Publications by authors named "Paul Grimsey"

Tominersen is an intrathecally administered antisense oligonucleotide targeting huntingtin mRNA which leads to a dose-dependent, reversible lowering of cerebrospinal fluid (CSF) mutant huntingtin protein concentration in individuals with Huntington's disease. Nonlinear mixed-effect population pharmacokinetic (PopPK) modeling was conducted to characterize the CSF and plasma pharmacokinetics (PK) of tominersen, and to identify and quantify the covariates that affect tominersen PKs. A total of 750 participants from five clinical studies with a dose range from 10 to 120 mg contributed CSF (n = 6302) and plasma (n = 5454) PK samples.

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Background And Objective: Spinal muscular atrophy (SMA) is a progressive neuromuscular disease caused by insufficient levels of survival motor neuron (SMN) protein. Risdiplam (Evrysdi) increases SMN protein and is approved for the treatment of SMA. Risdiplam has high oral bioavailability and is primarily eliminated through hepatic metabolism by flavin-containing monooxygenase3 (FMO3) and cytochrome P450 (CYP) 3A, by 75% and 20%, respectively.

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Risdiplam (Evrysdi) improves motor neuron function in patients with spinal muscular atrophy (SMA) and has been approved for the treatment of patients ≥2 months old. Risdiplam exhibits time-dependent inhibition of cytochrome P450 (CYP) 3A in vitro. While many pediatric patients receive risdiplam, a drug-drug interaction (DDI) study in pediatric patients with SMA was not feasible.

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Rationale: The RECIST guideline defines four categories of response to treatment for cancer patients according to post-baseline changes in tumor burden, hence ignoring disease history. However, if left untreated, tumors grow exponentially, implying that pretreatment changes in tumor size are key to thoroughly assess efficacy. We present a model-based approach to estimate the rates of changes in tumor mass, before and after treatment onset.

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A mechanistic population-pharmacokinetic model was developed to predict oseltamivir exposures in neonates and infants accounting for physiological changes during the first 2 years of life. The model included data from 13 studies, comprising 436 subjects with normal renal function (317 pediatric subjects (≥ 38 weeks postmenstrual age (PMA), ≥ 13 days old) and 119 adult subjects < 40 years). Concentration-time profiles of oseltamivir and its active metabolite, oseltamivir carboxylate (OC), were characterized by a four-compartment model, with absorption described by three additional compartments.

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Objectives: To investigate the pharmacokinetics, pharmacodynamics, safety and efficacy of subcutaneous tocilizumab 162 mg weekly (QW) or every other week (Q2W) in rheumatoid arthritis patients on methotrexate.

Methods: This was a multicenter, open-label, randomized, parallel group study. Patients were randomly assigned to receive tocilizumab 162 mg subcutaneously QW or Q2W for 12 weeks.

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