Methotrexate for the treatment of juvenile idiopathic arthritis: process to approval for JIA indication in Japan

Proposal for the development of biologics in pediatric rheumatology

In order to assess the development, approval and early introduction into clinical practice of biologics in the pediatric field, we herein describe the current status of the development to approval of biologics as anti-rheumatic agents for children in Japan, discuss the present problems and provide a proposal for the future. It has become apparent that the duration of the review period required for the preparation of clinical trials and Pharmaceuticals and Medical Devices Agency approval is clearly reduced compared with the past. Thus, it was speculated that a rate-limiting step in the process from development to approval was the duration of clinical trials from start to end. Hence, we focused on the following key words with regard to promotion of the development of biologics and their early practical use: "registry", "centralization", and "global cooperation", all of which are related to the reduction of duration of a clinical trial. In conclusion, to reduce the duration of a clinical trial, it is essential to complete a world-scale registry system by developing the registry system established by the Pediatric Rheumatology Association of Japan. The next step is then to carefully plan to participate in the international network using the world-scale registry system, and develop global cooperative trials in which we can ensure a sufficient number of entries from Japan.

Dosing regimen determination for juvenile idiopathic arthritis: a review of studies during drug development

Juvenile idiopathic arthritis (JIA) is the most common childhood arthritis. In the past 10-15 years, the medical treatment options of JIA have greatly evolved and expanded due to a better understanding of the disease and the application of biologic agents. Regulations pertinent to pediatric clinical research have also helped provide a legal basis for investigating the effects of drugs and biologics in pediatrics and facilitate the pediatric drug development. The evaluation of clinical pharmacology, efficacy, and safety has provided valuable labeling information for pediatric use, including comparing exposure between adult and pediatric patients, bridging different formulations and regimens, providing appropriate dose selection recommendation with the modeling and simulation approach, and assessing the risks and benefits. This review summarizes the drugs and biologics with JIA labeling implications and discusses the application of clinical pharmacology, safety, and efficacy assessment in determining pediatric dosing regimens.