# UDCA liver drug demonstrates safety and midbrain target engagement in phase II Parkinson's trial

- Published: 2026-11-07 13:47 UTC
- Section: Life & Health › Medicine
- Tags: ursodeoxycholic acid Parkinson's trial, high-dose UDCA safety phase II, midbrain phosphorus MRS ATP hydrolysis, sensor-based gait analysis Parkinson's, MDS-UPDRS-III trial results UDCA
- URL: https://realtech.media/news/rt-0eda9dc267c00d9a5144b27b_udca_liver_drug/

**A phase II study showed that high-dose ursodeoxycholic acid is well tolerated and improves midbrain energy markers in early Parkinson's disease.**

![UDCA liver drug demonstrates safety and midbrain target engagement in phase II Parkinson's trial](https://realtech.media/media/2026/11/5b4f2ddedd910be5.jpg)
*NASA Johnson Space Center, Wikimedia Commons, Public domain*

High-dose ursodeoxycholic acid (UDCA), a drug conventionally used to treat liver disease, is safe, well tolerated, and demonstrates target engagement in the midbrain of patients with early Parkinson's disease, according to the phase II UP trial published in *Movement Disorders* [1]. The randomized, double-blind, placebo-controlled study enrolled 30 participants across a 48-week period to assess whether restoring mitochondrial function could act as a neuroprotective strategy [1].

Participants were randomized in a 2:1 ratio to receive either daily high-dose UDCA at 30 mg/kg or a matching placebo [1]. The primary outcome focused on safety and tolerability, while secondary outcomes examined midbrain bioenergetics using phosphorus magnetic resonance spectroscopy (31P-MRS) and measured motor progression using both the Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS-III) and sensor-based gait quantification [1].

## Bioenergetic markers and target engagement

The treatment regimen proved safe and well tolerated overall, with mild, transient gastrointestinal adverse events occurring more frequently in the UDCA cohort than in the placebo group [1]. In secondary assessments, midbrain 31P-MRS demonstrated an increase in both Gibbs free energy and inorganic phosphate levels among participants receiving UDCA [1]. Researchers noted that these spectroscopic shifts reflect an improvement in ATP hydrolysis, indicating that the molecule engages its targeted bioenergetic pathways within the midbrain [1].

## Motor progression and clinical evaluation

Objective motion sensor measurements revealed an improvement in cadence, measured in steps per minute, alongside improvements in other gait parameters in the UDCA arm compared to placebo [1]. Conversely, the subjective clinical scoring administered through the standard MDS-UPDRS-III protocol failed to detect any statistically significant difference between the treated and placebo groups [1].

UDCA had previously demonstrated efficacy as a mitochondrial rescue agent across preclinical in vitro and in vivo models of the disease [1]. The trial authors concluded that larger clinical trials are necessary to verify whether the identified target engagement translates into disease-modifying clinical outcomes for patients with Parkinson's disease [1].

## Sources

1. [Movement Disorders](https://doi.org/10.1002/mds.29450)
2. [knowridge.com](https://knowridge.com/2026/11/could-a-common-liver-medicine-slow-parkinsons-disease)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-0eda9dc267c00d9a5144b27b_udca_liver_drug/