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Update on Tozadenant Trial for Parkinson’s

On 11/20/17, Acorda Therapeutics, Inc. announced that it is discontinuing the tozadenant clinical trial.  They concluded that they could not be confident that weekly white blood cell count screening would sufficiently ensure patient safety.


On 11/15/17, Acorda Therapeutics, Inc. announced that several people living with Parkinson's who participated in the Phase III trial for tozadenant experienced agranulocytosis — a severe drop in the number of white blood cells which fight infection — leading to cases of sepsis and five fatalities. Participants in the trial will now have blood cell count monitoring increased from monthly to weekly.  The study has paused new enrollment in the long-term safety studies, pending further discussion with the independent Data Safety Monitoring Board (DSMB) and the United States Food and Drug Administration (FDA).

Tozadenant is an oral adenosine A2a receptor antagonist currently in Phase III development as an adjunctive treatment to levodopa in Parkinson’s disease patients to reduce OFF time.

Statement from the Parkinson’s Foundation

Our thoughts are with the family members who lost a loved one enrolled in this trial. Their participation in clinical research will ultimately help make life better for the people diagnosed with Parkinson's in the future. 

The Parkinson’s Foundation remains confident that Acorda and the FDA will investigate this rare event. Clinical trials in Parkinson’s disease — from oral therapies to surgical treatments — have had a strong safety record and they are critical in testing the safety and efficacy of investigational therapies.

In order to discover new PD therapies, we rely on brave and altruistic people, like the ones in this trial, to participate in clinical research. The Parkinson’s Foundation remains committed to supporting clinical research through our global network of Centers of Excellence and Parkinson’s Advocates in Research.

If you would like more information about the benefits and risks of clinical trial participation, learn more here.  If you have questions or concerns, please call our toll-free Helpline at 1-800-4PD-INFO (473-4636).

Thursday, November 16, 2017
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