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1.
Diabetes Obes Metab ; 22(3): 427-433, 2020 03.
Article in English | MEDLINE | ID: mdl-31858718

ABSTRACT

AIM: To confirm the observed reduction in HbA1c for the 2.5 mg dose in EASE-3 by modelling and simulation analyses. MATERIALS AND METHODS: Independent of data from EASE-3 that tested 2.5 mg, we simulated the effect of a 2.5 mg dose through patient-level, exposure-response modelling in the EASE-2 clinical study. A primary semi-mechanistic model evaluated efficacy considering clinical insulin dose adjustments made after treatment initiation that potentially limited HbA1c reductions. The model was informed by pharmacokinetic, insulin dose, mean daily glucose and HbA1c data, and was verified by comparing the simulations with the observed HbA1c change in EASE-3. One of two empagliflozin phase 3 trials in type 1 diabetes (EASE-3 but not EASE-2) included a lower 2.5 mg dose. A placebo-corrected HbA1c reduction of 0.28% was demonstrated without the increased risk of diabetic ketoacidosis observed at higher doses (10 mg and 25 mg). Since only one trial included the lower dose, we aimed to confirm the observed reduction in HbA1c for the 2.5 mg dose by modelling and simulation analyses. RESULTS: The simulated 26-week mean HbA1c change was -0.41% without insulin dose adjustment and -0.29% at 26 weeks with insulin dose adjustment. A simplified (descriptive) model excluding insulin dose and mean daily glucose confirmed the -0.29% HbA1c change that would have been observed had the EASE-2 population received a 2.5 mg dose for 26/52 weeks. CONCLUSIONS: The HbA1c benefit of low-dose empagliflozin directly observed in the EASE-3 trial was confirmed by two modelling and simulation approaches.


Subject(s)
Diabetes Mellitus, Type 1 , Insulin , Benzhydryl Compounds/adverse effects , Diabetes Mellitus, Type 1/drug therapy , Dose-Response Relationship, Drug , Double-Blind Method , Drug Therapy, Combination , Glucosides , Glycated Hemoglobin , Humans , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use
3.
CMAJ ; 187(11): 799-804, 2015 Aug 11.
Article in English | MEDLINE | ID: mdl-26009583

ABSTRACT

BACKGROUND: Readmissions after hospital discharge are common and costly, but prediction models are poor at identifying patients at high risk of readmission. We evaluated the impact of frailty on readmission or death within 30 days after discharge from general internal medicine wards. METHODS: We prospectively enrolled patients discharged from 7 medical wards at 2 teaching hospitals in Edmonton. Frailty was defined by means of the previously validated Clinical Frailty Scale. The primary outcome was the composite of readmission or death within 30 days after discharge. RESULTS: Of the 495 patients included in the study, 162 (33%) met the definition of frailty: 91 (18%) had mild, 60 (12%) had moderate, and 11 (2%) had severe frailty. Frail patients were older, had more comorbidities, lower quality of life, and higher LACE scores at discharge than those who were not frail. The composite of 30-day readmission or death was higher among frail than among nonfrail patients (39 [24.1%] v. 46 [13.8%]). Although frailty added additional prognostic information to predictive models that included age, sex and LACE score, only moderate to severe frailty (31.0% event rate) was an independent risk factor for readmission or death (adjusted odds ratio 2.19, 95% confidence interval 1.12-4.24). INTERPRETATION: Frailty was common and associated with a substantially increased risk of early readmission or death after discharge from medical wards. The Clinical Frailty Scale could be useful in identifying high-risk patients being discharged from general internal medicine wards.


Subject(s)
Cause of Death , Patient Discharge/statistics & numerical data , Patient Outcome Assessment , Patient Readmission/statistics & numerical data , Severity of Illness Index , Adult , Aged , Aged, 80 and over , Canada , Cohort Studies , Female , Follow-Up Studies , Frail Elderly , Hospitalization/statistics & numerical data , Hospitals, Teaching , Humans , Length of Stay , Male , Middle Aged , Predictive Value of Tests , Prospective Studies , Risk Assessment , Survival Analysis , Time Factors
4.
Dig Dis Sci ; 60(11): 3318-28, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26138654

ABSTRACT

BACKGROUND AND AIMS: The prevalence of nonalcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) is increasing at an alarming rate. The role of bile acids in the development and progression of NAFLD to NASH and cirrhosis is poorly understood. This study aimed to quantify the bile acid metabolome in healthy subjects and patients with non-cirrhotic NASH under fasting conditions and after a standardized meal. METHODS: Liquid chromatography tandem mass spectroscopy was used to quantify 30 serum and 16 urinary bile acids from 15 healthy volunteers and 7 patients with biopsy-confirmed NASH. Bile acid concentrations were measured at two fasting and four post-prandial time points following a high-fat meal to induce gallbladder contraction and bile acid reabsorption from the intestine. RESULTS: Patients with NASH had significantly higher total serum bile acid concentrations than healthy subjects under fasting conditions (2.2- to 2.4-fold increase in NASH; NASH 2595-3549 µM and healthy 1171-1458 µM) and at all post-prandial time points (1.7- to 2.2-fold increase in NASH; NASH 4444-5898 µM and healthy 2634-2829 µM). These changes were driven by increased taurine- and glycine-conjugated primary and secondary bile acids. Patients with NASH exhibited greater variability in their fasting and post-prandial bile acid profile. CONCLUSIONS: Results indicate that patients with NASH have higher fasting and post-prandial exposure to bile acids, including the more hydrophobic and cytotoxic secondary species. Increased bile acid exposure may be involved in liver injury and the pathogenesis of NAFLD and NASH.


Subject(s)
Bile Acids and Salts/blood , Metabolomics , Non-alcoholic Fatty Liver Disease/blood , Adult , Biomarkers/blood , Case-Control Studies , Chromatography, Liquid , Discriminant Analysis , Fasting/blood , Female , Humans , Least-Squares Analysis , Male , Metabolomics/methods , Middle Aged , Non-alcoholic Fatty Liver Disease/diagnosis , Postprandial Period , Tandem Mass Spectrometry , Time Factors
5.
CPT Pharmacometrics Syst Pharmacol ; 13(2): 192-207, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38017712

ABSTRACT

Bayesian estimation is a powerful but underutilized tool for answering drug development questions. In this tutorial, the principles of Bayesian model development, assessment, and prior selection will be outlined. An example pharmacokinetic (PK) model will be used to demonstrate the implementation of Bayesian modeling using the nonlinear mixed-effects modeling software NONMEM.


Subject(s)
Nonlinear Dynamics , Software , Humans , Bayes Theorem , Models, Biological
6.
Ther Innov Regul Sci ; 2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39373938

ABSTRACT

Bayesian borrowing analyses have an important role in the design and analysis of pediatric trials. This paper describes use of a prespecified Pharmacometrics Enhanced Bayesian Borrowing (PEBB) analysis that was conducted to overcome an expectation for reduced statistical power in the pediatric DINAMO trial due to a greater than expected variability in the primary endpoint. The DINAMO trial assessed the efficacy and safety of an empagliflozin dosing regimen versus placebo and linagliptin versus placebo on glycemic control (change in HbA1c over 26 weeks) in young people with type 2 diabetes (T2D). Previously fitted pharmacokinetic and exposure-response models for empagliflozin and linagliptin based on available historical data in adult and pediatric patients with T2D were used to simulate participant data and derive the informative component of a Bayesian robust mixture prior distribution. External experts and representatives from the U.S. Food and Drug Administration provided recommendations to determine the effective sample size of the prior and the weight of the informative prior component. Separate exposure response-based Bayesian borrowing analyses for empagliflozin and linagliptin showed posterior mean and 95% credible intervals that were consistent with the trial results. Sensitivity analyses with a full range of alternative weights were also performed. The use of PEBB in this analysis combined advantages of mechanistic modeling of pharmacometric differences between adults and young people with T2D, with advantages of partial extrapolation through Bayesian dynamic borrowing. Our findings suggest that the described PEBB approach is a promising option to optimize the power for future pediatric trials.

7.
Pharmaceutics ; 13(4)2021 Apr 02.
Article in English | MEDLINE | ID: mdl-33918261

ABSTRACT

In clinical trials, sodium-glucose co-transporter (SGLT) inhibitor use as adjunct to insulin therapy in type 1 diabetes (T1D) provides glucometabolic benefits while diabetic ketoacidosis risk is increased. The SGLT2 inhibitor empagliflozin was evaluated in two phase III trials: EASE-2 and EASE-3. A low, 2.5-mg dose was included in EASE-3 only. As the efficacy of higher empagliflozin doses (i.e., 10 and 25 mg) in T1D has been established in EASE-2 and EASE-3, a modeling and simulation approach was used to generate additional supportive evidence on efficacy for the 2.5-mg dose. We present the methodology behind the development and validation of two modeling and simulation frameworks: M-EASE-1, a semi-mechanistic model integrating information on insulin, glucose, and glycated hemoglobin; and M-EASE-2, a descriptive model informed by prior information. Both models were developed independently of data from EASE-3. Simulations based on these models assessed efficacy in untested clinical trial scenarios. In this manner, the models provide supportive evidence for efficacy of low-dose empagliflozin 2.5 mg in patients with T1D, illustrating how pharmacometric analyses can support efficacy assessments in the context of limited data.

8.
Transl Oncol ; 14(3): 101016, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33465745

ABSTRACT

Cancer of Unknown Primary (CUP) occurs in 3-5% of patients when standard histological diagnostic tests are unable to determine the origin of metastatic cancer. Typically, a CUP diagnosis is treated empirically and has very poor outcomes, with median overall survival less than one year. Gene expression profiling alone has been used to identify the tissue of origin but struggles with low neoplastic percentage in metastatic sites which is where identification is often most needed. MI GPSai, a Genomic Prevalence Score, uses DNA sequencing and whole transcriptome data coupled with machine learning to aid in the diagnosis of cancer. The algorithm trained on genomic data from 34,352 cases and genomic and transcriptomic data from 23,137 cases and was validated on 19,555 cases. MI GPSai predicted the tumor type in the labeled data set with an accuracy of over 94% on 93% of cases while deliberating amongst 21 possible categories of cancer. When also considering the second highest prediction, the accuracy increases to 97%. Additionally, MI GPSai rendered a prediction for 71.7% of CUP cases. Pathologist evaluation of discrepancies between submitted diagnosis and MI GPSai predictions resulted in change of diagnosis in 41.3% of the time. MI GPSai provides clinically meaningful information in a large proportion of CUP cases and inclusion of MI GPSai in clinical routine could improve diagnostic fidelity. Moreover, all genomic markers essential for therapy selection are assessed in this assay, maximizing the clinical utility for patients within a single test.

9.
Mol Cancer Ther ; 19(12): 2634-2640, 2020 12.
Article in English | MEDLINE | ID: mdl-33037134

ABSTRACT

Goblet cell carcinoid (GCC) is a distinct subtype of appendiceal neoplasm that exhibits unique clinical and pathologic features. We aimed to reveal the molecular profiles of GCC compared with other appendiceal tumors, such as adenocarcinomas and neuroendocrine tumors. A total of 495 appendiceal tumor samples (53 GCCs, 428 adenocarcinomas, and 14 neuroendocrine tumors) were tested with next-generation sequencing (NGS) on a 592-gene panel and IHC. Microsatellite instability (MSI)/mismatch repair (MMR) status was tested with a combination of NGS, IHC, and fragment analyses. Tumor mutational burden (TMB) was evaluated by NGS, and PD-L1 expression was tested by IHC (SP142). The most prevalent mutated genes within GCCs were TP53 (24.0%), ARID1A (15.4%), SMAD4 (9.4%), and KRAS (7.5%). Pathway-specific alterations were dominantly observed in cell cycle, MAPK, epigenetic, and TGFß signaling pathways. GCCs as compared with adenocarcinomas exhibited significantly lower mutation rates in KRAS, GNAS, and APC, and significantly higher mutation rates in CDH1, CHEK2, CDC73, ERCC2, and FGFR2 GCCs as compared with neuroendocrine tumors showed significantly lower mutation rates in KRAS, APC, BRCA2, and FANCA In GCCs, MSI high/MMR deficient, TMB high (≥17 mutations/Mb), and PD-L1 expression were seen in 0.0%, 0.0%, and 2.0% of tumors, respectively. No significant differences were observed in any immunotherapy-related markers examined when compared with adenocarcinomas and neuroendocrine tumors. In conclusion, GCCs had considerably distinct mutational profiles compared with appendiceal adenocarcinomas and neuroendocrine tumors. Understanding these molecular characteristics may be critical for the development of novel and more effective treatment strategies for GCC.


Subject(s)
Appendiceal Neoplasms/diagnosis , Appendiceal Neoplasms/etiology , Carcinoid Tumor/diagnosis , Carcinoid Tumor/etiology , Disease Susceptibility , Adult , Aged , Alleles , Biomarkers, Tumor , Female , Gene Expression Profiling , Genetic Predisposition to Disease , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Mutation , Mutation Rate , Neuroendocrine Tumors/diagnosis , Neuroendocrine Tumors/etiology
10.
Clin Cancer Res ; 25(10): 3096-3103, 2019 05 15.
Article in English | MEDLINE | ID: mdl-30692096

ABSTRACT

PURPOSE: The natural history and prognosis of appendiceal adenocarcinomas differ from those of adenocarcinomas arising in other large bowel sites. We aimed to compare the molecular profiles exhibited by appendiceal adenocarcinomas and colorectal cancers, or between the histopathologic subtypes of appendiceal adenocarcinoma. EXPERIMENTAL DESIGN: A total of 183 samples from appendiceal adenocarcinoma [46 adenocarcinoma, not otherwise specified (NOS), 66 pseudomyxoma peritonei (PMP), 44 mucinous adenocarcinoma (MU), and 27 signet ring cell carcinoma (SR)], 994 from right-sided colorectal cancer (R-CRC), and 1,080 from left-sided CRC (L-CRC) were analyzed by next-generation sequencing (NGS) and IHC markers. Microsatellite instability (MSI) and tumor mutational burden (TMB) were tested by NGS, and programmed death ligand 1 (PD-L1) by IHC. RESULTS: We observed high mutation rates in appendiceal adenocarcinoma samples for KRAS (55%), TP53 (40%), GNAS (31%), SMAD4 (16%), and APC (10%). Appendiceal adenocarcinoma exhibited higher mutation rates in KRAS and GNAS, and lower mutation rates in TP53, APC, and PIK3CA (6%) than colorectal cancers. PMP exhibited much higher mutation rates in KRAS (74%) and GNAS (63%), and much lower mutation rates in TP53 (23%), APC (2%), and PIK3CA (2%) than NOS. Alterations associated with immune checkpoint inhibitor response (MSI-high, TMB-high, PD-L1 expression) showed similar frequency in appendiceal adenocarcinoma compared with L-CRC, but not R-CRC, and those of NOS were higher than other subtypes of appendiceal adenocarcinoma and L-CRC. CONCLUSIONS: Molecular profiling of appendiceal adenocarcinoma revealed different molecular characteristics than noted in R-CRC and L-CRC, and molecular heterogeneity among the histopathologic subtypes of appendiceal adenocarcinoma. Our findings may be critical to developing an individualized approach to appendiceal adenocarcinoma treatment.


Subject(s)
Adenocarcinoma/genetics , Appendiceal Neoplasms/genetics , Biomarkers, Tumor/genetics , Colorectal Neoplasms/genetics , Microsatellite Instability , Mutation , Adenocarcinoma/pathology , Adenocarcinoma, Mucinous/genetics , Adenocarcinoma, Mucinous/pathology , Appendiceal Neoplasms/pathology , Chromogranins/genetics , Colorectal Neoplasms/pathology , Female , GTP-Binding Protein alpha Subunits, Gs/genetics , Gene Expression Profiling , High-Throughput Nucleotide Sequencing/methods , Humans , Male , Proto-Oncogene Proteins p21(ras)/genetics , Pseudomyxoma Peritonei/genetics , Pseudomyxoma Peritonei/pathology , Retrospective Studies
11.
Immunotherapy ; 9(16): 1323-1330, 2017 12.
Article in English | MEDLINE | ID: mdl-29185395

ABSTRACT

AIM: To compare PD-L1 expression between metastatic uveal melanoma (MUM) and metastatic cutaneous melanoma (MCM). MATERIALS & METHODS: A total of 295 MCM and 78 MUM specimens were analyzed for tumor cell PD-L1 expression. Additionally, 91 MCM and 45 MUM specimens were analyzed for PD-1 expression on tumor-infiltrating lymphocytes. RESULTS: A total of 77/295 (26.1%) MCM specimens expressed PD-L1 as compared to 4/78 (5.1%) MUM specimens (p < 0.0001). PD-1 expression on tumor-infiltrating lymphocytes was greater in MCM (73.6%; 67/91) than in MUM (51.1%; 23/45), respectively (p = 0.009). CONCLUSION: Significant differences exist in PD-L1 expression between MCM and MUM. The lower PD-L1 expression in MUM may provide a rationale for failure of PD-1 inhibitor therapy and suggests that immune evasion in this disease may occur via alternative mechanisms.


Subject(s)
Antibodies, Monoclonal/therapeutic use , B7-H1 Antigen/immunology , Immunotherapy/methods , Lymphocytes, Tumor-Infiltrating/physiology , Melanoma/metabolism , Skin Neoplasms/metabolism , Uveal Neoplasms/metabolism , Diagnosis, Differential , Gene Expression Regulation , Humans , Melanoma/diagnosis , Melanoma/therapy , Neoplasm Metastasis , Prognosis , Skin Neoplasms/diagnosis , Skin Neoplasms/therapy , Treatment Outcome , Tumor Escape , Uveal Neoplasms/diagnosis , Uveal Neoplasms/therapy
12.
Transplantation ; 87(9): 1275-82, 2009 May 15.
Article in English | MEDLINE | ID: mdl-19424025

ABSTRACT

BACKGROUND: The use of nonautologous stem cells isolated from healthy donors for stem-cell therapy is an attractive approach, because the stem cells can be culture expanded in advance, thoroughly tested, and formulated into off-the-shelf medicine. However, human leukocyte antigen compatibility and related immunosuppressive protocols can compromise therapeutic efficacy and cause unwanted side effects. METHODS: Mesenchymal stem cells (MSCs) have been postulated to possess unique immune regulatory function. We explored the immunomodulatory property of human and porcine MSCs for the treatment of delta-sarcoglycan-deficient dystrophic hamster muscle without immunosuppression. Circulating and tissue markers of inflammation were analyzed. Muscle regeneration and stem-cell fate were characterized. RESULTS: Total white blood cell counts and leukocyte-distribution profiles were similar among the saline- and MSC-injected dystrophic hamsters 1 month posttreatment. Circulating levels of immunoglobulin A, vascular cell adhesion molecule-1, myeloperoxidase, and major cytokines involved in inflammatory response were not elevated by MSCs, nor were expression of the leukocyte common antigen CD45 and the cytokine transcriptional activator NF-kappaB in the injected muscle. Treated muscles exhibited increased cell-cycle activity and attenuated oxidative stress. Injected MSCs were found to be trapped in the musculature, contribute to both preexisting and new muscle fibers, and mediates capillary formation. CONCLUSIONS: Intramuscular injection of nonautologous MSCs can be safely used for the treatment of dystrophic muscle in immunocompetent hosts without inflaming the host immune system.


Subject(s)
Bone Marrow Cells/cytology , Mesenchymal Stem Cell Transplantation/methods , Muscle, Skeletal/physiopathology , Muscular Dystrophy, Animal/surgery , Transplantation, Heterologous/methods , Animals , Bone Marrow Transplantation , Cricetinae , Humans , Immunosuppressive Agents/therapeutic use , Injections, Intramuscular , Lipid Peroxidation , Male , Muscular Dystrophy, Animal/immunology , Regeneration , Reverse Transcriptase Polymerase Chain Reaction , Sarcoglycans/deficiency , Tissue Donors
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