Trial 3: FER-CARS-05 (CONFIRM-HF) was a randomized, double-blind, placebo-controlled, study in patients with iron deficiency and chronic heart failure with left ventricular ejection fraction of < 45% and New York Heart Association (NYHA) class II/III to determine whether intravenous ferric carboxymaltose improves exercise capacity measured as change from baseline to 24 weeks in 6-minute walk distance (6MWD).
Iron deficiency was defined as serum ferritin < 100 ng/mL or 100 to 300 ng/mL with TSAT < 20%. Patients with Hb of ≥ 15 g/dl were excluded. Of the 304 patients, 150 were randomized to ferric carboxymaltose and 151 to placebo. The median age of study patients was 71 years (range, 35 to 88); 46% were female; 99% were Caucasian.
At baseline, mean (SD) Hb was 12 g/dl (1.4), ferritin 57 ng/ml (45), TSAT 19 % (13.7), LVEF 37% (7), brain natriuretic peptide 770 pg/mL (973); and 57 and 43% were classified as NYHA class II and III, respectively.
At baseline, 95% of patients were treated with angiotensin converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB), 91% with beta-blocker, 59% with aldosterone antagonists, and 90% with diuretic.
The mean change in 6MWD from Baseline to Week 24 in ferric carboxymaltose-treated patients was 18 meters (95% CI 4, 32), and placebo-treated patients was -7 meters (95% CI -21, 7), with between group difference of 25 meters (7, 43), p-value 0.007, favoring ferric carboxymaltose. Results were generally similar within age and sex subgroups.
In ferric carboxymaltose-treated patients, change from Baseline to Week 24 in serum ferritin was 269 ng/mL (229, 309), in TSAT was 9% (7, 11), and in Hb was 0.6 g/dL (0.3, 0.8).