Atherosclerotic inflammation can be non-invasively and reproducibly measured with FDG-PET/CT imaging, a well-validated quantitative technique that can sensitively detect changes in atherosclerotic inflammation. FDG-PET/CT imaging has been employed in several multi-center trials to measure changes in arterial inflammation in response to anti-inflammatory treatments. Accordingly, we propose a time sensitive ancillary imaging study to determine if treating virologically suppressed, HIV-infected individuals with LDMTX reduces atherosclerotic inflammation, assessed by FDG-PET/CT. Our central hypothesis is that persistent immune cell activation results in chronic arterial inflammation, which subsequently contributes to the CVD risk observed in HIV. This fully integrated ancillary study would, in a subset of patients enrolled in the parent trial: (i) assess the impact of LDMTX on arterial inflammation, and (ii) identify the immune cell subtypes whose changes (with LDMTX) are associated with changes in arterial inflammation. Accordingly, the proposed ancillary study would provide unique and highly complementary information that would greatly increase the knowledge and mechanistic insights gained from the Parent Study. The ancillary study has two specific aims: