Istradefylline for Parkinson's Disease with Cognitive Impairment

Overseen By Kara McHaney

Age: 18+

Sex: Any

Trial Phase: Phase 2

Sponsor: Virginia Commonwealth University

Must be taking: Carbidopa/levodopa

Disqualifiers: Dementia with Lewy bodies, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Approved in 2 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 4

Duration: 26 weeks

10 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but it requires that your antiparkinsonian medications and cholinesterase inhibitor doses are stable for a certain period before starting the trial.

What data supports the effectiveness of the drug istradefylline for Parkinson's Disease with Cognitive Impairment?

Istradefylline has been shown to reduce 'OFF' time (periods when medication is not working well) in patients with Parkinson's Disease, and it is well tolerated, making it a promising option for those with advanced stages of the disease, including those with cognitive issues. ^{1 2 3 4 5}

Is istradefylline safe for humans?

Istradefylline has been studied for safety in people with Parkinson's disease, and common side effects include dizziness, constipation, nausea, hallucinations, and trouble sleeping. It is generally considered safe when used with other Parkinson's treatments, but more studies are needed to understand its long-term effects. ^{1 2 4 5 6}

How is the drug Istradefylline unique for treating Parkinson's disease with cognitive impairment?

Istradefylline is unique because it works by blocking a specific brain receptor (adenosine A2A) to help reduce 'OFF' time in Parkinson's patients, which is when symptoms return between medication doses. It is also noted for having fewer side effects, making it suitable for patients with cognitive issues or depression. ^{1 2 3 5 7}

What is the purpose of this trial?

The purpose of this research study is to determine whether istradefylline improves cognition in individuals with Parkinson disease with cognitive impairment.

Research Team

Matthew Barrett, MD

Principal Investigator

Virginia Commonwealth University

Eligibility Criteria

This trial is for individuals over 50 with Parkinson's disease who are experiencing cognitive impairment. They must be in the early to moderate stages of the disease, taking carbidopa/levodopa, and have stable medication doses. Those with dementia related to Lewy bodies, severe liver issues, or women who could become pregnant aren't eligible.

Inclusion Criteria

My Parkinson's medication has been the same for the last 4 weeks.

I am currently on carbidopa/levodopa medication.

I am over 50 years old.

Exclusion Criteria

My liver is not working well.

Dementia too severe to complete study measures or to adhere to medication schedule

I experience significant involuntary movements.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive usual care and take istradefylline daily for 26 weeks

26 weeks

4 visits (in-person) at baseline, 4 weeks, 14 weeks, and 26 weeks

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Istradefylline

Trial Overview The study is testing whether a drug called Istradefylline can improve thinking and memory skills in people with Parkinson's disease who also have cognitive impairments.

Participant Groups

Group I: Usual care plus istradefylline Experimental Treatment 1 Intervention

Participants will receive usual care, and in addition, will be asked to take istradefylline daily for 26 weeks.

Istradefylline is already approved in United States, Japan for the following indications:

Approved in United States as Nourianz for:

• Parkinson's disease

Approved in Japan as Nouriast for:

• Parkinson's disease

Who Is Running the Clinical Trial?

Virginia Commonwealth University

Lead Sponsor

Trials

732

Recruited

22,900,000+

Kyowa Kirin, Inc.

Industry Sponsor

Trials

49

Recruited

5,700+

Findings from Research

Istradefylline, when used alongside levodopa, significantly reduces the time patients with Parkinson's Disease spend in the OFF state and improves motor function as measured by the Unified Parkinson's Disease Rating Scale (UPDRS) Part III.

The study found that istradefylline is safe, with no significant differences in adverse events compared to placebo, although it was associated with a higher risk of dyskinesia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Istradefylline, an adenosine A₂A receptor antagonist, for patients with Parkinson's Disease: a meta-analysis. Chen, W., Wang, H., Wei, H., et al.[2014]

Istradefylline is a newly approved adjunct treatment for Parkinson's disease that helps reduce 'off' episodes when used alongside the standard levodopa/carbidopa therapy, as demonstrated in four randomized, double-blind, placebo-controlled studies.

This drug works differently than traditional Parkinson's treatments by blocking adenosine A2A receptors, and while it can be effective, it may cause side effects like dyskinesia and dizziness, and its high cost could affect accessibility for patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Istradefylline: A novel agent in the treatment of "off" episodes associated with levodopa/carbidopa use in Parkinson disease. Cummins, L., Cates, ME.[2022]

References

1. Netherlands pubmed.ncbi.nlm.nih.gov

Istradefylline, an adenosine A₂A receptor antagonist, for patients with Parkinson's Disease: a meta-analysis. [2014]

2. United States pubmed.ncbi.nlm.nih.gov

Efficacy of adenosine A2A receptor antagonist istradefylline as augmentation for Parkinson's disease: a meta-analysis of randomized controlled trials. [2015]

3. England pubmed.ncbi.nlm.nih.gov

Istradefylline for the treatment of Parkinson's disease: is it a promising strategy? [2018]

4. England pubmed.ncbi.nlm.nih.gov

Safety and effectiveness of istradefylline in patients with Parkinson's disease: interim analysis of a post-marketing surveillance study in Japan. [2018]

5. Netherlands pubmed.ncbi.nlm.nih.gov

Efficacy of Istradefylline, an Adenosine A2A Receptor Antagonist, as Adjunctive Therapy to Levodopa in Parkinson's Disease: A Pooled Analysis of 8 Phase 2b/3 Trials. [2021]

6. United States pubmed.ncbi.nlm.nih.gov

Istradefylline: A novel agent in the treatment of "off" episodes associated with levodopa/carbidopa use in Parkinson disease. [2022]

7. England pubmed.ncbi.nlm.nih.gov

Istradefylline for Parkinson's disease patients experiencing motor fluctuations: results of the KW-6002-US-018 study. [2022]