Also note when researching - many people prescribe naltrexone to be taken every day along with abstinence, and infact when taken this way it's shown to be no better than a placebo. When taken as per The Sinclair Method it has been shown to be over 85% effective.
Having participated in a number of eating disorder groups and also having studied it, I feel sure that is not the case.
Edit: (Assuming that the prior commenters method _is_ effective)
Relevant: http://existentialcomics.com/comic/13
People undergoing The Sinclair Method often find there are two parts to their addiction - the chemical part, and the habitual part. Sometimes once the chemical part is extinguished they also have the habitual part to stop.
There are questionnaires you can take to reveal how much your addiction is chemical led e.g. do you smoke first thing in the morning (when the chemical levels are low) or do you smoke as part of some routine.
What levels of effectiveness is that. Placebo's are reported as being pretty strong medicine: no better than placebo is pretty good if your placebo is effective in 40% of cases for example.
Unless this drug has a 100% success rate I take the placebo observation as a valid one. But it should not 100% discount the drug efficacy out of hand either.