Pharos iBio Co., Ltd. announced on the 14th that a paper detailing the preclinical studies of rasmotinib has been published in “Leukemia,” a sister journal of *Nature* and an international academic journal specializing in blood cancers.
The paper presents the results of preclinical studies evaluating Rasmotinib’s anticancer efficacy and its potential to overcome resistance to the existing FLT3 inhibitor. Professor Donald Small of the Johns Hopkins University School of Medicine in the U.S., a world-renowned authority in the field of acute myeloid leukemia, served as the corresponding author. Professor Small is an expert who has conducted research on the FLT3 protein—which is involved in the growth and proliferation of blood cells—as well as the mechanisms underlying leukemia development and the development of targeted therapies.
This study was conducted in an animal model that replicated the leukemic environment within the bone marrow using cells derived from AML patients. A key feature of this study is that it examined drug efficacy within the bone marrow environment where leukemia develops, unlike methods that involve implanting tumors subcutaneously.
In the animal model using cells derived from AML patients, the median survival time in the rasmotinib treatment group was 191 days. This represents an extension of 83 days compared to the control group (108 days) and 58 days compared to the group treated with gilteritinib, an existing FLT3-targeted therapy (133 days).
Improved survival was also observed in animal models with acquired resistance mutations to existing therapies. Patients with FLT3-mutant AML may develop acquired resistance mutations, such as “FLT3-ITD-F691L,” while being treated with targeted therapies like quizartinib and gilteritinib. When this mutation occurs, the efficacy of existing drugs decreases, potentially limiting treatment options.
In the animal model of this resistance mutation, the survival period in the rasmotinib group was 44.4 days, exceeding both the gilteritinib group (21.4 days) and the control group (19.4 days). In particular, rasmotinib demonstrated a survival period that was 25 days longer than the control group and 23 days longer than the gilteritinib group, and it was the only treatment group to demonstrate a statistically significant survival benefit.
Yoon Jeong-hyeok, CEO of Pharos iBio Co., Ltd., “This study is significant in that it confirmed the anticancer efficacy of rasmotinib using an animal model that replicates the disease in the bone marrow, where leukemia originates,” he said. “In particular, since it has demonstrated activity even in models with resistance mutations to existing FLT3-targeted therapies, we will continue to validate its clinical efficacy and safety through follow-up clinical development so that it can establish itself as a new treatment option.”
He continued, “In line with our ‘Pharos iBio Co., Ltd. 2.0’ strategy, we will continue to enhance our proprietary AI-based drug discovery platform, ‘Chemiverse,’ and expand global open innovation to strengthen the foundation for the development and commercialization of our key pipeline candidates, including rasmotinib.”
Meanwhile, Pharos iBio Co., Ltd. has completed a Phase 1 clinical trial of Rasmotinib in patients with relapsed or refractory AML, achieving a clinical response rate of 50% for complete remission with complete cytoreduction (CRc). The company is currently formulating a development strategy to advance to a subsequent global Phase 2 clinical trial while concurrently conducting discussions with global pharmaceutical companies regarding technology transfer (L/O) and business development. The company is currently in technology transfer discussions with multiple potential partners both domestically and internationally, with the goal of securing technology transfer deals by the end of this year or early next year.
