Atossa Therapeutics Receives FDA Approval to Proceed with Breast Cancer Study
Atossa Therapeutics announced that the U.S. FDA issued a "Study May Proceed" letter for the company's study in metastatic breast cancer which was the subject of a recent investigational new drug application for (Z)-endoxifen. "This letter marks an important regulatory milestone for Atossa and to potentially expand the use of (Z)-endoxifen for metastatic ER+/HER2- Breast Cancer. We believe its activity, even in tumors that have developed resistance to other endocrine therapies and in the oncogenic signaling pathway, protein kinase C beta 1, may offer a new tool in treating this disease.," said Dr. Steven Quay, M.D., Ph.D., Atossa Therapeutics President and CEO. "We appreciate the FDA's review and look forward to advancing this clinical investigation."
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- PRV Program Reauthorization: The U.S. Congress has passed a five-year reauthorization of the Rare Pediatric Disease Priority Review Voucher (PRV) program, enabling Atossa to qualify for a future PRV upon FDA approval, signaling strong support for the drug development industry.
- Potential of (Z)-endoxifen: Atossa's (Z)-endoxifen has received Rare Pediatric Disease (RPD) designation for treating Duchenne Muscular Dystrophy (DMD), providing new opportunities for the company in both cancer and rare diseases, potentially leading to non-dilutive value creation.
- Strong Market Demand: DMD is a fatal childhood disease, and families urgently need treatment options beyond steroids and gene-targeted therapies; the development of (Z)-endoxifen aims to offer a broader treatment approach to meet significant unmet medical needs.
- Positive Preclinical Data: Atossa is optimistic about the emerging preclinical data for (Z)-endoxifen and plans to advance it to clinical trials, aiming to provide more effective treatment options for DMD patients and further solidify the company's market position in the biopharmaceutical sector.

- Leadership Recognition: Atossa Therapeutics' Founder and CEO Steven Quay has been named one of the Top 50 Healthcare Technology CEOs of 2025, highlighting his exceptional leadership in biotechnology innovation and team building, which enhances the company's reputation in the industry.
- Precision Therapy Advancement: Under Quay's leadership, Atossa's lead product (Z)-endoxifen is being optimized across multiple Phase 2 clinical trials, aiming to provide consistent systemic treatment for breast cancer patients, which is expected to significantly improve patient outcomes.
- Multiple Indication Exploration: The company is exploring the application of (Z)-endoxifen for Duchenne Muscular Dystrophy (DMD), which, if successful, will further expand its market potential and strengthen the company's competitiveness in the rare disease sector.
- Strategic Investment Focus: Atossa emphasizes a disciplined capital allocation strategy in clinical development, concentrating on projects that can support future regulatory submissions and commercialization, ensuring sustainable growth in the biopharmaceutical industry.

- Leadership Recognition: Atossa Therapeutics' Founder and CEO Steven Quay has been named one of the Top 50 Healthcare Technology CEOs of 2025, highlighting his exceptional leadership in advancing biotechnology innovation and building a high-performing, people-centered organization.
- Precision Therapy Advancement: Under Quay's guidance, Atossa's lead product (Z)-endoxifen is being optimized across multiple Phase 2 clinical trials, aiming to provide a unique selective estrogen receptor modulator/degrader that significantly enhances breast cancer treatment outcomes.
- Exploration of Multiple Indications: Atossa is also investigating the application of (Z)-endoxifen for Duchenne Muscular Dystrophy (DMD), showcasing its potential to address high unmet clinical needs and potentially open new market opportunities for the company.
- Strategic Investment Focus: The company emphasizes disciplined capital allocation in clinical development, concentrating on projects that can support future regulatory submissions and commercialization, ensuring sustained competitiveness and innovation in the biopharmaceutical sector.

- FDA Orphan Drug Designation: Atossa Therapeutics (ATOS) announced that its (Z)-endoxifen received Orphan Drug Designation from the FDA, leading to a 12.98% stock increase to $0.69, marking a significant milestone in the treatment of Duchenne muscular dystrophy and expected to drive future R&D progress.
- Clinical Trial Progress: ImmunityBio (IBRX) reported that over 85% of the study population has been enrolled in its registrational trial QUILT-2.005 for BCG-naïve non-muscle-invasive bladder cancer, with stock rising 9.43% to $6.04, and full enrollment anticipated by Q2 2026, enhancing market confidence.
- NASDAQ Compliance Extension: Femasys (FEMY) received NASDAQ approval for a 180-day extension to meet the minimum $1.00 bid price requirement, with stock climbing 10.68% to $0.72, providing the company until July 13, 2026, to regain compliance, alleviating investor concerns.
- Successful Financing: Foghorn Therapeutics (FHTX) closed a $50 million registered direct financing at a 30% premium, resulting in a 4.02% stock increase to $6.26, demonstrating market confidence and support for its future development.

- Orphan Drug Designation: Atossa Therapeutics' (Z)-endoxifen has received FDA Orphan Drug Designation for treating Duchenne muscular dystrophy (DMD), indicating the drug's significance in rare disease treatment and potentially accelerating its clinical development process.
- Regulatory Incentives: This designation provides Atossa with crucial regulatory incentives to support the development of therapies in the rare disease sector, further underscoring the drug's potential to address unmet medical needs for DMD patients.
- Stock Performance: Atossa closed Friday's regular trading session at $0.6150, up 6.02% from the previous day, reflecting positive market sentiment regarding its new drug development prospects.
- After-Hours Trading Surge: In after-hours trading, Atossa's stock rose further to $0.6948, a gain of 12.98%, indicating investor optimism following the FDA designation announcement.

- Orphan Drug Designation: Atossa Therapeutics' (Z)-Endoxifen has received Orphan Drug Designation from the FDA, marking a significant advancement in the treatment of Duchenne Muscular Dystrophy (DMD) and is expected to accelerate clinical development while enhancing market competitiveness.
- Support for Rare Pediatric Diseases: This designation complements the previously received Rare Pediatric Disease designation, demonstrating Atossa's commitment to addressing the unmet medical needs of DMD patients, which may attract more investment and collaboration opportunities.
- Market Exclusivity Potential: The Orphan Drug Designation provides Atossa with potential eligibility for a period of market exclusivity upon approval, which could help the company secure a favorable position in the competitive biopharmaceutical market and drive revenue growth.
- Advancement of R&D Strategy: Atossa plans to continue engaging with the FDA to advance the development of (Z)-Endoxifen, which is expected to lay the groundwork for future clinical trials and market promotion, thereby enhancing its influence in oncology and rare diseases.






