Recruiting has begun for 2CARE, a large PHASE 3 trial testing Coenzyme Q-10 in Huntington's disease. At its conclusion we will hopefully learn a definitive answer whether high doses of this supplement can slow the progression of Huntington's. The Huntington Study Group is recruiting for more than 600 participants for this trial that is slated to last as long as five years, but will be stopped earlier if benefit is shown during a shorter time.

On a less positive front, several recent trials of Coenzyme Q-10 for Parkinson's have not confirmed the benefit that an earlier trial had suggested . .

Coenzyme Q-10 in Parkinson's: Remember the the flurry of excitement generated by the well-publicized pilot study in in 2002 [Shults CW 2002], which reported evidence for slowing of functional decline in 20 Parkinson's patients who received the largest dose of 1200 mg/day. Unfortunately, these results have not been confirmed in more recent CoQ-10 trials with larger numbers of patients.

These recent clinical trials, performed in many more patients than the one in 2002 suggest that there is either no benefit, or it is small enough to go unnoticed clinically for at least the one year time frame. I believe these results cast doubt on significant benefit for Parkinson's. And by extension these results cast more doubt of benefit for Huntington's because CoQ-10 targets mechanisms of mitochondrial oxidative injury that is thought to be similar in both Parkinson's and Huntington's.

Off the HDDW Favorites: As of this week, Coenzyme Q-10 is off the list of the HDDW favorites, and I don't recommend it outside of ongoing clinical trials. Reasons include the great expense of this supplement, and mouse model evidence (unpublished) suggesting that creatine/CoQ-10 combination is no better than creatine alone. But for me, more significant is recent evidence showing lack of benefit in several Parkinson's human trials.


Shults CW, Oakes D, Kieburtz K, Beal MF, Haas R, Plumb S, Juncos JL, Nutt J, Shoulson I, Carter J, Kompoliti K, Perlmutter JS, Reich S, Stern M, Watts RL, Kurlan R, Molho E, Harrison M, Lew M; Parkinson Study Group. Effects of coenzyme Q10 in early Parkinson disease: evidence of slowing of the functional decline. Arch Neurol. 2002 Oct;59(10):1541-50. PubMed abstract

NINDS NET-PD Investigators. A randomized clinical trial of coenzyme Q10 and GPI-1485 in early Parkinson disease. Neurology. 2007 Jan 2;68(1):20-8. PubMed abstract

Storch A, Jost WH, Vieregge P, Spiegel J, Greulich W, Durner J, Müller T, Kupsch A, Henningsen H, Oertel WH, Fuchs G, Kuhn W, Niklowitz P, Koch R, Herting B, Reichmann H; German Coenzyme Q Study Group. Randomized, double-blind, placebo-controlled trial on symptomatic effects of coenzyme Q(10) in Parkinson disease. Arch Neurol. 2007 Jul;64(7):938-44. Epub 2007 May 14. PubMed abstract