Interaction of CYP3A4 with the inhibitor cobicistat: Structural and mechanistic insights and comparison with ritonavir.

Cobicistat is a derivative of ritonavir marketed as a pharmacoenhancer for anti-HIV therapy. This study investigated the interaction of cobicistat with the target protein, drug-metabolizing cytochrome P450 3A4 (CYP3A4), at the molecular level using spectral, kinetic, functional, and structural approaches. It was found that, similar to ritonavir, cobicistat directly coordinates to the heme via the thiazole nitrogen but its affinity and the binding rate are 2-fold lower: 0.030 µM and 0.72 s-1, respectively. The newly determined 2.5 Å crystal structure of cobicistat-bound CYP3A4 suggests that these changes arise from the inability of cobicistat to H-bond to the active site S119 and establish multiple stabilizing contacts with the F-F' connecting fragment, which becomes disordered upon steric clashing with the bulky morpholine moiety. Nonetheless, cobicistat inhibits recombinant CYP3A4 as potently as ritonavir (IC50 of 0.24 µM vs 0.22 µM, respectively) due to strong ligation to the heme and formation of extensive hydrophobic/aromatic interactions via the phenyl side-groups. To get insights into the inhibitory mechanism, the K257 residue, known to be solely and irreversibly modified by the reactive ritonavir metabolite, was substituted with alanine. Neither this nor control K266A mutation changed the extent of time-dependent inhibition of CYP3A4 by cobicistat and ritonavir, suggesting the existence of alternative inactivation mechanism(s). More importantly, K257 was found to be functionally important and contributed to CYP3A4 allosterism, possibly by modulating protein-ligand interactions through conformational dynamics.

Assessment of swallowability and acceptability of scored darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) fixed-dose combination (FDC) tablets in HIV-1-infected children aged ≥6 to <12 years, using matching placebo tablets: A randomized study.

BACKGROUND: Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) fixed-dose combination (FDC) was developed as a once-daily, complete antiretroviral (ARV) regimen therapy to address the need for simplified protease inhibitor-based ARV regimens. This study assessed the swallowability and acceptability for long-term use of scored placebo tablets matching the D/C/F/TAF FDC tablets in children living with HIV-1. METHODS: This study (NCT04006704) was a Phase 1, open-label, randomized, single-dose, 2-period, 2-sequence crossover study in children living with HIV-1, aged ≥6 to <12 years and weighing ≥25 to <40 kg, on a stable ARV regimen for ≥3 months. Participants were asked to swallow whole (size, 21 × 11 × 7 mm) and split matching placebo D/C/F/TAF tablets. Swallowability of the matching placebo D/C/F/TAF tablets (primary endpoint) was assessed by observers. Acceptability of taking matching placebo D/C/F/TAF tablets and current ARVs was evaluated by participants using a 3-point questionnaire. Participants rated the acceptability for long-term daily use of the placebo D/C/F/TAF tablets, and observers assessed how easily caregivers could split a scored tablet by hand, using 3-point questionnaires. RESULTS: Among the 24 participants who enrolled and completed the study, 95.8% (23/24) were able to swallow the whole and split matching placebo D/C/F/TAF tablets after 1 or 2 attempts. Most participants (>70%) rated the acceptability of tablets for long-term daily use as acceptable or good to take. Breaking the tablets was considered easy or OK by 79.2% (19/24) of caregivers. CONCLUSION: Scored D/C/F/TAF FDC tablets are swallowable - with whole favoured over split - and considered at least acceptable for long-term daily intake in children living with HIV-1 aged ≥6 to <12 years. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04006704.

PRESTIGIO RING "a 59-year-old man with multidrug resistant HIV-1 infection failing a regimen including dolutegravir, rilpivirine, atazanavir/cobicistat: successful treatment tailoring based on genotypic and phenotypic resistance tests".

Management of virological failure in heavily treatment-experienced people with multidrug-resistant (MDR) HIV infection is a serious clinical challenge. New drugs with novel mechanisms of action have recently been approved, and their use has improved the outcome of subjects with limited treatment options (LTO). In this setting, the choice of antiretroviral therapy (ART) should be tailored based on the pattern of resistance, treatment history and patients' individual characteristics. While genotypic resistance testing is the reference method for analysing residual drug susceptibility, phenotypic resistance testing can provide additional support when facing LTO. Herein, we present the case of a patient with MDR HIV-1 infection on virological failure enrolled in the PRESTIGIO Registry. The salvage ART regimen, which included drugs with novel mechanisms of action (MoA), was tailored to the patient's clinical characteristics and on the resistance pattern explored with genotypic and phenotypic investigation, allowing the achievement of viro-immunological success. The use of recently approved drugs with novel MoA, combined with an optimized background regimen, may also achieve virological suppression in people with LTO.

Increasing the bioavailability of oral esketamine by a single dose of cobicistat: A case study.

BACKGROUND: Intranasal esketamine is an approved drug for treatment­resistant depression (TRD); however, it is costly and may result in specific adverse effects. In this single case study, we explored if oral esketamine can be a suitable alternative. METHODS: In collaboration with a 39­year­old female with TRD, we compared plasma concentration curves of intranasal (84 mg) and oral (1, 2 and 4 mg/kg) esketamine. Because oral esketamine has a relatively low bioavailability, it results in a different ratio between esketamine and its primary metabolite noresketamine. To increase the bioavailability of oral esketamine, we co­administered a single dose of the cytochrome P­450 (CYP) 3A4 inhibitor cobicistat (150 mg). RESULTS: For all doses administered, oral esketamine resulted in lower esketamine but higher noresketamine peak plasma concentrations compared with intranasal treatment. Using oral esketamine it was not possible to generate a similar esketamine plasma concentration curve as with the intranasal treatment, except when combined with cobicistat (esketamine 2 mg/kg plus cobicistat 150 mg). CONCLUSIONS: Our findings demonstrate that cobicistat effectively increases the bioavailability of oral esketamine. Further research is required in a larger population, especially to investigate the clinical benefit of cobicistat as a booster drug for oral esketamine.

Outcome of Darunavir-Cobicistat-Based Regimens in HIV-Infected People Who Have Experienced Virological Failure.

Objective: To evaluate the virological outcome of darunavir-cobicistat (DRVc)-based regimens in adults living with HIV who had experienced virological failure (VF) on any previous drug combination. Methods: This was a retrospective cohort study (CSLHIV Cohort) of adults living with HIV who started a DRVc-based regimen with HIV-RNA >50 copies/mL after VF on any previous drug combination. Data on demographics, antiretroviral treatment since HIV diagnosis, and immunological and metabolic parameters from baseline (start of DRVc) to 48 weeks were analyzed in order to assess the cumulative proportion of those who achieved virological success (VS), defined as at least one instance of HIV-RNA <50 copies/mL within 12 months from baseline. Follow-up lasted from the start of the DRVc-based regimen (baseline) to the first instance of HIV-RNA <50 copies/mL, last available visit, or loss to follow-up or death, whichever occurred first. Univariate and multivariate Cox proportional-hazard regression models were used to identify baseline factors associated with VS. Results: A total of 176 individuals were included, and 120 (68.2%) achieved <50 HIV-RNA copies/mL within 12 months since baseline. On multivariate analysis, baseline HDL cholesterol was independently associated with the occurrence of VS (adjusted HR 1.021, 95% CI 1.004-1.038; p=0.014). Among the 120 subjects with VS, 27 (22.5%) had had VF during a median follow-up of 20.8 months since the first undetectable HIV-RNA. Resistance testing after VF was available in two cases, which harboured the HIV variant-bearing protease inhibitor-resistance mutations D30N, I50V, and N88D. During a median follow-up of 38.4 months, 65 of 176 (36.9%) individuals discontinued DRVc for any reason (37 of 120, 30.8%) and achieved VS vs. 28 of 56 (50%) without VS (p=0.019). Time to discontinuation was longer in people with VS (41.5 vs. 23.0 months, p=0.0007). No statistically significant changes were observed in immunological or lipid profiles during follow-up. Conclusion: Most individuals in this study achieved VS within 12 months from the beginning of a DRVc-based regimen; therefore, this treatment represent a viable option for people who have experienced VF on other regimens.

Synthetic and Clinical Perspectives of Evotaz: An Overview.

Viruses cause a variety of diseases in the human body. Antiviral agents are used to prevent the production of disease-causing viruses. These agents obstruct and kill the virus's translation and replication. Because viruses share the metabolic processes of the majority of host cells, finding targeted medicines for the virus is difficult. In the ongoing search for better antiviral agents, the USFDA approved EVOTAZ, a new drug discovered for the treatment of Human Immunodeficiency Virus (HIV). It is a once-daily (OD) fixed-dose combination of Cobicistat, a cytochrome P450 (CYP) enzyme inhibitor, and Atazanavir, a protease inhibitor. The combination drug was created in such a way that it can inhibit both CYP enzymes and proteases at the same time, resulting in the virus's death. The drug is not effective in children under the age of 18; however, it is still being studied for various parameters. This review article focuses on EVOTAZ's preclinical and clinical aspects, as well as its efficacy and safety profiles.

Broad-spectrum antiviral activity of two structurally analogous CYP3A inhibitors against pathogenic human coronaviruses in vitro.

Coronaviruses pose a permanent risk of outbreaks, with three highly pathogenic species and strains (SARS-CoV, MERS-CoV, SARS-CoV-2) having emerged in the last twenty years. Limited antiviral therapies are currently available and their efficacy in randomized clinical trials enrolling SARS-CoV-2 patients has not been consistent, highlighting the need for more potent treatments. We previously showed that cobicistat, a clinically approved inhibitor of Cytochrome P450-3A (CYP3A), has direct antiviral activity against early circulating SARS-CoV-2 strains in vitro and in Syrian hamsters. Cobicistat is a derivative of ritonavir, which is co-administered as pharmacoenhancer with the SARS-CoV-2 protease inhibitor nirmatrelvir, to inhibit its metabolization by CPY3A and preserve its antiviral efficacy. Here, we used automated image analysis for a screening and parallel comparison of the anti-coronavirus effects of cobicistat and ritonavir. Our data show that both drugs display antiviral activity at low micromolar concentrations against multiple SARS-CoV-2 variants in vitro, including epidemiologically relevant Omicron subvariants. Despite their close structural similarity, we found that cobicistat is more potent than ritonavir, as shown by significantly lower EC50 values in monotherapy and higher levels of viral suppression when used in combination with nirmatrelvir. Finally, we show that the antiviral activity of both cobicistat and ritonavir is maintained against other human coronaviruses, including HCoV-229E and the highly pathogenic MERS-CoV. Overall, our results demonstrate that cobicistat has more potent anti-coronavirus activity than ritonavir and suggest that dose adjustments could pave the way to the use of both drugs as broad-spectrum antivirals against highly pathogenic human coronaviruses.

Pharmacokinetics, Safety, and Tolerability of Once-Daily Darunavir With Cobicistat and Weekly Isoniazid/Rifapentine.

BACKGROUND: Once-weekly isoniazid with rifapentine (HP) for 3 months is a recommended treatment for latent tuberculosis infection in persons with HIV. HP reduces exposures of certain antiretroviral medications, resulting in limited options for the concomitant use of these therapies. Here, we examined the pharmacokinetics (PK), safety, and tolerability of darunavir/cobicistat with HP. METHODS: This was an open-label, fixed sequence, two-period crossover study in persons without HIV. Participants received darunavir 800 mg/cobicistat 150 mg once-daily alone for 4 days, then continued darunavir/cobicistat once-daily for days 5-19 with HP coadministration on days 5, 12, and 19. Intensive PK assessments were performed on days 4, 14, and 19. PK parameters were determined using noncompartmental methods. Geometric mean ratios with 90% confidence intervals (CIs) were calculated and compared between phases using mixed-effects models. RESULTS: Thirteen participants were enrolled. Two withdrew after day 4, and one withdrew after day 14. Of the 3 withdrawals, 2 were attributed to drug-related adverse events. Darunavir area under the concentration-time curve, maximum concentrations (Cmax), and concentrations at 24 hours postdose (C24h) were reduced by 71%, 41%, and 96% ∼48-72 hours after HP administration (day 14), respectively, and 36%, 17%, and 89% with simultaneous HP administration (day 19), respectively. On day 14, 45% of the predose and 73% of C24h concentrations were below the darunavir EC50 (0.055 µg/mL). CONCLUSIONS: Darunavir exposures were significantly decreased with HP coadministration. Temporal relationships between HP coadministration and the extent of induction or mixed inhibition/induction of darunavir metabolism were apparent. Coadministration of darunavir/cobicistat with 3HP should be avoided.

Protocol of the IntenSify-Trial: An open-label phase I trial of the CYP3A inhibitor cobicistat and the cytostatics gemcitabine and nab-paclitaxel in patients with advanced stage or metastatic pancreatic ductal adenocarcinoma to evaluate the combination's pharmacokinetics, safety, and efficacy.

Expression of CYP3A5 protein is a basal and acquired resistance mechanism of pancreatic ductal adenocarcinoma cells conferring protection against the CYP3A and CYP2C8 substrate paclitaxel through metabolic degradation. Inhibition of CYP3A isozymes restores the cells sensitivity to paclitaxel. The combination of gemcitabine and nab-paclitaxel is an established regimen for the treatment of metastasized or locally advanced inoperable pancreatic cancer. Cobicistat is a CYP3A inhibitor developed for the pharmacoenhancement of protease inhibitors. The addition of cobicistat to gemcitabine and nab-paclitaxel may increase the antitumor effect. We will conduct a phase I dose escalation trial with a classical 3 + 3 design to investigate the safety, tolerability, and pharmacokinetics (PKs) of gemcitabine, nab-paclitaxel, and cobicistat. Although the doses of gemcitabine (1000 mg/m2 ) and cobicistat (150 mg) are fixed, three dose levels of nab-paclitaxel (75, 100, and 125 mg/m2 ) will be explored to account for a potential PK drug interaction. After the dose escalation phase, we will set the recommended dose for expansion (RDE) and treat up to nine patients in an expansion part of the trial. The trial is registered under the following identifiers EudraCT-Nr. 2019-001439-29, drks.de: DRKS00029409, and ct.gov: NCT05494866. Overcoming resistance to paclitaxel by CYP3A5 inhibition may lead to an increased efficacy of the gemcitabine and nab-paclitaxel regimen. Safety, efficacy, PK, and RDE data need to be acquired before investigating this combination in a large-scale clinical study.

Severe lactic acidosis during tenofovir disoproxil fumarate and cobicistat combination for HIV patient.

Lactic acidosis is a rare but serious side effect in individuals receiving nucleoside reverse transcriptase inhibitors. An underweight woman with HIV was admitted to our hospital because of nausea and diffuse myalgia. Her antiretroviral regimen had been changed to tenofovir disoproxil fumarate (TDF)/emtricitabine and darunavir/cobicistat 3 months prior, after which her renal function had gradually declined. After admission, she was diagnosed with lactic acidosis, and a liver biopsy suggested mitochondrial damage. Her plasma tenofovir levels were elevated at the onset of lactic acidosis. We hypothesise that the patient's low body weight, combined with the addition of cobicistat, induced renal dysfunction and led to elevated plasma tenofovir concentrations, resulting in mitochondrial damage and lactic acidosis. Careful monitoring of renal function and lactic acidosis is required during use of TDF-containing regimens for underweight HIV patients, particularly when combined with cobicistat.

A four-drug combination oral tablet of darunavir, cobicistat, emtricitabine, and tenofovir alafenamide for the treatment of HIV-1 infection in adults.

INTRODUCTION: Darunavir (DRV)/cobicistat (COBI)/emtricitabine (FTC)/tenofovir alafenamide (TAF) is the only protease inhibitor-based single-tablet regimen (STR) approved for the treatment of HIV infection of adults and pediatric patients weighing at least 40 kg. DRV/COBI/FTC/TAF has demonstrated to be an effective regimen, to have a high genetic barrier to resistance, and to be well tolerated. AREAS COVERED: The authors summarize the chemistry and pharmacology of DRV, COBI, FTC, and TAF and discuss trials conducted on antiretroviral therapy (ART)-naïve and -experienced people living with HIV designed to evaluate safety, tolerability, and efficacy of the STR. This work also reports studies comparing DRV/COBI/FTC/TAF with competitive agents in real-world settings. EXPERT OPINION: Despite the availability of newer antiretroviral drugs and strategies in the management of HIV infection, including long-acting therapies, DRV/COBI/FTC/TAF is still considered an alternative regimen for the treatment of ART-naïve adults. DRV/COBI/FTC/TAF is an effective, well-tolerated, and safe antiretroviral regimen and represents a valid option for people who need to switch therapy due to tolerability issues, such as the onset of neuropsychiatric effects related to integrase strand transfer inhibitors, or virological failure.

Pharmacokinetic boosting of olaparib: A randomised, cross-over study (PROACTIVE-study).

BACKGROUND: Pharmacokinetic (PK) boosting is the intentional use of a drug-drug interaction to enhance systemic drug exposure. PK boosting of olaparib, a CYP3A-substrate, has the potential to reduce PK variability and financial burden. The aim of this study was to investigate equivalence of a boosted, reduced dose of olaparib compared to the non-boosted standard dose. METHODS: This cross-over, multicentre trial compared olaparib 300 mg twice daily (BID) with olaparib 100 mg BID boosted with the strong CYP3A-inhibitor cobicistat 150 mg BID. Patients were randomised to the standard therapy followed by the boosted therapy, or vice versa. After seven days of each therapy, dense PK sampling was performed for noncompartmental PK analysis. Equivalence was defined as a 90% Confidence Interval (CI) of the geometric mean ratio (GMR) of the boosted versus standard therapy area under the plasma concentration-time curve (AUC0-12 h) within no-effect boundaries. These boundaries were set at 0.57-1.25, based on previous pharmacokinetic studies with olaparib capsules and tablets. RESULTS: Of 15 included patients, 12 were eligible for PK analysis. The GMR of the AUC0-12 h was 1.45 (90% CI 1.27-1.65). No grade ≥3 adverse events were reported during the study. CONCLUSIONS: Boosting a 100 mg BID olaparib dose with cobicistat increases olaparib exposure 1.45-fold, compared to the standard dose of 300 mg BID. Equivalence of the boosted olaparib was thus not established. Boosting remains a promising strategy to reduce the olaparib dose as cobicistat increases olaparib exposure Adequate tolerability of the boosted therapy with higher exposure should be established.

Lipid profile changes associated with antiretroviral therapies in a real-world cohort. / [Artículo traducido] Cambios en el perfil lipídico asociados con las terapias antirretrovirales en una cohorte de vida real.

OBJECTIVE: To compare lipid profile changes and cardiovascular events among HIV naïve and experienced patients from a real-world cohort treated with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide fumarate or dolutegravir/abacavir/lamivudine. METHOD: A retrospective cohort study in HIV naïve and experienced people at a reference hospital in Spain was done. During the follow-up (March 2015-June 2019), patients were treated with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide fumarate or dolutegravir/abacavir/lamivudine. Epidemiological, clinical and immunovirological variables were recorded. A statistical analysis of the lipid profile at baseline, 48 and 120 weeks after initiating the study therapy, cardiovascular events (myocardial infarction, heart failure, cerebrovascular accident, deep venous thrombosis, myocardiopathy, non-ST- segment elevation acute coronary syndrome, and ST-segment elevation myocardial infarction) and cardiovascular risks factors was performed. Data were analysed in naïve and experienced patients from each of the study treatments. The data was obtained from the medical history. The statistical analysis was performed with SPSS v.24 software. RESULTS: A total of 266 and 191 patients receiving treatment with elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide fumarate and dolutegravir/abacavir/lamivudine were included in the study, respectively. After 120 weeks of treatment, a worsening of the lipid profile was found in the elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide fumarate group, both in naïve and experienced patients, whereas not so conspicuously observed in the dolutegravir/abacavir/lamivudine group. Statistically significant differences between both groups were found in experienced patients favoring dolutegravir/abacavir/lamivudine; in total cholesterol (204.1 ± 38.2 vs. 187.3 ± 29.4, p < 0.001) and LDL-C (126.1 ± 31.9 vs. 113.5 ± 28.5, p = 0.001) at week 48, and in total cholesterol (201.1 ± 33.4 vs. 188.7 ± 33.9, p = 0.013) and HDL-C (54.2 ± 15.6 vs. 48.3 ± 14.3, p = 0.01) at week 120. No significant differences in cardiovascular events were found, neither in naïve nor in experienced patients. CONCLUSIONS: The lipid profile among elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide fumarate group worsened throughout the follow-up, both in naïve and experienced patients, not so remarkable in the dolutegravir/abacavir/lamivudine group. Both regimens were well tolerated, with similar rates of cardiovascular events.

Prophylaxis by doravirine-lamivudine-tenofovir disoproxil fumarate or elvitegravir-cobicistat-emtricitabine-tenofovir alafenamide after sexual exposure to HIV.

HIV post- exposure prophylaxis (PEP) is a prevention tool for individuals with a recent potential exposure to HIV. Doravirine has been available since 2019 in combination with tenofovir disoproxil fumarate and lamivudine and has not been evaluated as a PEP. DOR/3TC/TDF is our department's most commonly prescribed PEP treatment since 2021. This study evaluates the completion rate of the DOR/3TC/TDF as compared to EVG/c/FTC/TAF for PEP, which was the regimen prescribed until 2020 in our hospital.This retrospective observational study was conducted between January 2020 and September 2021. The subjects included consecutively were adults who consulted for an HIV sexual exposure accident and for whom DOR/3TC/TDF in 2021 or EVG/c/FTC/TAF in 2020 was prescribed. The outcomes were the completion rate to the end of treatment (28 days), the seroconversion rate, and the description of side effects.During the study period, 311 people were included: 140 treated with DOR/3TC/TDF and 171 treated with EVGc/FTC/TAF. Considering subjects with a follow-up visit, the completion rate was 96.8% (90/93) in the DOR/3TC/TDF group, and 94.6% (123/130) in the EVG/c/FTC/TAF group (p-value: 0.53). The number of people lost to follow-up was nearly equivalent in both groups: 27.1% (38/140) in the DOR/3TC/TDF group and 23.4% (40/171) in the EVG/c/FTC/TAF group (p-value: 0.45). A side effect was described for 38% (36/94) in the DOR/3TC/TDF group, and 29.7% (38/128) in the EVG/c/FTC/TAF group. No cases of seroconversion were observed.DOR/3TC/TDF appears to have a similar safety profile to EVG/c/FTC/TAF. Due to its lower cost, it seems to be a treatment option for consideration in the context of HIV-exposure accidents.

Switching to bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) plus darunavir/cobicistat in heavily antiretroviral-experienced, virologically suppressed HIV-infected adults receiving complex regimens.

OBJECTIVES: To evaluate the efficacy and safety of the two-pill regimen bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) plus darunavir/cobicistat as a switching strategy in heavily treatment-experienced people living with HIV (PLWH). METHODS: Multicentre, prospective, single-arm pilot clinical trial. Participants were virologically suppressed adults receiving a stable antiretroviral regimen of at least three pills from at least three drug families due to previous virological failures and/or toxicities with no documented resistance to integrase strand transfer inhibitors or darunavir (≥15 points, Stanford). Clinical and laboratory assessments were performed at 0, 4, 12, 24, 36 and 48 weeks. HIV-1 proviral DNA was amplified and sequenced by Illumina at baseline. Plasma bictegravir concentrations were determined in 22 patients using UHPLC-MS/MS. The primary study endpoint was viral load (VL)< 50 copies/mL at Week 48 (ITT). RESULTS: We enrolled 63 participants (92% men) with median baseline CD4 count of 515 cells/mm3 (IQR: 334.5-734.5), 24 years on ART (IQR: 15.9-27.8). The median number of pills was 4 (range: 3-10). At baseline, proviral DNA was amplified in 39 participants: 33/39 had resistance mutations. Three participants discontinued owing to toxicity. At 48 weeks, 95% had VL < 50 copies/mL by ITT and 100% by PP analysis. A modest increase was observed in the bictegravir plasma concentration, and a significant decrease in estimated glomerular filtration rate was observed only at Week 4, probably related to interaction with renal transporters. CONCLUSIONS: Our data suggest that BIC/FTC/TAF + darunavir/cobicistat is an effective, well-tolerated regimen that may improve convenience and, potentially, long-term success in stable heavily pre-treated PLWH.

HIV-DNA decrease during treatment in primary HIV-1 infection with three different drug regimens: Italian Network of Acute HIV Infection (INACTION) clinical trial.

As the introduction of antiretroviral therapy (ART) during primary HIV-1 infection (PHI) could restrict the establishment of HIV reservoirs, we aimed to assess the effect of three different ART regimens on HIV-DNA load in people living with HIV (PLWH), who started ART in PHI. Randomized, open-label, multicentric study, including subjects in PHI (defined as an incomplete HIV-1 Western blot and detectable plasma HIV-RNA) in the Italian Network of Acute HIV Infection cohort. Participants were randomly assigned (10:10:8) to a fixed-dose combination of tenofovir alafenamide fumarate (TAF) 10 mg plus emtricitabine (FTC) 200 mg, darunavir 800 mg, and cobicistat 150 mg once daily (group A), or TAF 25 mg plus FTC 200 mg, dolutegravir 50 mg once daily (group B), or an intensified four-drug regimen (TAF 10 mg plus FTC 200 mg, dolutegravir 50 mg, darunavir 800 mg, and cobicistat 150 mg once daily) (group C). The primary endpoint was the decrease of HIV-DNA copies/106 peripheral blood mononuclear cells (PBMCs) at weeks (W) 12 and 48. Secondary endpoints were increased in CD4+ cells and in CD4+/CD8+ ratio and percentage of PLWH reaching undetectable HIV-RNA. HIV-DNA was quantified by Droplet Digital PCR (Biorad QX100) and normalized to RPP30 reference gene. This study was registered in ClinicalTrials.gov (number NCT04225325). Among 78 participants enrolled, 30 were randomized to group 1, 28 to group 2, and 20 to group 3. At baseline, median CD4+ count was 658/µL (476-790), HIV-RNA 5.37 (4.38, 6.12) log10 copies/mL, without statistical difference in their change among groups at weeks 12 and 48 (p = 0.432 and 0.234, respectively). The trial was prematurely discontinued for slow accrual and for COVID-19 pandemic-associated restrictions. In the per-protocol analysis, PLWH (n = 72) with undetectable viral load was 54.3% at W12 and 86.4% at W48. Interestingly, the CD4/CD8 ratio progressively increased over time, up to normalization in almost half of the cohort by week 48, despite a deflection in group 3; no difference was observed by the Fiebig stage (I-III vs. IV-VI). HIV-DNA decreased from 4.46 (4.08, 4.81) log10 copies/106 PBMCs to 4.22 (3.79, 4.49) at week 12, and 3.87 (3.46, 4.34) at week 48, without difference among groups. At multivariable analysis, HIV-DNA delta at W48 was associated only with the increase of CD4+ count by 100 cells/mm3 but not with the Fiebig stage, the CD4+/CD8+ ratio, and treatment arm, despite a higher decrease in group 3. Six adverse events were recorded during our study, which did not cause any withdrawal from the study. We observed a decrease in HIV-DNA from baseline to W48 in PLWH treated during PHI, associated with an increase in CD4+ count, unrelated to the treatment arm.

Effectiveness and safety of integrase strand transfer inhibitors in Spain: a prospective real-world study.

Introduction: Second-generation integrase strand transfer inhibitors (INSTIs) are preferred treatment options worldwide, and dolutegravir (DTG) is the treatment of choice in resource-limited settings. Nevertheless, in some resource-limited settings, these drugs are not always available. An analysis of the experience with the use of INSTIs in unselected adults living with HIV may be of help to make therapeutic decisions when second-generation INSTIs are not available. This study aimed to evaluate the real-life effectiveness and safety of dolutegravir (DTG), elvitegravir/cobicistat (EVG/c), and raltegravir (RAL) in a large Spanish cohort of HIV-1-infected patients. Methods: Real-world study of adults living with HIV who initiated integrase INSTIs DTG, EVG/c, and RAL-based regimens in three settings (ART-naïve patients, ART-switching, and ART-salvage patients). The primary endpoint was the median time to treatment discontinuation after INSTI-based regimen initiation. Proportion of patients experiencing virological failure (VF) (defined as two consecutive viral loads (VL) ≥200 copies/mL at 24 weeks or as a single determination of VL ≥1,000 copies/mL while receiving DTG, EVG/c or RAL, and at least 3 months after INSTI initiation) and time to VF were also evaluated. Results: Virological effectiveness of EVG/c- and RAL-based regimens was similar to that of DTG when given as first-line and salvage therapy. Treatment switching for reasons other than virological failure was more frequent in subjects receiving EVG/c and, in particular, RAL. Naïve patients with CD4+ nadir <100 cells/µL were more likely to develop VF, particularly if they initiated RAL or EVG/c. In the ART switching population, initiation of RAL and EVG/c was associated with both VF and INSTI discontinuation. There were no differences in the time to VF and INSTI discontinuation between DTG, EVG/c and RAL. Immunological parameters improved in the three groups and for the three drugs assessed. Safety and tolerability were consistent with expected safety profiles. Discussion: Whereas second-generation INSTIs are preferred treatment options worldwide, and DTG is one of the treatment of choices in resource-limited settings, first-generation INSTIs may still provide high virological and immunological effectiveness when DTG is not available.

Two-Drug Regimen Containing Darunavir: Metabolic Evaluation of an Old Dual Therapy.

Regimens containing darunavir are one of the first one with two drugs that demonstrated good efficacy as a simplification strategy. We wanted to describe the characteristics of patients followed in our center on a dual therapy regimen containing darunavir evaluating the metabolic aspects during follow-ups. We collected data from 208 patients switching to lamivudine plus darunavir with either ritonavir or cobicistat between 2010 and 2019. In all patients we found an increase in low-density lipoprotein (LDL), with no rising in creatinine, total cholesterol, or triglycerides. Twenty-five patients reached 120 weeks of follow-up. In these patients, no significant metabolic changes were described without concomitant treatment with drugs for dyslipidemia. These regimens seem to be more tolerable in metabolic profile compared with the data concerning three-drug therapies, leading only to a slight increase in LDL. The main reason for discontinuation was for a single-tablet therapy. None of the patients started treatment for dyslipidemia.

Utilization of Chemometric-Aided UV Spectrophotometric Methods for Concurrent Assessment of Emtricitabine, Tenofovir Disoproxil Fumarate, Elvitegravir, and Cobicistat in Tablet Formulation.

BACKGROUND: Emtricitabine (ETC), tenofovir disoproxil fumarate (TNF), elvitegravir (EVG), and cobicistat (CBS) are antiviral drugs used to treat human immunodeficiency virus (HIV) infections. OBJECTIVE: To develop chemometric-aided UV spectrophotometric methods for concurrent estimation of the aforementioned drugs used to treat HIV. This method can be used to reduce modification of the calibration model by assessing the absorbance at various points in the zero-order spectra within the selected wavelength range. Additionally, it eliminates interfering signals and provides sufficient resolution in multi-component systems. METHODS: Two chemometric-assisted UV spectrophotometric methods, namely, partial least-squares (PLS) and principal component regression (PCR) models, were established for the concurrent assessment of EVG, CBS, TNF, and ETC in tablet formulations. The proposed methods were applied to decrease complexity of overlapped spectra and to achieve maximum sensitivity and the lowest error. These approaches were performed in accordance with International Council on Harmonization (ICH) criteria and compared to the reported HPLC method. RESULTS: The proposed methods were used to assess EVG, CBS, TNF, and ETC in the ranges of 5-30, 5-30 , 5-50, and 5-50 µg/mL, respectively, with an excellent correlation coefficient (r2 ≥ 0.998). The accuracy and precision results were found to be within the acceptable limits. No statistical difference was observed between the proposed and reported studies. CONCLUSION: The chemometric-aided UV spectrophotometric approaches could be considered as alternatives to chromatographic procedures in the pharmaceutical industry for routine analysis and testing of readily accessible commercial formulations. HIGHLIGHTS: Novel chemometric-assisted UV spectrophotometric techniques were developed for assessment of multicomponent antiviral combinations in single-tablet formulations. The proposed methods were performed without using harmful solvents, tedious preparation, or expensive instruments. The proposed methods were compared statistically with a reported HPLC method. Assessment of EVG, CBS, TNF, and ETC was performed without interference from excipients in their multicomponent formulations.