Tuesday, September 12, 2023
Black Diamond Therapeutics, Inc. (Nasdaq: BDTX), a clinical-stage precision oncology company specializing in therapies targeting families of oncogenic mutations in genetically defined cancers, has announced the initiation of mutation-matched expansion cohorts within the ongoing Phase 1 clinical trial for BDTX-1535. BDTX-1535 is a fourth-generation brain-penetrant epidermal growth factor receptor (EGFR) MasterKey tyrosine kinase inhibitor (TKI) currently under investigation for treating non-small cell lung cancer (NSCLC) patients with intrinsic driver and/or acquired resistance EGFR mutations, including those who have developed resistance to osimertinib, as well as patients with glioblastoma multiforme (GBM) featuring multiple EGFR alterations.
The expansion cohort phase of the study is primarily focused on assessing the objective response rate (ORR) when BDTX-1535 is administered as a single agent in second- or third-line treatment settings for NSCLC patients harboring EGFR intrinsic driver and/or acquired resistance mutations. These patients have previously undergone treatment with approved EGFR TKIs.
The decision to initiate dosing for the first patients in the expansion cohorts comes after promising results from the dose escalation phase of the BDTX-1535 Phase 1 clinical trial, which demonstrated clinical efficacy through radiographic responses in NSCLC patients with various EGFR mutations, including intrinsic driver mutations and EGFR mutations acquired after osimertinib treatment.
Dr. Sergey Yurasov, Chief Medical Officer of Black Diamond Therapeutics, emphasized the importance of these expansion cohorts in evaluating treatment response and response duration in NSCLC patients who have experienced disease progression following prior EGFR inhibitor therapy. He also highlighted the pressing need for effective targeted therapies for EGFR mutation-positive NSCLC patients, among whom chemotherapy remains a common treatment option.
David Epstein, President and Chief Executive Officer of Black Diamond Therapeutics, underscored the potential of BDTX-1535 as a manageable alternative to chemotherapy for patients with treatment-resistant lung cancer. He also reiterated the company's commitment to advancing this innovative MasterKey inhibitor to address the genetic diversity found within the EGFR mutation-positive NSCLC patient population.
BDTX-1535 was developed using the company's Mutation-Allostery-Pharmacology (MAP) drug discovery engine, which targets families of mutations with a single drug. This approach aims to address the unmet need presented by intrinsic driver and acquired resistance EGFR mutations to osimertinib, a prevalent issue for patients with EGFR-mutant lung cancer.
The Phase 1 clinical trial (NCT05256290) of BDTX-1535 comprises a dose escalation phase, which has already been completed, and the ongoing dose expansion cohorts. It includes patients with advanced/metastatic NSCLC harboring EGFR mutations, with or without central nervous system (CNS) involvement, or with recurrent GBM expressing EGFR alterations. The study is now progressing to evaluate BDTX-1535 as a single-agent therapy in second- or third-line treatment for two cohorts of EGFR mutation-positive NSCLC patients who have experienced disease progression after prior EGFR TKI therapy, such as osimertinib. The evaluation encompasses ORR, CNS ORR, duration of response, progression-free survival, safety, tolerability, and pharmacokinetics. Additionally, the company plans to investigate the safety and efficacy of BDTX-1535 in a first-line setting for NSCLC patients with intrinsic driver EGFR mutations after discussions with the U.S. Food and Drug Administration (FDA).