Boundless Bio (BOLD) Piper Sandler 36th Annual Healthcare Conference summary

Company overview and scientific focus

• Focuses on precision oncology for patients with oncogene amplifications, representing about 25% of all cancer patients.

• Only biopharma company dedicated to targeting oncogene amplifications via extrachromosomal DNA (ecDNA).

• Identified multiple novel targets and has several clinical programs with near-term catalysts expected in the next 12 months.

Scientific rationale and platform

• Traditional targeted therapies are ineffective for oncogene amplifications due to the dynamic nature of ecDNA.

• ecDNA are circular, cancer-specific DNA units that drive rapid gene amplification and heterogeneity, leading to therapy resistance.

• The Spyglass platform was developed to map the ecDNA life cycle and identify intervention points unique to cancer cells.

Lead program: BBI-355 (CHK1 inhibitor)

• CHK1 is a synthetic lethal target due to cancer cells’ reliance on DNA damage response from ecDNA-induced replication stress.

• BBI-355 is optimized for potency, selectivity, and oral bioavailability, with a biomarker-driven approach to patient selection.

• Monotherapy shows good PK/PD, manageable and reversible hematologic toxicity, and a well-tolerated dosing schedule.