TOKYO, May 15 (Xinhua) -- A panel from Japan's health and welfare ministry on Wednesday approved a new cancer treatment to be covered by national health insurance, in a move marking the most expensive treatment to be covered by public health insurance.

The price of the new drug therapy to treat leukemia and other forms of blood cancers, marketed by Swiss pharmaceutical firm Novartis and called Kymriah, has been set at 33.49 million yen (305,000 U.S. dollars), the panel said.

The cost of the drug will be a record high for any single drug currently available through doctors and hospitals in Japan and coverage by national health insurance will begin from May 22, the panel decided.

The drug was first approved for use in Japan in March and will be the country's first cancer treatment involving CAR-T cell therapy, which works by genetically modifying a patient's own immune system T-cells to boost their ability to fight the disease.

The drug that has already been approved in the United States and Europe and in clinical trials in Japan was effective in improving the symptoms of patients suffering from leukemia and lymphoma.

The health ministry estimates that more than 200 patients a year will be eligible to use the drug, although eligible patients seeking national health insurance coverage must be aged 25 or under and seen no effective results from current standard treatments.

The ministry said the new therapy will accrue some 7.2 billion yen (65.78 million U.S. dollars) in revenue per year, under its system of covering between 70 and 90 percent of national health insurance policyholders' medical expenses, depending on their financial circumstances.

Some critics of the move have said, however, that the government footing such a large bill for the expensive treatment is not conducive to tacking the nation's already hefty burden of financing ever-increasing medical and social welfare costs connected to Japan's rapidly aging society.