Solute carrier (SLC) transporters - a family of more than 300 membrane-bound proteins that facilitate the transport of a wide array of substrates across biological membranes - have important roles in ...physiological processes ranging from the cellular uptake of nutrients to the absorption of drugs and other xenobiotics. Several classes of marketed drugs target well-known SLC transporters, such as neurotransmitter transporters, and human genetic studies have provided powerful insight into the roles of more-recently characterized SLC transporters in both rare and common diseases, indicating a wealth of new therapeutic opportunities. This Review summarizes knowledge on the roles of SLC transporters in human disease, describes strategies to target such transporters, and highlights current and investigational drugs that modulate SLC transporters, as well as promising drug targets.
Implicit motor recalibration allows us to flexibly move in novel and changing environments. Conventionally, implicit recalibration is thought to be driven by errors in predicting the sensory outcome ...of movement (i.e., sensory prediction errors). However, recent studies have shown that implicit recalibration is also influenced by errors in achieving the movement goal (i.e., task errors). Exactly how sensory prediction errors and task errors interact to drive implicit recalibration and, in particular, whether task errors alone might be sufficient to drive implicit recalibration remain unknown. To test this, we induced task errors in the absence of sensory prediction errors by displacing the target mid-movement. We found that task errors alone failed to induce implicit recalibration. In additional experiments, we simultaneously varied the size of sensory prediction errors and task errors. We found that implicit recalibration driven by sensory prediction errors could be continuously modulated by task errors, revealing an unappreciated dependency between these two sources of error. Moreover, implicit recalibration was attenuated when the target was simply flickered in its original location, even though this manipulation did not affect task error - an effect likely attributed to attention being directed away from the feedback cursor. Taken as a whole, the results were accounted for by a computational model in which sensory prediction errors and task errors, modulated by attention, interact to determine the extent of implicit recalibration.
The motor system demonstrates an exquisite ability to adapt to changes in the environment and to quickly reset when these changes prove transient. If similar environmental changes are encountered in ...the future, learning may be faster, a phenomenon known as savings. In studies of sensorimotor learning, a central component of savings is attributed to the explicit recall of the task structure and appropriate compensatory strategies. Whether implicit adaptation also contributes to savings remains subject to debate. We tackled this question by measuring, in parallel, explicit and implicit adaptive responses in a visuomotor rotation task, employing a protocol that typically elicits savings. While the initial rate of learning was faster in the second exposure to the perturbation, an analysis decomposing the 2 processes showed the benefit to be solely associated with explicit re-aiming. Surprisingly, we found a significant decrease after relearning in aftereffect magnitudes during no-feedback trials, a direct measure of implicit adaptation. In a second experiment, we isolated implicit adaptation using clamped visual feedback, a method known to eliminate the contribution of explicit learning processes. Consistent with the results of the first experiment, participants exhibited a marked reduction in the adaptation function, as well as an attenuated aftereffect when relearning from the clamped feedback. Motivated by these results, we reanalyzed data from prior studies and observed a consistent, yet unappreciated pattern of attenuation of implicit adaptation during relearning. These results indicate that explicit and implicit sensorimotor processes exhibit opposite effects upon relearning: Explicit learning shows savings, while implicit adaptation becomes attenuated.
Pharmacogenomics (PGx), examining the effect of genetic variation on interpatient variation in drug disposition and response, has been widely studied for several decades. However, as cost, as well as ...turnaround time associated with PGx testing, has significantly improved, the use of PGx in the clinical setting has been gaining momentum. Nevertheless, challenges have emerged in the broader clinical implementation of PGx. In this review, we will outline current models of PGx delivery and methodologies of evaluation, and discuss clinically relevant PGx tests and associated medications. Additionally, we will describe our approach for the broad implementation of pre-emptive DPYD genotyping in patients taking fluoropyrimidines in Ontario, Canada, as an example of clinically actionable PGx testing with sufficient clinical evidence of patient benefit that can become a new standard of patient care. We will highlight challenges associated with PGx testing, including a lack of diversity in PGx studies as well as general limitations that impact the broad adoption of PGx testing. Lastly, we examine the future of PGx, discussing new clinical targets, methodologies and analysis approaches.
Abstract Warfarin has been the mainstay oral anticoagulant (OAC) medication prescribed for stroke prevention in atrial fibrillation (AF) patients. However, warfarin therapy is challenging because of ...marked interindividual variability in dose and response, requiring frequent monitoring and dose titration. These limitations have prompted the clinical development of new OACs (NOACs) that directly target the coagulation cascade with rapid onset/offset of action, lower risk for drug-drug interactions, and more predictable response. Recently, NOACs dabigatran (direct thrombin inhibitor), and rivaroxaban and apixaban (factor Xa FXa inhibitors) have gained regulatory approval as alternative therapies to warfarin. Though the anticoagulation efficacy of these NOACs has been characterized, differences in their pharmacokinetic and pharmacodynamic profiles have become a significant consideration in terms of drug selection and dosing. In this review, we outline key pharmacokinetic and pharmacodynamic features of each compound and provide guidance on selection and dosing of the 3 NOACs relative to warfarin when considering OAC therapy for AF patients. Importantly, we show that by better understanding the effect of clinical variables such as age, renal function, dosing interval, and drug metabolism (CYP3A4) and transport (P-glycoprotein), we might be able to better predict the risk for sub- and supratherapeutic anticoagulation response and individualize OAC selection and dosing.
To analytically and clinically validate microsatellite instability (MSI) detection using cell-free DNA (cfDNA) sequencing.
Pan-cancer MSI detection using Guardant360 was analytically validated ...according to established guidelines and clinically validated using 1,145 cfDNA samples for which tissue MSI status based on standard-of-care tissue testing was available. The landscape of cfDNA-based MSI across solid tumor types was investigated in a cohort of 28,459 clinical plasma samples. Clinical outcomes for 16 patients with cfDNA MSI-H gastric cancer treated with immunotherapy were evaluated.
cfDNA MSI evaluation was shown to have high specificity, precision, and sensitivity, with a limit of detection of 0.1% tumor content. In evaluable patients, cfDNA testing accurately detected 87% (71/82) of tissue MSI-H and 99.5% of tissue microsatellite stable (863/867) for an overall accuracy of 98.4% (934/949) and a positive predictive value of 95% (71/75). Concordance of cfDNA MSI with tissue PCR and next-generation sequencing was significantly higher than IHC. Prevalence of cfDNA MSI for major cancer types was consistent with those reported for tissue. Finally, robust clinical activity of immunotherapy treatment was seen in patients with advanced gastric cancer positive for MSI by cfDNA, with 63% (10/16) of patients achieving complete or partial remission with sustained clinical benefit.
cfDNA-based MSI detection using Guardant360 is highly concordant with tissue-based testing, enabling highly accurate detection of MSI status concurrent with comprehensive genomic profiling and expanding access to immunotherapy for patients with advanced cancer for whom current testing practices are inadequate.
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This white paper provides updated International Transporter Consortium (ITC) recommendations on transporters that are important in drug development following the 3rd ITC workshop. New additions ...include prospective evaluation of organic cation transporter 1 (OCT1) and retrospective evaluation of organic anion transporting polypeptide (OATP)2B1 because of their important roles in drug absorption, disposition, and effects. For the first time, the ITC underscores the importance of transporters involved in drug‐induced vitamin deficiency (THTR2) and those involved in the disposition of biomarkers of organ function (OAT2 and bile acid transporters).
There is an unmet need for a treatment for psoriasis that results in complete skin clearance with a reliably quick response. Bimekizumab is a monoclonal IgG1 antibody that selectively inhibits ...interleukin (IL)-17F in addition to IL-17A. We aimed to compare the efficacy and safety of bimekizumab with placebo and ustekinumab in patients with moderate to severe plaque psoriasis over 52 weeks.
BE VIVID was a multicentre, randomised, double-blind, active comparator and placebo controlled phase 3 trial done across 105 sites (clinics, hospitals, research units, and private practices) in 11 countries in Asia, Australia, Europe, and North America. Adults aged 18 years or older with moderate to severe plaque psoriasis (Psoriasis Area and Severity Index PASI score ≥12, ≥10% body surface area affected by psoriasis, and Investigator's Global Assessment IGA score ≥3 on a five point scale) were included. Randomisation was stratified by geographical region and previous exposure to biologics; patients, investigators, and sponsors were masked to treatment assignment. Patients were randomly assigned (4:2:1) using an interactive response technology to bimekizumab 320 mg every 4 weeks, ustekinumab 45 mg or 90 mg (baseline weight-dependent dosing) at weeks 0 and 4, then every 12 weeks, or placebo every 4 weeks. At week 16, patients receiving placebo switched to bimekizumab 320 mg every 4 weeks. All study treatments were administered as two subcutaneous injections. Coprimary endpoints were the proportion of patients with 90% improvement in the PASI (PASI90) and the proportion of patients with an IGA response of clear or almost clear (score 0 or 1) at week 16 (non-responder imputation). Efficacy analyses included the intention-to-treat population; safety analysis included patients who received at least one dose of study treatment. This trial was registered at ClinicalTrials.gov, NCT03370133 (completed).
Between Dec 6, 2017, and Dec 13, 2019, 735 patients were screened and 567 were enrolled and randomly assigned (bimekizumab 320 mg every 4 weeks n=321, ustekinumab 45 mg or 90 mg every 12 weeks n=163, placebo n=83). At week 16, 273 (85%) of 321 patients in the bimekizumab group had PASI90 versus 81 (50%) of 163 in the ustekinumab group (risk difference 35 95% CI 27–43; p<0·0001) and four (5%) of 83 in the placebo group (risk difference 80 74–86; p<0·0001). At week 16, 270 (84%) patients in the bimekizumab group had an IGA response versus 87 (53%) in the ustekinumab group (risk difference 30 95% CI 22–39; p<0·0001) and four (5%) in the placebo group (risk difference 79 73–85; p<0·0001). Over 52 weeks, serious treatment-emergent adverse events were reported in 24 (6%) of 395 patients in the bimekizumab group (including those who switched from placebo at week 16) and 13 (8%) of 163 in the ustekinumab group.
Bimekizumab was more efficacious than ustekinumab and placebo in the treatment of moderate to severe plaque psoriasis. The bimekizumab safety profile was consistent with that observed in previous studies.
UCB Pharma.
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