ARCA biopharma, Inc. is a clinical stage biopharmaceutical company engaged in the development and commercialization of targeted therapies for cardiovascular diseases. The Company's lead product candidate is Gencaro (bucindolol hydrochloride) for the treatment of atrial fibrillation (AF), in patients with chronic heart failure (HF). Gencaro is being developed for patients who have a genotype that identifies a drug target associated with heightened efficacy. Gencaro is a pharmacogenetically-targeted beta-adrenergic receptor antagonist with mild vasodilator properties that the Company is developing for the treatment of AF in patients with heart failure. The Company's Recombinant Nematode Anticoagulant Protein c2 (rNAPc2) (AB201), is a protein therapeutic in clinical development as a potential treatment for patients with COVID-19. The rNAPc2 is in a phase IIb clinical trial as a potential treatment for patients hospitalized with COVID-19.