Gilead Sciences Inc.’s $11 billion bet on buying Kite Pharma Inc. is poised to pay off, with the approval Wednesday of Kite’s flagship cell-therapy treatment for adults with advanced lymphoma.

The therapy, known as a Car-T treatment, uses genetically engineered T-cells to attack the blood cancer. It is the second such therapy to get a regulatory green light, after Novartis AG’s Car-T drug Kymriah was approved in late August for a form of leukemia in children and young adults.

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