Adjusting the carbidopa/levodopa ratio to reduce orthostatic hypotension in MSA-P and Parkinson's

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This Phase 1/2 interventional feasibility study enrolls adults with MSA-P or Parkinson disease who have orthostatic hypotension and are on levodopa combined with carbidopa or benserazide. Participants will undergo controlled administration of carbidopa/levodopa with adjustments to the carbidopa-to-levodopa ratio while investigators monitor standing and supine blood pressure and symptom scores. Study visits include a required medication withdrawal period before testing, orthostatic vital sign measurements, and symptom assessments using established autonomic questionnaires. The single-center trial at CHUV (Lausanne) aims to collect safety and preliminary efficacy data to inform larger trials.

Why it matters

Who can join: the full rules

Inclusion Criteria:

1. Informed consent form signed.
2. Patient over 18 years and under 80 years of age.
3. Patient with Multiple System Atrophy- Parkinsonian type (MSA-P) (confirmed by diagnostic criteria for clinically established and clinically probable multiple system atrophy (11); OR Patient with Parkinson Disease (PD) (12) presenting OH symptoms (getting at least one point at the 3 questions - n° 14, 15 and 16 - of the SCOPA-AUT scale that address orthostatic hypotension symptoms).
4. Patient currently receiving Dopamine-Replacement Therapy (i.e. Levodopa combined with Carbidopa or Benserazide).

Exclusion Criteria:

1. Patient unable to stand an overnight (at least 12 hours) withdrawal of their immediate-release DRT (last extended-, delayed-, or controlled-release dosage must be taken minimum 24 hours prior to the test).
2. Patient with known congestive heart failure, grades C and D, NYHA III and IV.
3. Patient with dementia (i.e. major cognitive impairment) associated to MSA-P or PD,
4. Patient with mild cognitive impairment, and unable to provide or understand informed consent, i.e. who does not have full capacity for discernment.
5. Current participation to other clinical trials.
6. Pregnant or lactating woman or willing to become pregnant.

Where it's running

• Centre Hospitalier Universitaire Vaudois (CHUV)
  Lausanne, Canton of Vaud, Switzerland Recruiting
• Centre Hospitalier Universitaire Vaudois
  Lausanne, Canton of Vaud, Switzerland Recruiting

Study contacts

• Study coordinator: Julien BALLY, Dr PD-MER
• Email: julien.bally@chuv.ch
• Phone: +41 79 556 78 19

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.