HOUSTON, April 23, 2026 (GLOBE NEWSWIRE) -- Plus Therapeutics, Inc. (NASDAQ:PSTV) ("Plus" or the "Company"), a healthcare company developing and commercializing precision diagnostics and radiopharmaceuticals for central nervous system (CNS) cancers, announced today the initiation of manufacturing activities and technology transfer with SpectronRx under a previously executed Master Services Agreement (MSA), in support of late-stage clinical manufacturing of Rhenium-186 and REYOBIQ. With SpectronRx serving as a second GMP manufacturing site alongside Radiomedix, and Rhenium-186 isotope supplied through Telix Pharmaceuticals, Plus strengthens the reliability of its multi-partner supply chain infrastructure.

The MSA includes the technology transfer of the REYOBIQ manufacturing process, Rhenium-186 isotope processing, analytical methods, as well as technical and regulatory expertise supporting future commercial scale production. The SpectronRx's facility in Indiana will provide on-demand manufacturing capabilities for both Rhenium-186 isotope production and REYOBIQ drug manufacturing within the same facility, improving coordination across the radiopharmaceutical production process and simplifying logistics.

"We are focused on advancing our REYOBIQ development, including progress towards our 2026 target milestone to complete manufacturing scale-up for REYOBIQ late-stage clinical supply needs," said Marc H. Hedrick, M.D., Plus Therapeutics President and Chief Executive Officer. "As we enter late-stage development of REYOBIQ, our partnership with SpectronRx bolsters our manufacturing readiness and required expansion of our production capacity. We are closely aligned with SpectronRx for best-in-class production of REYOBIQ to serve the needs of the clinical community and drive growth in our radiotherapeutic business over time."

"Radiopharmaceutical development increasingly depends on infrastructure that can reliably scale alongside clinical and commercial demand," said John Zehner, SpectronRx Chief Executive Officer. "Our integrated platform, spanning isotope processing, GMP manufacturing, and regulatory expertise, is purpose-built to support partners like Plus Therapeutics as they advance late-stage programs such as REYOBIQ. We are proud to play a role in strengthening a multi-partner supply chain designed to deliver consistent, high-quality product to patients."

About REYOBIQ™ (rhenium Re186 obisbemeda)

REYOBIQ (rhenium Re186 obisbemeda) is a novel injectable radiotherapy specifically formulated to deliver direct targeted high dose radiation in CNS tumors in a safe, effective, and convenient manner to optimize patient outcomes. REYOBIQ has the potential to reduce off target risks and improve outcomes for CNS cancer patients, versus currently approved therapies, with a more targeted and potent radiation dose. Rhenium-186 is an ideal radioisotope for CNS therapeutic applications due to its short half-life, beta energy for destroying cancerous tissue, and gamma energy for real-time imaging. REYOBIQ is being evaluated for the treatment of recurrent glioblastoma, leptomeningeal metastases, and pediatric brain cancer in the ReSPECT-GBM, ReSPECT-LM, and ReSPECT-PBC clinical trials. ReSPECT-GBM is supported by an award from the National Cancer Institute (NCI), part of the U.S. National Institutes of Health (NIH), and ReSPECT-LM is funded by a three-year $17.6M grant by the Cancer Prevention & Research Institute of Texas (CPRIT). The Company's ReSPECT-PBC clinical trial for pediatric brain cancer is supported by a $3 million grant from the U.S. Department of Defense's Peer Reviewed Cancer Research Program.

About CNSide Diagnostics, LLC

CNSide Diagnostics, LLC is a wholly owned subsidiary of Plus Therapeutics, Inc. that develops and commercializes proprietary laboratory-developed tests, such as CNSide®, designed to identify tumor cells that have metastasized to the central nervous system in patients with carcinomas and melanomas. The CNSide® CSF Assay Platform enables quantitative analysis of the cerebrospinal fluid that informs and improves the management of patients with leptomeningeal metastases.

About Plus Therapeutics

Headquartered in Houston, Texas, Plus Therapeutics, Inc. is a clinical-stage pharmaceutical company developing targeted radiotherapeutics for difficult-to-treat cancers of the central nervous system with the potential to enhance clinical outcomes. Combining image-guided local beta radiation and targeted drug delivery approaches, the Company is advancing a pipeline of product candidates with lead programs in leptomeningeal metastases (LM) and recurrent glioblastoma (GBM). The Company has built a supply chain through strategic partnerships that enable the development, manufacturing, and future potential commercialization of its products.

About SpectronRx

SpectronRx is a diagnostic and therapeutic radiopharmaceutical developer and manufacturer specializing in Radiopharmaceutical Contract Development (CDMO), Manufacturing (CMO) and Isotope Production. The company supports all stages of development, from early conjugations through scale-up and commercial distribution and has the capacity to run clinical trials.

With a team of experienced radiochemists, radiopharmacists, scientists and engineers, dozens of qualified clean rooms and more than 400,000 square feet of production space, SpectronRx supplies radiopharmaceuticals to 6 continents. The company has been EMA and FDA inspected and can produce or procure any currently used radioisotope. For more information, visit SpectronRx.com or follow the company on LinkedIn.

Forward-Looking Statements

This press release contains statements that may be deemed "forward-looking statements" within the meaning of U.S. securities laws. All statements in this press release other than statements of historical fact are forward-looking statements. These forward-looking statements may be identified by future verbs, as well as terms such as "expect," "anticipate" "intend," "believe," "estimate," "will," and similar expressions or the negatives thereof. Such statements are based upon certain assumptions and assessments made by management in light of their experience and their perception of historical trends, current conditions, expected future developments and other factors they believe to be appropriate. The forward-looking statements included in this press release could differ materially from those expressed or implied by these forward-looking statements because of risks, uncertainties, and other factors that include, but are not limited to, the following: the Company's ability to successfully raise sufficient capital on reasonable terms or at all; available cash on hand and contractual and statutory limitations that could impair our ability to pay future dividends; our ability to complete our pre-clinical or clinical studies; and changes in local or national economic conditions. This list of risks, uncertainties, and other factors is not complete. Any or all forward-looking statements the Company makes may turn out to be wrong and can be affected by inaccurate assumptions the Company might make or by known or unknown risks, uncertainties, and other factors, including those identified in this press release. This list of risks, uncertainties, and other factors is not complete. Plus Therapeutics discusses some of these matters more fully, as well as certain risk factors that could affect Plus Therapeutics' business, financial condition, results of operations, and prospects, in its reports filed with the SEC, including Plus Therapeutics' annual report on Form 10-K for the fiscal year ended December 31, 2025, quarterly reports on Form 10-Q, and current reports on Form 8-K. These filings are available for review through the SEC's website at www.sec.gov. Any or all forward-looking statements Plus Therapeutics makes may turn out to be wrong and can be affected by inaccurate assumptions Plus Therapeutics might make or by known or unknown risks, uncertainties, and other factors, including those identified in this press release. Accordingly, you should not place undue reliance on the forward-looking statements made in this press release, which speak only as of its date. There may be events in the future that the Company is unable to predict, or over which it has no control, and its business, financial condition, results of operations and prospects may change in the future. The Company assumes no responsibility to update or revise any forward-looking statements to reflect events, trends or circumstances after the date they are made unless the Company has an obligation under U.S. federal securities laws to do so.

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Plus Therapeutics Initiates Manufacturing Activities with SpectronRx Under a Master Services Agreement to Support GMP Pivotal Trial Readiness for REYOBIQ™