BackgroundSevere tricuspid regurgitation remains largely undertreated given limited treatment options. Transcatheter tricuspid valve interventions have emerged as a promising therapy for these patients, and the TRISCEND II pivotal trial is the first randomized controlled trial to evaluate transcatheter tricuspid valve replacement (TTVR). ObjectivesThe TRISCEND II pivotal trial studies the transcatheter EVOQUE tricuspid valve replacement system using an FDA Breakthrough Device Designation – a program intended to provide timely access to medical devices by speeding up development, assessment, and review. MethodsThe TRISCEND II trial is a prospective, multicenter trial that randomizes patients with symptomatic severe tricuspid regurgitation to treatment with either TTVR in conjunction with optimal medical therapy or optimal medical therapy alone. The trial's novel 2-phase design evaluates 30-day safety and 6-month effectiveness endpoints for the first 150 patients in the initial phase and a 1-year safety and effectiveness endpoint for the full cohort of 400 patients in the second phase. ResultsThe TRISCEND II trial's 2-phase trial design provided an opportunity for early review and led to the first commercial approval of a TTVR system. ConclusionsThe design of the TRISCEND II trial will likely inform future transcatheter tricuspid device trials. Condensed AbstractThe TRISCEND II pivotal trial is the first randomized controlled trial of transcatheter tricuspid valve replacement (TTVR). It was designed under the FDA's Breakthrough Device Program to bring a novel TTVR therapy to patients with limited treatment options. A 2-phase design allowed for early review of safety and effectiveness outcomes followed by a full-cohort safety and effectiveness endpoint in the second phase at 1 year. This approach led to approval of the first commercial transcatheter therapy for tricuspid valve replacement.