NODE-303 is a multi-center, open label (OL) study to evaluate the safety of etripamil NS in patients with Paroxysmal Supraventricular Tachycardia (PSVT). Patients will be provided with an ambulatory Cardiac Monitoring System (CMS) to help document PSVT episodes. The CMS will be self-applied by the patient, when they feel the onset of PSVT symptoms. Patients will self-administer etripamil NS if vagal maneuver is ineffective. After an episode of PSVT where drug is administered, the patient will return to the investigative site and have the option to continue in NODE-303 and manage subsequent episodes of PSVT with etripamil NS.~The study will include:~A Screening Visit during which the Investigator will verify that the patient meets the eligibility criteria of the NODE-303 study, will obtain the signed informed consent, take blood and urine for laboratory evaluations, and conduct other screening procedures. The informed consent for NODE-303 will be applicable for the initial and all subsequent PSVT episodes. A Baseline Visit during which the site will confirm eligibility, concomitant medications, train the patient on study procedures, and give the patient study drug, patient reported outcome (PRO) materials, and the CMS materials. A Treatment Period during which the patient will complete the monthly PRO survey, self-identify symptoms of PSVT, use the CMS, perform a vagal maneuver (VM), and self-administer etripamil NS if the symptoms do not resolve during or after the VM. Patients may be contacted during this period for reminders and training on what to do during a PSVT episode. Patients will also complete a per episode survey after any PSVT episode they experience. During the Treatment Period, Follow-up Visits will occur at the study site up to 14 days after each episode of PSVT which is treated with etripamil NS, and during which the Investigator will evaluate the results of the last usage of etripamil NS and reassess patient's eligibility to continue in the study based on study inclusion and exclusion criteria. Patients who are eligible to continue in the study will receive two additional kits containing study medication.~A Final Study Visit that will occur when a patient discontinues or withdraws from the study, or when the overall study is completed, or the patient has completed the maximum number of doses. NODE-303 will continue until enough documented self-administrations of etripamil NS are included in the safety database to meet regulatory requirements for the etripamil NS development program. The common study end date (CSED) for the entire study will depend on the rate of accrual of the primary endpoint, unique patients with an episode. When the criteria for concluding the study have been met, the Sponsor will announce the common study end date (CSED) for the entire study and sites will be informed in advance to schedule all final patient visits prior to the CSED.
NODE-303 is a multi-center, open label (OL) study to evaluate the safety of etripamil NS in patients with Paroxysmal Supraventricular Tachycardia (PSVT). Patients will be provided with an ambulatory Cardiac Monitoring System (CMS) to help document PSVT episodes. The CMS will be self-applied by the patient, when they feel the onset of PSVT symptoms. Patients will self-administer etripamil NS if vagal maneuver is ineffective. After an episode of PSVT where drug is administered, the patient will return to the investigative site and have the option to continue in NODE-303 and manage subsequent episodes of PSVT with etripamil NS.