Patient preference for subcutaneous vs. intravenous immune therapy (PSI-Immune).

TPS1678 Background: Immune checkpoint blockade (ICB) has improved outcomes for patients (pts) with advanced solid tumors. Conventional intravenous (IV) route of administration (RoA) requires repeated, time-intensive infusions involving cannulation, monitoring, pharmacy preparation, and chair time, increasing treatment burden and constraining infusion center capacity, staffing, and scalability as ICB use expands. Subcutaneous (SC) formulations of pembrolizumab and nivolumab—two widely used PD-1 inhibitors—have recently been approved across multiple indications. PD-1 ICB SC formulations contain the same active drug as IV formulations and have demonstrated comparable PK exposure, efficacy and safety profiles (CheckMate 8KX; 3475A-D77). Beyond pt convenience, SC RoA may enable more scalable delivery by reducing infusion chair utilization, nursing time, and workflow bottlenecks, supporting access across high-volume cancer networks. Real-world pt preference and perceived health-system impact of SC versus IV PD-1 ICB remain incompletely characterized. We therefore designed a distributed, real-world clinical trial to evaluate patient preference and health-system implications of PD-1 ICB RoA across a large integrated cancer network (>70 sites across 4 states). Methods: PSI-Immune is a randomized, phase II, open-label, crossover study evaluating pt preference for SC versus IV RoA of PD-1 ICB in pts with locally advanced (LA) or advanced/metastatic (A/M) solid tumors pending initiation PD-1–based therapy, either as monotherapy or in combination. The primary endpoint is pt preference for ICB RoA, assessed using a validated pt preference questionnaire (PPQ). Key secondary endpoints include pt-reported treatment satisfaction (TASQ), HCP-reported time and resource utilization, pt-reported health-related quality of life (HRQoL), and time to next therapy (TTNT). A subcohort permits enrollment of pts who are already on IV PD-1 ICB. Eligible pts must have an FDA-approved indication for SC pembrolizumab or nivolumab singly or in combination with other FDA-approved agents and a planned duration of PD-1–based therapy exceeding six months. Patients are randomized 1:1 to receive either SC therapy for three cycles followed by IV therapy for three cycles, or the reverse sequence (crossover phase). Subsequently, pts select their preferred route of administration (continuation phase). Treatment regimen is identical across cohorts and differs only by ICB RoA. Randomization is stratified by disease setting (LA vs A/M) and ICB regimen (monotherapy vs combination). The planned sample size is 280 patients. Assuming equal allocation and up to 10% attrition, the exact 95% confidence interval for the proportion of patients preferring SC administration will exclude 50% if the observed preference rate is at least 60%. This study is open and enrolling across the entire UPMC Hillman Cancer Center Network (NCT07223424). Clinical trial information: NCT07223424 .