Minimal residual disease (MRD) testing moved toward clinical validation in 2025 as randomized trial readouts and commercial consolidations bolstered the biomarker’s utility across oncology indications. The landmark IMvigor011 trial used Natera’s tumor-informed Signatera to select muscle-invasive bladder cancer patients for adjuvant immunotherapy and showed a survival benefit for ctDNA-positive patients receiving Tecentriq. Positive Phase III data and regulatory submissions have spurred industry consolidation and reimbursement discussions, supporting MRD’s path from an investigational marker to a clinical decision tool. Companies that secure companion-diagnostic designations and guideline inclusion will hold strategic advantages in post-surgical oncology management.