TOKYO – Japan's Ono Pharmaceutical Co. Ltd. recently got into a public debate at home about the price of its cancer drug, Opdivo (nivolumab), which critics argue could bring too great a burden on the national welfare system. The company, however, said an analyst's estimates as to the amount of people that will use the anti-PD-1 drug and the length of time for which they will use it are both exaggerated.