- Plus Therapeutics (PSTV, Financial) achieved a 75% clinical benefit rate through neuroimaging in its Phase 1 ReSPECT-LM trial for REYOBIQ™.
- No dose-limiting toxicity was observed in the first four cohorts; a Grade 4 thrombocytopenia was noted in higher dose levels.
- RNA sequencing showed both early apoptosis and a robust immune response, suggesting REYOBIQ's dual mechanism of action.
Plus Therapeutics, Inc. (PSTV), a clinical-stage pharmaceutical company, presented new data on its REYOBIQ™ compound at the Nuclear Medicine and Neurooncology conference in Vienna. The findings from the Phase 1 ReSPECT-LM dose escalation trial demonstrate encouraging results for patients with leptomeningeal metastases.
Key results from the trial show a dose-dependent increase in absorbed radiation dose to the cranial and spinal subarachnoid space, achieving levels up to 253Gy in Cohort 5. Neuroimaging revealed a partial response in 31% of patients (5 out of 16), while the clinical benefit rate reached 75% by day 112, with 86% based on physician evaluation.
Importantly, no dose-limiting toxicity was detected in the initial four cohorts. However, Grade 4 thrombocytopenia was identified in the higher-dose Cohorts 5 and 6. RNA sequencing underscored the biological effectiveness of REYOBIQ™ by showing early induction of apoptosis, followed by innate and adaptive immune responses characterized by increased T cells by Day 28.
Plus Therapeutics aims to target central nervous system (CNS) cancers with its advanced radiotherapeutic technology, creating promising pathways for treating challenging conditions like leptomeningeal metastases. CEO Marc H. Hedrick, M.D., expressed optimism about REYOBIQ’s potential to improve patient outcomes, emphasizing its ability to deliver high doses of targeted radiation safely.
Leptomeningeal Metastases (LM) remains a rare but severe complication of cancer, often seen in cases where solid tumors metastasize to cerebrospinal fluid. The condition has limited treatment options and a generally poor prognosis, highlighting the significant need for effective therapies like REYOBIQ™.
