On February 26, 2025 Plus Therapeutics, Inc. (Nasdaq: PSTV) (the "Company" or "Plus Therapeutics"), a clinical-stage pharmaceutical company developing targeted radiotherapeutics with advanced platform technologies for central nervous system (CNS) cancers, reported the completion of the ReSPECT-LM Phase 1 single-dose escalation trial, having determined an RP2D (Press release, Plus Therapeutics, FEB 26, 2025, View Source [SID1234650646]).
Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:
Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing
Schedule Your 30 min Free Demo!
The ReSPECT-LM single-dose escalation trial assessed the safety, tolerability, and potential efficacy of intrathecally administered Rhenium (186Re) Obisbemeda in patients with leptomeningeal metastases (LM). Enrollment in Cohort 6 was recently completed (75.0 mCi). The Cohort 4 dose (44.1 mCi) was determined to be the RP2D; no dose-limiting toxicities were observed at this dose level. One patient at the Cohort 4 dose was observed to have achieved a complete response, as evidenced by the eradication of tumor cells in the cerebrospinal fluid—a key therapeutic endpoint.
"With the RP2D established, we are advancing both a single dose-expansion Phase 2 trial and a multiple-dose Phase 1 trial of 44.1 mCi fractionated into three doses to further assess safety and efficacy," said Marc H. Hedrick, M.D., Plus Therapeutics President and Chief Executive Officer. "We remain on track to complete enrollment in both trials this year and are simultaneously engaging the U.S. Food & Drug Administration to define the optimal pivotal trial pathway."
Additional details on the ReSPECT-LM trial can be found here.
About Leptomeningeal Metastases (LM)
LM is a rare complication of cancer in which the primary cancer spreads to the cerebrospinal fluid (CSF) and leptomeninges surrounding the brain and spinal cord. All malignancies originating from solid tumors, primary brain tumors, or hematological malignancies have this LM complication potential with breast cancer as the most common cancer linked to LM, with 3-5% of breast cancer patients developing LM. Additionally, lung cancer, GI cancers and melanoma can also spread to the CSF and result in LM. LM occurs in approximately 5% of people with cancer and is usually terminal with 1-year and 2-year survival of just 7% and 3%, respectively. The incidence of LM is on the rise, partly because cancer patients are living longer and partly because many standard chemotherapies cannot reach sufficient concentrations in the spinal fluid to kill the tumor cells, yet there are no FDA-approved therapies specifically for LM patients, who often succumb to this complication within weeks to several months, if untreated.