Switch to fixed-dose doravirine (100 mg) with islatravir (0·75 mg) once daily in virologically suppressed adults with HIV-1 on bictegravir, emtricitabine, and tenofovir alafenamide: 48-week results of a phase 3, randomised, controlled, double-blind, non-inferiority trial.

BACKGROUND: Doravirine and islatravir is an investigational, once-daily regimen with high antiviral potency, favourable safety and tolerability, and a low propensity for resistance. We investigated a switch from bictegravir, emtricitabine, and tenofovir alafenamide to doravirine (100 mg) and islatravir (0·75 mg) in virologically suppressed adults with HIV-1. METHODS: We conducted a phase 3, multicentre, randomised, active-controlled, double-blind, double-dummy, non-inferiority trial at 89 research, community, and hospital-based clinics in 11 countries. Adults aged 18 years or older with fewer than 50 HIV-1 RNA copies per mL for at least 3 months on bictegravir (50 mg), emtricitabine (200 mg), and tenofovir alafenamide (25 mg) and no history of previous virological failure on any past or current regimen were randomly assigned (1:1) by a computer-generated randomisation allocation schedule, with block randomisation based on a block size of four, to switch to doravirine (100 mg) and islatravir (0·75 mg) or continue bictegravir, emtricitabine, and tenofovir alafenamide orally once daily, with matching placebos taken by all participants. Participants, investigators, study staff, and sponsor personnel involved in study drug administration or clinical evaluation of participants were masked to treatment assignment until week 48. Participants were instructed at each visit to take one tablet from each of the two bottles received, one of study drug and one of placebo, once daily, and participants were assessed at baseline and weeks 4, 12, 24, 36, and 48. The primary endpoint was the proportion of participants with greater than or equal to 50 HIV-1 RNA copies per mL at week 48 in the full analysis set (ie, all participants who received at least one dose of study drug; US Food and Drug Administration snapshot; prespecified non-inferiority margin 4%). The study is ongoing, with all remaining participants in post-treatment follow-up, and is registered with ClinicalTrials.gov, NCT04223791. FINDINGS: We screened 726 individuals for eligibility between Feb 18 and Sept 3, 2020, of whom 643 (88·6%) participants were randomly assigned to a treatment group (183 [28·5%] women and 460 [71·5%] men). 322 participants were switched to doravirine (100 mg) and islatravir (0·75 mg) and 321 continued bictegravir, emtricitabine, and tenofovir alafenamide (two participants [one with a protocol deviation and one who withdrew] assigned to bictegravir, emtricitabine, and tenofovir alafenamide did not receive treatment). The last follow-up visit for the week 48 analysis occurred on Aug 26, 2021. At week 48, two (0·6%) of 322 participants in the doravirine and islatravir group compared with one (0·3%) of 319 participants in the bictegravir, emtricitabine, and tenofovir alafenamide group had greater than or equal to 50 HIV-1 RNA copies per mL (difference 0·3%, 95% CI -1·2 to 2·0). The per-protocol analysis showed consistent results. 25 (7·8%) participants in the doravirine and islatravir group had headache compared with 23 [7·2%] participants in the bictegravir, emtricitabine, and tenofovir alafenamide group; 101 (31·4%) compared with 98 (30·7%) had infections; and eight (2·5%) participants in each group discontinued therapy due to adverse events. 32 (9·9%) participants had treatment-related adverse events in the islatravir and doravirine group comapred with 38 (11·9%) in the bictegravir, emtricitabine, and tenofovir alafenamide group. In the islatravir and doravirine group, CD4 cell counts (mean change -19·7 cells per µL) and total lymphocyte counts (mean change -0·20 × 109/L) were decreased at 48 weeks. INTERPRETATION: Switching to daily doravirine (100 mg) and islatravir (0·75 mg) was non-inferior to bictegravir, emtricitabine, and tenofovir alafenamide at week 48. However, decreases in CD4 cell and total lymphocyte counts do not support the further development of once-daily doravirine (100 mg) and islatravir (0·75 mg). FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co.

Virologic Outcomes Among People Living With Human Immunodeficiency Virus With High Pretherapy Viral Load Burden Initiating on Common Core Agents.

BACKGROUND: People living with human immunodeficiency virus (PLWH) initiating antiretroviral therapy (ART) with viral loads (VLs) ≥100 000 copies/mL are less likely to achieve virologic success, but few studies have characterized real-world treatment outcomes. METHODS: ART-naive PLWH with VLs ≥100 000 copies/mL initiating dolutegravir (DTG), elvitegravir (EVG), raltegravir (RAL), or darunavir (DRV) between 12 August 2013 and 31 July 2017 were identified from the OPERA database. Virologic failure was defined as (i) 2 consecutive VLs ≥200 copies/mL after 36 weeks of ART; (ii) 1 VL ≥200 copies/mL with core agent discontinuation after 36 weeks; (iii) 2 consecutive VLs ≥200 copies/mL after suppression (≤50 copies/mL) before 36 weeks; or (iv) 1 VL ≥200 copies/mL with discontinuation after suppression before 36 weeks. Cox modeling estimated the association between regimen and virologic failure. RESULTS: There were 2038 ART-naive patients with high VL who initiated DTG (36%), EVG (46%), DRV (16%), or RAL (2%). Median follow-up was 18.1 (interquartile range, 12.4-28.9) months. EVG and DTG initiators were similar at baseline, but RAL initiators were older and more likely to be female with low CD4 cell counts while DRV initiators differed notably on factors associated with treatment failure. Virologic failure was experienced by 9.2% DTG, 13.2% EVG, 18.4% RAL, and 18.8% DRV initiators. Compared to DTG, the adjusted hazard ratio (95% confidence interval) was 1.46 (1.05-2.03) for EVG, 2.24 (1.50-3.34) for DRV, and 4.13 (1.85-9.24) for RAL. CONCLUSIONS: ART-naive PLWH with high VLs initiating on DTG were significantly less likely to experience virologic failure compared to EVG, RAL, and DRV initiators.Antiretroviral therapy-naïve people living with HIV (PLWH) initiating therapy with viral loads ≥100,000 copies/mL varied markedly at baseline. In adjusted models, PLWH initiating dolutegravir-based regimens were less likely to experience virologic failure as compared to elvitegravir, raltegravir and darunavir initiators.

Dehydration enhances cellular and humoral immunity in a mesic snake community.

The immunocompetence of a community of free-living animals can be affected by seasonality, sex, and parasite burden. However, each of these factors is often examined independently. Recent studies have also found that dehydration can enhance aspects of immunocompetence in drought-adapted species. To explore how all of these factors interact, and their effect on the immune system in mesic-adapted species, we collected blood samples from a community of free-ranging snakes in coastal South Carolina, United States, across 2 years. We specifically examined (a) how sex and seasonality influence humoral and cellular immunocompetence and parasite burden, (b) the dynamics among hydration state, parasite burden, and immunocompetence, and (c) whether mesic-adapted species also show enhanced innate immunity with dehydration. Consistent with previous work on drought-adapted species, we found that dehydration enhances multiple aspects of humoral immunity in mesic species, and we are the first to report that dehydration also enhances aspects of cellular immunocompetence. Contrary to previous results in other squamates, sex and season did not impact immunocompetence or parasite prevalence. Our results also reveal complex interactions among parasite prevalence, immunocompetence, and hydration state demonstrating that hydration state and parasitism are two ubiquitous factors that should continue to be considered in future studies examining ecoimmunological variation.

Virologic Outcomes Among ART-Naïve Individuals Initiating Dolutegravir, Elvitegravir, Raltegravir or Darunavir: An Observational Study.

INTRODUCTION: Dolutegravir (DTG), Elvitegravir (EVG), Raltegravir (RAL) and Darunavir (DRV) are commonly prescribed core agents for antiretroviral therapy (ART), and a need exists to compare their clinical effectiveness, as defined by virologic failure risks in real-world settings. METHODS: This observational analysis of a US clinical cohort consisted of ART-naïve people living with HIV (PLWH) in the OPERA database initiating DTG-, EVG-, RAL- or DRV-based regimens between August 2013 and July 2016, with follow-up to July 2017. PLWH were observed from first core agent initiation until core agent discontinuation, clinical activity cessation, death, or study end. Key outcomes included viral suppression (HIV RNA < 50 copies/mL) and confirmed virologic failure (two consecutive viral loads > 200 copies/mL or a viral load > 200 copies/mL followed by discontinuation). Association between core agent and time to virologic failure was assessed with multivariate Cox proportional hazards models. RESULTS: Overall, 4049 ART-naïve PLWH initiated EVG (47.4%), DTG (34.7%), DRV (14.6%), or RAL (3.2%). DTG and EVG initiators had generally similar baseline demographics and clinical characteristics, including race, risk of infection, baseline viral load, and baseline CD4 levels. RAL and DRV initiators were older and generally sicker than DTG initiators. During follow-up, more DTG initiators achieved virologic suppression (78.7%) compared with EVG (73.6%; p < 0.05), RAL (51.9%; p < 0.0001) and DRV (48.6%; p < 0.0001) initiators. Compared to DTG, both RAL and DRV were associated with higher rates of virologic failure, with adjusted hazard ratios (95% confidence interval) of 4.70 (3.03, 7.30) and 2.38 (1.72, 3.29), respectively. No difference was observed between EVG and DTG with an adjusted hazard ratio of 1.24 (0.94, 1.64). CONCLUSION: In this large cohort representative of PLWH in care in the US, ART-naïve PLWH prescribed DTG had better virologic outcomes than RAL and DRV, but had virologic failure risks comparable to EVG, although RAL and DRV were preferentially prescribed to sicker individuals. FUNDING: ViiV Healthcare.

ING116070: a study of the pharmacokinetics and antiviral activity of dolutegravir in cerebrospinal fluid in HIV-1-infected, antiretroviral therapy-naive subjects.

BACKGROUND: Dolutegravir (DTG), a once-daily, human immunodeficiency virus type 1 (HIV-1) integrase inhibitor, was evaluated for distribution and antiviral activity in cerebrospinal fluid (CSF). METHODS: ING116070 is an ongoing, single-arm, open-label, multicenter study in antiretroviral therapy-naive, HIV-1-infected adults. Subjects received DTG (50 mg) plus abacavir/lamivudine (600/300 mg) once daily. The CSF and plasma (total and unbound) DTG concentrations were measured at weeks 2 and 16. The HIV-1 RNA levels were measured in CSF at baseline and weeks 2 and 16 and in plasma at baseline and weeks 2, 4, 8, 12, and 16. RESULTS: Thirteen white men enrolled in the study; 2 withdrew prematurely, 1 because of a non-drug-related serious adverse event (pharyngitis) and 1 because of lack of treatment efficacy. The median DTG concentrations in CSF were 18 ng/mL (range, 4-23 ng/mL) at week 2 and 13 ng/mL (4-18 ng/mL) at week 16. Ratios of DTG CSF to total plasma concentration were similar to the unbound fraction of DTG in plasma. Median changes from baseline in CSF (n = 11) and plasma (n = 12) HIV-1 RNA were -3.42 and -3.04 log10 copies/mL, respectively. Nine of 11 subjects (82%) had plasma and CSF HIV-1 RNA levels <50 copies/mL and 10 of 11 (91%) had CSF HIV-1 RNA levels <2 copies/mL at week 16. CONCLUSIONS: The DTG concentrations in CSF were similar to unbound plasma concentrations and exceeded the in vitro 50% inhibitory concentration for wild-type HIV (0.2 ng/mL), suggesting that DTG achieves therapeutic concentrations in the central nervous system. The HIV-1 RNA reductions were similar in CSF and plasma. Clinical Trials Registration. NCT01499199.

Efficacy and safety 48 weeks after switching from efavirenz to rilpivirine using emtricitabine/tenofovir disoproxil fumarate-based single-tablet regimens.

BACKGROUND: Due to ongoing neuropsychiatric adverse events in some efavirenz (EFV)-treated patients, a switch to an alternative non-nucleoside reverse transcriptase inhibitor may be considered. Rilpivirine (RPV) has been coformulated as a single-tablet regimen (STR) with emtricitabine/tenofovir disoproxil fumarate (FTC/TDF), and the components have demonstrated noninferior efficacy to EFV+FTC/TDF, good tolerability profile, and high adherence. After discontinuation, EFV has an extended inductive effect on cytochrome P450 (CYP) 3A4 that, after switching, may reduce RPV exposures and adversely impact clinical outcomes. OBJECTIVE: This study examines the clinical implications of reduced RPV exposures with concomitant FTC/TDF and declining EFV exposures when patients, intolerant to EFV, switch from EFV/FTC/TDF to RPV/FTC/TDF. METHODS: This 48-week, phase 2b, open-label, multicenter study evaluated the efficacy and safety of switching from EFV/FTC/TDF (≥3 months duration) to RPV/FTC/TDF. Virologic suppression (HIV-1 RNA <50 copies/mL), safety, and EFV and RPV pharmacokinetics were assessed. RESULTS: At weeks 12 and 24, all 49 dosed subjects remained suppressed on RPV/FTC/TDF. At week 48, 46 (93.9%) subjects remained suppressed and virologic failure occurred in 2/49 (4.1%) subjects with no emergence of resistance. EFV concentrations were above the 90th percentile for inhibitory concentration (IC90) for several weeks after EFV discontinuation, and RPV exposures were in the range observed in phase 3 studies by approximately 2 weeks post switch. No subjects discontinued the study due to an adverse event. CONCLUSIONS: Switching from EFV/FTC/TDF to RPV/FTC/ TDF was a safe, efficacious option for virologically suppressed HIV-infected patients with EFV intolerance wishing to remain on an STR.

Once-daily darunavir/ritonavir vs. lopinavir/ritonavir in treatment-naive, HIV-1-infected patients: 96-week analysis.

OBJECTIVE: Present 96-week data from ongoing ARTEMIS (AntiRetroviral Therapy with TMC114 ExaMined In Naive Subjects) trial. METHODS: Randomized, open-label, phase III trial of antiretroviral-naive patients with HIV-1 RNA at least 5000 copies/ml (stratified by HIV-1 RNA and CD4 cell count) receiving darunavir/ritonavir (DRV/r) 800/100 mg once daily or lopinavir/ritonavir (LPV/r) 800/200 mg total daily dose (twice daily or once daily) and fixed-dose tenofovir/emtricitabine. Primary outcome measure was noninferiority of DRV/r vs. LPV/r in virologic response (<50 copies/ml, time-to-loss of virologic response) at 96 weeks (secondary outcome: superiority). RESULTS: Six hundred eighty-nine patients were enrolled. At week 96, significantly more DRV/r (79%) than LPV/r patients (71%) had viral load less than 50 copies/ml, confirming statistical noninferiority (estimated difference: 8.4%; 95% confidence interval 1.9-14.8; P < 0.001; per-protocol) and superiority (P = 0.012; intent-to-treat) in virologic response. Median CD4 cell count increases from baseline were 171 and 188 cells/microl for DRV/r and LPV/r, respectively (P = 0.57; noncompleter=failure). Overall, 4% of DRV/r patients and 9% of LPV/r patients discontinued treatment due to adverse events. Lower rates of grade 2-4 treatment-related diarrhea were seen with DRV/r (4%) vs. LPV/r (11%; P < 0.001), whereas grade 2-4 treatment-related rash occurred infrequently in both arms (3 vs. 1%, respectively; P = 0.273). DRV/r patients had smaller median increases in triglycerides (0.1 and 0.6 mmol/l, respectively, P < 0.0001) and total cholesterol (0.6 and 0.9 mmol/l, respectively; P < 0.0001) than LPV/r patients; levels remained below National Cholesterol Education Program cut-offs for DRV/r. CONCLUSION: At week 96, once-daily DRV/r was both statistically noninferior and superior in virologic response to LPV/r, with a more favorable gastrointestinal and lipid profile, confirming DRV/r as an effective, well tolerated, and durable option for antiretroviral-naive patients.

Efficacy and safety of etravirine (TMC125) in patients with highly resistant HIV-1: primary 24-week analysis.

OBJECTIVE: TMC125-C223 is an open-label, partially blinded, randomized clinical trial to evaluate the efficacy and safety of two dosages of etravirine (TMC125), a non-nucleoside reverse transcriptase inhibitor (NNRTI) with activity against wild-type and NNRTI-resistant HIV-1. DESIGN: A total of 199 patients were randomly assigned 2: 2: 1 to twice-daily etravirine 400 mg, 800 mg and control groups, respectively. The primary endpoint was a change in viral load from baseline at week 24 in the intention-to-treat population. METHODS: Patients had HIV-1 with genotypic resistance to approved NNRTIs and at least three primary protease inhibitor (PI) mutations. Etravirine groups received an optimized background of at least two approved antiretroviral agents [nucleoside reverse transcriptase inhibitors (NRTI) and/or lopinavir/ritonavir and/or enfuvirtide]. Control patients received optimized regimens of at least three antiretroviral agents (NRTIs or PIs and/or enfuvirtide). RESULTS: The mean change from baseline in HIV-1 RNA at week 24 was -1.04, -1.18 and -0.19 log10 copies/ml for etravirine 400 mg twice a day, 800 mg twice a day and the control group, respectively (P < 0.05 for both etravirine groups versus control). Etravirine showed no dose-related effects on safety and tolerability. No consistent pattern of neuropsychiatric symptoms was observed. There were few hepatic adverse events, and rashes were predominantly early onset and mild to moderate in severity. CONCLUSION: Etravirine plus an optimized background significantly reduced HIV-1-RNA levels from baseline after 24 weeks in patients with substantial NNRTI and PI resistance, and demonstrated a favorable safety profile compared with control.