This study comprises two steps. In Step I, participants will be randomly assigned to receive either fish oil supplements or fenofibrate. Participants will be evaluated for treatment response at Week 8. Those who have responded to their treatment will remain on their original single agent therapy through Week 18. Those who have not responded to treatment at Week 10 will move on to Step 2 and begin combination therapy with both fenofibrate and fish oil until Week 18. All participants will return at Week 22 for a follow-up visit. Except at the Week 10 visit, participants will be expected to fast prior to all study visits. Participants will remain on their individual HAART regimens for the duration of the study.