ブラインド化は倫理的に正しいか？

一次予防としてのARTの効果を示したスタディーが昨年話題になった。ブラインド化したＲＣＴなんだけど、確かに「型」の上ではよろしいのだが、根源的に考えて倫理的にどうなの？とレターを出してみた。残念ながらリジェクトされたが、みなさんはどう思いますか？考えてみてください。

Preexposure Chemoprophylaxis for HIV Prevention in Men Who Have Sex with Men　N Engl J Med 2010; 363:2587-2599

Dear Editor. We have ethical concern regarding the study by Grant et al,1 We believe the subjects should not have been blinded and the trial should have been conducted open-label. As pointed out in Discussion, blinding could have resulted in subjects' lower adherence. Better adherence could be achieved by notifying the allocation to FTC-TDF group, with further decrease in HIV transmission. Furthermore, better adherence will reveal more accurate side effects profile. On the other hand, placebo group might have false sense of security with riskier behavior. If they were told they were taking placebo, some HIV transmissions could have been avoided. Seventy percent of placebo group suffered some adverse effects, and some, if not most, are probably due to "placebo effect", which could also be avoided by prior notification. Unlike most trials, making open-label will not impair the quality of this study since it is hard to believe that taking FTC-TDF would lead to safer behavior than placebo. Open- label may decrease the probability of positive result, but we should not barter away ethical quality.