Prnewswireยท2025-08-20 12:30Core Insights - Atossa Therapeutics is advancing (Z)-endoxifen into a pivotal Phase 2 dose-ranging study for metastatic breast cancer, with regulatory input from the FDA and an IND filing expected in Q4 2025, aiming for topline results in 2026 [1][3][4] Study Design and Execution - The global Phase 2 study will evaluate the safety, pharmacokinetics, pharmacodynamics, and preliminary anti-tumor activity of (Z)-endoxifen monotherapy [3][4] - PSI has been selected as the contract research organization to manage the study, recognized for its efficiency in oncology trials, with 93% of its studies enrolling on time in 2024 [4][5][6] Market Opportunity - Approximately 5.6% of newly diagnosed invasive breast cancers in the U.S. are metastatic, equating to about 13,000 women annually, with an estimated 170,000 women currently living with metastatic breast cancer [7] - Current therapies often fail due to resistance, creating a significant market opportunity for (Z)-endoxifen as a potential first-in-class therapy in this multi-billion-dollar market [7] Pipeline Development - In addition to the metastatic trial, Atossa is advancing other Phase 2 studies, including (Z)-endoxifen monotherapy in early-stage breast cancer and combination therapy with abemaciclib [8] Product Profile - (Z)-endoxifen is a potent Selective Estrogen Receptor Modulator/Degrader (SERM/D) with dual mechanisms of action, showing potential for superior bone protection and a favorable safety profile compared to tamoxifen [9][10] - The proprietary formulation of (Z)-endoxifen is designed to enhance bioavailability and overcome limitations of previous formulations [10]