PRTX007

This Phase 2, multi-center, single-arm study evaluates the safety, tolerability, and activity of neoadjuvant PRTX007 in combination with pembrolizumab in participants with resectable Stage III melanoma. Neoadjuvant immunotherapy has demonstrated improved clinical outcomes compared with adjuvant-only approaches, but there remains a need to enhance pathologic response rates without significant added toxicity. Participants will receive oral PRTX007, a Toll-like receptor 7 (TLR7) agonist prodrug, administered in combination with intravenous pembrolizumab prior to surgical resection. The primary objective is to determine the major pathologic response (MPR) rate following neoadjuvant therapy. Secondary objectives include evaluation of safety, pathologic complete response, event-free survival, overall survival, pharmacokinetics, and immune-related biomarkers. This study aims to determine whether the addition of PRTX007 to pembrolizumab improves antitumor immune responses and clinical outcomes in patients with Stage III melanoma.