Dec 10 (Reuters) - More than half of trial patients with an advanced, aggressive form of blood cancer lived for at least a year after one-time treatment with Yescarta, a novel therapy sold by Gilead Sciences Inc, according to study results presented on Sunday.
Yescarta, approved by the U.S. Food and Drug Administration in October for aggressive large B-cell lymphoma that did not respond to other treatments, is part of a new class known as chimeric antigen receptor T-cell therapies, or CAR-Ts, designed to reprogram the body's own immune cells to recognize and attack malignant cells.
Follow-up on 108 patients treated with Yescarta showed that 42 percent remained in remission after a median of 15 months, and 56 percent were still alive, according to research presented in Orlando at the annual meeting of the American Society of Hematology.
"This is an extremely valuable therapy for some patients who have no other options," said Dr Frederick Locke, vice chair of the department of blood and marrow transplant and cellular immunotherapy at Moffitt Cancer Center in Tampa, Florida and the trial's co-lead investigator.
He said patients who achieve remission after receiving Yescarta tend to stay in remission, but more work needs to be done to determine why some do not respond to the cell therapy.
After analyzing tumor tissue from before and after treatment in patients who relapsed, the researchers found that in a third of patients the CD19 protein targeted by Yescarta was no longer present on cancer cells. Also, more than two-thirds of tumors showed evidence of another protein, PDL1, likely helping the cancer cells survive.
Gilead is also studying Yescarta in combination with a PDL1 antibody, Roche Holding AG's Tecentriq, and results from an early-stage trial of that combination will be announced at ASH on Monday.
Gilead acquired Yescarta, which has a U.S. list price of $373,000, with its buyout earlier this year of Kite Pharmaceuticals.
(Reporting by Deena Beasley; Editing by Nick Zieminski)