Multi-centered, placebo-controlled, double-blind, randomized clinical trial to assess the effect of oral inosine on the onset of wearing off in patients with early stage Parkinson's disease

Multi-centered, placebo-controlled, double-blind, randomized clinical trial to assess the effect of oral inosine on the onset of wearing off in patients with early stage Parkinson's disease - Randomized clinical trial to assess the disease modifying effect of oral inosine for patients with Parkinson's disease

Status

Recruiting

Phases

Phase 2

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000020527

Enrollment

100

Registered

2016-02-01

Start date

2016-02-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Parkinson&#39

Interventions

Inosine to maintain a serum urate level between 6.0-7.5 mg/dL for 2 years Lactose as a placebo for 2 years

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Diagnosed as having Parkinson's disease according to UK Parkinson's Disease Society Brain Bank criteria. Within 5 years (60 months) from the start of any anti-Parkinsonism medication. 19 item-Wearing-off questionnaire <= 1 at the time of the screening visit and Visit 1. Serum urate level <= 5.5 mg/dL in male or <= 4.2 mg/dL in female. Age >=20 and obtained written informed consent.

Exclusion criteria

Exclusion criteria: A history of kidney stones, gout(or chronic arthritis), ischemic heart disease A history of kidney failure of eGFR <= 60 at the screening visit. Having uncontrolled hypertension which is defined as SBP>=160 or DBP >=100 Current treatment with medication which slows urate excretion, which is defined as taking diuretics, losartan, anti-tuberculosis drugs or immune-suppression agents. Being pregnant or having an intention to become pregnant during the study period. Other factors that investigators deem inappropriate to enroll for the trial. (e.g. Having malignancy, arthritis which is difficult to discern from gout, severe allergic history to drugs)

Design outcomes

Primary

Measure	Time frame
Time between the first administration of the drug to the onset of wearing off (19 item-Wearing-off questionnaire > 2)	—

Secondary

Measure	Time frame
Time taken to reach Hoehn&Yahr 3.0 or above Score change in UPDRS Medication of levodopa over 300 Change in SBR in DATSCAN Change in H/M in MIBG	—

Countries

Japan

Contacts

Public ContactHirotaka Iwaki

Ehime University Graduate School of Medicine Department of Neurology and Clinical Pharmacology

h-iwaki@m.ehime-u.ac.jp089-960-5095

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026

Multi-centered, placebo-controlled, double-blind, randomized clinical trial to assess the effect of oral inosine on the onset of wearing off in patients with early stage Parkinson&#39;s disease