Accent Therapeutics Begins Phase 1/2 Trial of ATX-295 and Gets FDA Fast Track for ATX-295 and ATX-559

Accent Therapeutics, a biopharmaceutical company in the clinical stage of development, has announced a major milestone with the first patient dosed in its inaugural Phase 1/2 clinical trial of ATX-295. This trial is designed to assess the safety and tolerability of ATX-295, an oral inhibitor targeting KIF18A, a key protein involved in cell division in certain tumors. The company is focusing on cancers with high chromosomal instability, such as ovarian and certain breast cancers, which currently have limited treatment options. The study aims to address this gap by advancing a drug that shows potential as a best-in-class treatment option.

ATX-295 functions by selectively inhibiting KIF18A, which is crucial for cell division in cancer cells with chromosomal irregularities but not in healthy cells. Preclinical models have demonstrated that ATX-295 can inhibit tumor growth in a dose-dependent manner, which supports its progression into clinical evaluation. The ongoing Phase 1/2 trial is open-label and involves dose-escalation and expansion phases. It is set to explore several aspects of the drug, including its safety, pharmacokinetics, pharmacodynamics, and preliminary efficacy when administered orally. This trial is currently enrolling patients with locally advanced or metastatic solid tumors, with a focus on high-grade serous ovarian cancer.

In parallel with the ATX-295 trial, Accent Therapeutics is also advancing ATX-559, a first-in-class inhibitor targeting DHX9. This protein plays a significant role in tumors exhibiting high levels of replication stress. The DHX9 inhibitor is being investigated for its potential to exploit vulnerabilities in tumors with deficiencies in DNA repair mechanisms or in hyper-mutated states, such as MSI-H/dMMR. The company is exploring the possibility of combining DHX9 inhibitors with other cancer therapies to enhance treatment outcomes.

Both ATX-295 and ATX-559 have received Fast Track designation from the U.S. Food and Drug Administration (FDA). This designation is significant as it acknowledges the potential of these investigational drugs to meet urgent medical needs in patients with serious conditions. Fast Track status facilitates the development and accelerates the review process, aiming to expedite the availability of these therapies to patients in need.

Accent Therapeutics will be sharing further data related to these clinical advancements at upcoming medical conferences. The company is set to present new preclinical data at the 2025 AACR Annual Meeting and a trial-in-progress update on ATX-559 at the 2025 ASCO Annual Meeting. These presentations will provide insights into the ongoing research and support for the clinical evaluation of both investigational drugs.

By focusing on novel targets like KIF18A and DHX9, Accent Therapeutics is at the forefront of developing precision cancer therapies. Their innovative approach seeks to transform cancer treatment by offering targeted therapies that address specific intracellular dependencies across multiple cancer types. This strategy is aimed at benefiting large patient populations with significant unmet medical needs, ultimately working towards improving outcomes for those affected by cancer.