Lung-to-Heart Nano-in-Micro Peptide Promotes Cardiac Recovery in a Pig Model of Chronic Heart Failure

BACKGROUND The lack of disease -modifying drugs is one of the major unmet needs in patients with heart failure (HF). Peptides are highly selective molecules with the potential to act directly on cardiomyocytes. However, a strategy for effective delivery of therapeutics to the heart is lacking. OBJECTIVES In this study, the authors sought to assess tolerability and efficacy of an inhalable lung -to -heart nano -inmicro technology (LungToHeartNIM) for cardiac -specific targeting of a mimetic peptide (MP), a first -in -class for modulating impaired L -type calcium channel (LTCC) trafficking, in a clinically relevant porcine model of HF. METHODS Heart failure with reduced ejection fraction (HFrEF) was induced in Gottingen minipigs by means of tachypacing over 6 weeks. In a setting of overt HFrEF (left ventricular ejection fraction [LVEF] 30% +/- 8%), animals were randomized and treatment was started after 4 weeks of tachypacing. HFrEF animals inhaled either a dry powder composed of mannitol-based microparticles embedding biocompatible MP -loaded calcium phosphate nanoparticles (dpCaP-MP) or the LungToHeartNIM only (dpCaP without MP). Efficacy was evaluated with the use of echocardiography, invasive hemodynamics, and biomarker assessment. RESULTS DpCaP-MP inhalation restored systolic function, as shown by an absolute LVEF increase over the treatment period of 17% +/- 6%, while reversing cardiac remodeling and reducing pulmonary congestion. The effect was recapitulated ex vivo in cardiac myofibrils from treated HF animals. The treatment was well tolerated, and no adverse events occurred. CONCLUSIONS The overall tolerability of LungToHeartNIM along with the beneficial effects of the LTCC modulator point toward a game -changing treatment for HFrEF patients, also demonstrating the effective delivery of a therapeutic peptide to the diseased heart. (J Am Coll Cardiol 2024;83:47-59) (c) 2024 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).