RECTIFY-1: Neoadjuvant Botensilimab + Balstilimab in MSS/pMMR Early Rectal Cancer

This study is a multi-site, prospective, non-randomized, phase 2 trial. The protocol proposes to treat 16 participants with a single fixed dose of botensilimab 75 mg IV on the first day of treatment, followed by balstilimab 240 mg IV every 2 weeks for up to 6 months. The schema states that patients with stage I MSS/MMRp rectal cancer (T1-2 N0 by MRI) will undergo tumor response assessment during treatment for 6 months. After treatment, participants with complete or near complete response and pathologic complete response at local excision may undergo non-operative management with long-term surveillance, while those with residual disease or tumor progression will undergo management per standard of care. The study calendar includes treatment cycles, discontinuation, 30-day and 90-day safety follow-up, efficacy follow-up, and survival follow-up by phone every 12 weeks.