Black Diamond Therapeutics Announces Initial Dose Escalation Data Demonstrating Anti-Tumor Activity of BDTX-1535 in Non-Small Cell Lung Cancer Patients Across Multiple EGFR Mutation Families

• BDTX-1535, an epidermal growth factor receptor (EGFR) MasterKey inhibitor, demonstrates clinical proof of activity for MasterKey mutation-targeting approach based on radiographic tumor responses and circulating tumor DNA changes in NSCLC patients with acquired resistance and intrinsic driver EGFR mutations

• Confirmed radiographic partial response by RECIST 1.1 achieved across predicted therapeutic doses in 5 of 12 NSCLC patients in subgroup with measurable disease, who underwent post baseline tumor assessment by RECIST1.1; one additional patient demonstrated unconfirmed PR awaiting confirmation, while the remaining six patients had stable disease
• Expansion cohorts expected to commence in second half of 2023 to assess ORR by RECIST 1.1 in NSCLC patients with EGFR-acquired resistance and intrinsic driver mutations after progression on a third-generation EGFR inhibitor
• Favorable tolerability profile observed with once-daily therapeutic doses to be further explored in NSCLC expansion cohorts
• Update on Phase 1 dose escalation data in GBM cohort anticipated in the fourth quarter of 2023
• Company to host investor conference call and webcast today at 8:00 a.m. ET

CAMBRIDGE, Mass. and NEW YORK, June 27, 2023 (GLOBE NEWSWIRE) -- Black Diamond Therapeutics, Inc. (Nasdaq: BDTX), a clinical-stage precision oncology company developing MasterKey therapies that target families of oncogenic mutations in patients with genetically defined cancers, today announced initial clinical data from the dose escalation portion of the Phase 1 clinical study of BDTX-1535. BDTX-1535 is an investigational fourth-generation epidermal growth factor receptor (EGFR) MasterKey inhibitor being developed for the treatment of non-small cell lung cancer (NSCLC) and glioblastoma multiforme (GBM). The new data from the dose escalation portion of the Phase 1 study demonstrated clinical proof of activity of BDTX-1535 in NSCLC patients harboring both acquired resistance and intrinsic driver EGFR mutations.

“These initial safety and clinical activity data support the continued development of BDTX-1535 as a potential first and best-in-class treatment option for osimertinib-resistant NSCLC patients. Importantly, BDTX-1535 is the first EGFR TKI to show radiographic responses across NSCLC patients whose cancers are driven by diverse mutation families including acquired resistance mutations after osimertinib therapy, as well as in patients whose cancers are driven by classical and intrinsic driver mutations, providing clinical validation for our MasterKey approach of targeting families of mutations with a single drug,” said Sergey Yurasov, M.D., Ph.D., Chief Medical Officer of Black Diamond Therapeutics. “With a favorable tolerability profile in dose escalation, a long half-life to support once-daily dosing and ease of administration, we believe that BDTX-1535 has the potential to become an important treatment option for patients suffering from EGFR-mutated NSCLC. With these data in hand, we look forward to working with the FDA to define our recommended Phase 2 dose selection strategy and, ultimately, discussing a path to potential accelerated approval in NSCLC patients with newly diagnosed and recurrent intrinsic and acquired resistance EGFR mutations.”