ABSTRACT
Fabry disease (FD) is an X-linked lysosomal storage disease. It is caused by deficiency of the enzyme α-galactosidase A (α-Gal A), which leads to excessive deposition of neutral glycosphingolipids, especially globotriaosylceramide (GL-3), in cells throughout the body. Progressive accumulation of GL-3 causes life-threatening complications in several tissues and organs, including the vasculature, heart, and kidney. Currently available enzyme replacement therapy for FD employs recombinant α-Gal A in two formulations, namely agalsidase alfa and agalsidase beta. Here, we evaluated JR-051 as a biosimilar to agalsidase beta in a non-clinical study. JR-051 was shown to have identical primary and similar higher-order structures to agalsidase beta. Mannose-6-phosphate content was higher in JR-051 than in agalsidase beta, which probably accounts for a slightly better uptake into fibroblasts in vitro. In spite of these differences in in vitro biological features, pharmacokinetic profiles of the two compounds in mice, rats, and monkeys were similar. The ability to reduce GL-3 accumulation in the kidney, heart, skin, liver, spleen, and plasma of Gla-knockout mice, a model of FD, was not different between JR-051 and agalsidase beta. Furthermore, we identified no safety concerns regarding JR-051 in a 13-week evaluation using cynomolgus monkeys. These findings indicate that JR-051 is similar to agalsidase beta in terms of physicochemical and biological properties.
Subject(s)
Biosimilar Pharmaceuticals/administration & dosage , Fabry Disease/drug therapy , Isoenzymes/administration & dosage , alpha-Galactosidase/genetics , Animals , Enzyme Replacement Therapy , Fabry Disease/genetics , Fabry Disease/pathology , Fibroblasts , Humans , Isoenzymes/genetics , Kidney/metabolism , Kidney/pathology , Liver/metabolism , Liver/pathology , Male , Mice , Mice, Knockout , Skin/metabolism , Skin/pathology , Spleen/metabolism , Spleen/pathology , Trihexosylceramides , alpha-Galactosidase/administration & dosageABSTRACT
One major concern with biosimilars is that small differences compared with reference products might lead to unforeseen immunogenicity, thus affecting patient safety and drug efficacy. Differences could be due to either post-translational modifications of the therapeutic protein and/or to traces of impurities from the manufacturing process. The results presented in this communication illustrate the efforts to assess "biosimilarity" of a biosimilar candidate to a reference product for a specific group of process-related impurities, the host cell proteins (HCP). Extensive characterization of HCP in the drug substance of a biosimilar candidate revealed the identity of HCP copurifying with the protein of interest and guided process development to improve overall HCP clearance in the downstream process. The data presented illustrate the challenge of matching the reference product on either quantitative or qualitative aspects of HCP impurities.
