A doxycycline-inducible CYP3A4-Caco-2 cell line as a model for evaluating safety of aflatoxin B1 in the human intestine.

Exposure of humans to aflatoxin B1 (AFB1) via ingestion of contaminated agricultural products is a major concern for human health throughout the world because epoxidized AFB1, biotransformed from AFB1 by hepatic CYP3A4, is strongly hepatotoxic and hepatocarcinogenic. Intestinal epithelial cells serve as a physical and physiological barrier against xenobiotics via their intercellular tight junction (TJ) seals and the metabolizing enzyme CYP3A4. However, the effect of AFB1 on the intestinal barrier remains unclear. Here, we investigated the influence of AFB1 on these physical and physiological intestinal barriers by means of an in vitro human intestinal model utilizing doxycycline-inducible CYP3A4-expressing Caco-2 cells, in which CYP3A4 activity is comparable to that in the adult human intestine. Cellular toxicity of AFB1 in induced Caco-2 cells (i.e., cells in which expression of CYP3A4 is induced by doxycycline) was approximately 5 times that of uninduced Caco-2 cells. Exposure to 16 µM AFB1 did not decrease the transepithelial electric resistance (TEER; a measure of TJ barrier integrity) in monolayers of uninduced Caco-2 cells to 95.8 % of that in vehicle-treated cells; in contrast, in induced Caco-2 cells, TEER was reduced to 28.8 %. Exposure to 16 µM AFB1 increased paracellular permeation of 4- and 20-kDa dextrans (paracellular permeation markers) through monolayers of induced Caco-2 cells to 5.4 and 5.2 times that through uninduced Caco-2 cells. These results together show that ingested AFB1 can modulate the intestinal barrier, and that inducible CYP3A4-expressing Caco-2 cells are a promising tool for evaluating the safety of food contaminants in the human intestine.

Overview of the Premarketing and Postmarketing Requirements for Drugs Granted Japanese Conditional Marketing Approval.

For drugs that are intended to fill unmet medical needs, such as the treatment of rare diseases or a subtype of cancer, it can take a long time to conduct confirmatory clinical trials due to limited patient availability. Delayed access to these drugs increases the risk of mortality of patients with these diseases. To address this issue, the Ministry of Health, Labour, and Welfare of Japan has decided to implement the Conditional Early Approval System with issuing the Ministry Notification in 2017. Drugs eligible for conditional early approval are those that are indicated for the treatment of a serious disease, have proven safety and efficacy, and cannot be examined easily by confirmatory clinical trials. When the benefit of immediate availability outweighs the risk of having less comprehensive data with which to confirm the clinical benefit of a product in the premarketing phase, products can be approved under the Conditional Early Approval System, accompanied by postmarketing regulatory requirements to manage postmarketing risks and, if needed, conduct postmarketing confirmatory clinical studies. Overview of the pre-approval and post-approval regulatory considerations will promote to more efficiently develop pharmaceutical products that fill unmet medical needs, leading to the prompt delivery of safe and effective drugs to patients who often have few therapeutic options available. As of March 2020, four drugs had been approved under the Conditional Early Approval System. In this review, we describe the premarketing and postmarketing requirements of these drugs and discuss the regulatory landscape around the Conditional Early Approval System.

The Roadmap to Approval under Japan's Two-Track Regulatory System: Comparing Six Regenerative Medical Products.

The Japanese conditional and time-limited (CTL) approval framework, a tiered system for regenerative medical products, was initiated in 2014. Here, we compare the dossiers of six regenerative medical products with either direct full approval or CTL approval, and we discuss the regulatory considerations for obtaining approval under the CTL approval framework.

New Japanese Regulatory Frameworks for Post-Marketing Management of Pharmaceutical Products.

Dossiers on approved pharmaceutical products must be kept updated and current during the products' life cycles. The coalition, merger and acquisition along with corporate strategy that pursues efficiency and profitability of pharmaceutical companies have led to the globalization of supply chains for pharmaceutical ingredients and instruments in the post-marketing phase, and progress in manufacturing technologies can improve manufacturing processes during this phase. Regulatory requirements for post-marketing management of pharmaceutical products sometimes differ among countries around the world depending on national/regional policies or situations, even though the basic concepts of each regulation are the same. Therefore, an understanding of up-to-date region specific regulatory management frameworks is important for the optimal provision of pharmaceutical products by pharmaceutical industries. The amendment of the Japanese Pharmaceutical and Medical Device Act (Act No. 63 of 2019) was promulgated in December 2019, and will be enforced from September 2020 onwards. The amended Act sets out regulatory frameworks for post-marketing management systems, including inspection for good manufacturing practice of drugs, quasi-drugs, and gene-, cell-, and tissue-based products; and post-approval change-management protocols. Here, we review these new Japanese post-marketing management frameworks.

A Concept for a Japanese Regulatory Framework for Emerging Medical Devices with Frequently Modified Behavior.

Recent progress in the Internet of Things and artificial intelligence has made it possible to utilize the vast quantity of personal health records, clinical data, and scientific findings for prognosis, diagnosis, and therapy. These innovative technologies provide new possibilities with the development of medical devices (MDs), whose behaviors can be continuously modified. A novel regulatory framework covering these MDs is now under discussion in Japan. In this review, we introduce the regulatory initiative for MDs and the importance of a paradigm shift from regulation to innovation regarding MDs.

Regulatory perspectives of Japan.

In this article, the 2013 regenerative medicine laws and regulations in Japan are addressed. The Regenerative Medicine Promotion Law was promulgated in May 2013 to promote comprehensive measures from research and development to practical use of regenerative medicines. In line with this purpose, two acts have been passed by the National Diet in November 2013. One is the Act on the Safety of Regenerative Medicine, which classifies regenerative medicines based on risk. Additionally this Act stipulates the procedures for offering regenerative medicines, the measures for appropriate provision of the regenerative medicines, and authorization to manufacture designated cellular therapeutic products for therapeutic use. The other is the Act on Pharmaceuticals and Medical Devices, previously named the Pharmaceutical Affairs Act, which establishes regulations tailored to the characteristics of regenerative medicinal products, including an expedited approval system.