Atossa Therapeutics (ATOS) Q4 2025 earnings summary

Executive summary

• Advanced (Z)-endoxifen development in oncology and rare diseases, securing FDA Rare Pediatric Disease and Orphan Drug designations for Duchenne Muscular Dystrophy (DMD).

• Strengthened clinical leadership with new medical directors for breast oncology and rare diseases.

• Won the 2025 Clinical Trials Arena Research and Development Excellence Award in Precision Endocrine Therapy.

Financial highlights

• Total operating expenses rose to $37.1 million for 2025, up $9.5 million from 2024.

• Research and development expenses increased 50% year-over-year to $21.2 million, driven by higher clinical trial and regulatory costs for (Z)-endoxifen.

• General and administrative expenses grew 18% to $16.0 million, mainly due to higher legal and investor relations costs.

• Interest income decreased to $2.4 million from $4.1 million year-over-year due to lower average invested funds.

• Net loss widened to $34.8 million in 2025 from $25.5 million in 2024; net loss per share was $(4.04) versus $(3.04) year-over-year.

Outlook and guidance

• Plans to advance (Z)-endoxifen in both breast cancer and rare disease indications, with a focus on DMD and McCune-Albright Syndrome.

• Anticipates leveraging FDA designations for expedited review and potential financial benefits, including eligibility for a Priority Review Voucher.