Japanese researchers plan to launch a nation-wide clinical study on new cancer drugs for immunotherapy, including one marketed as "Opdivo".
The new drugs are used to treat certain kinds of cancer by boosting patients' immune systems.
Opdivo has been developed based on a study by a professor at Kyoto University, Tasuku Honjo. The Japanese immunologist won this year's Nobel Prize in Physiology or Medicine.
The new breed of cancer medicines has been proven to be highly effective. But some patients can suffer serious side effects.
The drugs cost more than 10 million yen, or over 89,000 dollars, a year per patient, impacting Japan's health insurance system.
More than 40 medical institutions across Japan, including the National Cancer Center, plan to jointly study optimal durations of treatment with the new drugs.
A research group that leads the study says that there are no clear rules on the length of treatment with immunotherapy drugs and doctors are expected to decide when to terminate it.
The study will involve 220 lung cancer patients for whom the new drugs have been proven to be effective after a one-year treatment.
The subjects will be divided into 2 groups. One will continue to take the drugs, and the other will discontinue treatment for a certain period to see if there are differences.
The researchers will then compare the two to determine an optimal duration for the drugs to work without causing serious side effects.
The group hopes that if dosing durations can be shortened, the medicines will cost less and side effects will be minimized.
The group says that the drugs will be given again to subjects who want to be back on the medication and to others for whom the drugs' effects were not long lasting.