ggwpq: an active moiety is the chemical that makes the drug work the way it does. For example, Erythromycin is an antibiotic which fights infection. If you mix it with an ingredient as aspirin, it would also fight infection, but Erthromycin would still be the active moiety. Lovaza is a substance including EPA,DHA, and several other molecules(ingredients). It is not any one ingredient but the combination, which makes the drug work the way it does with some good effects as lowering the trig levels and some bad effects, such as raising LDL levels. The COMBINATION is the active moiety in Lovaza, whereas, in Vascepa, the EPA is the active moiety with much different results. Therefore Vascepa should have been awarded the NCE designation.