Acorda shares plunge on Parkinson's drug trial setback

Acorda Therapeutics (Nasdaq: ACOR) yesterday announced that it has increased the frequency of blood cell count monitoring for participants to weekly in its Phase III program of tozadenant for Parkinson’s disease.

The company, whose share plunged by 40% to $17.05 on the news yesterday, has also paused new enrollment in the long-term safety studies, pending further discussion with the independent Data Safety Monitoring Board (DSMB) and the US Food and Drug Administration.

Acorda said it took this action in response to cases of agranulocytosis, possibly drug-related, and in some cases associated with sepsis and death. Agranulocytosis is the absence of white blood cells, which fight infection.