Non-Invasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA^3CT )

DESCRIPTION (provided by applicant): Abdominal aortic aneurysms (AAA) are a common (2-5% of the population e 65 years: 4-9% men;0.5- 1.5% women) and lethal problem causing 15,000 deaths annually from rupture in the U.S. The only accepted treatment is repair of the AAA which is performed for 40,000 large AAA annually in the U.S. With recent, widespread screening, many more small (40%) the growth of small (3.5 - 5.0 cm in men, 3.5 - 4.5 cm in women) infrarenal AAA. We will determine the effects of doxycycline on the expansion rate of small AAA over a 24-month period for all patients with allowance made for outcomes missing for cause (death or aneurysm repair) or undetermined reasons. This will be done through a prospective, double blind, placebo controlled clinical trial of 248 patients. Patients will be randomly assigned to receive placebo or doxycycline (100 mg bid). The primary end point will be aneurysm growth rate determined by semiannual CT scan. The public health impact of testing the safety and efficacy of doxycycline in the treatment of abdominal aortic aneurysms derives from the absence of any medical therapy to avoid open surgery or endograft repair. Without medical therapy, ultrasound screening is considered cost-effective in selected patients only. Effective medical therapy would make early detection even more acceptable by providing an alternative to invasive repair of AAA. PUBLIC HEALTH RELEVANCE: The public health impact of testing the safety and efficacy of doxycycline in the treatment of abdominal aortic aneurysms derives from the large number of patients (hundreds of thousands) who could avoid open surgery or endograft repair (saving in excess of $500,000,000 per year) or, if we do not find doxycycline to be beneficial, who could avoid having an inefficacious therapy recommended. This clinical trial will be definitive for the management of small abdominal aortic aneurysm patients because progression to aneurysm repair is the state-of-the-art management for a known aneurysm that reaches a diameter threshold associated with increased risk of rupture.