Black Diamond Therapeutics (BDTX) investor relations material

Program and clinical data highlights

• Lead program silevertinib is a fourth-generation EGFR inhibitor in phase II for non-small cell lung cancer and glioblastoma, showing promising efficacy and CNS activity.

• In the U.S., about 10,000 patients annually have non-classical EGFR mutations, representing 25% of the EGFR-mutant NSCLC market, with worse outcomes than classical mutations.

• Preliminary median PFS in the frontline setting is 15.2 months, exceeding historical outcomes (6–11 months) for current therapies in non-classical mutations.

• Objective response rate is 60% across 43 patients with 33 distinct non-classical mutations, with consistent efficacy across mutation subtypes.

• 86% CNS response rate observed, with no patients developing new brain metastases during therapy, highlighting strong CNS penetration.

Safety and dosing insights

• Dose reductions from 200 mg to 150 mg (and some to 100 mg) did not compromise response depth or durability; over half of patients remain on therapy.

• Drug shows dose-linear pharmacokinetics, supporting efficacy and safety at 150 mg, with fewer dose interruptions expected.

• Grade 3 or higher adverse events declined to 28% after dose reduction, mainly EGFR-mediated (rash, diarrhea), with no QTc or liver signals.

• Discontinuation rate due to AEs was 14%, mostly early and EGFR-mediated.

Regulatory and development strategy

• Planning FDA meeting in Q3 2024 to discuss pivotal development, aiming for fastest approval path by focusing on high unmet need populations (CNS disease, PACC mutations).

• Potential for streamlined pivotal trials, possibly smaller and faster than comparator studies due to broad mutation coverage and CNS activity.

• Positive feedback from KOLs and investigators at ASCO supports rapid development and approval strategies.