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Statement on the Termination of QE3 Study


On May 27, 2011, the NINDS stopped the QE3 Phase III study of Coenzyme Q10 for treatment of early stage Parkinson's disease, acting on the recommendation of the study's Data Safety Monitoring Board (DSMB). During the most recent DSMB review, the results of an interim analysis showed that it was futile to complete the study because longer patient follow-up was not likely to demonstrate a statistically significant difference between active treatment and placebo. To date, the investigators have not found any safety concerns related to Coenzyme Q10 at dosages of 1200mg/day and 2400mg/day for up to 16 months of treatment. Site investigators and coordinators have informed participants of the study's closure and have encouraged each participant to schedule a final study visit.

The QE3 study, administered by the Parkinson Study Group, enrolled 600 patients with early Parkinson's disease at 67 sites throughout North America. Participants were randomized to receive one of the two dosing levels of active CoQ10 or matching placebo. All subjects also received vitamin E at a dosage of 1200 IU/day. CoQ10 is an antioxidant which has an important role in mitochondrial function. Oxidative stress and mitochondrial dysfunction have both been implicated as contributors to Parkinson's disease.

The principal investigators are in the process of conducting a detailed analysis of the complete data set from the QE3 study and plan to publish these results in a scientific journal in an expedited manner.

"We are greatly indebted to the study participants and to the investigators for their time and dedication to this study. Although we had hoped the results would be more promising, the study answers the important question of whether CoQ10 can delay the progression of Parkinson's disease. The QE3 study was conducted with the utmost efficiency and thoroughness and has provided a valuable contribution to Parkinson's disease research and to the Parkinson's community," said Walter Koroshetz, M.D., Deputy Director of NINDS.

Last updated June 2, 2011