Axon’s Transcatheter SAVM Therapy Studied for Treating Patients With HFpEF

October 8, 2023—Axon Therapies announced 6-month results from the randomized, blinded REBALANCE-HF feasibility trial of splanchnic ablation for volume management (SAVM) for patients with heart failure with preserved ejection fraction (HFpEF).

The company stated that SAVM with its Satera ablation system is a frontline transcatheter therapy that aims to reduce sympathetic tone, enabling targeted venodilation of the splanchnic bed to normalize blood volume in the heart and lungs and prevent congestion. The therapy is intended to calm the overactive sympathetic nervous system by using unilateral radiofrequency to selectively ablate the greater splanchnic nerve.

The main objectives of the study were to demonstrate safety, evaluate the ease and repeatable nature of the procedure, and identify the subtype of patients most likely to respond to the therapy to inform future clinical trials. REBALANCE-HF is enrolling 116 patients at 18 sites.

The REBALANCE-HF results were presented by Marat Fudim, MD, during the late-breaking clinical trials session at HFSA 2023, the annual scientific meeting of the Heart Failure Society of America held October 6-9 in Cleveland, Ohio. Dr. Fudim is an advanced heart failure specialist at Duke University Medical Center in Durham, North Carolina.

According to the company, although there was no improvement with the SAVM procedure compared to a control sham procedure in the full study cohort, the preliminary results showed that HFpEF patients who are sensitive to acute shifts in blood volume during exercise or stress were more likely to be responsive to SAVM. The responder group, which made up more than half of the full cohort, saw clinically meaningful improvements in functional capacity, symptoms, and quality-of-life metrics at 6 months after treatment with SAVM.

Sanjiv Shah, MD, is Principal Investigator for the REBALANCE-HF early feasibility trial. Dr. Shah is an advanced heart failure specialist and Director of Research at Bluhm Cardiovascular Institute at Northwestern University Feinberg School of Medicine in Chicago, Illinois.

“SAVM utilizes a novel mechanism of action for treating heart failure, so we designed the REBALANCE-HF early feasibility trial to enable us to identify potential responder groups from a broad range of HFpEF patients,” commented Dr. Shah in Axon Therapies’ press release. “These results show that HFpEF patients who are able to augment cardiac output during exertion and those without advanced structural heart disease may benefit most from SAVM.”

The company further reported in the press release that the full treatment arm results confirmed the SAVM procedure was safe, with no difference in procedure-related adverse events compared to the sham arm. SAVM was performed quickly (53 minutes on average) and had a 98% procedural success rate. The improvements SAVM demonstrated in the responder group at 6 months were sustained in patients who have available 12-month data.

As outlined in Axon Therapies’ press release, key results include:

• 13-point improvement in quality of life at 6 months in treatment versus sham (P = .02) as measured by Kansas City Cardiomyopathy Questionnaire score.
• 36-meter improvement in ability to walk at 6 months in treatment versus sham (P = .08) as measured by the 6-minute walk test.
• 39% relative improvement in cardiac function (N-terminal-pro brain natriuretic peptide measures) at 6 months in treatment versus sham (P = .10).
• Reduced filling pressures at 1 month as measured by peak pulmonary capillary wedge pressure of −4.5 mm Hg versus −1.6 mm Hg for sham (P = .10)

Dr. Fudim concluded in the press release, “The favorable hemodynamics and improvements in clinical symptoms in this responder population versus the sham group is promising. Although we need additional data to confirm the results, the easy-to-perform SAVM procedure has the potential to become a frontline interventional procedure and change how we treat HFpEF patients, a notoriously complex population that makes up at least 50% of heart failure patients.”