Multiple sclerosis therapeutic strategies: Use second-line agents as first-line agents when time is of the essence.

M ultiple sclerosis (MS) is a damaging CNS disease. Because the CNS has inherent properties that prevent the damage from manifesting readily (e.g., redundancy, plasticity, repair), often irreversible damage is not appreciated until very late. Pathologically it is apparent that permanent and irreversible damage occurs very early in MS plaque formation. Treatment of the disease course can therefore be viewed as having 3 goals: