The invention relates to a combination comprising an effective amount of (i) a 5-phenoxy-3H-pyrimidin-4-one derivative of Formula I: or a pharmaceutically acceptable salt thereof wherein M is CH2, CH 2 CH 2 , CH 2 CH 2 CH 2 , CH(CH 3 ), C(CH 3 ) 2 or C(O)N(R A ), and Z is selected from the group consisting of: pyridazine, pyridazinone, pyrimidine, pyrimidinone, pyrazine, pyrazinone, triazine and triazinone, each optionally substituted with one or more substituents up to the maximum number allowed by valence selected from R 4 and R 5 , and (ii) one or more anti-HIV agent(s). The invention further relates to use of said combination for the prophylaxis or treatment of infection by HIV or for the prophylaxis, treatment, or delay in the onset of AIDS in a subject.
