Creation of Porous Fibers That Adsorb Pathogenic Substances of Intractable Diseases

Toray Industries, Inc. (Headquarters: Chuo-ku, Tokyo; President: Mitsuo Oya; hereinafter "Toray") has developed a technology to arbitrarily control the pore size of polymethyl methacrylate (PMMA) porous fibers in a wide range from several nm to about 1,000 nm (hereinafter, "this technology"), leading to the creation of porous fibers capable of selectively adsorbing pathogenic substances of intractable diseases. This technology contributes to proposing new blood purification treatment options that can replace or have a synergistic effect with conventional treatments for intractable diseases such as autoimmune diseases, cardiovascular metabolic diseases, neurodegenerative diseases, and cancer.

With the aging of the population and diversification of lifestyles, the number of patients with intractable diseases such as autoimmune diseases, cardiovascular metabolic diseases, neurodegenerative diseases, and cancer is increasing year by year. For these diseases, drug treatment and surgery are not always sufficiently effective, and there are cases where side effects or the risk of recurrence become an issue. Amidst this situation, there is a growing demand for technology that can efficiently remove high-molecular-weight pathogenic substances such as autoantibodies, lipoproteins, and exosomes from the blood.

PMMA is a material with good biocompatibility and moderate protein adsorption properties, and Toray is the only company in the industry to have commercialized PMMA porous fibers. Specifically, they are manufactured and sold as artificial kidneys and adsorption-type blood purifiers, with a track record of about 50 years in blood purification therapy applications.

By combining advanced analytical techniques such as small-angle X-ray scattering with digital technologies like phase separation simulation, Toray has analyzed the nano-level phase separation behavior during the spinning process of PMMA porous fibers in real time. This has led to the development of a pore size control technology that can control the pore diameter up to about 1,000 nm, which is about 50 times larger than the conventional ratio. Generally, increasing the pore size results in a sparse fiber structure and reduced strength, but this technology achieves both large pore size and strength. The application of this technology enables the selective adsorption and removal of high-molecular-weight pathogenic substances that could not be incorporated inside the pores conventionally.

In the future, for the treatment of intractable diseases such as autoimmune diseases, cardiovascular metabolic diseases, neurodegenerative diseases, and cancer, we will proceed with the design of pore sizes suitable for each disease and the development of mass production technology, aiming for early practical application. Furthermore, this technology can be expanded to applications other than medical devices; for example, we are promoting its expansion into biopharmaceutical manufacturing applications.

Toray will continue to embody its corporate philosophy, "Contributing to society through the creation of new value," by promoting the development of high-value-added products utilizing advanced material technologies, aiming for sustainable growth and expansion while contributing to society.

＜References＞

1) December 20, 2022 News Release
・Content: "Creation of Fibers that Highly Efficiently Adsorb Pathogenic Proteins in the Blood"

・Link: https://www.toray.co.jp/news/article.html?contentId=v7dxb7ht

2) November 10, 2023 News Release

・Content: "PMMA Porous Column that Highly Efficiently Adsorbs Pathogenic Proteins in the Blood Receives the '2023 Japanese Society for Artificial Organs Technology Award'"

・Link: https://www.toray.co.jp/news/article.html?contentId=hxpvupms