Why the NIH Trial to Assess Chelation Therapy (TACT) should be abandoned.

The National Institutes of Health (NIH) Trial to Assess Chelation Therapy (TACT) was begun in 2003 and is expected to be completed in 2009. It is a trial of office-based, intravenous disodium ethylene-diamine-tetra-acetic acid (Na(2)EDTA) as a treatment for coronary artery disease (CAD). A few case series in the 1950s and early 1960s had found Na(2)EDTA to be ineffective for CAD or peripheral vascular disease (PVD).