The FDA approved Guardant Health’s Guardant360 CDx as a companion diagnostic to identify BRAF V600E–mutant metastatic colorectal cancer patients for Pfizer’s encorafenib (Braftovi) plus cetuximab and chemotherapy, based on data from Pfizer’s Phase 3 BREAKWATER trial. Guardant360 provided rapid circulating tumor DNA analysis in the study and will now be an authorized blood-based route to select patients for the regimen. Guardant said the decision expands its companion-diagnostic footprint and underscores liquid biopsy utility for treatment selection and resistance monitoring in aggressive solid tumors.