CAMBRIDGE, UK, October 15, 2026
Mission Therapeutics Limited, a clinical-stage biotechnology company developing treatments designed to restore cellular health by removing dysfunctional mitochondria, announced that the first patient has been dosed in its Phase 1b clinical study of MTX325 in Parkinson’s disease (PD). The patient received the investigational treatment at Royal Liverpool University Hospital in the United Kingdom. The MTX325-101 study will evaluate clinical proof-of-mechanism, safety and tolerability in 36 patients with mild to moderate Parkinson’s disease across the UK, Europe and Australia. MTX325 is a first-in-class, highly potent and selective, orally bioavailable, brain-penetrant inhibitor of the deubiquitinating enzyme USP30. The candidate is designed to improve mitochondrial quality control by promoting the clearance of dysfunctional mitochondria, a process that may help maintain cellular health. The Phase 1b study follows the successful completion of a Phase 1a single- and multiple-ascending-dose study in healthy volunteers. Mission expects to report data from the ongoing Phase 1b trial in late 2027.
Phase 1b Study Evaluates Mechanism and Safety
The MTX325-101 study is designed to establish whether the investigational candidate demonstrates its intended biological activity in people with Parkinson’s disease. Researchers will assess biological and pathophysiological responses using a range of biomarkers and imaging measures, alongside safety and tolerability evaluations. The trial is expected to enroll 36 participants with mild to moderate idiopathic Parkinson’s disease across clinical sites in the UK, Europe and Australia. Recruitment is ongoing, and the first patient has now entered the study. Mission Therapeutics Chief Development Officer Dr. Sarah Fritchley described the first dose as an important milestone in evaluating MTX325’s potential as a disease-modifying treatment. She emphasized the contribution of the international investigator network to the study’s proof-of-mechanism assessment. Chief Medical Officer Dr. Suhail Nurbhai said the program aims to explore whether improving mitochondrial quality control could eventually provide an approach that goes beyond the symptom management offered by existing Parkinson’s treatments. The Phase 1b study is an early clinical investigation and is intended to establish biological evidence and further characterize the candidate’s safety. It is not designed, on the information provided, to establish definitive disease-modifying efficacy. The anticipated late-2027 data readout is expected to provide further insight into MTX325’s activity in patients and inform decisions about its subsequent development.
MTX325 Targets Mitochondrial Quality Control
MTX325 is designed to inhibit USP30, a deubiquitinating enzyme involved in the regulation of mitochondrial quality control. By inhibiting USP30, the candidate is intended to promote the removal of dysfunctional mitochondria through mitophagy, the cellular process responsible for clearing damaged mitochondria. Mission’s approach is based on the premise that improving mitochondrial clearance may support cell health and reduce inflammation associated with disease processes. In preclinical studies, MTX325 demonstrated effects across several areas relevant to Parkinson’s disease, including increased mitophagy, beneficial effects on alpha-synuclein accumulation and effects on nigrostriatal dopaminergic neurons. These findings provide the scientific rationale for continued investigation, but the reported effects were observed in preclinical models and do not establish clinical benefit in humans. Parkinson’s disease is a progressive neurodegenerative condition associated with the loss or dysfunction of dopamine-producing neurons and can affect movement and other aspects of health. Current treatments can help manage symptoms, but Mission is investigating whether targeting mitochondrial dysfunction could offer a different therapeutic approach. The company describes MTX325 as a potential disease-modifying candidate because it is intended to address biological processes associated with disease progression rather than symptoms alone. Whether this mechanism can meaningfully slow disease progression in patients will require evidence from clinical trials.
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Phase 1a Results Support Continued Clinical Development
The Phase 1b program follows completion of a Phase 1a single-ascending-dose and multiple-ascending-dose (SAD/MAD) study in healthy volunteers. According to Mission, the earlier study demonstrated high central nervous system penetration. A separate positron emission tomography (PET) study confirmed distribution of MTX325 into the brain parenchyma, the functional tissue of the brain. These findings provide preliminary information about the candidate’s ability to reach its intended area of activity. The ongoing patient study will build on this earlier work by investigating biological responses and safety in people living with Parkinson’s disease. Mission’s development strategy centers on small-molecule therapies that promote the removal of dysfunctional mitochondria to improve cellular function. MTX325 is currently its candidate targeting the central nervous system through USP30 inhibition. The company is backed by investors including Pfizer Venture Investments, Sofinnova Partners, Roche Venture Fund, SR One, IP Group and Rosetta Capital. The next key milestone is the expected Phase 1b data readout in late 2027. Those findings will help determine whether the biological effects suggested by preclinical research and early healthy-volunteer studies can be demonstrated in patients and whether further clinical development is warranted. Until additional clinical evidence becomes available, MTX325 remains investigational and its potential to alter the course of Parkinson’s disease has not been established.
Source::Mission Therapeuticspress release
