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Long‐acting technologies (LATs) for hepatitis C virus (HCV) are under development as a strategy to improve linkage to care, treatment adherence and outcomes. We conducted a survey of HCV treatment prescribers and HCV policymakers in low‐ and middle‐income countries (LMICs) regarding acceptability and feasibility of HCV LATs. We included one‐time intramuscular injection, subdermal implant and transdermal patch as potential LAT options. We surveyed participants regarding optimal health system and patient characteristics, concerns, potential barriers, overall feasibility and preferences for HCV LAT as compared to daily oral medication. Overall, 122 providers and 50 policymakers from 42 LMICs completed the survey. Among providers, 93% (113/122) expressed willingness to prescribe LAT and 72% (88/120) of providers preferred LAT if provided at comparable efficacy, safety and cost as current oral treatments. Of providers preferring HCV LAT to daily oral medication, 67% (59/88) preferred injection, 24% (21/88) preferred patch and 9% (8/88) preferred implant. Only 20% (24/122) would prescribe LAT if it were more costly than oral treatment. In regression analysis, no provider characteristics were associated with preference for LAT over oral treatment. Policymakers reported high likelihood that LAT would be included in treatment guidelines (42/50; 84%) and national drug formularies (39/50; 78%) if efficacy, safety and cost were similar to oral treatment. HCV LATs could advance progress to HCV elimination in LMICs by diversifying treatment options to improve treatment coverage and outcomes. Provider preferences from LMICs are a critical consideration in the development of HCV LATs to ensure its early and equitable availability in LMICs. [ABSTRACT FROM AUTHOR]

Model-informed drug repurposing: viral kinetic modelling to prioritize rational drug combinations for COVID-19. For example, some of these challenges were highlighted recently by the International Society for Aerosols in Medicine, as part of their call for consideration of inhaled delivery.[12] Several advanced drug delivery strategies can be applied much more rapidly than new drug development and do not need to be prohibitively expensive for global community programmes. Keywords: coronavirus; drug development; equitable access; repurposing; SARS-CoV-2 EN coronavirus drug development equitable access repurposing SARS-CoV-2 421 423 3 12/22/22 20230101 NES 230101 Given time, drug discovery programmes will undoubtedly yield highly potent drugs to form the basis of optimised COVID-19 regimens. [Extracted from the article]

Introduction: Portal hypertension (PH) is associated with complications including refractory ascites and variceal haemorrhage and can be treated endovascularly with a Transjugular Intrahepatic Portosystemic Shunt (TIPS). Portal vein puncture during TIPS using real‐time transabdominal ultrasound guidance is one of many portal vein puncture techniques and is seldom used compared with other methods. The purpose of this manuscript is to describe this technique and its associated procedural outcomes at a quaternary liver transplant hospital. Methods: Clinical data of all patients who underwent ultrasound‐guided TIPS at our institution between 1 January 2009 and 1 January 2019 were retrospectively obtained from electronic medical records and reviewed. Patient demographics, indications, procedural outcomes and complications were recorded. Results: Forty‐four ultrasound‐guided TIPS procedures were performed during the study period. The most common indication for TIPS was refractory ascites (n = 26; 57%) and variceal haemorrhage (n = 12; 26%). Technical success rate was 100%. No intraprocedural complications occurred. Periprocedural complication rate was 35% (n = 16) with encephalopathy (n = 8; 17%) and sepsis (n = 5; 11%) the most common. One patient with sepsis died. No other TIPS‐related deaths occurred. Median fluoroscopy time, contrast volume, air kerma and dose area product values for all procedures were 35 minutes (IQR 24–51), 100 ml (IQR 70–160), 0.95 Gy (IQR 0.50–1.53) and 127 Gycm2 (IQR 68.75–206), respectively. Conclusion: Transabdominal ultrasound‐guided portal vein puncture during TIPS is safe and technically feasible. When compared to fluoroscopically guided methods, it is associated with lower intraprocedural complication rates, fluoroscopy times, contrast volumes and radiation doses in our experience. Radiation doses, FTs and contrast volumes were also considerably lower than recommended limits. [ABSTRACT FROM AUTHOR]

Objectives: The World Health Organization recommends that all countries adopt dolutegravir‐based antiretroviral therapy as the preferred regimen for all individuals living with HIV. Levonorgestrel is a commonly used hormonal contraceptive, which undergoes drug–drug interactions with some antiretrovirals, but the potential interaction between dolutegravir and levonorgestrel has not been examined. We aimed to evaluate cytochrome P450 (CYP)‐mediated levonorgestrel metabolism and quantify the effects of dolutegravir on levonorgestrel apparent intrinsic clearance (CLint.app.) and CYP gene expression. Methods: In vitro CYP‐mediated CLint.app. of levonorgestrel was quantified using a recombinant human CYP (rhCYP) enzyme system. A primary human hepatocyte model of drug metabolism was used to assess the effects of dolutegravir on (1) levonorgestrel CLint.app., using liquid chromatography‐tandem mass spectrometry, and (2) the expression of specific CYP enzymes, using quantitative real‐time polymerase chain reaction. Results: Levonorgestrel clearance was mediated by multiple rhCYPs, including rhCYP3A4. Under control conditions, levonorgestrel CLint.app. was 22.4 ± 5.0 μL/min/106 hepatocytes. Incubation with 43.1 nM of unbound dolutegravir elevated levonorgestrel CLint.app. to 31.4 ± 7.8 µL/min/106 hepatocytes (P = 0.168), while 142.23 nM increased levonorgestrel CLint.app. to 37.0 ± 2.9 µL/min/106 hepatocytes (P = 0.012). Unbound dolutegravir ≥ 431 nM induced expression of CYP3A4 (≥ two‐fold) in a dose‐dependent manner, while 1.44 μM of unbound dolutegravir induced CYP2B6 expression 2.2 ± 0.3‐fold (P = 0.0004). Conclusions: In summary, this in vitro study suggests that dolutegravir has the potential to increase hepatic clearance of levonorgestrel by inducing both CYP3A and non‐CYP3A enzymes. The observed in vitro dolutegravir–levonorgestrel drug–drug interaction should be further examined in clinical studies. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic, caused by the SARS‐CoV‐2 coronavirus, has triggered a worldwide health emergency. Here, we show that ferritin‐like Dps from hyperthermophilic Sulfolobus islandicus, covalently coupled with SARS‐CoV‐2 antigens via the SpyCatcher system, forms stable multivalent dodecameric vaccine nanoparticles that remain intact even after lyophilisation. Immunisation experiments in mice demonstrated that the SARS‐CoV‐2 receptor binding domain (RBD) coupled to Dps (RBD‐S‐Dps) elicited a higher antibody titre and an enhanced neutralising antibody response compared to monomeric RBD. A single immunisation with RBD‐S‐Dps completely protected hACE2‐expressing mice from serious illness and led to viral clearance from the lungs upon SARS‐CoV‐2 infection. Our data highlight that multimerised SARS‐CoV‐2 subunit vaccines are a highly efficacious modality, particularly when combined with an ultra‐stable scaffold. [ABSTRACT FROM AUTHOR]

The urgent global public health need presented by severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) has brought scientists from diverse backgrounds together in an unprecedented international effort to rapidly identify interventions. There is a pressing need to apply clinical pharmacology principles and this has already been recognized by several other groups. However, one area that warrants additional specific consideration relates to plasma and tissue protein binding that broadly influences pharmacokinetics and pharmacodynamics. The principles of free drug theory have been forged and applied across drug development but are not currently being routinely applied for SARS‐CoV‐2 antiviral drugs. Consideration of protein binding is of critical importance to candidate selection but requires correct interpretation, in a drug‐specific manner, to avoid either underinterpretation or overinterpretation of its consequences. This paper represents a consensus from international researchers seeking to apply historical knowledge, which has underpinned highly successful antiviral drug development for other viruses, such as HIV and hepatitis C virus for decades. [ABSTRACT FROM AUTHOR]

Intense efforts are underway to evaluate potential therapeutic agents for the treatment of COVID-19. In order to respond quickly to the crisis, the repurposing of existing drugs is the primary pharmacological strategy. Despite the urgent clinical need for these therapies, it is imperative to consider potential safety issues. This is important due to the harm-benefit ratios that may be encountered when treating COVID-19, which can depend on the stage of the disease, when therapy is administered and underlying clinical factors in individual patients. Treatments are currently being trialled for a range of scenarios from prophylaxis (where benefit must greatly exceed risk) to severe life-threatening disease (where a degree of potential risk may be tolerated if it is exceeded by the potential benefit). In this perspective, we have reviewed some of the most widely researched repurposed agents in order to identify potential safety considerations using existing information in the context of COVID-19. [ABSTRACT FROM AUTHOR]

Aims: Lopinavir (LPV) is not a first‐line regimen. According to recent WHO data, LPV usage in low‐ and middle‐income countries accounted for approximately 52% of the adult and 23% of the paediatric protease inhibitor market in 2017. Since LPV is a substrate for the SLCO1B1 (OATP1B1) transporter, the aim of this study was to assess the impact of SLCO1B1 polymorphisms (rs11045819, rs4149032 and rs4149056) on LPV trough plasma concentrations (Ctrough) in Serbian patients. Methods: Plasma samples from 104 HIV/AIDS Caucasians were collected. LPV Ctrough was quantified using liquid‐chromatography‐mass spectrometry. Genotyping was carried out using real‐time‐PCR‐based allelic discrimination. One‐way analysis of variance, t test and linear regression were used for data analysis. Results: The overall mean (SD) LPV Ctrough was 5885 ± 2755 ng/mL. Significant differences were between patients with different rs11045819 genotypes: CC (LPV median Ctrough = 6072 ng/mL, interquartile range (IQR) = 4318–7617 ng/mL), CA (LPV median Ctrough = 4987 ng/mL, IQR = 4300–6295 ng/mL) and AA (LPV median Ctrough = 3648 ng/mL, IQR = 1949–4072 ng/mL) (P =.005). Significant differences were also observed according to rs4149032 genotype: CC (LPV median Ctrough = 6027 ng/mL, IQR =4548–8250 ng/mL), CT (LPV median Ctrough = 5553 ng/mL, IQR = 4300–6888 ng/mL) and TT (LPV median Ctrough = 4408 ng/mL, IQR = 3361–5233 ng/mL) (P =.007). For rs4149056 a statistically significant difference between T‐homozygotes (LPV median Ctrough = 5434 ng/mL, IQR = 3855–6830 ng/mL), heterozygotes (LPV median Ctrough = 6707 ng/mL, IQR = 5088–8063 ng/mL) and C‐homozygotes (LPV median Ctrough = 13906 ng/mL, IQR = 12946–14866 ng/mL) was observed (P =.002). In multivariate regression analysis, only the SLCO1B1 rs4149056 polymorphism was independently associated with higher LPV Ctrough (β = 2834.5 [1442–4226.9] ng/mL [P =.001]). Conclusions: Our results demonstrate a statistically significant influence of the SLCO1B1 rs4149056 polymorphism on higher LPV Ctrough in Caucasian HIV/AIDS patients. [ABSTRACT FROM AUTHOR]

Cytochrome P450 2B6 (CYP2B6) is involved in the metabolism of the antimalarial drugs artemether and lumefantrine. Here we investigated the effect of CYP2B6*6 on the plasma pharmacokinetics of artemether, lumefantrine, and their metabolites in healthy volunteers. Thirty healthy and previously genotyped adult volunteers—15 noncarriers (CYP2B6*1/*1) and 15 homozygote carriers (CYP2B6*6/*6)—selected from a cohort of 150 subjects from the Ilorin metropolitan area were administered the complete 3‐day course of artemether and lumefantrine (80 and 480 mg twice daily, respectively). Intensive pharmacokinetic sampling was conducted at different time points before and after the last dose. Plasma concentrations of artemether, lumefantrine, dihydroartemisinin, and desbutyllumefantrine were quantified using validated liquid chromatography–mass spectrometric methods. Pharmacokinetic parameters were evaluated using noncompartmental analysis. Artemether clearance of CYP2B6*6/*6 volunteers was nonsignificantly lower by 26% (ratios of geometric mean [90% CI]; 0.74 [0.52‐1.05]), and total exposure (the area under the plasma concentration‐time curve from time 0 to infinity [AUC0‐∞]) was greater by 35% (1.35 [0.95‐1.93]) when compared with those of *1/*1 volunteers. Similarly, assuming complete bioconversion from artemether, the dihydroartemisinin AUC0‐∞ was 22% lower. On the contrary, artemether‐to‐dihydroartemisinin AUC0‐∞ ratio was 73% significantly higher (1.73 [1.27‐2.37]). Comparison of lumefantrine exposure and lumefantrine‐to‐desbutyllumefantrine metabolic ratio of *6/*6 with corresponding data from *1/*1 volunteers showed no differences. The increased artemether‐to‐dihydroartemisinin metabolic ratio of *6/*6 volunteers is unlikely to result in differences in artemether‐lumefantrine efficacy and treatment outcomes. This is the first study in humans to associate CYP2B6*6 genotype with artemether disposition. [ABSTRACT FROM AUTHOR]

Vertebral compression fractures (VCFs) are a common cause of back pain and disability and are usually osteoporotic in nature. Therapy aims to adequately control pain and allow early mobilisation and return of function while preventing additional fractures. A proportion of patients do not achieve adequate pain relief using conservative measures alone. Unwanted adverse effects from medications may also ensue. Vertebroplasty represents an alternative treatment option for VCFs. Patients with acute VCFs (≤6 weeks old) may gain the most benefit from vertebroplasty as healed fractures are not as amenable to cement injection. High-quality studies have reported conflicting results regarding the use of vertebroplasty in the treatment of acute VCFs. Despite high-quality evidence, varying study designs and heterogenous patient cohorts make interpretation of this data difficult. Only one sham-controlled randomised controlled trial (RCT) has evaluated vertebroplasty exclusively in patients with acute VCFs, reporting favourable results. Pooled data from RCTs also suggest vertebroplasty to be safe. This article provides a concise and critical review of the current literature regarding vertebroplasty for the treatment of acute VCFs. [ABSTRACT FROM AUTHOR]

Aims: In this study the influence of first‐line antimalarial drug artemether‐lumefantrine on the pharmacokinetics of the antiretroviral drug nevirapine was investigated in the context of selected single nucleotide polymorphisms (SNPs) in a cohort of adult HIV‐infected Nigerian patients. Methods: This was a two‐period, single sequence crossover study. In stage 1, 150 HIV‐infected patients receiving nevirapine‐based antiretroviral regimens were enrolled and genotyped for seven SNPs. Sparse pharmacokinetic sampling was conducted to identify SNPs independently associated with nevirapine plasma concentration. Patients were categorized as poor, intermediate and extensive metabolizers based on the numbers of alleles of significantly associated SNPs. Intensive sampling was conducted in selected patients from each group. In stage 2, patients received standard artemether‐lumefantrine treatment with nevirapine, and intensive pharmacokinetic sampling was conducted on day 3. Results: No clinically significant changes were observed in key nevirapine pharmacokinetic parameters, the 90% confidence interval for the measured changes falling completely within the 0.80–1.25 no‐effect boundaries. However, the number of patients with trough plasma nevirapine concentration below the 3400 ng ml−1 minimum effective concentration increased from 10% without artemether‐lumefantrine (all extensive metabolizers) to 21% with artemether‐lumefantrine (14% extensive, 4% intermediate, and 3% poor metabolizers). Conclusions: This approach highlights additional increase in the already existing risk of suboptimal trough plasma concentration, especially in extensive metabolizers when nevirapine is co‐administered with artemether‐lumefantrine. [ABSTRACT FROM AUTHOR]

Protein synthesis inhibitors are commonly used for measuring protein degradation rates, but may cause cytotoxicity via direct or indirect mechanisms. This study aimed to identify concentrations providing optimal inhibition in the absence of overt cytotoxicity. Actinomycin D, cycloheximide, emetine, and puromycin were assessed individually, and in two-, three-, and four-drug combinations for protein synthesis inhibition ( IC50) and cytotoxicity ( CC50) over 72 h. Experiments were conducted in HepG2 cells and primary rat hepatocytes ( PRH). IC50 for actinomycin D, cycloheximide, emetine, and puromycin were 39 ± 7.4, 6600 ± 2500, 2200 ± 1400, and 1600 ± 1200 nmol/L; with corresponding CC50 values of 6.2 ± 7.3, 570 ± 510, 81 ± 9, and 1300 ± 64 nmol/L, respectively, in HepG2 cells. The IC50 were 1.7 ± 1.8, 290 ± 90, 620 ± 920, and 2000 ± 2000 nmol/L, with corresponding CC50 values of 0.98 ± 1.8, 680 ± 1300, 180 ± 700, and 1600 ± 1000 ( SD) nmol/L, respectively, in PRH. CC50 were also lower than the IC50 for all drug combinations in HepG2 cells. These data indicate that using pharmacological interference is inappropriate for measuring protein degradation over a protracted period, because inhibitory effects cannot be extricated from cytotoxicity. [ABSTRACT FROM AUTHOR]

Tuberculosis kills more people worldwide than any other infectious disease. Treatment requires multiple drug therapy administered over long periods (6-24 months). The emergence of multidrug-resistant strains is a major problem, and with few new drugs in the pipeline, a novel modus operandi is urgently required. Solid drug nanoparticles (SDNs), a new development in nanomedicine, offer a fresh therapeutic approach. Here, we show that SDNs are more effective (50-fold) at killing pathogenic mycobacteria than aqueous forms of the same drug and can target mycobacteria internalised by macrophages, where bacilli reside. We demonstrate synthesis of dual and triple drug loaded SDNs, facilitating combination tuberculosis therapy. Our results suggest that by employing SDNs of existing antibiotics, it may be possible to improve drug delivery and therefore reduce drug dosage to lessen side effects and fight drug resistance. [ABSTRACT FROM AUTHOR]

The antiretroviral drug efavirenz displays many desirable pharmacokinetic properties such as a long half-life enabling once daily dosing but suffers from central nervous system safety issues. Various nanotechnologies have been explored to mitigate some of the limitations with efavirenz. While there has been progress in increasing the bioavailability, there has been no attempt to assess the impact of increased exposure to efavirenz on central nervous system safety. The uptake of aqueous and solid drug nanoparticle (SDN) formulations of efavirenz was assessed in the human cerebral microvessel endothelial cells/D3 brain endothelial cell line. The mechanisms of uptake were probed using a panel of transport and endocytosis inhibitors. The cellular accumulation of an efavirenz aqueous solution was significantly reduced by amantadine, but this was not observed with SDNs. The uptake of efavirenz SDNs was reduced by dynasore, but concentrations of the efavirenz aqueous solution were not affected. These data indicate that efavirenz is a substrate for transporters in brain endothelial cells (amantadine is an inhibitor of organic cation transporters 1 and 2), and formation of SDNs may bypass this interaction in favour of a mechanism involving dynamin-mediated endocytosis. [ABSTRACT FROM AUTHOR]

Solid drug nanoparticles (SDNs) are a nanotechnology with favourable characteristics to enhance drug delivery and improve the treatment of several diseases, showing benefit for improved oral bioavailability and injectable long-acting medicines. The physicochemical properties and composition of nanoformulations can influence the absorption, distribution, and elimination of nanoparticles; consequently, the development of nanoparticles for drug delivery should consider the potential role of nanoparticle characteristics in the definition of pharmacokinetics. The aim of this study was to investigate the pharmacological behaviour of efavirenz SDNs and the identification of optimal nanoparticle properties and composition. Seventy-seven efavirenz SDNs were included in the analysis. Cellular accumulation was evaluated in HepG2 (hepatic) and Caco-2 (intestinal), CEM (lymphocyte), THP1 (monocyte), and A-THP1 (macrophage) cell lines. Apparent intestinal permeability (Papp) was measured using a monolayer of Caco-2 cells. The Papp values were used to evaluate the potential benefit on pharmacokinetics using a physiologically based pharmacokinetic model. The generated SDNs had an enhanced intestinal permeability and accumulation in different cell lines compared to the traditional formulation of efavirenz. Nanoparticle size and excipient choice influenced efavirenz apparent permeability and cellular accumulation, and this appeared to be cell line dependent. These findings represent a valuable platform for the design of SDNs, giving an empirical background for the selection of optimal nanoparticle characteristics and composition. Understanding how nanoparticle components and physicochemical properties influence pharmacological patterns will enable the rational design of SDNs with desirable pharmacokinetics. [ABSTRACT FROM AUTHOR]

Aims Using a model-based approach, the efavirenz steady-state pharmacokinetics in African children is characterized, quantifying demographic and genotypic effects on the drug's disposition. Simulations are also conducted allowing prediction of optimized doses of efavirenz in this population. Methods We modelled the steady-state population pharmacokinetics of efavirenz in Ugandan and Zambian children using nonlinear mixed-effects modelling. Individual mid-dose efavirenz concentrations were derived and simulations explored genotype-based dose optimization strategies. Results A two-compartment model with absorption through transit compartments well described 2086 concentration-time points in 169 children. The combined effect of single nucleotide polymorphisms (SNPs) 516G>T and 983T>C explained 44.5% and 14.7% of the variability in efavirenz clearance and bioavailability, respectively. The detected frequencies of composite CYP2B6 genotype were 0.33 for 516GG|983TT, 0.35 for 516GT|983TT, 0.06 for 516GG|983TC, 0.18 for 516TT|983TT, 0.07 516GT|983TC and 0.01 for 516GG|983CC. The corresponding estimated clearance rates were 6.94, 4.90, 3.93, 1.92, 1.36, and 0.74 l h−1 for a 15.4 kg child and median (95% CI) observed mid-dose concentrations 1.55 (0.51-2.94), 2.20 (0.97-4.40), 2.03 (1.19-4.53), 7.55 (2.40-14.74), 7.79 (3.66-24.59) and 18.22 (11.84-22.76) mg l−1, respectively. Simulations showed that wild-type individuals had exposures at the bottom of therapeutic range, while slower metabolizers were overexposed. Conclusions Dosage guidelines for African children should take into consideration the combined effect of SNPs CYP2B6 516G>T and 983T>C. [ABSTRACT FROM AUTHOR]

The article offers information on nanomedicine publications created to publish development in nanotechnology to solve problems in medicine. It mentions of failure of regulatory agencies like, the U.S. Food and Drug Administration (FDA) and European Medicines Agency, to regulate nanoscale technologies and apply it to drugs. It mentions of the British Society for Nanomedicine, registered charity that aims to move the nanomedicine field forward.