Black Diamond Therapeutics announces results from Phase 1 trial of BDTX-1535

Black Diamond Therapeutics announced topline results from the dose escalation portion of the Phase 1 clinical trial of BDTX-1535 in patients with recurrent glioblastoma who expressed epidermal growth factor receptor (EGFR) alterations at the time of their initial diagnosis. Clinical data as of November 2023 reflect 27 patients with recurrent GBM who received a range of doses spanning 15mg to 400mg once daily in the dose escalation cohort. Combined pharmacokinetic (nd safety data from these 27 patients with GBM and 27 patients with NSCLC were previously presented on October 14, 2023 at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics. No new safety signals were observed; adverse events were consistent with the EGFR tyrosine kinase inhibitor class of drugs, including primarily Grade 1 and 2 diarrhea and rash. Key results: Of the 22 patients evaluable for efficacy, 3 patients were on therapy longer than 10 months, 1 patient longer than 6 months, and 5 patients longer than 4 months. Historical progression-free survival in this population is in the range of 2-4 months. The patient on therapy the longest remains on BDTX-1535 at 100mg QD for over 15 months with prolonged disease stabilization. This patient had previously progressed after 3 months of temozolomide treatment. Of the 19 patients with measurable disease by Response Assessment in Neuro-Oncology criteria, 1 patient achieved a confirmed partial response and 8 patients experienced stable disease. The patient with the PR stayed on treatment for longer than 4 months at 200 mg QD.