapy arms; by intent-to-treat switch equals failure, efficacy was 84.3 versus 85.3%; by a switch-included analysis, efficacy was 93.5 versus 95.1%: all three comparisons showed noninferior efficacy for DRV/r monotherapy. CD4 cell counts remained stable during the trial in both arms. One patient per arm showed at least one protease inhibitor mutation, and one patient in the triple therapy arm showed an NRTI mutation. Nine patients per arm discontinued randomized treatment for either adverse events or other reasons. No new or unexpected safety signals were detected. Conclusions: In this study for patients with HIV RNA less than 50 copies/ml on other antiretrovirals at baseline, switching to DRV/r monotherapy showed noninferior efficacy versus triple antiretroviral therapy.

The PROTEA trial: darunavir/ritonavir with or without nucleoside analogues, for patients with HIV-1 RNA below 50 copies/mL

In previous studies, protease inhibitor (PI) monotherapy has shown trends for higher low‐level elevations in HIV‐1 RNA compared to triple therapy, but no increase in the risk of drug resistance.

A comparison of neuropsychiatric adverse events during 12 weeks of treatment with etravirine and efavirenz in a treatment-naive, HIV-1-infected population

Background:Although efavirenz is a universally recommended treatment for naive HIV-infected individuals, neuropsychiatric adverse events are common. Methods:The Study of Efavirenz NeuropSychiatric Events versus Etravirine (SENSE) trial is a double-blind, placebo-controlled study in which 157 treatment-naive individuals with HIV-RNA higher than 5000 copies/ml were randomized to etravirine 400 mg once daily (n = 79) or to efavirenz 600 mg once daily (n = 78), with two investigator-selected nucleoside reverse transcriptase inhibitors (NRTIs). The primary end point was the percentage of patients with grade 1–4 drug-related treatment-emergent neuropsychiatric adverse events up to week 12. Results:The study population were 81% men and 85% whites, with a median age of 36 years, baseline CD4 cell counts of 302 cells/μl and HIV-RNA of 4.8 log10 copies/ml. In the intent-to-treat analysis, 13 of 79 individuals (16.5%) in the etravirine arm and 36 of 78 individuals (46.2%) in the efavirenz arm showed at least one grade 1–4 drug-related treatment-emergent neuropsychiatric adverse event (P < 0.001). The number with at least one grade 2–4 drug-related treatment-emergent neuropsychiatric adverse event was four of 79 individuals (5.1%) in the etravirine arm and 13 of 78 individuals (16.7%) in the efavirenz arm (P = 0.019). The change in HIV-RNA to week 12 was −2.9 log10 in both treatment arms. The median rise in CD4 cell counts was 146 cells/μl in the etravirine arm and 121 cells/μl in the efavirenz arm. Conclusions:After 12 weeks, first-line treatment with etravirine 400 mg once daily with two NRTIs was associated with significantly fewer neuropsychiatric adverse events when compared with efavirenz with two NRTIs. The virological and immunological efficacy profile was similar between the two arms.

Dynamics of Cellular HIV-1 DNA Levels Over 144 Weeks of Darunavir/Ritonavir Monotherapy Versus Triple Therapy in the MONET Trial

Abstract Background: In patients receiving combination antiretroviral therapy (ART), switching to monotherapy with ritonavir-boosted darunavir (DRV/r) can maintain plasma HIV-1 RNA suppression with no treatment-emergent drug resistance; effects on cellular HIV-1 DNA burden are less well characterized. Methods: In MONET, patients on stable combination ART for at least 6 months with plasma HIV-1 RNA <50 copies/mL and no history of virologic failure switched to DRV/r 800/100 mg once daily, either alone (n = 127) or with 2 nucleos(t)ide reverse transcriptase inhibitors (NRTIs) (n = 129). In a representative subset of 146 patients, total HIV-1 DNA load in peripheral blood mononuclear cells (PBMC) was tested retrospectively at baseline, week 48, week 96, and week 144. Results: Mean HIV-1 DNA levels at baseline vs week 144 were 2.50 vs 2.49 log10 copies/106 PBMC in the monotherapy arm and 2.59 vs 2.61 log10 copies/106 PBMC in the triple therapy arm, with mean (median) changes of -0.05 (-0.03) and +0.03 (+0.01) log10 copies/106 PBMC in the 2 arms, respectively. Overall baseline HIV-1 DNA levels were higher in patients with nadir CD4 counts <200 cell/µL (P<.05) and in patients who over 144 weeks experienced at least 1 HIV-1 RNA measurement >50 copies/mL (P < .05). Conclusions: In this substudy of the MONET trial, HIV-1 DNA levels remained stable during 144 weeks of either DRV/r monotherapy or triple therapy with DRV/r + 2 NRTIs. In both treatment arms, baseline HIV-1 DNA levels were predicted by the nadir CD4 cell count and predictive of plasma HIV-1 RNA detection during follow-up.

Pharmacokinetic interaction between etravirine or rilpivirine and telaprevir in healthy volunteers: A randomized, two‐way crossover trial

Coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) may require treatment with an HIV non‐nucleoside reverse transcriptase inhibitor (NNRTI), for example, rilpivirine or etravirine, and an HCV direct‐acting antiviral drug such as telaprevir. In a two‐panel, two‐way, crossover study, healthy volunteers were randomized to receive etravirine 200 mg twice daily ± telaprevir 750 mg every 8 hours or rilpivirine 25 mg once daily ± telaprevir 750 mg every 8 hours. Pharmacokinetic assessments were conducted for each drug at steady‐state when given alone and when coadministered; statistical analyses were least‐square means with 90% confidence intervals. Telaprevir minimum plasma concentration (Cmin), maximum plasma concentration (Cmax), and area under the concentration–time curve (AUC) decreased 25%, 10%, and 16%, respectively, when coadministered with etravirine and 11%, 3%, and 5%, respectively, when coadministered with rilpivirine. Telaprevir did not affect etravirine pharmacokinetics, but increased rilpivirine Cmin, Cmax, and AUC by 93%, 49%, and 78%, respectively. Both combinations were generally well tolerated. The small decrease in telaprevir exposure when coadministered with etravirine is unlikely to be clinically relevant. The interaction between telaprevir and rilpivirine is not likely to be clinically relevant under most circumstances. No dose adjustments are deemed necessary when they are coadministered.

Sensitive testing of plasma HIV-1 RNA and Sanger sequencing of cellular HIV-1 DNA for the detection of drug resistance prior to starting first-line antiretroviral therapy with etravirine or efavirenz

OBJECTIVES This study investigated strategies that may increase the yield of drug resistance testing prior to starting antiretroviral therapy (ART), and whether transmitted and polymorphic resistance-associated mutations (RAMs) correlated with virological outcomes. METHODS We carried out retrospective testing of baseline samples from patients entering the SENSE trial of first-line ART in Europe, Russia and Israel. Prior to randomization to etravirine or efavirenz plus two nucleos(t)ide reverse transcriptase inhibitors (NRTIs), plasma samples underwent routine Sanger sequencing of HIV-1 RT and protease ((plasma)SS) in order to exclude patients with transmitted RAMs. Retrospectively, Sanger sequencing was repeated with HIV-1 DNA from baseline peripheral blood mononuclear cells (PBMCSS); baseline plasma samples were retested by allele-specific PCR targeting seven RT RAMs (AS-PCR) and ultra-deep RT sequencing (UDS). RESULTS By (plasma)SS, 16/193 (8.3%) patients showed ≥ 1 transmitted RAM affecting the NRTIs (10/193, 5.2%), non-nucleoside reverse transcriptase inhibitors (4/193, 2.1%) or protease inhibitors (2/193, 1.0%). No additional RAMs were detected by AS-PCR (n = 152) and UDS (n = 24); PBMCSS (n =  91) yielded two additional samples with one RAM each. Over 48 weeks, 4/79 (5.1%) patients on etravirine and 7/78 (9.0%) on efavirenz experienced virological failure; none had baseline RAMs. Conversely, 11/79 (13.9%) patients randomized to etravirine had one polymorphic RAM from the etravirine score in baseline plasma (V90I, V106I or E138A), without any impact on virological outcomes. CONCLUSIONS The detection of resistance increased marginally with PBMC testing but did not increase with sensitive plasma testing. A careful consideration is required of the cost-effectiveness of different strategies for baseline HIV drug resistance testing.

Analysis of drug resistance during HIV RNA viraemia in the MONET trial of darunavir/ritonavir monotherapy.

BACKGROUND When patients have HIV RNA suppressed to <50 copies/ml on current treatment, switching to darunavir (DRV)/ritonavir (DRV/r) monotherapy could prevent the development of resistance to other drug classes. METHODS In the MONET trial, 256 patients with HIV RNA<50 copies/ml on current highly active antiretroviral therapy (57% with protease inhibitors [PIs] and 43% with non-nucleoside reverse transcriptase inhibitors) and no history of virological failure were randomized to DRV/r 800/100 mg once daily, either as monotherapy (monotherapy arm) or with two nucleoside reverse transcriptase inhibitors (NRTIs; triple therapy arm). All samples with HIV RNA ≥ 50 copies/ml were genotyped, and a virtual phenotype was calculated (VircoType HIV-1 assays; Virco BVBA, Mechelen, Belgium). RESULTS A total of 63 patients had ≥ 1 HIV RNA result ≥ 50 copies/ml, of whom 38 were successfully genotyped. Most HIV RNA increases were transient and in the range of 50-200 copies/ml. Overall, 36 of the 38 (95%) successfully genotyped patients showed no International AIDS Society-USA major PI mutations, DRV mutations or NRTI mutations. Two patients showed some evidence of PI resistance during transient HIV RNA elevations: one patient in the monotherapy arm had a single DRV mutation (L33F) when HIV RNA was 63 copies/ml (the virus was phenotypically sensitive to DRV [fold change 0.8]) and one PI pretreated patient taking tenofovir disoproxil fumarate/emtricitabine/DRV/r had re-emergence of pre-existing NRTI (M184V) and PI (V82I and L90M) mutations after a short treatment interruption (this virus remained phenotypically sensitive to DRV/r). Both patients showed sustained HIV RNA suppression to week 48 remaining with the same treatment. CONCLUSIONS Emergence of drug resistance after changing a suppressive triple antiretroviral therapy to DRV/r with or without nucleoside analogues is uncommon.

No difference in the rate of change in telomere length or telomerase activity in HIV-infected patients after three years of darunavir/ritonavir with and without nucleoside analogues in the MONET trial.

Objective To determine whether nucleos(t)ide reverse transcriptase inhibitors (NRTI) contribute to an accelerated loss in telomere length (TL) in HIV-infected patients on antiretroviral therapy (ART). Design Substudy of randomised controlled trial. Methods Patients with HIV RNA <50 copies/mL on combination ART (n = 256) were randomised to darunavir/ritonavir (DRV/r) 800/100 mg once daily, either as monotherapy (n = 127) or with 2 NRTIs (n = 129) for up to 144 weeks. TL and telomerase activity was quantified on stored peripheral blood mononuclear cells (PBMC; n = 124) using quantitative real time PCR. Results Patients in the sub-study had a mean age of 44 years and had received NRTI for a mean of 6.4 years (range 1–20 years). As expected, older patients have significantly shorter TL (p = 0.006), while women had significantly longer TL (p = 0.026). There was no significant association between TL and either the duration of prior NRTI treatment (p = 0.894) or the use of a PI versus NNRTI (p = 0.107). There was no significant difference between patients who continued or ceased NRTI in the mean change/year of TL or telomerase (p = 0.580 and 0.280 respectively). Conclusion Continuation versus cessation of NRTI treatment was not associated with an accelerated loss in TL or telomerase activity.

Pharmacokinetics and Pharmacodynamics of Etravirine 400 mg Once Daily in Treatment-Naïve Patients

Abstract Background: Etravirine is currently approved for HIV treatment–experienced patients at a dose of 200 mg twice daily. The long terminal elimination half-life of etravirine should support once-daily dosing.Methods: In the double-blind 48-week SENSE trial, 157 antiretroviral treatment–naïve patients were randomly assigned to receive etravirine 400 mg once daily (n = 79) or efavirenz 600 mg once daily (n = 78), plus 2 nucleoside reverse transcriptase inhibitors (NRTIs). Sparse sampling for etravirine plasma concentrations was conducted during the 48-week trial. Area under the curve over the dosing interval (AUC24) and trough concentration (C0) were estimated using a population pharmacokinetic model and compared with previous results using the 200-mg twice-daily dosage. The relationship between etravirine AUC24 and C0 with efficacy and safety was also assessed.Results: By week 48, the percentage of patients in the etravirine arm with HIV RNA <50 copies/ mL was 75.9% in the intent-to-treat switch equals failure analysis and 92.3% in the on-treatment analysis; no patient developed genotypic or phenotypic resistance to NRTIs or non-nucleoside reverse transcriptase inhibitors (NNRTIs) after virologic failure. Seventy-one subjects had evaluable etravirine pharmacokinetics. The median (interquartile range) of etravirine AUC24 and C0 were 12,447 (8,261–15,652) ng•h/mL and 330 (188–472) ng/mL, respectively. There was no correlation between etravirine exposure and virologic response or adverse events.Conclusions: In the SENSE trial, etravirine 400 mg once daily achieved similar exposures to historical reference data on etravirine when dosed at 200 mg twice daily. There was no apparent relationship between the pharmacokinetics of etravirine and virologic response or adverse events.

Etravirine as a Switching Option for Patients with HIV RNA Suppression: A Review of Recent Trials.

Unlike other nonnucleoside reverse transcriptase inhibitors, etravirine is only approved for use in treatment-experienced patients. In the DUET 1 and 2 trials, 1203 highly treatment-experienced patients were randomized to etravirine or placebo, in combination with darunavir/ritonavir and optimized background treatment. In these trials, etravirine showed significantly higher rates of HIV RNA suppression when compared with placebo (61% versus 40% at Week 48). There was no significant rise of lipids or neuropsychiatric adverse events, but there was an increase in the risk of rash with etravirine treatment. In the SENSE trial, which evaluated etravirine and efavirenz in 157 treatment-naïve patients in combination with 2 nucleoside analogues, there was a lower risk of lipid elevations and neuropsychiatric adverse events with etravirine when compared to efavirenz. Etravirine has been evaluated in three randomized switching studies. In the SSAT029 switch trial, 38 patients who had neuropsychiatric adverse events possibly related to efavirenz showed an improvement in these after switching to etravirine. The Swiss Switch-EE recruited 58 individuals without neuropsychiatric adverse events who were receiving efavirenz, and no benefit was shown when switching to etravirine. In the Spanish ETRA-SWITCH trial (n = 46), there were improvements in lipids when individuals switched from a protease inhibitor to etravirine. These switching trials were conducted in patients with full HIV RNA suppression: <50 copies/mL and with no history of virological failure or resistance to therapy. The results from these three randomized switching studies suggest a possible new role for etravirine, in combination with two nucleoside analogues, as a switching option for those with HIV RNA suppression but who are reporting adverse events possibly related to antiretroviral therapy. However a large well-powered trial would need to be conducted to strengthen the evidence from the pilot studies conducted so far.