(CNN)Following two patient deaths last week and another earlier this year, Juno Therapeutics announced Thursday that it is putting its "ROCKET" trial on clinical hold, at the direction of the U.S. Food and Drug Administration. The patients enrolled in this Phase II trial are adults with relapsed or refractory B cell acute lymphoblastic leukemia, according to the biopharmaceutical company's website.
Fludarabine, Bishop explained, had shown to increase efficacy in previous studies, which is why the decision was made to add it to the pre-conditioning regimen in this particular trial. But an unforeseen interaction between fludarabine and the JCAR015 cells proved to be lethal.
Juno is petitioning to continue the trial with modifications, namely dropping fludarabine from pre-conditioning, in favor of a cyclophosphamide-only regimen. In turn, the FDA is asking Juno for revised protocols, consent forms and brochures, which Juno says it will submit this week.
The FDA monitors all U.S. drug trials. Fatal adverse events are "extremely rare."
See the latest news and share your comments with CNN Health on Facebook and Twitter.
"If at any time the FDA determines that human subjects are or would be exposed to an unreasonable and significant risk of illness or injury, the FDA may place the study on 'clinical hold,' which prohibits further investigation until the FDA's safety concerns are adequately addressed and the FDA removes the clinical hold order," FDA spokesperson Tara Goodin said in an email earlier this year
Read more: http://www.cnn.com/2016/07/08/health/cancer-immunotherapy-trial-deaths-juno-therapeutics/index.html