Molecular diagnostics company BillionToOne reported Q4 revenue that more than doubled year‑over‑year and raised full‑year 2026 guidance. Management cited new payer contracts — notably an in‑network agreement with UnitedHealthcare effective April 1 — expanded test volumes and recent product launches as drivers. The firm also plans salesforce expansion across prenatal and oncology channels and pursues additional payer coverage (MolDx) for a therapy‑response assay. Financial momentum and insurer access aim to raise average selling price and patient reach for its prenatal and oncology NIPT and other molecular tests.