Prnewswireยท2025-07-29 11:45Core Viewpoint - Atossa Therapeutics has received positive feedback from the FDA regarding its proposed dose optimization trial for (Z)-endoxifen, aimed at treating ER+/HER2- metastatic breast cancer, which is a significant milestone for the company [1][2][3] FDA Feedback and Clinical Development - The FDA's constructive responses affirm key elements of Atossa's clinical development plan, eliminating the need for a virtual pre-IND meeting and facilitating a potential IND submission by Q4 2025 [2][3] - The FDA supports Atossa's dose optimization strategy and agrees with the existing clinical and nonclinical data, allowing the initiation of Part A (monotherapy) of the proposed study [7] Strategic Momentum and Future Plans - Atossa is positioned to maintain strategic momentum and meet regulatory milestones, aiming to deliver (Z)-endoxifen to patients and enhance shareholder value [5] - The company plans to announce details regarding the target patient population, combination therapies, and overall trial design for the upcoming dose-ranging study in the coming weeks [7] Project Optimus and Dose Exploration - The FDA's Project Optimus initiative emphasizes data-driven dose exploration to maximize benefits and minimize toxicity, which aligns with Atossa's upcoming clinical study plans [6] - Atossa will explore multiple dose levels in its study to define the optimal dose for combination therapy while ensuring a balance between efficacy and patient safety [6] (Z)-Endoxifen Overview - (Z)-endoxifen is a potent Selective Estrogen Receptor Modulator (SERM) that inhibits and potentially degrades estrogen receptors, showing activity in tumors resistant to other therapies [8] - The compound is being developed in a proprietary oral formulation that is enteric-coated to ensure optimal bioavailability and therapeutic integrity [9] Clinical Trials and Intellectual Property - Atossa is prioritizing (Z)-endoxifen for metastatic breast cancer, currently evaluating it in three Phase 2 trials [10] - The program is supported by a growing global intellectual property portfolio, including recently issued U.S. patents and pending applications worldwide [10]