Guardant Health and Merck announced a multi‑year collaboration to use Guardant’s liquid and tissue biopsy platforms to support enrollment and biomarker stratification in Merck’s global clinical studies. The agreement covers development and commercialization pathways for companion diagnostics tied to Merck programs and may include assays across Guardant’s portfolio. Both companies framed the deal as a means to accelerate patient selection and trial efficiency for precision oncology programs.