Effect of propionyl-L-carnitine on a background of monitored exercise in patients with claudication secondary to peripheral artery disease.

Exercise training is established for the treatment of peripheral artery disease; however the additional benefit of pharmacologic therapy with exercise has not been studied. This trial tested the hypothesis that propionyl-L-carnitine (PLC), in combination with monitored home-based exercise training, would improve treadmill peak walking time (PWT) over exercise training alone. Subjects with claudication were randomized to 6 months of therapy with PLC (2 g daily, n = 32) or matching placebo (n = 30). After supervised exercise instruction, all subjects performed exercise training sessions 3 times a week for 30 to 50 minutes/session and compliance was monitored by activity monitors and diary. Change in PWT was the primary outcome measure with other functional assessments predefined as secondary endpoints. After 6 months of treatment, patients randomized to training and placebo had an increase in PWT of 218 ± 367 seconds, while those randomized to training plus PLC had an increase of 266 ± 243 seconds, P = .258. Across the total study cohort, the dose of exercise training (total number of minutes of exercise of at least moderate intensity) was correlated with the change in PWT (r = 0.259, P = .048), suggesting that the monitored exercise was effective in improving walking performance in both treatment arms. In all subjects, the increase in PWT from baseline to month 6 was correlated with the amount of exercise training. However, although favoring PLC, the combination of exercise training and PLC did not result in a statistically significant benefit in peak treadmill performance or quality of life compared with exercise alone.