Acorda Therapeutics announced that it is discontinuing its clinical development program for tozadenant, an investigational treatment for Parkinson's disease, including immediately discontinuing dosing of all participants currently enrolled in its tozadenant studies.

The company made this decision based on new information obtained from the Phase 3 program related to previously disclosed agranulocytosis and associated serious adverse events. After analyzing this additional information, the company concluded that it could not be confident that weekly white blood cell count screening would sufficiently ensure patient safety. Acorda has informed regulatory authorities and trial investigators regarding the orderly closure of ongoing studies.

"Patient safety is our top priority," said Ron Cohen, M.D., Acorda's President and CEO. "While we are deeply disappointed by this outcome, we remain committed to the Parkinson's community, which is in great need of new therapeutic options. We are grateful to the patients who volunteered for the tozadenant studies and to their care partners, clinical investigators, and the internal and external study teams." Over 90% of the participants in the placebo-controlled Phase 3 efficacy and safety study, CL-05, have completed the study.

The company expects data from these participants in the first quarter of 2018 and to present these at appropriate medical/scientific venues.