In patients with peripheral artery disease (PAD), supervised treadmill exercise may improve walking performance, whereas granulocyte-macrophage colony-stimulating factor (GM-CSF) either alone or in combination with exercise showed no improvement, according to results from the PROPEL trial presented November 15, at American Heart Association (AHA) Scientific Sessions 2017, and simultaneously published in the Journal of the American Medical Association.

Mary M. McDermott, MD, et al., looked at 210 patients with PAD who were randomized to receive supervised exercise + GM-CSF (n=53); supervised exercise alone (n=53); GM-CSF alone (n=53); or attention control + placebo (n=51). Supervised exercise included treadmill exercise three times weekly for six months. Attention control included weekly educational lectures by clinicians for six months.

Results showed that at 12-weeks, exercise + GM-CSF "did not significantly improve 6-minute walk distance" more than exercise alone (mean difference, ?6.3m [95% CI, ?30.2 to +17.6]; P=0.61), or more than GM-CSF alone (mean difference, +28.7m [95% CI, +5.1 to +52.3]; Hochberg-adjusted P= 0.052).

The authors conclude that their results "confirm the benefits of exercise but do not support using GM-CSF to treat walking impairment in patients with PAD."