OS Therapies (OSTX) Proxy Filing summary

Executive summary

• Over $300 million invested in the listeria immunotherapy platform, with assets acquired in April 2025 and a focus on OST-HER2 for osteosarcoma and other cancers.

• OST-HER2 has received Orphan, Fast Track, and Rare Pediatric Disease designations from FDA and EMA, with accelerated approval targeted for Q2–Q3 2026.

• The company is advancing a tunable drug conjugate (tADC) platform, with preclinical studies and Phase 1 trials for ovarian cancer expected in 2025.

• Human osteosarcoma market opportunity estimated at $1.2B, with expected US topline revenue for OST-HER2 over $500M; canine osteosarcoma TAM is $150M.

• Cash on hand projected into mid-2026, with a monthly cash burn of ~$300K and market cap around $60M.

Voting matters and shareholder proposals

• Annual meeting convened on October 14, 2025, with proposals including Issuance Proposal, Charter Amendment Proposal, and Auditor Ratification Proposal receiving requisite votes.

• Meeting adjourned to allow additional time for proxy solicitation; reconvened meeting scheduled for October 21, 2025.

• No changes to proposals; record date remains August 20, 2025.

Board of directors and corporate governance

• Management team has over 100 years of combined experience, including major product launches and expertise in oncology, virology, and strategic planning.

• Scientific advisory board includes leading clinicians and researchers in pediatric oncology and musculoskeletal oncology.