Well, if it inhibits, it needs to be renewed at the same rate it is consumed to maintain the inhibition. Thus a saturation dose(freezes ALL that protease inhibition needs to be administered.) The body will degrade/metabolise/excrete this protease = an effective half life. The body's adaptive immune system will also increase to block various aspects of the ways and means the virus uses to reproduce = might block the protease or might stop it being made. In any event this will be a good adjunct to a vaccine to freeze the virus in t's tracks until it can be killed.