Current trends and challenges in pediatric cancer drug development in Japan

<p>Cancer remains a leading cause of death in children. A “drug lag” with regard to the introduction of standard therapeutic drugs into the Japanese market has been a long-standing concern, particularly with regard to pediatric solid tumors. Legislation to promote pediatric drug development has been enforced in the United States since 2003, and the “Research to Accelerate Cures and Equity for Children Act” was legislated in 2017. This Act mandates that pharmaceutical companies test agents used for treatment of adult cancers as anticancer agents in children in cases in which a shared molecular target is observed. Since 2017, development of molecular targeted drugs for pediatric cancer has been accelerated in the United States, which has led to a subsequent increase in the lag in Japan, following partial improvement observed previously with regard to therapy of hematological malignancies. The slow progress of pediatric cancer drug development in Japan is attributable to (a) small market size but high burden of development costs and legal obligations (for example, stable drug supply, safety monitoring) for companies, (b) shortage of experienced institutions and human resources for pediatric trials, (c) difficulties in acquisition of research funds owing to limited public budget allocation for investigator-initiated pediatric drug development, and (d) difficulties in recruitment of patients in trials considering rarity of diseases in this patient population. The existing system is inefficient in promoting pediatric cancer drug development, and a major reform of the model is warranted. Additionally, it is important to establish strategies to facilitate access to these drugs before they are approved for children diagnosed with cancer.</p>