The FDA approved Genentech’s Tecentriq (atezolizumab) and Tecentriq Hybreza (atezolizumab plus hyaluronidase-tqjs) as adjuvant treatment for muscle-invasive bladder cancer patients with circulating tumor DNA after cystectomy, using Natera’s Signatera CDx assay to select patients. In the Phase 3 IMvigor011 trial, 250 patients who were ctDNA-positive by Signatera and had no radiographic disease were randomized to Tecentriq or placebo. Disease-free survival nearly doubled with Tecentriq (9.9 months vs. 4.8). Overall survival also improved (32.8 months vs. 21.1), with 62.8% alive at two years on Tecentriq compared with 46.9% on placebo. The approval is described as the first for an MRD-guided therapy in the US, and Signatera was authorized simultaneously as a CDx for identifying ctDNA-positive patients likely to benefit. Patients who test negative on Signatera were reported to have 97% survival at two years without adjuvant treatment, supporting MRD-guided treatment de-escalation. Genentech framed the decision as a milestone for precision medicine, positioning ctDNA-guided selection as a way to reduce unnecessary post-cystectomy immunotherapy.