DITPA (3,5-Diiodothyropropionic Acid), a Thyroid Hormone Analog to Treat Heart Failure Phase II Trial Veterans Affairs Cooperative Study

Background-In animal studies and a pilot trial in patients with congestive heart failure, the thyroid hormone analog 3,5 diiodothyropropionic acid (DITPA) had beneficial hemodynamic effects. Methods and Results-This was a phase II multicenter, randomized, placebo-controlled, double-blind trial of New York Heart Association class II to IV congestive heart failure patients randomized (2: 1) to DITPA or placebo and treated for 6 months. The study enrolled 86 patients (n = 57 to DITPA, n = 29 to placebo). The primary objective was to assess the effect of DITPA on a composite congestive heart failure end point that classifies patients as improved, worsened, or unchanged based on symptom changes and morbidity/mortality. DITPA was poorly tolerated, which obscured the interpretation of congestive heart failure-specific effects. Fatigue and gastrointestinal complaints, in particular, were more frequent in the DITPA group. DITPA increased cardiac index (by 18%) and decreased systemic vascular resistance (by 11%), serum cholesterol (-20%), low-density lipoprotein cholesterol (-30%), and body weight (-11 lb). Thyroid-stimulating hormone was suppressed in patients given DITPA, which reflects its thyromimetic effect; however, no symptoms or signs of potential hypothyroidism or thyrotoxicosis were seen. Conclusions-DITPA improved some hemodynamic and metabolic parameters, but there was no evidence for symptomatic benefit in congestive heart failure. (Circulation. 2009; 119: 3093-3100.)