Switching strategies in the recent era of antiretroviral therapy

In Situ Forming, Enzyme-Responsive Peptoid-Peptide Hydrogels: An Advanced Long-Acting Injectable Drug Delivery System

Long-acting drug delivery systems are promising platforms to improve patient adherence to medication by delivering drugs over sustained periods and removing the need for patients to comply with oral regimens. This research paper provides a proof-of-concept for the development of a new optimized in situ forming injectable depot based on a tetrabenzylamine-tetraglycine-d-lysine-O-phospho-d-tyrosine peptoid-D-peptide formulation ((NPhe)4GGGGk(AZT)y(p)-OH). The chemical versatility of the peptoid-peptide motif allows low-molecular-weight drugs to be precisely and covalently conjugated. After subcutaneous injection, a hydrogel depot forms from the solubilized peptoid-peptide-drug formulation in response to phosphatase enzymes present within the skin space. This system is able to deliver clinically relevant concentrations of a model drug, the antiretroviral zidovudine (AZT), for 35 days in Sprague-Dawley rats. Oscillatory rheology demonstrated that hydrogel formation began within ∼30 s, an important characteristic of in situ systems for reducing initial drug bursts. Gel formation continued for up to ∼90 min. Small-angle neutron scattering data reveal narrow-radius fibers (∼0.78-1.8 nm) that closely fit formation via a flexible cylinder elliptical model. The inclusion of non-native peptoid monomers and D-variant amino acids confers protease resistance, enabling enhanced biostability to be demonstrated in vitro. Drug release proceeds via hydrolysis of an ester linkage under physiological conditions, releasing the drug in an unmodified form and further reducing the initial drug burst. Subcutaneous administration of (NPhe)4GGGGk(AZT)y(p)-OH to Sprague-Dawley rats resulted in zidovudine blood plasma concentrations within the 90% maximal inhibitory concentration (IC90) range (30-130 ng mL-1) for 35 days.

Doravirine Plus Integrase Strand Transfer Inhibitors as a 2-Drug Treatment-Switch Strategy in People Living with HIV: The Real-Life DORINI Multicentric Cohort Study

BACKGROUND

Few data are available about the efficacy, durability, and tolerability of doravirine (DOR) + integrase strand inhibitors (INI) as a switching strategy among antiretroviral therapy (ART)-experienced people living with HIV (PLWH).

SETTING

Retrospective, multicenter cohort study investigating the durability, efficacy, and tolerability of 2 off-label drug associations of DOR + INI among ART-experienced PLWH.

METHODS

The study included PLWH who switched to DOR combined with either raltegravir (RAL) or dolutegravir (DTG) between June 1, 2020, and December 31, 2021, with at least 1 follow-up (FU) visit. Virologic, biometric, and metabolic parameters were evaluated at baseline (T0) and at 1-3 (T1), 6 (T2), and 12 (T3) months. Univariate and multivariate survival analyses assessed the 28-week probability of persistence on the regimens. Patient satisfaction was measured using the HIV Treatment Satisfaction Questionnaire.

RESULTS

Ninety-five PLWH were included, 52 in DOR + RAL and 43 in DOR + DTG. Six treatment discontinuations were reported during a mean of 37 (±17) weeks of FU (incidence of 2.7 × 1000 person-weeks FU). Only 2 were the result of virological failure without resistance mutations. DOR + DTG demonstrated significantly higher 28-week persistence than DOR + RAL (HR 1.90, 95% CI: 1.24-2.90, log-rank: P = 0.003). Weight, waist circumference, and fasting lipids reduced considerably at T3 vs T0. Overall, high satisfaction with the new treatment was reported, particularly in the DOR + RAL (68 (64-72)/72), compared with the DOR + DTG group (58 (50-65)/72, P < 0.001).

CONCLUSIONS

Our experience revealed few treatment discontinuations, improved metabolic parameters, and high patient satisfaction among ART-experienced PLWH switching to DOR combined with INI, irrespective of the specific INI used.

Enzyme-Triggered l-α/d-Peptide Hydrogels as a Long-Acting Injectable Platform for Systemic Delivery of HIV/AIDS Drugs

Eradicating HIV/AIDS by 2030 is a central goal of the World Health Organization. Patient adherence to complicated dosage regimens remains a key barrier. There is a need for convenient long-acting formulations that deliver drugs over sustained periods. This paper presents an alternative platform, an injectable in situ forming hydrogel implant to deliver a model antiretroviral drug (zidovudine [AZT]) over 28 days. The formulation is a self-assembling ultrashort d or l-α peptide hydrogelator, namely phosphorylated (naphthalene-2-ly)-acetyl-diphenylalanine-lysine-tyrosine-OH (NapFFKY[p]-OH), covalently conjugated to zidovudine via an ester linkage. Rheological analysis demonstrates phosphatase enzyme instructed self-assembly, with hydrogels forming within minutes. Small angle neutron scattering data suggest hydrogels form narrow radius (≈2 nm), large length fibers closely fitting the flexible cylinder elliptical model. d-Peptides are particularly promising for long-acting delivery, displaying protease resistance for 28 days. Drug release, via hydrolysis of the ester linkage, progress under physiological conditions (37 °C, pH 7.4, H2 O). Subcutaneous administration of Napffk(AZT)Y[p]G-OH in Sprague Dawley rats demonstrate zidovudine blood plasma concentrations within the half maximal inhibitory concentration (IC50 ) range (30-130 ng mL-1 ) for 35 days. This work is a proof-of-concept for the development of a long-acting combined injectable in situ forming peptide hydrogel implant. These products are imperative given their potential impact on society.

Binding Insight of Anti-HIV Phytocompounds with Prime Targets of HIV: A Molecular Dynamics Simulation Analysis

BACKGROUND

Despite intense efforts, AIDS is difficult to tackle by current anti-retroviral therapy (ART) due to its side effects; therefore, there is an urgent need to discover potential, multitarget and low-cost anti-HIV compounds.

OBJECTIVE

We have shown that few phytocompounds can potentially inhibit the prime targets of HIV namely GP120 envelope protein, reverse transcriptase, protease, integrase and ribonulcease. In this study, top ranked prioritized compounds were subjected to Molecular Dynamics (MD) simulation in order to study the conformational dynamics and integrity of crucial interaction in the receptor sites.

METHODS

The system was built for selected protein-ligand complex using TIP3P water model and OPLS_2005 force field. Trajectories were recorded up to 20 ns simulation time in Desmond module of Schrödinger software.

RESULTS

As a result of a comprehensive analysis of molecular properties and dynamics of the complexes, it has been concluded that Chebulic acid, Curcumin and Mulberroside C could be developed as envelope glycoprotein GP120 inhibitor, reverse transcriptase inhibitor and protease inhibitor respectively. However, the fluctuation of Chebulic acid with respect to integrase and ribonuclease protein was higher during the simulation.

CONCLUSION

These findings can aid in the designing of the structural properties for more effective anti-HIV compounds against the given targets.

Impact of Therapeutic Drug Monitoring of Antiretroviral Drugs in Routine Clinical Management of People Living With HIV: A Narrative Review

BACKGROUND

The treatment of HIV infection has evolved significantly since the advent of highly active antiretroviral therapy. As a result, a response rate of 90%-95% now represents a realistically achievable target. Given this background, it is difficult to imagine the additional benefits that therapeutic drug monitoring (TDM) could provide in the management of HIV infection.

METHODS

This article is not intended to provide a systematic literature review on TDM of antiretroviral agents; rather, the authors aim to discuss the potential added value of TDM in the optimal management of people living with HIV (PLWH) in selected real-life clinical scenarios based on data collected over 10 years by their TDM service.

RESULTS

Some clinical situations, in which the selection of the optimal antiretroviral therapy is challenging, have been identified. These include poorly compliant patients, suboptimal antiretroviral therapies (in terms of both efficacy and toxicity), polypharmacy with a high risk of drug-drug interactions, and different patient populations, such as pregnant women.

CONCLUSIONS

The transformation of HIV infection from a near-universally fatal illness to a lifelong chronic disease has resulted in an HIV population that is growing and aging, placing new and increasing demands on public programs and health services. Increasingly, the management of comorbidities, polypharmacy, and drug-drug interaction, and their impact on antiretroviral therapy will have to be undertaken. These clinical settings represent some of the new frontiers for the use of TDM with the goal of achieving optimal prescription and outcome for PLWH.

Recent Advances in the Development of Integrase Inhibitors for HIV Treatment

PURPOSE OF THE REVIEW

The complex multistep life cycle of HIV allows it to proliferate within the host and integrate its genome in to the host chromosomal DNA. This provirus can remain dormant for an indefinite period. The process of integration, governed by integrase (IN), is highly conserved across the Retroviridae family. Hence, targeting integration is not only expected to block HIV replication but may also reveal new therapeutic strategies to treat HIV as well as other retrovirus infections.

RECENT FINDINGS

HIV integrase (IN) has gained attention as the most promising therapeutic target as there are no equivalent homologues of IN that has been discovered in humans. Although current nano-formulated long-acting IN inhibitors have demonstrated the phenomenal ability to block HIV integration and replication with extraordinary half-life, they also have certain limitations. In this review, we have summarized the current literature on clinically established IN inhibitors, their mechanism of action, the advantages and disadvantages associated with their therapeutic application, and finally current HIV cure strategies using these inhibitors.

Long-term efficacy and safety of nevirapine-containing regimens in virologically suppressed patients: a 17-year follow up

Background: To evaluate long term outcomes in patients maintaining a NVP based regimen for more than 10 years.Materials and methods: Retrospective, multicenter, cohort study including virologically suppressed patients, currently receiving a NVP-based regimen that had been started at least 10 years previously. Demographic, clinical, and analytical variables were recorded.Results: Two hundred and seventy four subjects were included. Median (IQR) follow up was 17.1 (13.8-18.5) years. Dyslipidemia (29.9%), hypertension (11.4%) and diabetes (8%) were the most common reported co-morbidities. After a median of 17 years of follow-up we observed a significant increase in general health markers such as hemoglobin and CD4 cells (all p<0.001) as well as a significant reduction in CD8 and ALT [-111 cells/uL (-346.5-151) p 0.003 and ALT median (IQR) -4.2 (-18.5-4) p<0.001 respectively]. LDL-c and serum triglyceride levels decreased significantly [-0,1 (-1-0.6) p:<0.001 and -0,3 (-1.2-0.4) p:0.002 respectively]. HDL-c increased significantly 0.3 (00.5-0.6). Median (IQR) time with persistent HIV VL <50 copies was 16 (13-18) years. During follow up, subjects presented with median (IQR) 1 (0-2) blip (HIV VL >50<1000 copies/ml).Conclusions: Based on the extensive experience as well as a good tolerance and efficacy profile, NVP should be considered for treatment continuation in those patients already receiving this inexpensive generic drug.

Virological Outcome After Choice of Antiretroviral Regimen Guided by Proviral HIV-1 DNA Genotyping in a Real-Life Cohort of HIV-Infected Patients

Issues have been raised concerning clinical relevance of HIV-1 proviral DNA genotypic resistance test (DNA GRT). To assess impact of DNA GRT on choice of antiretroviral therapy (ART) and subsequent virological outcome, we retrospectively reviewed decision-making and viral load (VL) evolution following DNA GRT performed in our center between January 2012 and December 2017, except those prescribed within the framework of a clinical trial. A total of 304 DNA GRTs were included, 185 (62%) performed in a context of virological success. Only 34% of tests were followed by ART change, more frequently in situation of virological success (39% vs. 26%, p = 0.02). In this situation, ART change guided by DNA GRT led to VL >20 copies/mL after 6 months in 5% of cases. In multivariate analysis, higher HIV DNA quantification (p = 0.01) was associated with occurrence of viremia. A higher nadir of CD4 count (p = 0.04) and a longer time with VL <20 copies/mL (p = 0.04) were independently associated with a lower risk of viremia. In situation of low-level viremia, ART change guided by DNA GRT led to VL <20 copies/mL after 6 months in 52% of cases, while decision to maintain the same treatment led to VL <20 copies/mL in 74% of cases. In multivariate analysis, longer time with VL >20 copies/mL (p = 0.02) was associated with persistence of virological replication. In conclusion, in situation of virological success, use of DNA GRT in addition to analysis of historical RNA GRT to guide ART optimization appears safe. Its prescription framework in situation of low-level viremia deserves to be better defined.

Positioning of darunavir/cobicistat-containing antiretroviral regimens in real life: results from a large multicentre observational prospective cohort (SCOLTA)

Background

Study aim was to evaluate the safety and durability of darunavir/cobicistat (DRV/c) in a real life setting.

Methods

Multicentre prospective cohort study performed in the context of SCOLTA (Surveillance Cohort Long-Term Toxicity Antiretrovirals). Patients were evaluated at baseline, week 24 and 48. Changes were evaluated using the paired t test or signed rank test. The multivariable analysis was performed using a general linear model, after ranking of not normally distributed variables.

Results

A total of 249 patients were included, 72 (29%) were in DRV/c-based dual therapies (DT). Hypercholesterolemia, HC, (total cholesterol (TC) ≥ 200 mg/dL or low density-C (LDL-C) ≥ 130 or statin use) was present in 121 (48.6%) and hypertriglyceridemia, (triglycerides (TG) ≥ 200 mg/dl or fibrate use) in 41 (16.5%) patients. Blood lipid profile did not change significantly in either the global population or patients with HC. After a median observation of 17 months (IQR 13–20), 59 (25.3%) patients discontinued DRV/c, of which 13 were in DT. The durability DT resulted higher than that of triple therapy (log-rank test p = 0.01). Main reasons for stopping DRV/c were simplification (15 patients), adverse events (13 patients), planned discontinuation for treatment initiation with DAA (4 patients), treatment failure (2 patients); death (2 patients), other causes (10 patients). Twenty-six were lost to follow-up.

Conclusions

DRV/c was safe and well tolerated. Dual therapies showed a better profile of tolerability and a longer durability compared to triple therapies.