Prolonged administration of doxycycline in patients with small asymptomatic abdominal aortic aneurysms: report of a prospective (Phase II) multicenter study.

Background: The primary purpose of this study was to evaluate compliance, side effects, and safety associated with prolonged administration of doxycycline in patients with small asymptomatic abdominal aortic aneurysms (AAAs). A secondary goal was to determine how treatment with doxycycline influences circulating levels of matrix metalloproteinase-9 (MMP-9) in this patient population.

Methods: Thirty-six patients with AAAs (30 men and 6 women; mean age, 69 +/- 1 years) were enrolled into a 6-month phase II study to evaluate treatment with doxycycline (100 mg orally twice a day).

Doxycycline in patients with abdominal aortic aneurysms and in mice: comparison of serum levels and effect on aneurysm growth in mice.

Objective: Doxycycline has been shown to inhibit aneurysm formation in a rodent model of abdominal aortic aneurysm (AAA). The doses necessary for this inhibition (6 mg/kg) are much higher than the standard antibiotic doses (1 to 1.5 mg/kg) used in humans.