Tacrolimus capsules contain the drug as the amorphous form. It is well known that drug crystallinity is a risk factor for the performance of amorphous formulations. This study investigated the impact of varying levels of crystalline drug on the pharmacokinetics of tacrolimus following oral dosing of a 5 mg capsule under fasting conditions. Two treatments with percent crystallinity of 20% and 50% were achieved by exposing a marketed generic tacrolimus product to open dish storage conditions of 35 °C and 75% relative humidity (RH) for up to 20 days. Crystallinity was monitored with X-ray powder diffraction. Prograf®, the reference listed drug (RLD), an amorphous generic drug product, and generic drug products containing 20% and 50% crystalline tacrolimus were evaluated. All four treatments were administered to healthy participants in a randomized, single-dose, four-treatment, four-period, four-way crossover study. Blood sampling occurred over 24 h. The amorphous generic tacrolimus product was determined not to be bioequivalent to the RLD. The capsules containing both 20% and 50% crystalline tacrolimus also failed the bioequivalence recommendations when compared to the amorphous generic or to the RLD. Both levels of crystalline tacrolimus resulted in BE failure for both Cmax and AUC parameters. The impact of tacrolimus crystallization was greater for maximum blood concentration (Cmax) values relative to the area-under-the-curve (AUC) values. This study demonstrates that crystalline tacrolimus formed in a marketed generic product and these changes resulted in variable pharmacokinetics which could be of significant clinical concern.
ABSTRACTTriple-negative breast cancer (TNBC) is an aggressive form of breast cancer associated with an early age of onset, greater propensity towards metastasis, and poorer clinical outcomes. It accounts for 10% to 20% of newly diagnosed breast cancer cases and disproportionately affects individuals from the African American race. While TNBC is sensitive to chemotherapy, it is also prone to relapse. This is because chemotherapy successfully targets the primary TNBC tumor cell but often fails to target the subpopulation of TNBC stem cells. TNBC stem cells display cancerous traits such as cell cycle progression, survival, proliferation, apoptosis inhibition, and epithelial-mesenchymal transition. To study the cancer initiating behavior of the TNBC stem cells, we studied their underlying signaling pathways using Boolean networks(BN). BNs are effective in capturing the causal interactions taking place in signaling pathways. We built the BN from the pathway literature and used it to evaluate the efficacies of eleven targeted inhibitory drugs in suppressing cancer-promoting genes. We simulated the BN when the pathways had single or multiple mutations, with a maximum of three mutations at a time. Our findings indicated thatSTAT3, GLI, andNF-κBare the most optimal targets for inhibition. These genes are known regulators of the cancer-promoting genes in the pathway,hence our model agrees with the existing biological literature. Therefore inhibiting these three genes has the potential to prevent TNBC relapse. Additionally, our studies found that drug efficacies decreased as mutations increased in the pathway. Furthermore, we noticed that combinations of drugs performed better than single drugs.
BACKGROUND:Cardiovascular mortality in patients receiving dialysis remains unacceptably high, with unexplained ancestry differences suggesting a genetic component. METHODS:We analyzed DNA samples from 37% of subjects enrolled in the EValuation Of Cinacalcet Hydrochloride (HCl) Therapy to Lower CardioVascular Events (EVOLVE) trial, a randomized trial conducted in patients receiving hemodialysis with secondary hyperparathyroidism, comparing cinacalcet to placebo on a background of usual care. DNA was analyzed for single-nucleotide polymorphisms (SNPs) in the genes encoding the angiotensin-converting enzyme receptor type I (AGTR1) and angiotensin-converting enzyme (ACE). Survival analyses were conducted separately in European Ancestry (EA) and African Ancestry (AfAn) due to known differences in cardiovascular events, minor alleles for the same variant and the frequency of minor alleles. Our primary determination was a meta-analysis across both races. RESULTS:Meta-analysis showed significant associations between rs5186 in AGTR1 and increased rates by 25-34% for the primary endpoint (composite of death or nonfatal myocardial infarction, hospitalization for unstable angina, heart failure or peripheral vascular event), all-cause mortality, cardiovascular mortality and heart failure; all P < 0.001. Three correlated SNPs in ACE were associated with lower rates of sudden cardiac death (SCD) in EA samples. One ACE SNP, rs4318, only found in the AfAn samples, was associated with a lower rate of SCD in the AfAn samples. CONCLUSIONS:The C allele in rs5186 in AGTR1 was associated with higher rates of death and major cardiovascular events in a meta-analysis of EA and AfAn patients with end-stage kidney disease. SNPs in ACE were associated with SCD.
Background: Tramadol and codeine are metabolized by CYP2D6 and are subject to drug–gene and drug–drug interactions. Methods: This interim analysis examined prescribing behavior and efficacy in 102 individuals prescribed tramadol or codeine while receiving pharmaco-genotyping as part of the INGENIOUS trial (NCT02297126). Results: Within 60 days of receiving tramadol or codeine, clinicians more frequently prescribed an alternative opioid in ultrarapid and poor metabolizers (odds ratio: 19.0; 95% CI: 2.8–160.4) as compared with normal or indeterminate metabolizers (p = 0.01). After adjusting the CYP2D6 activity score for drug–drug interactions, uncontrolled pain was reported more frequently in individuals with reduced CYP2D6 activity (odds ratio: 0.50; 95% CI: 0.25–0.94). Conclusion: Phenoconversion for drug–drug and drug–gene interactions is an important consideration in pharmacogenomic implementation; drug–drug interactions may obscure the potential benefits of genotyping.
AimsErythropoiesis‐stimulating agents used to treat anaemia in patients with chronic kidney disease (CKD) have been associated with cardiovascular adverse events. Hepcidin production, controlled by bone morphogenic protein 6 (BMP6), regulates iron homeostasis via interactions with the iron transporter, ferroportin. High hepcidin levels are thought to contribute to increased iron sequestration and subsequent anaemia in CKD patients. To investigate alternative therapies to erythropoiesis‐stimulating agents for CKD patients, monoclonal antibodies, LY3113593 and LY2928057, targeting BMP6 and ferroportin respectively, were tested in CKD patients.MethodsPreclinical in vitro/vivo data and clinical data in healthy subjects and CKD patients were used to illustrate the translation of pharmacological properties of LY3113593 and LY2928057, highlighting the novelty of targeting these nodes within the hepcidin–ferroportin pathway.ResultsLY2928057 bound ferroportin and blocked interactions with hepcidin, allowing iron efflux, leading to increased serum iron and transferrin saturation levels and increased hepcidin in monkeys and humans. In CKD patients, LY2928057 led to slower haemoglobin decline and reduction in ferritin (compared to placebo). Serum iron increase was (mean [90% confidence interval]) 1.98 [1.46–2.68] and 1.36 [1.22–1.51] fold‐relative to baseline following LY2928057 600 mg and LY311593 150 mg respectively in CKD patients. LY3113593 specifically blocked BMP6 binding to its receptor and produced increases in iron and transferrin saturation and decreases in hepcidin preclinically and clinically. In CKD patients, LY3113593 produced an increase in haemoglobin and reduction in ferritin (compared to placebo).ConclusionLY3113593 and LY2928057 pharmacological effects (serum iron and ferritin) were translated from preclinical‐to‐clinical development. Such interventions may lead to new CKD anaemia treatments.
Applying data mining and machine learning (ML) techniques to clinical data might identify predictive biomarkers for diabetic nephropathy (DN), a common complication of type 2 diabetes mellitus (T2DM). A retrospective analysis of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial was intended to identify such factors using ML. The longitudinal data were stratified by time after patient enrollment to differentiate early and late predictors. Our results showed that Random Forest and Simple Logistic Regression methods exhibited the best performance among the evaluated algorithms. Baseline values for glomerular filtration rate (GFR), urinary creatinine, urinary albumin, potassium, cholesterol, low-density lipoprotein, and urinary albumin to creatinine ratio were identified as DN predictors. Early predictors were the baseline values of GFR, systolic blood pressure, as well as fasting plasma glucose (FPG) and potassium at month 4. Changes per year in GFR, FPG, and triglycerides were recognized as predictors of late development. In conclusion, ML-based methods successfully identified predictive factors for DN among patients with T2DM.
Background: Elevated serum concentrations of fibroblast growth factor 23 (FGF23) are associated with cardiovascular mortality in patients with chronic kidney disease and those undergoing dialysis. Objectives: We tested the hypotheses that polymorphisms in FGF23, its co-receptor alpha-klotho (KL), and/or FGF23 receptors (FGFR) are associated with cardiovascular events and/or mortality. Methods: We used 1,494 DNA samples collected at baseline from the Evaluation of Cinacalcet HCl Therapy to Lower Cardiovascular Events Trial, in which patients were randomized to the calcimimetic cinacalcet or placebo for the treatment of secondary hyperparathyroidism. We analyzed European and African Ancestry samples separately and then combined summary statistics to perform a meta-analysis. We evaluated single-nucleotide polymorphisms (SNPs) in FGF23, KL, and FGFR4 as the key exposures of interest in proportional hazards (Cox) regression models using adjudicated endpoints (all-cause and cardiovascular mortality, sudden cardiac death, and heart failure [HF]) as the outcomes of interest. Results: rs11063112 in FGF23 was associated with cardiovascular mortality (risk allele = A, hazard ratio [HR] 1.32, meta-p value = 0.004) and HF (HR 1.40, meta-p value = 0.007). No statistically significant associations were observed between FGF23 rs13312789 and SNPs in FGFR4 or KL genes and the outcomes of interest. Conclusions: rs11063112 was associated with HF and cardiovascular mortality in patients receiving dialysis with moderate to severe secondary hyperparathyroidism.
Hypertension and chronic kidney disease are inextricably linked. Hypertension is a well-recognized contributor to chronic kidney disease progression and, in turn, renal disease potentiates hypertension. A generalized approach to drug selection and dosage has not proven effective in managing these conditions, in part, because patients with heterogeneous kidney disease and hypertension etiologies are frequently grouped according to functional or severity classifications. Genetic testing may serve as an important tool in the armamentarium of clinicians who embrace precision medicine. Increasing scientific evidence has supported the utilization of genomic information to select efficacious antihypertensive therapy and understand hereditary contributors to chronic kidney disease progression. Given the wide array of antihypertensive agents available and diversity of genetic renal disease predictors, a panel-based approach to genotyping may be an efficient and economic means of establishing an individualized blood pressure response profile for patients with various forms of chronic kidney disease and hypertension. In this manuscript, we discuss the validation process of a Clinical Laboratory Improvement Amendments-approved genetic test to relay information on 72 genetic variants associated with kidney disease progression and hypertension therapy. These genomic-based interventions, in addition to routine clinical data, may help inform physicians to provide personalized therapy.
Pharmacogenomics, relating an individual's genetics to their response to medications, is a component of precision medicine. Many drug–gene(s) interactions have been identified. More than 140 US Food and Drug Administration–approved drugs have pharmacogenomic information in their labeling. Genes of interest, pharmacogenes, are related to both pharmacokinetics and pharmacodynamics. Pharmacogenes code for drug-metabolizing enzymes, transporters, receptors, enzyme targets, and other proteins. Utilizing an individual's genetics relative to safe and effective drug therapy is aimed at identifying the correct drug and drug dose early in therapy. Improved approaches to understanding disease risk and the applications of pharmacogenomics are poised to improve the health of individuals. Pharmacists, through the application of specific competencies in genomics/pharmacogenomics, are positioned to lead the way in the implementation of this precision medicine component across practice settings.
Pharmacogenetic testing can help identify primary care patients at increased risk for medication toxicity, poor response or treatment failure and inform drug therapy. While testing availability is increasing, providers are unprepared to routinely use pharmacogenetic testing for clinical decision-making. Practice-based resources are needed to overcome implementation barriers for pharmacogenetic testing in primary care.The NHGRI's IGNITE I Network (Implementing GeNomics In pracTicE; www.ignite-genomics.org) explored practice models, challenges and implementation barriers for clinical pharmacogenomics. Based on these experiences, we present a stepwise approach pharmacogenetic testing in primary care: patient identification; pharmacogenetic test ordering; interpretation and application of test results, and patient education. We present clinical factors to consider, test-ordering processes and resources, and provide guidance to apply test results and counsel patients. Practice-based resources such as this stepwise approach to clinical decision-making are important resources to equip primary care providers to use pharmacogenetic testing.
Background. The American Society of Nephrology's (ASN) Workforce Committee created a unique program called the Kidney Mentoring and Awareness Program for Students to engage medical students in the fight against kidney diseases and interest them in careers in nephrology. Methods. The program provided a framework and 2 years of funding to three medical schools to organize and carry out health screenings in underserved areas of their communities as well as a structure for student mentoring by the practicing nephrologists. Results. The Workforce Committee identified three medical schools (Emory University, Atlanta, GA; Indiana University, Indianapolis, IN and University of Louisville, Louisville, KY) and engaged faculty at each school to serve as advisors. The ASN committed funding to the groups for 2 years, after which the groups became self-sufficient. Three nephrologists participated in each chapter, building on existing relationships with community groups to identify sites and carry out kidney screening events. Conclusions. We report here the experience of those chapters and a blueprint for other schools interested in setting up a similarly structured program to interest students in nephrology while working with community groups to spread awareness of the major underlying causes of kidney disease.
ObjectivesImplementing new programs to support precision medicine in clinical settings is a complex endeavor. We describe challenges and potential solutions based on the Indiana GENomics Implementation: an Opportunity for the Underserved (INGenious) program at Eskenazi Health—one of six sites supported by the Implementing GeNomics In pracTicE network grant of the National Institutes of Health/National Human Genome Research Institute. INGenious is an implementation of a panel of genomic tests.MethodsWe conducted a descriptive case study of the implementation of this pharmacogenomics program, which has a wide scope (14 genes, 27 medications) and a diverse population (patients who often have multiple chronic illnesses, in a large urban safety-net hospital and its outpatient clinics).ChallengesWe placed the clinical pharmacogenomics implementation challenges into six categories: patient education and engagement in care decision making; clinician education and changes in standards of care; integration of technology into electronic health record systems; translational and implementation sciences in real-world clinical environments; regulatory and reimbursement considerations, and challenges in measuring outcomes. A cross-cutting theme was the need for careful attention to workflow. Our clinical setting, a safety-net health care system, presented some distinctive challenges. Patients often had multiple chronic illnesses and sometimes were taking more than one pharmacogenomics-relevant medication. Reaching patients for recruitment or follow-up was another challenge.ConclusionsNew, large-scale endeavors in health care are challenging. A description of the challenges that we encountered and the approaches that we adopted to address them may provide insights for those who implement and study innovations in other health care systems.
BACKGROUND AND OBJECTIVES:We tested the hypothesis that single nucleotide polymorphisms (SNPs) in the calcium-sensing receptor (CASR) alter the response to the calcimimetic cinacalcet. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS:We analyzed DNA samples in the Evaluation of Cinacalcet HCl Therapy to Lower Cardiovascular Events (EVOLVE) trial, a randomized trial comparing cinacalcet to placebo on a background of usual care. Of the 3883 patients randomized, 1919 (49%) consented to DNA collection, and samples from 1852 participants were genotyped for 18 CASR polymorphisms. The European ancestry (EA; n=1067) and African ancestry (AfAn; n=405) groups were assessed separately. SNPs in CASR were tested for their association with biochemical measures of mineral metabolism at baseline, percent change from baseline to 20 weeks, and risk of clinical fracture as dependent variables. RESULTS:There were modest associations of CASR SNPs with increased baseline serum parathyroid hormone and bone alkaline phosphatase primarily with the minor allele in the EA group (all P≤0.03), but not in the AfAn sample. In contrast, there was a modest association of decreased baseline serum calcium and FGF23 with CASR SNPs (P=0.04) primarily with the minor allele in the AfAn but not in the EA sample. The minor allele of two SNPs was associated with decreased percent reduction in parathyroid hormone from baseline to 20 weeks in the EA population (P<0.04) and this was not altered with cinacalcet. In both EA and AfAn, the same SNP (rs9740) was associated with decreased calcium with cinacalcet treatment (EA and AfAn P≤0.03). Three SNPs in high linkage disequilibrium were associated with a higher risk of clinical fracture that was attenuated by cinacalcet treatment in the EA sample (P<0.04). CONCLUSIONS:These modest associations, if validated, may provide explanations for differences in CKD-mineral bone disorder observed in EA and AfAn populations, and for differential biochemical responses to calcimimetics.
BACKGROUND:Aldosterone acts to restrain the extracellular potassium (K+) concentration. Blacks have on average lower plasma aldosterone concentrations (PACs) than Whites. Whether this ethnic difference is associated with similar changes in the concentration of K+ is unclear. METHODS:Subjects were Blacks and Whites from an observational study of blood pressure regulation. PAC was known to be significantly lower in Blacks than Whites. We sought to test the hypothesis that the concentration of K+ remains constant despite variability in PAC. Initial enrollment took place in childhood in 1986. Some of the original enrollees were studied again in adulthood: 160 healthy Blacks and 271 healthy Whites (ages 5 to 39 years; all were studied as children and as adults). RESULTS:Plasma renin activity [a biomarker of angiotensin II and, more proximally, extracellular fluid volume (ECFV)] and PAC were lower in Blacks (P < 0.0354 and P < 0.001, respectively, for all ages). At the same time no ethnic difference in levels of K+ was observed regardless of age. Plasma K+ concentration and PAC associated differently based on ethnicity: PAC increased in Blacks by 1.5-2.0 and in Whites by 2.3-3.0 ng/dl per mmol/l increase in K+ (P < 0.001). CONCLUSIONS:Lower aldosterone levels in Blacks did not translate into higher K+ concentrations. We speculate that reaching the right concentration of K+ was an endpoint of aldosterone production in the presence of varying levels of ECFV and angiotensin II.
BACKGROUND:Patterns of healthcare encounters by patients in each stage of chronic kidney disease (CKD) have not been fully described.OBJECTIVE:This study describes patterns of healthcare resource use by patients with CKD.DESIGN:A retrospective descriptive design was used.PARTICIPANTS:Patients with Stages 1-5 CKD were identified in five existing de-identified healthcare insurance claims databases in the United States using codes from the International Classification of Diseases (ICD-9-CM).MEASUREMENTS:The databases contained more than 23,660,000 claims records from over 11 million subscribers who were continuously enrolled in a single 2014 health plan. All CKD patients' 2014 claims were extracted, yielding 1,987 unique people with 110,594 healthcare encounters.RESULTS:Healthcare resources are used to manage the causes of CKD and its multiple effects on health, and thus the number of healthcare encounters among people with more advanced disease was, as expected, relatively higher. There were more hospitalisations, emergency department visits and specialist encounters in this group. Surprisingly, however, even people in earlier stages of kidney disease experienced a median of 14-17 healthcare encounters during a single calendar year.CONCLUSIONS:Understanding patterns of healthcare encounters provides important information about the transition experiences of patients with CKD. Exploring ways to reduce the risks associated with transitions in care may prevent problems with home medication management, frequent emergency department visits and potentially avoidable hospitalisations.
BACKGROUNDWe developed and beta-tested a patient-centered medication management application, PresRx optical character recognition (OCR), a mobile health (m-health) tool that auto-populates drug name and dosing instructions directly from patients' medication labels by OCR.MATERIALS AND METHODSWe employed a single-subject design study to evaluate PresRx OCR for three outcomes: (1) accuracy of auto-populated medication dosing instructions, (2) acceptability of the user interface, and (3) patients' adherence to chronic medications.RESULTSEight patients beta-tested PresRx OCR. Five patients used the software for ≥6 months, and four completed exit interviews (n = 4 completers). At baseline, patients used 3.4 chronic prescription medications and exhibited moderate-to-high adherence rates. Accuracy of auto-populated information by OCR was 95% for drug name, 98% for dose, and 96% for frequency. Study completers rated PresRx OCR 74 on the System Usability Scale, where scores ≥70 indicate an acceptable user interface (scale 0-100). Adherence rates measured by PresRx OCR were high during the first month of app use (93%), but waned midway through the 6-month testing period (78%). Compared with pharmacy fill rates, PresRx OCR underestimated adherence among completers by 3%, while it overestimated adherence among noncompleters by 8%.DISCUSSIONResults suggest smartphone applications supporting medication management are feasible and accurately assess adherence compared with objective measures. Future efforts to improve medication-taking behavior using m-health tools should target specific patient populations and leverage common application programming interfaces to promote generalizability.CONCLUSIONSOur medication management application PresRx OCR is innovative, acceptable for patient use, and accurately tracks medication adherence.
Knowledge is a prerequisite for changing behavior, and is useful for improving outcomes and reducing mortality rates in patients diagnosed with chronic kidney disease (CKD). The purpose of this article is to describe baseline CKD knowledge and awareness obtained as part of a larger study testing the feasibility of a self-management intervention. Thirty patients were recruited who had CKD Stage 3 with coexisting diabetes and hypertension. Fifty-four percent of the sample were unaware of their CKD diagnosis. Participants had a moderate amount of CKD knowledge. This study suggests the need to increase knowledge in patients with CKD Stage 3 to aid in slowing disease progression.
Triamterene, because of its potassium-sparing properties, is frequently used in combination with hydrochlorothiazide (HCTZ) to treat patients with hypertension. By inhibiting the epithelial sodium channel (ENaC) in the cortical collecting duct, triamterene reduces potassium secretion, thus reducing the risk of hypokalemia. Whether triamterene has an independent effect on blood pressure (BP) has not been well studied. To determine if triamterene provides an effect to further lower BP in patients treated with HCTZ. We conducted an observational study using electronic medical record data from the Indiana Network for Patient Care. Participants were 17,291 patients with the diagnosis of hypertension between 2004 and 2012. BP was the primary outcome. We compared the BP between patients who were taking HCTZ, with and without triamterene, either alone or in combination with other antihypertensive medications, by using a propensity score analysis. For each medication combination, we estimated the propensity score (i.e., probability) of a patient receiving triamterene using a logistic regression model. Patients with similar propensity scores were stratified into subclasses and BP was compared between those taking triamterene or not within each subclass; the effect of triamterene was then assessed by combining BP differences estimated from all subclasses. The mean systolic BP in the triamterene + HCTZ group was 3.8 mmHg lower than in the HCTZ only group (p < 0.0001); systolic BP was similarly lower for patients taking triamterene with other medication combinations. Systolic BP reduction was consistently observed for different medication combinations. The range of systolic BP reduction was between 1 and 4 mm Hg, depending on the concurrently used medications. In the present study, triamterene was found to enhance the effect of HCTZ to lower BP. In addition to its potassium-sparing action, triamterene's ability to lower BP should also be considered.
Objective: Prior to implementing a trial to evaluate the economic costs and clinical outcomes of pharmacogenetic testing in a large safety net health care system, we determined the number of patients taking targeted medications and their clinical care encounter sites.Methods: Using 1-year electronic medical record data, we evaluated the number of patients who had started one or more of 30 known pharmacogenomically actionable medications and the number of care encounter sites the patients had visited.Results: Results showed 7039 unique patients who started one or more of the target medications within a 12-month period with visits to 73 care sites within the system.Conclusion: Findings suggest that the type of large-scale, multi-drug, multi-gene approach to pharmacogenetic testing we are planning is widely relevant, and successful implementation will require wide-scale education of prescribers and other personnel involved in medication dispensing and handling.