Felix J Tsai, Marcus Jaeger, Teresa Coelho, Evan T Powers, Jeffery W Kelly
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引用次数: 0
Abstract
Background: Hereditary transthyretin (TTR) amyloidosis (ATTRv) initially presents as a polyneuropathy and/or a cardiomyopathy. Central nervous system (CNS) pathology in ATTRv amyloidosis, including focal neurological episodes, dementia, cerebrovascular bleeding, and seizures, appears around a decade later. Wild-type (WT) TTR amyloidosis (ATTRwt) causes a cardiomyopathy. CNS pathology risk likely also increases in these patients as cardiomyopathy progresses. Herein, we study tafamidis-mediated TTR kinetic stabilisation in cerebrospinal fluid (CSF).
Methods: Varying tafamidis concentrations (50-1000 nM) were added to CSF from healthy donors or ATTRv patients, and TTR stabilisation was measured via the decrease in dissociation rate.
Results: Tafamidis meglumine (Vyndaqel) can be dosed at 20 or 80 mg QD. The latter dose is bioequivalent to a 61 mg QD dose of tafamidis free acid (Vyndamax). The tafamidis CSF concentration in ATTRv patients on 20 mg Vyndaqel is ∼125 nM. By linear extrapolation, we expect a CSF concentration of ∼500 nM at the higher dose. When tafamidis is added to healthy donor CSF at 125 or 500 nM, the WT TTR dissociation rate decreases by 42% or 87%, respectively.
Conclusions: Tafamidis stabilises TTR in CSF to what is likely a clinically meaningful extent at CSF concentrations achieved by the normal tafamidis dosing regimen.
期刊介绍:
Amyloid: the Journal of Protein Folding Disorders is dedicated to the study of all aspects of the protein groups and associated disorders that are classified as the amyloidoses as well as other disorders associated with abnormal protein folding. The journals major focus points are:
etiology,
pathogenesis,
histopathology,
chemical structure,
nature of fibrillogenesis;
whilst also publishing papers on the basic and chemical genetic aspects of many of these disorders.
Amyloid is recognised as one of the leading publications on amyloid protein classifications and the associated disorders, as well as clinical studies on all aspects of amyloid related neurodegenerative diseases and major clinical studies on inherited amyloidosis, especially those related to transthyretin. The Journal also publishes book reviews, meeting reports, editorials, thesis abstracts, review articles and symposia in the various areas listed above.