IL-1 Blockade in Patients With Heart Failure With Preserved Ejection Fraction.

Background Enhanced inflammation may lead to exercise intolerance in heart failure with preserved ejection fraction. The aim of the current study was to determine whether IL (interleukin)-1 blockade with anakinra improved cardiorespiratory fitness in heart failure with preserved ejection fraction. Methods and Results Thirty-one patients with heart failure with preserved ejection fraction and CRP (C-reactive protein) >2 mg/L were randomized to anakinra (100 mg subcutaneously daily, N=21) or placebo (N=10) for 12 weeks. We measured peak oxygen consumption (Vo(2)), ventilatory efficiency (V-E/Vco(2) slope), and high-sensitivity CRP and NT-proBNP (N-terminal pro-B-type natriuretic peptide) at 4, 12, and 24 weeks. Twenty-eight patients completed 2 visits, 18 women (64%), 27 (96%) obese. There were no differences in peak Vo(2) or V-E/Vco(2) slope between groups at baseline. Peak Vo(2) was not changed after 12 weeks of anakinra (from 13.6 [11.8-18.0] to 14.2 [11.2-18.5] mLkg(-1)min(-1), P=0.89), or placebo (14.9 [11.7-17.2] to 15.0 [13.8-16.9] mLkg(-1)min(-1), P=0.40), without significant between-group differences in changes at 12 weeks (-0.4 [95% CI, -2.2 to +1.4], P=0.64). V-E/Vco(2) slope was also unchanged with anakinra (from 28.3 [27.2-33.0] to 30.5 [26.3-32.8], P=0.97) or placebo (from 31.6 [27.3-36.9] to 31.2 [27.8-33.4], P=0.78), without significant between-group differences in changes at 12 weeks (+1.2 [95% CI, -1.8 to +4.3], P=0.97). Within the anakinra-treated patients, high-sensitivity CRP and NT-proBNP levels were lower at 4 weeks compared with baseline (P=0.026 and P=0.022 versus placebo [between-group analysis], respectively). Conclusions Treatment with anakinra for 12 weeks failed to improve peak Vo(2) and V-E/Vco(2) slope in a group of obese heart failure with preserved ejection fraction patients. The favorable trends in high-sensitivity CRP and NT-proBNP with anakinra deserve exploration in future studies. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT02173548.