Atossa Therapeutics (ATOS) investor relations material

Investment highlights and financial position

• $26.1M in cash and equivalents and no debt as of June 30, 2026; funded into 2027 with potential for up to $12M more from warrants.

• Disciplined capital deployment with Q2 2026 operating expenses of $8.7M, focused on regulatory pathways.

• Recent $4M raised in June 2026; opportunistic capital raising to support rare disease studies.

• Oncology is the core value driver, with rare disease programs providing additional regulatory and market opportunities.

(Z)-Endoxifen: Mechanism, Differentiation, and Pipeline

• (Z)-Endoxifen is a potent oral SERM/SERD, 30–100x more active than tamoxifen, delivered as the active metabolite for consistent exposure.

• Dual mechanism: blocks estrogen receptor signaling and promotes receptor degradation, with improved tolerability and predictable absorption.

• Targets multiple disease pathways: estrogen-driven cancers, rare diseases (MAS, DMD), and dystrophinopathies.

• Oncology pipeline includes neoadjuvant, adjuvant, and metastatic breast cancer; rare disease pipeline includes MAS and DMD, with IND clearance anticipated in 2H26.

Rare disease programs: MAS and DMD

• MAS: (Z)-Endoxifen targets estrogen-driven pathology in girls with precocious puberty, aiming to prevent irreversible loss of adult height.

• No approved therapies for MAS-PPP; current off-label agents are inadequate, leaving ER signaling incompletely blocked.

• (Z)-Endoxifen blocks both ER and PKCβ/AKT signaling, offering dual antiproliferative effects and bypassing metabolism issues seen with tamoxifen.

• Four proof points for MAS: mechanistic evidence, validated clinical target, defined regulatory path, and feasible trial execution.

• DMD: mutation-agnostic approach, acting downstream of dystrophin defects to stabilize muscle, reduce inflammation, and support cardiac function.

• Preclinical models show improved muscle function, reduced damage, and favorable safety profile.

• IND clearance for both MAS and DMD expected in 2H26, with Phase 2 trials planned for 2027.