title: Non-invasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA(3)CT): Design of a Phase IIb, placebo-controlled, double-blind, randomized clinical trial of doxycycline for the reduction of growth of small abdominal aortic aneurysm.
abstract: The Non-Invasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA(3)CT) is a Phase IIb randomized, placebo-controlled clinical trial, testing doxycycline (100mg bid) for inhibition of growth in the greatest transverse, orthogonal diameter of small abdominal aortic aneurysms (AAA).
  
  
  
  We will enroll 258 patients, ≥55years of age who have AAA, men: 3.5-5.0cm and women: 3.5-4.5cm on CT scans confirmed centrally. The primary outcome is growth in maximal transverse, orthogonal diameter from baseline to 24-month follow-up. Secondary analyses address doxycycline effects on clinical events, aneurysm volume, and biomarkers. Primary analysis will be performed according to the principle of intention-to-treat accounting for death and ruptures by use of normal scores in analysis of covariance. At the time of the data file reported, 200 subjects have been randomized. We started enrollment in mid-2013 and will complete enrollment by mid-2016.
  
  
  
  Participant average age=70.9years, (SD=7.6years) and maximum transverse diameter=4.3cm for men (SD=0.4) and 4.0cm for women (SD=0.3).
  
  
  
  N-TA(3)CT is a critical experiment to determine whether doxycycline reduces growth of small AAA and systemic markers of inflammation previously seen in bench experiments and observational human studies to be associated with AAA growth. Our patient population baseline measurements agree with the design assumptions supporting our expectation of 90% power or greater to reject a null hypothesis in favor of an alternative hypothesis when growth is reduced by at least 40%.
  
  
  
  clinicaltrials.gov #NCT01756833.
authors.affiliation: University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE 68198, United States.
authors.forename: B Timothy
authors.initials: BT
authors.lastname: Baxter
authors.affiliation: University of Wisconsin, Medicine and Public Health, 600 Highland Avenue, Madison, WI 53792, United States.
authors.forename: Jon
authors.initials: J
authors.lastname: Matsumura
authors.affiliation: Vanderbilt University, Vascular Surgery, 1161 21st Avenue South, Nashville, TN 37232, United States.
authors.forename: John
authors.initials: J
authors.lastname: Curci
authors.affiliation: Axio Research, 2601 4th Avenue, Seattle, WA 98121, United States.
authors.forename: Ruth
authors.initials: R
authors.lastname: McBride
authors.affiliation: University of Maryland School of Medicine, 685 W. Baltimore Street, Baltimore, MD 21201, United States.
authors.forename: William C
authors.initials: WC
authors.lastname: Blackwelder
authors.affiliation: University of Maryland School of Medicine, 660 W. Redwood Street, Baltimore, MD 21201, United States.
authors.forename: Xinggang
authors.initials: X
authors.lastname: Liu
authors.affiliation: University of Nebraska Medical Center, 983280 Nebraska Medical Center, Omaha, NE 68198, United States.
authors.forename: LuAnn
authors.initials: L
authors.lastname: Larson
authors.affiliation: University of Maryland School of Medicine, 660 W. Redwood Street, Baltimore, MD 21201, United States. Electronic address: mterrin@epi.umaryland.edu.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Terrin
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000473:pathology; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000188:drug therapy*; D004311:Double-Blind Method; D004318:Doxycycline / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D004318:Doxycycline
keywords: Abdominal; Aneurysm; Aortic; Clinical trial; Doxycycline