HOUSTON, Texas — May 7, 2026 — Leads & Copy — Plus Therapeutics, Inc. announced that its subsidiary, CNSide Diagnostics, LLC, has been enrolled in the Medicare program and received a Provider Transaction Access Number (PTAN) from the Centers for Medicare & Medicaid Services (CMS).
This allows CNSide Diagnostics to submit claims for its CNSide® Cerebrospinal Fluid (CSF) Assay Platform, including the tumor cell enumeration (TCE) test. Claims will be reimbursed when considered reasonable and necessary by the Medicare Administrative Contractor (MAC).
According to Russ Havranek, EVP Corporate and Commercial Strategy, Medicare enrollment marks a step in the company’s commercialization strategy. He said it allows access to approximately half of the U.S. Medicare population through Traditional Medicare, pending coverage determinations, and creates a path to expand into Medicare Advantage populations.
The enrollment is designed to expand billing of Traditional Medicare, positioning CNSide Diagnostics to pursue coverage with Medicare Advantage plans such as those administered by United Healthcare, Humana, Highmark, and Blue Shield of California. It is also designed to accelerate coverage and pricing efforts and provide credentialing for state-by-state Medicaid enrollment.
CNSide Diagnostics is now focused on engagement with MACs to secure coverage determinations and establishment of a payment rate for the new CPT code 0640U (CNSide CSF TCE Test), effective for billing July 1, 2026, via crosswalk or gapfill methodology. It is also focused on continued execution of national and regional payer contracts toward the 2026 goal of 150 million+ covered lives.
The CNSide® CSF Assay Platform detects and characterizes tumor cells and circulating tumor DNA in cerebrospinal fluid, enabling earlier and more accurate diagnosis, disease monitoring, and treatment decision-making for patients with leptomeningeal metastases. This is a complication of CNS cancers where methods like MRI and cytology often fail.
With Medicare enrollment complete, CNSide Diagnostics is implementing a commercialization strategy to drive clinical adoption through payer coverage expansion, generating real-world data to demonstrate improved patient outcomes and cost-effectiveness, deepening relationships with academic medical centers and oncology networks, and refining coding, billing, and collections processes.
CNSide Diagnostics, LLC, based in Houston, Texas, develops and commercializes laboratory-developed tests, such as CNSide®, to identify tumor cells that have metastasized to the central nervous system in patients with carcinomas and melanomas. Plus Therapeutics, Inc. is a clinical-stage pharmaceutical company developing targeted radiotherapeutics for difficult-to-treat cancers of the central nervous system.
Source: Plus Therapeutics
