UNASSIGNED: We aimed to determine the effectiveness of switching to bictegravir in maintaining an undetectable viral load (<50 copies/mL) among people with HIV (PWH) as compared with continuing dolutegravir-, efavirenz-, or raltegravir-based antiretroviral therapy using nationwide observational data from Mexico.
UNASSIGNED: We emulated 3 target trials comparing switching to bictegravir vs continuing with dolutegravir, efavirenz, or raltegravir. Eligibility criteria were PWH aged ≥16 years with a viral load <50 copies/mL and at least 3 months of current antiretroviral therapy (dolutegravir, efavirenz, or raltegravir) between July 2019 and September 2021. Weekly target trials were emulated during the study period, and individuals were included in every emulation if they continued to be eligible. The main outcome was the probability of an undetectable viral load at 3 months, which was estimated via an adjusted logistic regression model. Estimated probabilities were compared via differences, and 95% CIs were calculated via bootstrap. Outcomes were also ascertained at 12 months, and sensitivity analyses were performed to test our analytic choices.
UNASSIGNED: We analyzed data from 3 028 619 PWH (63 581 unique individuals). The probability of an undetectable viral load at 3 months was 2.9% (95% CI, 1.9%-3.8%), 1.3% (95% CI, .9%-1.6%), and 1.2% (95% CI, .8%-1.7%) higher when switching to bictegravir vs continuing with dolutegravir, efavirenz, and raltegravir, respectively. Similar results were observed at 12 months and in other sensitivity analyses.
UNASSIGNED: Our findings suggest that switching to bictegravir could be more effective in maintaining viral suppression than continuing with dolutegravir, efavirenz, or raltegravir.

We describe and analyze resistance-associated mutations (RM) and virological failures (VF) on antiretroviral therapy using the latest approved integrase inhibitors (INIs) dolutegravir (DTG), bictegravir (BIC), and cabotegravir (CAB), together with their companion drugs in fixed-dose formulations: BIC/emtricitabine/tenofovir; CAB/rilpivirine; DTG/abacavir/lamivudine; DTG/emtricitabine/tenofovir; and DTG/lamivudine. Systematic literature searches were conducted in PubMed and other electronic databases for clinical studies published between January 2010 and May 2023, according to preferred reporting items for systematic reviews and meta-analyses guidelines (PRISMA), which analyzed VFs and RMs of INIs. Fifty clinical studies were included in the synthesis. VF in antiretroviral treatment (ART)-naïve patients occurred in 0.7-4.0%, 0.6-1.4%, and 0.6-9.0% of patients treated with DTG, BIC, and CAB, respectively. VF was reported in patients with previous ART in 0-8.1%, 0-2.0%, and 0.4-2.3% of those treated with DTG, BIC, and CAB, respectively. RMs were detected in ART-naïve patients in only one study with DTG (0.3%), none of the studies with BIC, and three of the studies with CAB (0.1-5.4%). In ART-experienced patients, RMs were detected in 0-1.9% of DTG-treated patients. No cases of RM were detected in the 11 BIC studies reviewed. In the case of CAB, RMs were detected in eight studies, ranging from 0.3% to 1.9% of patients. In conclusion, RM rates in the studies reviewed were generally low using the latest INIs. This review identified BIC as the INI with the lowest number of observed VF and lack of RM.

Integrase strand transfer inhibitors (INSTIs) based antiretroviral therapy (ART) is currently used as first-line regimen to treat HIV infection. Despite its high efficacy and barrier to resistance, ART-associated neuropsychiatric adverse effects remain a major concern. Recent studies have identified a potential interaction between the INSTI, dolutegravir (DTG), and folate transport pathways at the placental barrier. We hypothesized that such interactions could also occur at the two major blood-brain interfaces: blood-cerebrospinal fluid barrier (BCSFB) and blood-brain barrier (BBB). To address this question, we evaluated the effect of two INSTIs, DTG and bictegravir (BTG), on folate transporters and receptor expression at the mouse BCSFB and the BBB in vitro, ex vivo and in vivo. We demonstrated that DTG but not BTG significantly downregulated the mRNA and/or protein expression of folate transporters (RFC/SLC19A1, PCFT/SLC46A1) in human and mouse BBB models in vitro, and mouse brain capillaries ex vivo. Our in vivo study further revealed a significant downregulation in Slc19a1 and Slc46a1 mRNA expression at the BCSFB and the BBB following a 14-day DTG oral treatment in C57BL/6 mice. However, despite the observed downregulatory effect of DTG in folate transporters/receptor at both brain barriers, a 14-day oral treatment of DTG-based ART did not significantly alter the brain folate level in animals. Interestingly, DTG treatment robustly elevated the mRNA and/or protein expression of pro-inflammatory cytokines and chemokines (Cxcl1, Cxcl2, Cxcl3, Il6, Il23, Il12) in primary cultures of mouse brain microvascular endothelial cells (BBB). DTG oral treatment also significantly upregulated proinflammatory cytokines and chemokine (Il6, Il1β, Tnfα, Ccl2) at the BCSFB in mice. We additionally observed a downregulated mRNA expression of drug efflux transporters (Abcc1, Abcc4, and Abcb1a) and tight junction protein (Cldn3) at the CP isolated from mice treated with DTG. Despite the structural similarities, BTG only elicited minor effects on the markers of interest at both the BBB and BCSFB. In summary, our current data demonstrates that DTG but not BTG strongly induced inflammatory responses in a rodent BBB and BCSFB model. Together, these data provide valuable insights into the mechanism of DTG-induced brain toxicity, which may contribute to the pathogenesis of DTG-associated neuropsychiatric adverse effect.

Human immunodeficiency virus (HIV) continues to pose a serious threat to global health. Oral preexposure prophylaxis (PrEP), considered highly effective for HIV prevention, is the utilisation of antiretroviral (ARV) drugs before HIV exposure in high-risk uninfected individuals. However, ARV drugs are associated with poor patient compliance and pill fatigue due to their daily oral dosing. Therefore, an alternative strategy for drug delivery is required. In this work, two dissolving microneedle patches (MNs) containing either bictegravir (BIC) or tenofovir alafenamide (TAF) solid drug nanoparticles (SDNs) were developed for systemic delivery of a novel ARV regimen for potential HIV prevention. According to ex vivo skin deposition studies, approximately 11% and 50% of BIC and TAF was delivered using dissolving MNs, respectively. Pharmacokinetic studies in Sprague Dawley rats demonstrated that BIC MNs achieved a long-acting release profile, maintaining the relative plasma concentration above the 95% inhibitory concentration (IC95) for 3 weeks. For TAF MNs, a rapid release of drug and metabolism of TAF into TFV were obtained from the plasma samples. This work has shown that the proposed transdermal drug delivery platform could be potentially used as an alternative method to systemically deliver ARV drugs for HIV PrEP.

OBJECTIVE: The main objective was to compare the persistence between dolutegravir/lamivudine (DTG/3TC) and bictegravir/emtricitabine/tenofovir-alafenamide (BIC/FTC/TAF) and to analyze reasons for discontinuation.
METHODS: We conducted a retrospective, non-interventional, descriptive, and longitudinal study. All human immunodeficiency virus (HIV) patients over 18 years treated with DTG/3TC or BIC/FTC/TAF in our center were included. Persistence after first year was compared using the χ2 test. Kaplan-Meier survival analysis was performed.
RESULTS: Three hundred fifty-eight patients were included. 99.5% versus 90.99% of patients were persistent after the first year for DTG/3TC and BIC/FTC/TAF respectively (p=.001). Persistence with DGT/3TC was 1237 days (IC95% 1216-1258) and persistence with BIC/FTC/TAF was 986 days [(IC95% 950-1021); p<.001]. The difference was remained after adjusting for covariates with the cox regression model [HR=8.2 (IC95% 1.03-64.9), p=.047]. The main reasons for discontinuation for BIC/FTC/TAF were toxicity/tolerability.
CONCLUSIONS: In our study, patients have a high persistence. Patients on DTG/3TC treatment are more persistent compared to BIC/FTC/TAF, although BIC/FTC/TAF have worse baseline characteristics. The main reason for discontinuation of BIC/FTC/TAF is tolerability/toxicity.

BACKGROUND: Studies on switching to tenofovir alafenamide (TAF)-based regimens raise concerns about a worse metabolic profile in people with HIV, even though most received tenofovir disoproxil fumarate (TDF) in their previous regimen. This study aims to evaluate changes in lipid fractions, glucose, and serum markers for hepatic steatosis (HS) after switching from a TDF- or TAF-sparing regimen to bictegravir/emtricitabine/TAF (B/F/TAF).
METHODS: We performed a retrospective cohort study of people with HIV who switched to B/F/TAF from TDF- or TAF-sparing regimens between January 2019 and May 2022 with at least 6 months of follow-up. The primary endpoint was the absolute change in lipid fractions at 6 months. Secondary outcomes were changes in lipid fractions at 12 months and changes in other metabolic parameters (glucose, creatinine, and HS based on the triglyceride-to-glucose [TyG] ratio at 6 and 12 months). Changes were analysed using mixed linear regression models with random intercept and time as a fixed effect.
RESULTS: The study included 259 people with HIV (median age 55 [interquartile range (IQR) 47-60] years; 80% male; 88% Caucasian; CD4+ T-cell count 675 [IQR 450-880] cells/mm3; 84.3% HIV-RNA <50 copies/mL). In total, 63 patients (30%) had hypertension, 93 (44%) dyslipidaemia, 30 (14%) diabetes, and 45% obesity/overweight. Most (60%) switched from integrase inhibitor-based regimens, and 21% switched from a boosted regimen. At 6 months, significant reductions were observed in total cholesterol (-7.64 mg/dL [95% confidence interval (CI) -13.52 to -1.76; p = 0.002]), triglycerides (-23.4 [95% CI -42.07 to -4.65]; p = 0.003), and TyG ratio (-0.14 [95% CI -0.23 to -0.05]; p < 0.001).
CONCLUSIONS: In our real-life cohort, the effect of switching TDF-/TAF-sparing regimens to triple therapy with B/F/TAF improved total cholesterol, triglycerides, and serum markers of HS at 6 months and was neutral for the remaining metabolic parameters at 12 months.

UNASSIGNED: Antiretrovirals have the potential to cause drug interactions leading to inefficacy or toxicity via induction of efflux transporters through nuclear receptors, altering drug concentrations at their target sites.
UNASSIGNED: This study used molecular dynamic simulations and qRT-PCR to investigate bictegravir\'s interactions with nuclear receptors PXR and CAR, and its effects on efflux transporters (P-gp, BCRP, MRP1) in rat PBMCs. PBMC/plasma drug concentrations were measured using LC-MS/MS to assess the functional impact of transporter expression.
UNASSIGNED: Bictegravir significantly increased the expression of ABC transporters, with Car identified as a key mediator. This suggests that bictegravir\'s influence on nuclear receptors could affect drug transport and efficacy at the cellular level.
UNASSIGNED: Bictegravir activates nuclear receptors enhancing efflux transporter expression. Understanding these interactions is crucial for preventing drug-drug interactions and reducing toxicity in clinical use. Combining CAR antagonists with bictegravir may prevent drug resistance and toxicity. However, these findings are based on preclinical data and necessitate further clinical trials to confirm their applicability in clinical settings.

The field of retroviral integration research has a long history that started with the provirus hypothesis and subsequent discoveries of the retroviral reverse transcriptase and integrase enzymes. Because both enzymes are essential for retroviral replication, they became valued targets in the effort to discover effective compounds to inhibit HIV-1 replication. In 2007, the first integrase strand transfer inhibitor was licensed for clinical use, and subsequently approved second-generation integrase inhibitors are now commonly co-formulated with reverse transcriptase inhibitors to treat people living with HIV. International meetings specifically focused on integrase and retroviral integration research first convened in 1995, and this paper is part of the Viruses Special Issue on the 7th International Conference on Retroviral Integration, which was held in Boulder Colorado in the summer of 2023. Herein, we overview key historical developments in the field, especially as they pertain to the development of the strand transfer inhibitor drug class. Starting from the mid-1990s, research advancements are presented through the lens of the international conferences. Our overview highlights the impact that regularly scheduled, subject-specific international meetings can have on community-building and, as a result, on field-specific collaborations and scientific advancements.

OBJECTIVE: Multiple strategies have been utilised to reduce the incidence of HIV, including PrEP and rapid antiretroviral therapy initiation. The study objectives were to evaluate the efficacy, safety, satisfaction, treatment adherence, and system retention obtained with rapid initiation of bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) in naïve patients.
METHODS: This phase IV, multicenter, open-label, single-arm, 48-week clinical trial enrolled patients between January 2020 and June 2022. Adherence to treatment was evaluated with the SMAQ questionnaire and patient satisfaction with the EQ-5D.
RESULTS: Two hundred eight participants were enrolled with mean age of 35.6 years; 87.6% were males; mean CD4 count was 393.5 cells/uL (<200 cells/uL in 22.1%); viral load log was 5.6 (VL>100 000 cop/mL in 43.3%); 22.6% had AIDS, and 4.3% were coinfected with HBV. BIC/FTC/TAF was initiated on the day of their first visit to the HIV specialist in 98.6% of participants, and 9.6% were lost to follow-up. The efficacy at week 48 was 84.1 % by intention-to- treat (ITT), 94.6% by modified ITT, and 98.3% by per protocol analysis. The regimen was discontinued in two subjects (0.9%) during week 1 for grade 3 adverse events. Treatment adherence (weeks 4 [90%, IQR: 80-99%] vs. 48 [90%, IQR: 80-95%; P = 0.49]) and patient satisfaction (weeks 4 [90%, IQR: 80-99%] vs. 48 [90%, IQR: 80-95 P = 0.49]) rates were very high over the 48- week study period.
CONCLUSIONS: BIC/FTC/TAF is an appropriate option for rapid ART initiation in naïve HIV patients, offering high efficacy, safety, durability, treatment adherence, retention in the healthcare system, and patient satisfaction. Number Clinical Trial registration: NCT06177574.

OBJECTIVE: The main objective was to compare the persistence between dolutegravir/lamivudine (DTG/3TC) and bictegravir/emtricitabine/tenofovir-alafenamide (BIC/FTC/TAF) and to analyze reasons for discontinuation.
METHODS: We conducted a retrospective, non-interventional, descriptive and longitudinal study. All human immunodeficiency virus (HIV) patients over 18 years treated with DTG/3TC or BIC/FTC/TAF in our center were included. Persistence after first year was compared using the χ2 test. Kaplan-Meier survival analysis was performed.
RESULTS: Three hundred fifty-eight patients were included. 99.5% versus 90.99% of patients were persistent after the first year for DTG/3TC and BIC/FTC/TAF respectively (p = 0.001). Persistence with DGT/3TC was 1,237 days (IC95% 1,216-1,258) and persistence with BIC/FTC/TAF was 986 days ([IC95% 950-1,021]; p < 0.001). The difference was remained after adjusting for covariates with the cox regression model (HR= 8.2 [IC95% 1.03-64.9], p = 0.047). The main reasons for discontinuation for BIC/FTC/TAF were toxicity/tolerability.
CONCLUSIONS: In our study patients had a high persistence. Patients on DTG/3TC treatment were more persistent compared to BIC/FTC/TAF, although BIC/FTC/TAF have worse baseline characteristics. The main reason for discontinuation of BIC/FTC/TAF was tolerability/toxicity.