Today, medicines produced domestically are readily available at pharmacies and supermarkets in Japan, but this was not the case in the past. One of the companies that significantly changed this situation was Arsemin Shokai, which later became Daiichi Pharmaceutical Co., Ltd., a predecessor of Daiichi Sankyo Co., Ltd. (Daiichi Sankyo).
Arsemin Shokai was founded to produce imported medicines domestically
In the 1900s, most medicines in Japan were imported from overseas. However, when the First World War broke out in the 1910s, they stopped reaching Japan and their prices dramatically went up. Therefore, the then Home Ministry began to produce medicines domestically, and private pharmaceutical companies were gradually established.
One of the medicines in short supply then was Salvarsan (trade name of arsphenamine), a treatment for syphilis launched in 1910 as a result of joint research by a German, Dr. Paul Ehrlich, and a Japanese, Dr. Sahachiro Hata. Sankyo Shoten (which later in 1913 became Sankyo Co., Ltd., a predecessor of Daiichi Sankyo ) began to import Salvarsan from Germany in 1912, but it was in short supply due to the spread of syphilis and subsequently its import was suspended due to the war.
Under such circumstances, Dr. Shozaemon Keimatsu of the South Manchuria Railway Central Research Laboratory (laboratory managed by the South Manchuria Railway in present-day Dalian, Liaoning Province, China) successfully test-produced Salvarsan and embarked on its commercialization. In June 1915, Dr. Keimatsu registered Salvarsan under the name of Arsemin and established the anonymous association Arsemin Shokai in Nihonbashi, Tokyo.
Succeeding in commercialization as a result of lengthy research by young researchers
However, the commercialization of Salvarsan was a long struggle. Arsemin was difficult to dissolve in water and only available for large-quantity intravenous injections, which were very painful. In order to solve this problem, research was conducted to make intramuscular injections possible, but they turned out to be less effective.
Therefore, three young researchers, including Junjiro Moriguchi, who engaged in studies of Salvarsan at the South Manchuria Railway Central Research Laboratory, were summoned to Japan to take charge of the research. The wooden one-story factory where they worked was sparsely equipped with distillers and lab tables, but after calling for workers and procuring equipment and raw materials for medicines, research began on December 1, 1915.
The researchers had to use large iron containers instead of the fine instruments they were accustomed to, handling raw materials of poor quality. For four months, up to March 1916, they continued to study from 8:00 a.m. until 2:00 or 3:00 a.m. at night. It was the cold season, but because some medicines had to be kept away from fire, they could not even warm themselves. Researcher Moriguchi wrote in his memoir that the snowy nights were harsh even on their young bodies, yet they were desperate to conduct their research.
Arsemin that could be used in small quantities was produced in late December 1915, the month the research began, but side effects were reported to be strong in animal tests and the research continued. Six months later, Researcher Bunji Ikeda of the South Manchuria Railway Central Research Laboratory became the first factory head in Japan to lead the creation of commercial products. In September 1916, Neo-Arsemin was finally completed. It had excellent results in animal and clinical trials and was proven effective. Upon its launch, it became popular among doctors for being more water-soluble and easier to handle than other products. Thus, the long, hard efforts by the doctors and researchers who strove for innovation to deliver high-quality medicines to the Japanese people more than bore fruit.