Lipoatrophy is prevalent on thymidine NRTIs (tNRTI). A pilot trial showed that uridine (NucleomaxX®) increased limb fat.
A5229 was a multicenter trial in which HIV-infected individuals with lipoatrophy on tNRTI-regimens were randomized to NucleomaxX or placebo. Primary endpoint was change in limb fat from baseline to week-48. The study was powered to detect 400-gram difference between arms at week-48. A stratified Wilcoxon rank-sum test was used to assess between-arm differences.
The 165 subjects were 91% male, 62% white; median age 49 years, CD4 506 cells/mm3, and limb fat 3037 grams; 81% had HIV-1 RNA ≤50 copies/mL; 76% were on AZT. Baseline characteristics were similar between groups. Only 59% completed 48-weeks of treatment, however only 3 subjects (1 on uridine) discontinued due to toxicity (diarrhea). In intent-to-treat, there was no difference for changes in limb fat between treatments at week-24 or week-48. On as-treated analysis, uridine resulted in an increase in %limb fat vs. placebo (3.4% vs. −0.8%, p=0.01) at week-24 but not at week-48 (1.8% vs.3.8%, p=0.93). Similar results were seen when limiting the analysis to subjects with ≥80% adherence. The results were not related to severity of lipoatrophy or type of tNRTI. No changes were found in facial-anthropometrics, fasting lipids, trunk-fat, CD4, or HIV-RNA.
We found a modest transient improvement in limb fat after 24 weeks of uridine. The lack of sustained efficacy at week-48 was not due to changes in adherence or reduction in sample size. Uridine was safe and did not impair virologic control.