Publications by authors named "Vaddady P"

Article Synopsis
  • This study evaluated the pharmacokinetics (PK) of quizartinib and its metabolite AC886 in newly diagnosed FLT3-ITD-positive acute myeloid leukemia (AML) patients receiving standard chemotherapy, using data from the Phase 3 QuANTUM-First trial and earlier studies.
  • The PK of quizartinib was modeled as a three-compartment system, while AC886 followed a two-compartment model, both showing significant variability among individuals.
  • The research also identified the influence of CYP3A inhibitors on drug exposure, revealing a need for dose adjustments and noting differences in quizartinib exposure across treatment phases compared to previously studied patient groups.
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Article Synopsis
  • Quizartinib extends the QT interval by inhibiting a specific potassium current, and its effects were studied in newly diagnosed acute myeloid leukemia (AML) patients using complex modeling techniques during a clinical trial.
  • The research evaluated how quizartinib and its metabolite AC886 impact the Fridericia-corrected QT interval (QTcF) using multiple measurements and various modeling approaches, identifying factors like age and hypokalaemia as relevant.
  • Results showed a significant non-linear increase in QTcF with higher quizartinib doses, supporting the need for dosage adjustments in patients, especially when combined with certain other medications.
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Stan is a powerful probabilistic programming language designed mainly for Bayesian data analysis. Torsten is a collection of Stan functions that handles the events (e.g.

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Article Synopsis
  • The landscape of oncology drug development has improved significantly, leading to better patient outcomes and quality of life, particularly through initiatives like Project Optimus by the FDA.
  • Project Optimus aims to reform how drug doses are selected in oncology, shifting the focus from maximum tolerated doses to more personalized strategies that consider disease and patient specifics.
  • The Oncology Dose Optimization IQ Working Group emphasizes the need for a tailored, evidence-based approach to dose optimization, acknowledging industry's challenges and advocating for strategies that adapt to various factors in cancer treatment.
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To replace the conventional maximum tolerated dose (MTD) approach, a paradigm for dose optimization and dose selection that relies on model-informed drug development (MIDD) approaches has been proposed in oncology. Here, we report our application of an MIDD approach during phase I to inform dose selection for the late-stage development of datopotamab deruxtecan (Dato-DXd). Dato-DXd is a TROP2-directed antibody-drug conjugate being developed for advanced/metastatic non-small cell lung cancer (NSCLC) and other tumors.

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Recent breakthroughs in artificial intelligence (AI) and machine learning (ML) have ushered in a new era of possibilities across various scientific domains. One area where these advancements hold significant promise is model-informed drug discovery and development (MID3). To foster a wider adoption and acceptance of these advanced algorithms, the Innovation and Quality (IQ) Consortium initiated the AI/ML working group in 2021 with the aim of promoting their acceptance among the broader scientific community as well as by regulatory agencies.

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Imipenem/cilastatin/relebactam is approved for the treatment of serious gram-negative bacterial infections in adults. This study assessed the pharmacokinetics (PK), safety, and tolerability of a single dose of imipenem/cilastatin/relebactam (with a fixed 2:1 ratio of imipenem/cilastatin to relebactam, and with a maximum dose of 15 mg/kg imipenem and 15 mg/kg cilastatin [≤500 mg imipenem and ≤500 mg cilastatin] and 7.5 mg/kg relebactam [≤250 mg relebactam]) in children with confirmed/suspected gram-negative bacterial infections receiving standard-of-care antibacterial therapy.

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Insulin molecules of size much greater than natural insulin have been synthesized and studied with the intention of widening the therapeutic window between adequate glycemic control and hypoglycemia as compared with conventional insulins. MK-1092 is a synthetic insulin dimer with favorable properties demonstrated in preclinical studies. Here, we report the results of the first-in-human, randomized, double-blind, active-control, single ascending dose trial of MK-1092, conducted in healthy adults, adults with type 1 diabetes (T1D), and adults with type 2 diabetes (T2D).

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For pharmacokinetics characterization of a therapeutic insulin dimer, an ultrasensitive plasma method was required due to the expected low circulating levels in humans. A bioanalytical strategy combining immunoprecipitation enrichment with liquid chromatography - tandem mass spectrometry (LC-MS/MS) analysis of the intact protein offers the opportunity to resolve the analyte from endogenous and exogenous insulin and insulin analogs. Nonetheless, interference from complex background matrix was observed limiting reliable measurements at the low concentration range.

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ModVizPop is an interactive and dynamic visualization tool developed for simulating differential equation-based population pharmacokinetic (PK) and pharmacodynamic (PD) models with variability. It has a built-in PK/PD ordinary differential equations library of models to choose from alongside the ability to plug in a user-defined model from a local or project directory. The user interface consists of several key inputs for performing the simulations as well as options to visualize the plots, perform simple noncompartmental analysis, and review inputs and model code.

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Doravirine is a non-nucleoside reverse transcriptase inhibitor for treatment of human immunodeficiency virus type 1 (HIV-1) infection. A population pharmacokinetic (PK) model for treatment-naive participants in doravirine clinical studies was updated with data from switch participants in the DRIVE-SHIFT trial and used to estimate individual PK parameter values and evaluate the efficacy exposure-response relationship. The results support the 100-mg dose for people living with HIV switching to a doravirine-based regimen (This study has been registered at ClinicalTrials.

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Doravirine is a non-nucleoside reverse transcriptase inhibitor approved for the treatment of HIV-1. In a phase 1 trial, doravirine exposure was transiently decreased when treatment was started immediately after stopping efavirenz. In a post-hoc subgroup analysis of participants who switched from an efavirenz-based regimen to doravirine/lamivudine/tenofovir disoproxil fumarate in the phase 3 DRIVE-SHIFT trial, doravirine plasma levels at week 4 were similar to non-induced levels, and HIV-1 suppression was maintained at weeks 24 and 48.

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Spectinamides are a novel class of antibiotics under development for the treatment of MDR- and XDR-tuberculosis, with 1599 and 1445 as early lead candidates within this group. In order to evaluate and differentiate the pharmacological properties of these compounds and assist in candidate selection and design of optimal dosing regimens in animal models of Mtb infection, time kill curve assessments were performed in a previously established in vitro PK/PD model system. The performed studies and subsequent pharmacometric analysis indicate that the anti-mycobacterial activity of 1599 exhibits concentration-dependent killing whereas 1445 shows time-dependent killing.

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We conducted two phase I trials to evaluate the pharmacokinetic interactions between elbasvir (EBR), grazoprevir (GZR), and methadone (MK-8742-P010 and MK-5172-P030) in non-hepatitis C virus (HCV)-infected participants on methadone maintenance therapy. Coadministration of EBR or GZR with methadone had no clinically meaningful effect on EBR, GZR, or methadone pharmacokinetics. The geometric mean ratios (GMRs) for R- and S-methadone AUC were 1.

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The aims of these phase I trials were to evaluate the pharmacokinetic interaction between elbasvir (EBR) or grazoprevir (GZR) and buprenorphine/naloxone (BUP/NAL). Trial 1 was a single-dose trial in healthy participants. Trial 2 was a multiple-dose trial in participants on BUP/NAL maintenance therapy.

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GPR40 mediates free fatty acid-induced insulin secretion in beta cells. We investigated the safety, pharmacokinetics, and glucose response of MK-8666, a partial GPR40 agonist, after once-daily multiple dosing in type 2 diabetes patients. This double-blind, multisite, parallel-group study randomized 63 patients (placebo, n = 18; 50 mg, n = 9; 150 mg, n = 18; 500 mg, n = 18) for 14-day treatment.

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Use of agents to suppress gastric acid secretion is common among patients with hepatitis C virus (HCV) infection. The aims of this open-label, three-period, fixed-sequence study were to evaluate the effect of famotidine and pantoprazole on the pharmacokinetics and safety of elbasvir/grazoprevir fixed-dose combination (FDC) in 16 healthy subjects. Elbasvir and grazoprevir each exhibited similar pharmacokinetics following single-dose administration of elbasvir/grazoprevir with or without famotidine or pantoprazole.

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Although the classical antibiotic spectinomycin is a potent bacterial protein synthesis inhibitor, poor antimycobacterial activity limits its clinical application for treating tuberculosis. Using structure-based design, we generated a new semisynthetic series of spectinomycin analogs with selective ribosomal inhibition and excellent narrow-spectrum antitubercular activity. In multiple murine infection models, these spectinamides were well tolerated, significantly reduced lung mycobacterial burden and increased survival.

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For rapid anti-tuberculosis (TB) drug development in vitro pharmacokinetic/pharmacodynamic (PK/PD) models are useful in evaluating the direct interaction between the drug and the bacteria, thereby guiding the selection of candidate compounds and the optimization of their dosing regimens. Utilizing in vivo drug-clearance profiles from animal and/or human studies and simulating them in an in vitro PK/PD model allows the in-depth characterization of antibiotic activity of new and existing antibacterials by generating time–kill data. These data capture the dynamic interplay between mycobacterial growth and changing drug concentration as encountered during prolonged drug therapy.

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Hemorrhagic shock involves loss of a substantial portion of circulating blood volume leading to diminished cardiac output and oxygen delivery to peripheral tissues. In situations where an immediate resuscitation cannot be provided, pharmacotherapy with a novel combination of Δ9-tetrahydro-cannabinol (THC) and celecoxib (CEL) is currently investigated as an alternative strategy to prevent organ damage. In the present study, 28 Yorkshire×Landrace pigs were used to study the pharmacokinetics of THC and CEL in an established porcine model of hemorrhagic shock.

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A series of 2-aryl-4-benzoyl-imidazoles (ABI) was synthesized as a result of structural modifications based on the previous set of 2-aryl-imidazole-4-carboxylic amide (AICA) derivatives and 4-substituted methoxylbenzoyl-aryl-thiazoles (SMART). The average IC(50) of the most active compound (5da) was 15.7 nM.

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