A prospective, randomized, blinded, placebo-controlled, phase IIb trial of an autologous tumor lysate + yeast cell wall particles (YCWP) + dendritic cells (DC) vaccine vs unloaded YCWP + DC and embedded phase I/IIa trial with tumor lysate particle only (TLPO) vaccine in stage III and stage IV (resected) melanoma to prevent recurrence.

TPS201Background: Melanoma is a potentially lethal skin malignancy; patients with stage III/IV resected disease have a recurrence rate of 50-90%. Adjuvant checkpoint inhibitor immunotherapy decreases the risk of recurrence but also causes significant immune-related toxicity. Vaccines are a promising strategy for patients with high risk melanoma. The optimal time to intervene may be in the adjuvant setting after attaining a disease-free state through standard of care therapies. Our strategy uses autologous tumor lysate (TL) in a yeast cell wall particle (YCWP) to load dendritic cells (DC) ex vivo. The tumor lysate particle loaded dendritic cell (TLPLDC) vaccine is then given to prevent melanoma recurrences. An alternate vaccine delivery method that we are evaluating utilizes the tumor lysate particle-only (TLPO) technique, in which tumor lysate is loaded into capped YCWP and injected intradermally, allowing an in vivo uptake by the patient’s dendritic cells. Methods: We are performing a prospective, random...