Eisai Co. CEO Haruo Naito said Wednesday that a new drug for Alzheimer's disease it has developed with U.S. firm Biogen Inc. has the potential to become a "blockbuster" product.

The approval by the U.S. Food and Drug Administration on Monday of the drug Aduhelm raised hopes for the treatment of Alzheimer's disease. But concern remains about higher U.S. medical costs as a patient would be charged $56,000 a year.