DISCUSSION
In this study, we found 70.0% of all Japanese PHOs increasingly received the personal payments from pharmaceutical companies between 2016 and 2019. This study was the second study assessing board certificated specialists in Japan, only following Ozaki et al.8 Compared to their findings, the average payments to PHOs was only 0.15 times lower than that to the general hematologist-oncologists in Japan ($740 in PHO vs $4,383 in certificated general hematologist-oncologists per year).8 Considering that the number of pediatric cancer patients accounts for only about 0.2% of the total number of new cancer patients in Japan annually, it is reasonable that the average payment to PHOs is lower than that to general hematology-oncologists.
Meanwhile, we found that the average personal payments increased twofold in the four years. The increase in the average payment could be attributed to the fierce marketing competition for the new drugs for hemophilia. Specially, among the top five companies, while the total payments from Kyowa Kirin and Sumitomo Dainippon Pharma remained constant or decreased, the payments from Chugai, Takeda, and Bayer continuously increased through the four years. All the three companies had the novel drugs approved for hemophilia A during the four-years such as Emicizumab (HEMLIBRA approved in May 2018) from Chugai Pharmaceutical; rurioctocog alfa pegol (ADYNOVATE approved in December 2017) and rurioctocog alfa (ADVATE approved in August 2019) from Takeda Pharmaceutical; octocog alfa (KOVALTRY approved in March 2016) and damoctocog alfa pegol (JIVI approved in September 2018) from Bayer Yakuhin.
As described previously, the manual collection of payments from pharmaceutical companies may include human error and no inclusion of payments concerning meal, accommodation, travel, and education could lead to underreported payment value6-8, but in conclusion, majority of Japanese pediatric hematologists and oncologists received an increasingly large amounts of personal payments from pharmaceutical companies with novel drugs for congenital blood disorder for the reimbursement of lecturing, writing, and consulting between 2016 and 2019.