Plus Therapeutics presents updated progress from its ReSPECT-LM Phase 1 trial

Plus Therapeutics (PSTV) presented data updating the progress of its ReSPECT-LM Phase 1 clinical trial of Rhenium Obisbemeda in leptomeningeal disease (LM). The data were presented at the 2024 Society for Neuro-Oncology Annual Meeting November 21-24 in Houston, Texas. ReSPECT-LM dose escalation trial: Response: The best clinical benefit rate from a single dose of Rhenium Obisbemeda, assessed from baseline to day 112, was measured through complete response, partial response, and stable disease across three key metrics: Circulating tumor cells: 93% responded, including 1 complete response and 1 stable case, MRI imaging: 75%, with 5 responses and 7 stable cases, Clinical Response: 86%, with 2 responses and 10 stable cases; Median overall survival for Cohorts 1-4 was 9 months, with 6 out of the 16 patients alive at the time of analysis; Three of the 20 patients received up to 3 doses of Rhenium Obisbemeda under compassionate use IND, all surviving over 400 days, with one exceeding 30 months. Next steps: The first patient in Cohort 6 has been treated using a modified dose of 75 mCi; Cohort 6 is anticipated to conclude in Q1 2025; Planning is underway for a Phase 1b single dose expansion cohort trial using the Cohort 4 dose of 44 mCi, which is expected to fully enroll in 2025