Plus Therapeutics Raises $5.7M to Advance Novel Radiotherapy for Leptomeningeal Metastases
Key Insights
Plus Therapeutics secured $5.7 million in funding through a $3.7M private placement and $2.0M advance from CPRIT to support their Rhenium-186 radiotherapy development for leptomeningeal metastases (search).
The funding will accelerate the ReSPECT-LM Phase 2a trial of Rhenium (186Re) Obisbemeda and advance development of the CNSide (search) diagnostic test as a key trial endpoint.
The company is developing innovative targeted radiotherapy for CNS cancers, with their lead candidate showing potential for improved outcomes in leptomeningeal metastases (search), which currently has no FDA-approved treatments.
Plus Therapeutics has secured $5.7 million in combined financing to advance its innovative radiotherapy program for leptomeningeal metastases (search) (LM), a rare but devastating cancer complication. The funding comprises a $3.7 million private placement from existing investors and a $2.0 million advance payment from the Cancer Prevention & Research Institute of Texas (search) (CPRIT).
Strategic Funding to Accelerate Clinical Development
The new capital will primarily support the company's ReSPECT-LM Phase 2a single-dose expansion trial, evaluating Rhenium (186Re) Obisbemeda for LM treatment. Additionally, the funds will advance the development of CNSide (search), a proprietary diagnostic test crucial for trial endpoints. The $2.0 million CPRIT advance is part of an existing $17.6 million grant award, with approximately $5.2 million still remaining.
Addressing an Urgent Unmet Medical Need
Leptomeningeal metastases (search) represent a severe complication affecting approximately 5% of cancer patients, with particularly high incidence in breast cancer patients (3-5%). The condition occurs when cancer spreads to the cerebrospinal fluid and the protective layers surrounding the brain and spinal cord. Current survival rates are extremely poor, with only 7% of patients surviving one year and 3% reaching two years.
Innovative Therapeutic Approach
Rhenium (186Re) Obisbemeda represents a novel approach to treating CNS tumors, designed to deliver targeted high-dose radiation with improved safety and efficacy. The radiotherapy's unique properties include:
- Short half-life for optimal treatment duration
- Beta energy capabilities for precise tumor destruction
- Gamma energy emissions enabling real-time imaging
- Targeted delivery system to minimize off-target effects
Diagnostic Innovation: CNSide Platform
In parallel with the therapeutic development, Plus Therapeutics is advancing its CNSide (search) diagnostic platform, scheduled for commercial launch in 2025. The platform includes:
- Quantitative analysis of tumor cells in cerebrospinal fluid
- Molecular characterization capabilities
- Multiple laboratory-developed tests for diagnosis and treatment monitoring
- Integration into the ReSPECT-LM trial as an exploratory endpoint
Financial Restructuring
As part of the financing package, Plus Therapeutics has also executed a strategic exchange agreement with existing investors, issuing secured convertible promissory notes worth $3,188,922 in exchange for the cancellation of previously issued warrants. This restructuring provides additional financial flexibility for the company's development programs.