Atossa Therapeutics Regains Compliance with Nasdaq Minimum Bid Price Listing Requirements

SEATTLE, March 18, 2024 (GLOBE NEWSWIRE) -- Atossa Therapeutics, Inc. (Nasdaq: ATOS) (“Atossa” or the “Company”), today announced that on March 15, 2024, the Company received written notice from the Listing Qualifications Department of The Nasdaq Stock Market LLC (“Nasdaq”) that the Company has regained compliance with the minimum closing bid price requirement under Nasdaq Listing Rule 5550(a)(2). Atossa is a clinical stage biopharmaceutical company developing innovative medicines in areas of significant unmet medical need in oncology, with a focus on using (Z)-endoxifen to prevent and treat breast cancer.

As previously disclosed, on September 26, 2023, the Company was notified by Nasdaq that it was not in compliance with Nasdaq Listing Rule 5550(a)(2) because its common stock failed to maintain a minimum closing bid price of $1.00 per share for 30 consecutive business days. To regain compliance, the Company was required to maintain a minimum closing bid price of $1.00 per share for at least 10 consecutive trading days. This requirement was met on March 14, 2024.

About (Z)-Endoxifen
(Z)-endoxifen is the most active metabolite of the FDA approved Selective Estrogen Receptor Modulator (SERM), tamoxifen. Studies 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. (Z)-endoxifen also appears to deliver similar or even greater bone agonistic effects while resulting in little or no endometrial proliferative effects compared with tamoxifen.

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. (Z)-endoxifen is currently being studied in four Phase 2 trials: one in healthy women with measurable breast density, one in women diagnosed with ductal carcinoma in situ, 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.