Atossa Therapeutics Granted Additional Patent Protection for Endoxifen

SEATTLE, June 21, 2023 (GLOBE NEWSWIRE) — Atossa Therapeutics, Inc. (Nasdaq: ATOS), a clinical stage biopharmaceutical company developing innovative proprietary medicines to address significant unmet needs in oncology with a focus on breast cancer, today announces that the United States Patent and Trademark Office (USPTO) has granted a new patent (No. 11,680,036) directed to enterically encapsulated endoxifen compositions formulated as a suspension. These include all liquid suspension formulations suitable for oral administration and dispersible tablets, powders, granules, pellets or sprinkles for reconstitution, which are commonly used for pediatric administration. A short video explaining the new patent can be found here: Suspension Patent Update.

A suspension is a heterogeneous mixture. It differs from a solution, which is a homogeneous mixture, in that the particles in a solution are much smaller and are dissolved in a solvent, therefore staying mixed together. In a suspension, the particles are large, do not dissolve, and will separate. Advantages of suspension formulations may include ease of delivery of low soluble therapeutic agents, increased bioavailability of drug dosage, controlled drug delivery and resistance to degradation.

“Our new patent covering suspension formulations is important as we continue to learn more about the potential therapeutic role of endoxifen beyond breast cancer and mammographic breast density,” said Dr. Steven Quay, Atossa’s President and Chief Executive Officer. “Suspension formulations are particularly useful in pediatric applications where drugs are often dosed by weight and delivered via powders or sprinkles mixed with food and dispersible tablets, which are easier for children to ingest compared to tablets.”

About (Z)-Endoxifen
(Z)-endoxifen is the most active metabolite of the FDA approved Selective Estrogen Receptor Modulator (SERM), tamoxifen. Studies by others have demonstrated that the therapeutic effects of tamoxifen are driven in a concentration-dependent manner by (Z)-endoxifen. In addition to its potent anti-estrogen effects, (Z)-endoxifen at higher concentrations has been shown to target PKCβ1, a known oncogenic protein.

Atossa is developing a proprietary oral formulation of (Z)-endoxifen that does not require liver metabolism to achieve therapeutic concentrations and is encapsulated to bypass the stomach as acidic conditions in the stomach convert a greater proportion of (Z)-endoxifen to the inactive (E)-endoxifen. Atossa’s (Z)-endoxifen has been shown to be well tolerated in Phase 1 studies and in a small Phase 2 study of women with breast cancer. The Company is currently studying (Z)-endoxifen in three Phase 2 studies: one in healthy women with measurable breast density and two other studies including the EVANGELINE study in women with ER+/HER2- breast cancer. Atossa’s (Z)-endoxifen is protected by three issued U.S. patents and numerous pending patent applications.

About Atossa Therapeutics
Atossa Therapeutics, Inc. is a clinical-stage biopharmaceutical company developing innovative medicines in areas of significant unmet medical need in oncology with a focus on breast cancer. For more information, please visit www.atossatherapeutics.com

CONTACT:
Eric Van Zanten
VP, Investor and Public Relations
610-529-6219
eric.vanzanten@atossainc.com

FORWARD LOOKING STATEMENTS
Forward-looking statements in this press release, which Atossa undertakes no obligation to update, are subject to risks and uncertainties that may cause actual results to differ materially from the anticipated or estimated future results, including the risks and uncertainties associated with any variation between interim and final clinical results, actions and inactions by the FDA, the outcome or timing of regulatory approvals needed by Atossa including those needed to commence studies of (Z)-endoxifen, lower than anticipated rate of patient enrollment, estimated market size of drugs under development, the safety and efficacy of Atossa’s products, performance of clinical research organizations and investigators, obstacles resulting from proprietary rights held by others such as patent rights, whether reduction in breast density or in Ki-67 or any other result from a neoadjuvant study is an approvable endpoint for (Z)-endoxifen, whether Atossa can complete acquisitions, and other risks detailed from time to time in Atossa’s filings with the Securities and Exchange Commission, including without limitation its periodic reports on Form 10-K and 10-Q, each as amended and supplemented from time to time.