Effect of intracoronary administration of AAV1/SERCA2a on ventricular remodelling in patients with advanced systolic heart failure: results from the AGENT-HF randomized phase 2 trial

Aims: Restoration of sarco/endoplasmic reticulum Ca²⁺ ATPase (SERCA2a) activity through gene transfer improved cardiac function in experimental and pilot studies in humans with heart failure. The AGENT-HF (NCT01966887) trial investigated the impact of adeno-associated virus (AAV1)/SERCA2a on ventricular remodelling using multimodality non-invasive cardiac imaging. Methods and results: AGENT-HF was a single centre, randomized, double-blind, placebo-controlled trial in adult patients with NYHA class III–IV ischaemic or non-ischaemic heart failure and left ventricular ejection fraction ≤35%. Eligible patients were randomized to receive a single intracoronary infusion of either 1 × 10¹³ DNase-resistant particles of AAV1/SERCA2a or placebo. The primary endpoint was change in left ventricular end-systolic volume (LVESV), measured by cardiac computed tomography at 6 month follow-up. We planned to include 40 patients but the trial was terminated prematurely as the sponsor suspended further enrolment following neutral results of the CUPID-2 outcome trial. At the time of termination, nine patients were randomized with five patients infused with AAV1/SERCA2a and four with placebo. At 6 months, LVESV was increased in both groups compared with baseline: median (interquartile range) in AAV1/SERCA2a vs. placebo: 13 (13;14) mL vs. 3.5 (−36;36) mL, P = 0.74, with a mean difference between groups of 11.4 mL in favour of placebo. No safety issues were noted. Conclusion: AGENT-HF failed to demonstrate any improvement in ventricular remodelling in response to AAV1/SERCA2a at the dose studied. However, because of premature termination, the study was underpowered to demonstrate an effect of AAV1/SERCA2a and these data should be interpreted with caution.