The big news right now in the medical world is the development of anti-cancer drugs that use the body's natural immune system to fight off tumors. In Japan, the most famous of these drugs is probably Opdivo, created by the relatively minor Ono Pharmaceutical Co. in collaboration with Bristol-Myers Squibb Co.

Last summer, Opdivo was approved for treating a certain type of lung cancer by the Ministry of Health, Labor and Welfare, which means national health insurance will pay for treatments. That's very important, since the drug costs a staggering ¥1.33 million per dose.

Under normal conditions of care for a lung cancer patient weighing 60 kilograms, the cost of using Opdivo would come to ¥2.55 million a month. However, an insured individual would only pay about ¥650,000 a year thanks to a special exception for "high-priced medicines" that reduces a patient's payment depending on their income. And if the patient is over 70 years old, the amount comes down even further, since the elderly only have to pay 10 percent of their medical costs out of pocket to begin with, rather than the 30 percent that most people pay through national health insurance.