I don't think there is any single simple cure, much less biologically based one.

BP is seems too spiritual and sociologically based for that. There are plenty of heavily medicated bipolars and still not cured. The people that found some solace found it outside of the pill bottle. Taking or not taking meds does not seem really matter in the larger aspect of having meaningful existance and finding the inner peace. Meds only calm you down enough to make your more bearable or less threatening to others, numb you from your realities... the more we explore the MI from sciency view point, the more does the general unsatisfaction and unhappiness increase.