The FDA approved Foundation Medicine’s FoundationOne CDx assays as a companion diagnostic for Pfizer’s Talzenna plus Xtandi regimen in metastatic castration-resistant prostate cancer. The coverage is tied to identifying homologous recombination repair (HRR) gene mutations, enabling patient selection for the targeted combination. The approval expands the role of tumor genomic testing in prostate cancer treatment decisions, reinforcing the CDx-centric approach for multiple targeted oncology combinations. For diagnostics companies, the decision also signals continued regulator support for analytically validated sequencing platforms paired to specific therapeutic indications.