A total of 267 participants required treatment ( 94 received placebo , 87 received 1200 mg/d of CoQ10 , and 86 received 2400 mg/d of CoQ10 ) , and 65 participants ( 29 who received placebo , 19 who received 1200 mg/d of CoQ10 , and 17 who received 2400 mg/d of CoQ10 ) withdrew prematurely .