UPDATE 1-Novartis approval for gene therapy signals new cancer treatment era

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Aug 30 (Reuters) - The U.S. Food and Drug Administration (FDA) on Wednesday gave a green light to Novartis AG's leukemia treatment, marking the first time that a highly anticipated new type of potent gene-modifying immunotherapy has gained approval in the United States.

The treatment, to be sold under the name Kymriah, was approved for patients up to 25 years of age who have relapsed or were not helped by initial treatment for B-cell acute lymphoblastic leukemia.

Kymriah belongs to a new class of drugs called chimeric antigen receptor T-cell, or CAR-T therapies, that involves removing disease-fighting T cells from a patient, genetically modifying them to better recognize and fight cancer and then replacing them, where they can circulate for years seeking out the disease.

"Were entering a new frontier in medical innovation with the ability to reprogram a patients own cells to attack a deadly cancer, FDA Commissioner Scott Gottlieb said in a statement.

U.S. biotech Gilead Sciences jumped into the field this week with its announcement of a nearly $12 billion deal to buy Kite Pharma. Gilead shares jumped 5.5 percent on Wednesday as Kite is widely seen as likely to receive the next U.S. approval of a CAR-T therapy.

Novartis has not yet announced the cost for the therapy, but British health authorities have said a price of $649,000 for a one-time treatment would be justified given the significant benefits, according to a Kaiser Health News report last week. (Reporting by Bill Berkrot in New York and Reporting by Natalie Grover and Akankshita Mukhopadhyay in Bengaluru; Editing by Shounak Dasgupta and Matthew Lewis)