Japan’s Ministry of Health, Labour and Welfare (MHLW) has issued new notifications clarifying how pediatric drug development will be handled under amendments to the Pharmaceuticals and Medical Devices Act. These notifications will take effect on May 1, 2026.
The measures aim to strengthen incentives for pediatric research and development. One key update confirms that certain products undergoing pediatric development may receive an extended re-examination period. In Japan, new drugs are subject to a “re-examination period,” during which regulators review the product’s real-world safety and effectiveness after approval. During this time, competing companies cannot rely on the original clinical data to obtain approval for their similar products. This means that the period functions as a form of data protection for the innovator drug. When a drug is clearly recognized as requiring pediatric dosing, and the sponsor submits a pediatric development plan by the completion of the adult indication review, the protection period may be extended by an additional two years, up to a maximum of 12 years.
The MHLW also released revised guidance on how pediatric development plans should be prepared and reviewed. Under the amended framework, companies are expected to establish development plans for pediatric drug use during the course of adult drug development. To avoid delays in pediatric studies in Japan, the MHLW encourages participation in multi-regional clinical trials (MRCT) and recommends that sponsors consult early with the Pharmaceuticals and Medical Devices Agency (PMDA).
According to the updated guidance, the PMDA will review pediatric development plans, particularly when pediatric dosing needs to be determined or when a child-specific formulation is required. Companies are expected to use the formal PMDA pediatric development plan consultation to obtain early regulatory feedback.
Written by: Ames Gross – President and Founder, Pacific Bridge Medical (PBM)
Mr. Gross founded PBM in 1988 and has helped hundreds of medical companies with regulatory and business development issues in Asia. He is recognized nationally and internationally as a leader in the Asian medical markets. Mr. Gross has a BA degree, Phi Beta Kappa, from the University of Pennsylvania and an MBA from Columbia University.