BlossomHill Therapeutics (BLSM) H.C. Wainwright 28th Annual Global Investment Conference summary

Company overview and scientific approach

• Founded in June 2020 to address high unmet medical needs through chemistry innovation, focusing on structure-based design and protein dynamics for drug development.

• Built a strong leadership team and advanced two macrocyclic molecules into clinical trials, with a third in IND-enabling studies.

• Pipeline includes an EGFR inhibitor, a CLK inhibitor, and a pan-KRAS inhibitor, each designed to overcome resistance and improve efficacy.

Lead asset (BH-30643) clinical data and differentiation

• Presented updated phase I data at WCLC 2026 for C797S-resistant patients: 45% objective response rate, 88% disease control rate, and durable responses with some patients on treatment beyond one year.

• Demonstrated high brain penetration and efficacy in patients with brain metastases; ORR was 53% without chemotherapy and 38% with chemotherapy.

• Safety profile showed low rates of dose reduction (9%) and discontinuation (3%), with most adverse events being mild; main AE was bilirubin increase due to UGT1A1 inhibition.

• Molecule is tenfold more potent than osimertinib, with broad activity against primary and resistant EGFR mutations and a favorable selectivity window.

Competitive landscape and pipeline strategy

• BH-30643 is positioned as more potent and broadly active than competitors from Hansoh Pharma, Daiichi Sankyo, and Voronoi, particularly in overcoming T790M and C797S resistance.

• Pan-KRAS inhibitor (BH-501284) uses a novel Switch-II pocket design for pseudo-irreversible inhibition, aiming for deeper and longer signaling shutdown compared to tri-complex molecules.

• Internal combination strategies focus on synergy between CLK and KRAS or EGFR inhibitors, with preclinical data showing promising results; further data expected at AACR next year.