ATRIAL FIBRILLATION (AF)
Atrial fibrillation is a disorder in which the normally regular and coordinated contraction pattern of the heart's two small upper chambers (the atria) becomes irregular and uncoordinated. The irregular contraction pattern associated with atrial fibrillation causes blood to pool in the atria, predisposing the formation of clots. These clots may travel from the heart and become lodged in the arteries leading to the brain and other organs, thereby blocking necessary blood flow and potentially resulting in stroke. In addition, in patients with heart failure and reduced left ventricular ejection fraction (HFREF), new onset atrial fibrillation may also contribute to worsening heart failure and increased risk of death. AF is considered an epidemic cardiovascular disease with an estimated prevalence of at least 2.7 million Americans in 2010.
AF CLINICAL TRIAL
GENETIC-AF is a Phase 2B/3, multi-center, randomized, double-blind clinical trial comparing Gencaro to Toprolol-XL for prevention of AF in patients with heart failure and reduced left ventricular ejection fraction (HFREF). ARCA plans to enroll only patients with the genetic variant of the beta-1 cardiac receptor which the Company believes responds most favorably to Gencaro. GENETIC-AF has an adaptive design, under which the Company plans to initiate it as a Phase 2B study in approximately 200 patients and then, depending on the results of an interim analysis by the trial Data Safety Monitoring Board (DSMB), expand the trial to a Phase 3 study by enrolling an estimated additional 420 patients. Screening of patients for enrollment in GENETIC-AF began in April 2014.
Under the collaboration with Medtronic, ARCA plans to conduct a substudy that will include continuous monitoring of the cardiac rhythms of all 200 patients enrolled during the Phase 2B portion of GENETIC-AF. Each patient will have heart rhythm monitoring via a Medtronic device, either a previously implanted cardiac resynchronization or defibrillation device, or a previously or newly inserted Reveal® loop recorder. The collaboration substudy will measure AF burden, defined as a patient’s actual time in AF regardless of symptoms. For the DSMB interim analysis, AF burden and the primary endpoint of the study, time to recurrence of symptomatic AF after electrical cardioversion, or death, will be reviewed by the DSMB to determine if there is sufficient potential for a statistically significant efficacy signal to be determined for all patients enrolled in the Phase 2B/3 study.