The FDA approved the first ctDNA MRD-guided adjuvant therapy in bladder cancer, authorizing Genentech’s Tecentriq and Tecentriq Hybreza for muscle-invasive disease with detectable circulating tumor DNA after cystectomy. The decision pairs Tecentriq with Natera’s Signatera CDx to identify ctDNA-positive patients, making the assay simultaneously the companion test. In the Phase III IMvigor011 trial, disease-free survival nearly doubled with Tecentriq (9.9 months vs. 4.8 months with placebo), and overall survival also improved. For clinicians and payers, the approval formalizes MRD testing as a regulatory gateway for adjuvant decision-making—potentially allowing ctDNA-negative patients to avoid treatment.