Clinical trials in dementia with propentofylline.

The mode of action of propentofylline (a xanthine derivative) suggested that it would have beneficial effects in patients with Alzheimer's disease or vascular dementia. In four double-blind, placebo-controlled, randomized studies, 901 patients with mild to moderate Alzheimer's disease and 359 patients with mild to moderate vascular dementia were treated for up to 12 months (daily dose of propentofylline: 3 x 300 mg taken 1 hr before food). Patients were assessed at regular intervals for efficacy and safety of the drug. Efficacy variables covered cognitive and global functions as well as activities of daily living. Propentofylline showed statistically significant, clinically relevant improvements over placebo in efficacy assessments, both in patients with Alzheimer's disease and in patients with vascular dementia. The drug was also well tolerated. It had no significant effects on laboratory findings and the adverse events that were considered to be related to the study medication were mostly minor, transient, and affected the digestive and nervous systems.