SIMPLIFICATION STUDY OF HIV-1 INFECTED PATIENTS WITH VIROLOGICAL SUPPRESSION UNDER THE COMBINATION OF LAMIVUDINE (150 MG BID) PLUS RALTEGRAVIR (400 MG BID) SWITCHING TO LAMIVUDINE (300 MG QD) PLUS RALTEGRAVIR (1200 MG QD) : ROLL-OVER STUDY OF THE RALAM: