Optimal Anti-cancer Drug Profiles for Effective Penetration of the Anti-cancer Drug Market by Generic Drugs in Japan.

Background: The increased use of generic drugs is a good indicator of the need to reduce the increasing costs of prescription drugs. Since there are more expensive drugs compared with other therapeutic areas, "oncology" is an important one for generic drugs. The primary objective of this article was to quantify the extent to which generic drugs in Japan occupy each level of the Anatomical Therapeutic Chemical (ATC) classification system.

Methods: The dataset used in this study was created from publicly available information obtained from the IMS Japan Pharmaceutical Market database. Data on the total amount of sales and number of prescriptions for anti-cancer drugs between 2010 and 2016 in Japan were selected. The data were categorized according to the third level of the ATC classification system.

Results: All categories of the ATC classification system had increased market shares in Japan between 2010 and 2016. The barriers to market entry were relatively low in L01F (platinum anti-neoplastics), L01C (plant-based neoplastics), L02B (cytostatic hormone antagonists), and L01D (anti-neoplastic antibiotics) but were high in L02A (cytostatic hormones), L01H (protein kinase inhibitors), and L01B (anti-metabolites).

Conclusions: Generic cancer drugs could bring savings to Japanese health care systems. Therefore, their development should be directed toward niche markets, such as L02A, L01H, and L01B, and not competitive markets.