Plus Therapeutics Gains Momentum with Diagnostic Expansion and Clinical Progress

The oncology-focused biotechnology firm Plus Therapeutics is experiencing significant traction, driven by two distinct catalysts: major insurance coverage wins for its diagnostic platform and encouraging clinical trial updates for its therapeutic pipeline. This dual progress is strengthening the company's position within the competitive cancer care market.

Recent data presentations have highlighted the potential of the company's lead radiopharmaceutical candidate, REYOBIQ™. Detailed results shared at the San Antonio Breast Cancer Symposium on December 15 focused on breast cancer patients with leptomeningeal metastases (LM), a severe complication. Among nine evaluable patients, two demonstrated a radiological response, while four achieved stable disease. This translated to a clinical benefit rate of 67% in this subgroup.

These findings build upon earlier Phase 1 trial data from August, which reported clinical benefit rates exceeding 75% with a favorable tolerability profile. The company is now advancing patient recruitment for Phase 2 studies of REYOBIQ™, scheduled to continue through 2026.

Insurance Contracts Unlock a Multi-Billion Dollar Diagnostic Market

A pivotal commercial development for Plus Therapeutics is the execution of two national coverage agreements for its CNSide diagnostic platform. These contracts, secured by its subsidiary CNSide Diagnostics, are set to dramatically expand patient access.

Should investors sell immediately? Or is it worth buying Plus Therapeutics?

The first agreement with UnitedHealthcare, effective September 2025, provides coverage for the CNSide test to over 51 million individuals in the United States. This was followed in October by a second pivotal contract with Humana, extending the total coverage to approximately 67 million people.

These agreements represent a critical commercial milestone, as they guarantee reimbursement for the precise cerebrospinal fluid (CSF) test used in diagnosing LM. By removing a key barrier to adoption, Plus Therapeutics is paving the way for broad market penetration in an addressable market the company estimates to be worth more than $6 billion.

Strategic Execution and Forward Path

Looking ahead, Plus Therapeutics has outlined clear operational priorities. The company plans to continue scaling its laboratory capacities to support the anticipated demand for the CNSide platform. Concurrently, the clinical development of REYOBIQ™ remains a core focus, with ongoing trials designed to further validate its efficacy in treating brain tumors.

The combination of near-term commercial execution in diagnostics and mid-term therapeutic potential positions the company at an interesting inflection point, with both business segments contributing to its growth narrative.