AB Science provides a summary of the webcast held on December 16, 2024

Core Viewpoint - AB Science provides an update on its AB8939 program, a novel microtubule destabilizer and ALDH inhibitor, currently in Phase 1 trials for treating acute myeloid leukemia (AML) [2]. Group 1: Product Profile and Mechanism - AB8939 is a next-generation synthetic microtubule destabilizer and stem cell-targeted ALDH1/2 inhibitor, designed for refractory/relapsing AML treatment [3]. - The drug destabilizes microtubules and is not affected by multidrug resistance mechanisms, as it does not bind to PgP and is not degraded by myeloperoxidase [4]. - AB8939 inhibits ALDH1/2, promoting the repopulation of normal progenitors in the bone marrow [5]. Group 2: Clinical Efficacy and Market Potential - AB8939 demonstrates activity across refractory AML cell lines and shows an additive effect when combined with first-line treatments like cytarabine, azacitidine, and venetoclax [6]. - The drug has potential efficacy in AML with MECOM gene rearrangement, a patient subset known for extreme resistance to chemotherapy and poor survival prognosis [7]. - The addressable market for AB8939 in relapsed/refractory AML is estimated to exceed EUR 2 billion annually [7]. Group 3: Market Size Data - In the USA and Canada, there are approximately 23,700 incidence cases of AML, with a 50% relapse or refractory rate, leading to a market size of EUR 1 billion [8]. - Europe has around 27,600 incidence cases, with a market size of EUR 770 million [8]. - The Asia-Pacific region reports 27,800 incidence cases, with a market size of EUR 250 million [8]. Group 4: Clinical Development and Intellectual Property - The Phase 1 trial aims to determine the maximum tolerated dose (MTD) of AB8939, with 28 patients enrolled in the first step and 10 in the second step [11]. - Future steps include evaluating the MTD after 14 consecutive days of treatment in combination with venetoclax or azacitidine [12]. - AB8939's intellectual property rights in AML are secured until 2036, with potential extension until 2044 for specific chromosome abnormalities [18].