INhalation of Flecainide to Convert Recent Onset SympTomatic Atrial Fibrillation to siNus rhyThm (INSTANT)

The study consisted of 3 parts (Part A, Part B and Part C). Part A was an open-label, randomized, multi center design to evaluate the feasibility of administration of inhaled flecainide in two dosing regimens. Part B was an open-label, multicenter design to confirm the safety (including tolerability) and efficacy of the optimal inhaled flecainide dose determined from Part A. Part C was an open-label, multi center study with exploratory objectives to explore the feasibility of patient-led self administration of flecainide. Part C also included an exploratory sub-study to assess the feasibility of implementing a portable cardiac ultrasound (HHE) at screening in an emergent setting.