Plus Therapeutics Inc. (NASDAQ: PSTV) announced results from a health economics study indicating its CNSide cerebrospinal fluid assay may reduce healthcare costs for leptomeningeal metastases patients by approximately 33-47%.

The study, conducted with Harvard T.H. Chan School of Public Health, was presented at the ISPOR 2026 Annual Meeting in Philadelphia and received blue-ribbon recognition awarded to the top 5% of presentations. The analysis examined the economic impact of earlier detection and therapeutic management of leptomeningeal metastases using the CNSide platform.

According to the research, late-stage leptomeningeal metastases diagnosis carries substantial healthcare costs, with median inpatient admissions reaching approximately $20,000. Total monthly costs related to the condition may exceed $100,000, driven by repeated imaging, treatments, and palliative care.

The study found that earlier detection and treatment optimization enabled by CNSide could reduce overall healthcare costs by approximately 40%. These savings stem from earlier therapeutic intervention, improved treatment precision, reduced adverse events and hospitalizations, according to the company's statement.

"Health economics data are an important determinant in payer decision making and these data suggest the potential cost savings associated with earlier intervention and optimized management," said Randy Goodman, Plus Therapeutics' Vice President of Value Strategy & HEOR.

Leptomeningeal metastases affect approximately 5% of patients with metastatic cancer, with breast cancer, lung cancer, and melanoma being the most common sources. Median survival typically ranges from 2-6 months.

CNSide Diagnostics is a wholly owned subsidiary of Plus Therapeutics that develops laboratory-developed tests designed to identify tumor cells that have metastasized to the central nervous system. The analysis utilized published literature, real-world data, and healthcare claims databases to estimate costs associated with late-stage diagnosis.