Mentara Therapeutics Advances MTA-304 for Parkinson’s

SAN DIEGO and SYDNEY, October 7, 2026

Mentara Launches With Phase 2-Ready Parkinson’s Program

MTA-304 is an investigational PDE10A inhibitor designed to address involuntary and uncontrolled movements that can develop in people receiving long-term levodopa therapy for Parkinson’s disease. Levodopa remains one of the most effective treatments for Parkinson’s symptoms, but approximately 40% to 50% of patients receiving long-term therapy may develop dyskinesia within four to six years, according to the company. The development of LID can create a significant treatment challenge because physicians and patients may need to balance control of Parkinson’s symptoms against disabling involuntary movements. Amantadine extended release is currently the only FDA-approved therapy for LID, while side effects including hallucinations, dizziness and swelling can limit its use for some patients. Mentara’s launch is centered on advancing MTA-304 as a potential new therapeutic approach. The company said the program has already generated a Phase 1 clinical package, providing a foundation for the planned Phase 2 study. Under the transaction, EuMentis shareholders will become shareholders in Mentara, while financial terms of the acquisition were not disclosed. EuMentis, which previously licensed EM-221 from Mochida Pharmaceutical Co., Ltd., will be wound down following completion of the transaction.

MTA-304 Shows Promise in Preclinical Dyskinesia Models

MTA-304 has completed three Phase 1 studies involving 86 subjects, with the studies demonstrating what the company described as a favorable safety and tolerability profile. Beyond the clinical safety package, preclinical findings have provided additional support for the candidate’s development in LID. In a non-human primate model of levodopa-induced dyskinesia, MTA-304 reduced dyskinesia by 40% without reducing levodopa’s therapeutic benefit. In a separate rat model, the investigational therapy reportedly outperformed amantadine. The candidate’s mechanism is designed to address signaling changes associated with dyskinesia while preserving the benefits of levodopa. PDE10A is an enzyme found almost exclusively in the striatum, a brain region implicated in the development of levodopa-induced dyskinesia. By selectively inhibiting PDE10A, MTA-304 is intended to rebalance striatal signaling pathways that can become overstimulated by levodopa. The company believes this mechanism could potentially reduce dyskinesia without diminishing levodopa’s ability to control core Parkinson’s symptoms.

Phase 2 Study Planned for First Half of 2027

With the acquisition completed, Mentara plans to move MTA-304 into a Phase 2 clinical study during the first half of 2027. The upcoming study is expected to provide an important clinical test of whether the preclinical activity and Phase 1 safety findings translate into meaningful therapeutic effects for people living with Parkinson’s disease and LID. The company’s immediate objective is to generate clinical evidence that can determine the potential of MTA-304 as a new treatment option for patients whose involuntary movements remain difficult to manage. Mentara is led by Frank Stonebanks, who brings more than 25 years of experience across biotechnology operations and venture capital. Stonebanks previously served as CEO of EuMentis and held leadership positions across several life sciences investment and biotechnology organizations. SPRIM Global Investments, which backs Mentara, is a life sciences investment firm focused on clinical-stage therapeutics, digital health and research and development infrastructure. The launch gives Mentara a dedicated platform to advance MTA-304 toward its next clinical milestone and potentially expand treatment options for Parkinson’s disease-related dyskinesia.

Source: Mentara Therapeutics press release