2. Stop therapy. This strategy is feasible in patient with relatively preserved immune function. Time off antiretroviral therapy would be highly dependent on previous nadir CD4 cell count (the lowest the nadir, the more rapidly patients loses CD4 cells). In patients with multidrug resistant virus this strategy is used with the goal of achieving virus reversion towards wild-type forms. Reversion towards wild-type virus would theoretically "resensitize" HIV to prior failed drugs. Unfortunately, a number of investigations have suggested that the loss of CD4 cell count occurred during the time off therapy might not be regained after starting rescue therapy. In addition, reversion towards wild type virus does not appear to be associated with a more favourable outcome of rescue therapy.