Hu, Derek

ABSTRACT Introduction Etripamil is a fast‐acting intranasally self‐administered calcium‐channel blocker developed for termination of paroxysmal supraventricular tachycardia (PSVT). Prior studies have demonstrated safety and efficacy of etripamil for PSVT termination following an initial medically supervised test dose during sinus rhythm. NODE‐303 is an open‐label, single‐arm study that evaluated etripamil for multiple, at‐home PSVT episodes, without test dose before first use. Methods Patients applied an ECG monitor at symptom onset and self‐administered etripamil (70 mg) if a vagal maneuver was unsuccessful. ECG monitoring occurred for ≥ 1 h following study drug administration. A repeat 70‐mg dose was introduced during the study for symptoms persisting 10 min after the first dose. Safety measures included treatment‐emergent adverse events (TEAEs) and ECG arrhythmia‐surveillance. Efficacy measures were captured for PSVT termination during treatment of each of the multiple episodes. Results 1054 perceived PSVT episodes were etripamil‐treated in 503 of 1116 patients enrolled. TEAEs within 24 h were mostly mild or moderate and localized: 30.2% of patients experienced nasal discomfort, nasal congestion (13.9%), rhinorrhea (13.1%), epistaxis (7.4%). TEAE frequencies decreased across multiple PSVT episodes and were similar for single versus repeat doses. For first PSVT episodes, 70.5% of patients converted to sinus rhythm by 60 min post etripamil (median time to conversion = 18.3 min [14.2–25.6]). Conversion in earlier episodes was consistently predictive of conversion in subsequent episodes. Conclusions Etripamil nasal spray self‐administered in a real‐world setting was well tolerated, effective, and had a consistent safety profile as a single‐ or repeat‐dose regimen across multiple PSVT episodes. Trial Registration: ClinicalTrials.gov NCT04072835

Background: Etripamil nasal spray (NS) is a fast acting, self-administered calcium channel blocker in development for the termination of AV-nodal-dependent supraventricular tachycardia (SVT). Prior randomized, placebo-controlled and open-label studies have demonstrated favorable safety and efficacy of etripamil in converting paroxysmal supraventricular tachycardia (PSVT) to sinus rhythm (SR) self-administered without direct medical supervision. Research Question/Hypothesis: To assess patterns and annualized PSVT episode frequency among patients opting to self-administer acute treatment with etripamil. Methods: NODE-303 was an event-driven, multi-center, open-label Phase 3 study, conducted in North and South America to evaluate the safety and efficacy of etripamil in patients with documented PSVT over multiple episodes. Test dosing was not performed prior to at-home use. Enrolled patients, upon perceiving symptoms of PSVT: applied an ambulatory ECG monitor, performed a previously trained vagal maneuver and, if symptoms persisted, self-administered etripamil NS 70 mg. During the study, the protocol was amended to allow a repeat dose (70 mg) if symptoms persisted 10 min after the first dose. Each patient could self-treat up to 4 episodes. Results: Of 1,116 enrolled patients, 503 (45.1%) treated ≥1 perceived PSVT episode (safety population). Etripamil achieved conversion to SR in 60% of patients by 30 minutes and 70% by 60 minutes. A total of 220, 118, 62, and 103 patients completed the study with 1, 2, 3, and 4 etripamil-treated perceived episodes of PSVT, respectively, with an average time on study of 440 days. Among these patients, the average number of annualized etripamil-treated PSVT episodes was 3.2 (standard deviation 3.8). Annualized use: etripamil was self-administered for 0-2 PSVT episodes per year, 2-6 episodes, 6-12 episodes, and >12 episodes, in 54%, 32%, 10%, and 4% of patients, respectively (Figure). Conclusions: This analysis aimed to assess the annualized use of etripamil NS in a real-world setting, by analyzing how often patients would self-administer the drug for PSVT episodes. Of patients that self-administered etripamil (n=503), the majority treated >1 episode and the annualized frequency of episodes treated with etripamil was 3.2 episodes/yr.