No Changes in Human Immunodeficiency Virus (HIV) Suppression and Inflammatory Markers in Cerebrospinal Fluid in Patients Randomly Switched to Dolutegravir Plus Lamivudine (Spanish HIV/AIDS Research Network, PreEC/RIS 62)

Two-drug regimens for HIV treatment

Combination therapy with three antiretroviral agents has been integral to successful HIV-1 treatment since 1996. Although the efficacy, adverse effects, and toxicities of contemporary three-drug regimens have improved, even the newest therapies have potential adverse effects. The use of two-drug regimens is one way to reduce lifetime exposure to antiretroviral drugs while maintaining the benefits of viral suppression. Multiple large, randomised trials have shown the virological non-inferiority of certain two-drug regimens versus three-drug comparators, including adverse effect differences that reflect known profiles of the antiretroviral drugs in the respective regimens. Two-drug combinations are now recommended in treatment guidelines and include the first long-acting antiretroviral regimen for the treatment of HIV-1. Recommended two-drug regimens differ in their risks for, and factors associated with, virological failure and emergent resistance. The tolerability, safety, metabolic profiles, and drug interactions of two-drug regimens also vary by the constituent drugs. No current two-drug regimen is recommended for people with chronic hepatitis B virus as none include tenofovir. Two-drug regimens have increased options for individualised care.

Qualitative study exploring the experiences and perceptions of dolutegravir/lamivudine dual antiretroviral therapy (the PEDAL study) in people living with HIV: protocol

INTRODUCTION

Antiretroviral treatment turned HIV infection into a chronic disease and improved quality of life for people living with HIV. Dual-drug combinations have been shown to be effective in suppressing viral replication and can potentially reduce long-term drug-associated toxicities. We aim to investigate patients' perceptions and experiences on the safety, effectiveness, tolerability and unmet needs of the dual-drug combination dolutegravir/lamivudine in Brighton and Hove, UK. In addition, we will conduct a comparative analysis between patients on dolutegravir/lamivudine and patients on other dual-drug and three-drug combinations. Finally, the study aims to provide recommendations to improve doctor-patient communication, knowledge and understanding of the treatment plan, and additional care that ought to be considered in patient-centred, holistic care plans.

METHODS AND ANALYSIS

Our qualitative methodological framework is based on three main methods: cultural domain analysis, focus group discussions and in-depth interviews. Cultural domain analysis employs a range of techniques (free listing, pile sorts and rankings) to elicit terms from informants regarding specific cultural domains (ie, groups of items that are perceived to be of the same kind). This framework has been codesigned with a patient representative to ensure relevance, suitability and coproduction of knowledge. All methods have been tested to take place online, as an option, via Zoom, Skype or Microsoft Teams. Padlet, an application to create online boards, will be used during the cultural domain analysis session. Data collected will be analysed following the completion of each method embracing an iterative approach through applied thematic analysis.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Health Research Authority (Reference 21/NW/0070). Findings will be used to produce recommendations to improve doctor and patient communication by identifying patients' fears, worries, misconceptions and general concerns of their drug regimen. Conclusions will be disseminated via journal articles, conference papers and discussions through public engagement events.

PROJECT REGISTRATION NUMBER

IRAS number: 286277. NCT04901728.

Changes in Inflammatory and Atherogenesis Biomarkers With the 2-Drug Regimen Dolutegravir Plus Lamivudine in Antiretroviral Therapy–Experienced, Virologically Suppressed People With HIV-1: A Systematic Literature Review

Background

The 2-drug regimen dolutegravir plus lamivudine has demonstrated long-term noninferior efficacy vs 3-/4-drug regimens (3/4DRs) in phase 3 trials. This systematic literature review summarizes clinical trial and real-world evidence evaluating impact of dolutegravir plus lamivudine on inflammatory and atherogenesis biomarkers in people with human immunodeficiency virus type 1 (PWH).

Methods

Using Ovid MEDLINE, Embase, PubMed, and Cochrane library databases and conference proceedings, we searched for studies published from 1 January 2013 to 14 July 2021, reporting changes in inflammatory and atherogenesis biomarkers with dolutegravir plus lamivudine in antiretroviral therapy–experienced, virologically suppressed PWH aged ≥18 years.

Results

Four records representing 2 randomized controlled trials (RCTs) and 6 records of real-world evidence met eligibility criteria. All real-world studies evaluated CD4⁺/CD8⁺ ratio, while only 1 assessed inflammatory biomarkers. Across both RCTs, no consistent pattern of change in biomarkers was observed between dolutegravir/lamivudine and 3/4DR comparators. There were significant changes in soluble CD14 favoring dolutegravir/lamivudine in TANGO at weeks 48 and 144 and SALSA at week 48, and in interleukin-6 favoring the control group in TANGO at weeks 48 and 144. In the real-world study evaluating inflammatory biomarkers, median soluble CD14 significantly decreased 48 weeks postswitch to dolutegravir plus lamivudine (P < .001), while other biomarkers remained stable. In all 6 real-world studies, increases in CD4⁺/CD8⁺ ratio were reported after switch to dolutegravir plus lamivudine (follow-up, 12–60 months).

Conclusions

Results show that dolutegravir plus lamivudine has a comparable impact on inflammatory and atherogenesis biomarkers vs 3/4DRs, with no consistent pattern of change after switch in virologically suppressed PWH.

Cerebrospinal fluid exposure to bictegravir/emtricitabine/tenofovir in HIV-1-infected patients with CNS impairment

OBJECTIVES

The penetration of antiretroviral drugs into deep compartments, such as the CNS, is a crucial component of strategies towards an HIV cure. This study aimed to determine CSF concentrations of bictegravir, emtricitabine and tenofovir in patients with HIV-related CNS impairment (HCI) enrolled in a real-life observational study.

METHODS

Patients with HCI treated by optimized ART, including bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) for at least 1 month were enrolled. Plasma and CSF concentrations were measured by quality control-validated assays (LC-MS/MS). The inhibitory quotient (IQARV) was calculated as the ratio of unbound (bictegravir) or total (emtricitabine and tenofovir) concentration to half (or 90%) maximal inhibitory concentration for bictegravir (or emtricitabine and tenofovir). All numerical variables are expressed as median (range).

RESULTS

Twenty-four patients (nine women) were enrolled. The age was 45 (26-68) years. Unbound bictegravir and total emtricitabine and tenofovir CSF concentrations were 4.4 (1.6-9.6), 84.4 (28.6-337.4) and 1.6 (0.7-4.3) ng/mL, respectively. The unbound bictegravir CSF fraction was 34% (15%-82%) versus 0.33% (0.11%-0.92%) in plasma. Three patients had an IQARV above unity for the three antiretrovirals. Factors positively associated with the CSF concentration (unbound for bictegravir) were age and total plasma concentration for the three antiretrovirals. Patients aged over 51 years had higher CSF concentrations (unbound for bictegravir).

CONCLUSIONS

We observed low CSF exposure to bictegravir, emtricitabine and tenofovir. These results suggest that BIC/FTC/TAF should be used with caution as first-line treatment for people living with HIV with HCI under 51 years of age.

CNS Considerations in ART Simplification Strategies

PURPOSE OF THE REVIEW

This review summarizes current knowledge on central nervous system (CNS) considerations in ART simplification strategies.

RECENT FINDINGS

Antiretroviral therapies (ART) showing efficacy in plasma will usually show efficacy in the cerebrospinal fluid (CSF). ART simplification may virologically fail if the new regimen has less than two active drugs, the genetic barrier of drugs is not high, and the patient may harbour archived resistance. Dual therapies including a boosted protease inhibitor (PI) or dolutegravir (DTG) are generally effective from the CNS perspective. In cases of related neurotoxicity, switching from either efavirenz (EFV) or DTG to another equally effective drug with better CNS tolerability usually leads to complete resolution of CNS symptoms. However, improvement may be incomplete when factors other than ART that cannot be easily modified are involved.

Doravirine Achieves Adequate CSF Exposure and is Mostly Unbound to Proteins

We determined total and unbound concentrations of Doravirine (DOR) in cerebrospinal fluid (CSF) and blood plasma. Total and unbound DOR concentrations in CSF exceeded the EC50 value against wild-type virus (5.1 ng/mL) in all subjects suggesting that DOR may contribute to inhibit viral replication in this compartment.

Efficacy and safety of switching to dolutegravir plus lamivudine versus continuing triple antiretroviral therapy in virologically suppressed adults with HIV at 48 weeks (DOLAM): a randomised non-inferiority trial

BACKGROUND

Simplified antiretroviral therapy (ART) regimens are desirable for people with HIV. We investigated the efficacy and safety of switching from triple ART to dual dolutegravir plus lamivudine therapy.

METHODS

DOLAM is a phase 4, randomised, open-label, non-inferiority trial, done at six HIV clinics in Catalonia, Spain. Adults with HIV-1 receiving a triple ART regimen, aged 18 years or older, with virological suppression, a CD4 nadir of at least 200 cells per μL, who were HBsAg-negative, and without previous viral failure or resistance mutations to study drugs were eligible. Participants underwent computer-generated randomisation, stratified by the class of the third drug, and were assigned (1:1) to switch to oral dolutegravir 50 mg and lamivudine 300 mg once daily or to continue triple ART for 48 weeks. The primary endpoint was the proportion of people with an HIV RNA value of at least 50 copies per mL at week 48 (US Food and Drug Administration snapshot algorithm, 8% non-inferiority margin). Both the primary and safety outcomes were evaluated in the intention-to-treat exposed population. The study is completed and was registered with EudraCT 201500027435.

FINDINGS

Between July 7, 2015, and Oct 31, 2018, 265 participants were randomly assigned to switch to dolutegravir plus lamivudine (n=131) or to maintain triple ART (n=134) and all received at least one dose. Nine (7%) participants in the dual therapy group and ten (7%) in the triple therapy group were excluded before 48 weeks, mostly due to treatment discontinuations or virological failure. Participants were predominantly male (116 [87%] of 134 in the triple ART group and 111 [85%] of 131 in the dolutegravir plus lamivudine group). The difference in the proportion of participants with HIV RNA values of at least 50 copies per mL at 48 weeks between the dual therapy group (three [2%] of 131) and triple therapy group (two [1%] of 134) was 0·8 percentage points (95% CI -3·3 to 5·2), showing non-inferiority of dolutegravir plus lamivudine dual therapy compared with triple ART. 73 (56%) of 131 participants allocated to dual therapy had 150 adverse effects, compared with 78 (58%) of 134 participants allocated to triple therapy who also had 150 adverse events (p=0·68). Drug discontinuation due to adverse effects occurred in four people in the triple therapy group and three people in the dual therapy group.

INTERPRETATION

Our findings show the efficacy and safety of dolutegravir plus lamivudine as a simplified therapy switch option for selected people with HIV with virological suppression on triple ART.

FUNDING

Instituto de Salud Carlos III, Red de Investigación en Sida, and ViiV Healthcare.