2025-521819-39-00RecruitingPhase 2
TADalafil in early-stage Parkinson’s Disease (TAD-PD)
Prospective, Open-Label, Single-Center Pilot Study on the Efficacy of Daily Tadalafil in Early-Stage Parkinson’s Disease
Source: EU CTIS (euclinicaltrials.eu) · Last updated 5 Jan 2026
Brief summary (registry, in English)
To assess whether daily tadalafil improves motor symptoms in Parkinson-drug naïve patients with early-stage Parkinson’s disease over a two-week follow-up period
- Status (registry)
- Recruiting
- Phase (registry)
- Phase 2
- Study type
- Interventional
- Enrollment
- 20 (estimated)
- First submitted
- 23 Sept 2025
- Start date
- 2 Mar 2026
- Lead sponsor
- Amsterdam UMC Stichting
- Diseases
- Parkinson disease
- EU CT number
- 2025-521819-39-00
What you commit to
- Study type: Interventional · Phase 2
- Planned participants: 20
- 1 site in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of EU CTIS (euclinicaltrials.eu). It describes the study design.
AI-kivonat: who the study is looking for
Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults with early-stage Parkinson's disease who have never taken Parkinson's medicine. It tests daily tadalafil over two weeks.
- Age
- Older than 18 years
- Sex
- All sexes can join
- Disease stage
- Early-stage Parkinson's disease, with no limits in daily life that would need symptom treatment
- Earlier treatment
- No earlier medicine for Parkinson's disease
Main reasons for not taking part
- Taking PDE-inhibitors for erectile dysfunction
- Unstable heart or brain blood vessel disease
- Multisystem atrophy (MSA), mild cognitive impairment or dementia
- Kidney problems (eGFR below 80 ml/min) or liver problems
- Pregnancy or breastfeeding
Read by machine on 9 Nov 2026.
Who cannot take part
Copied verbatim from EU CTIS (euclinicaltrials.eu) and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Currently taking PDE-inhibitors for erectile dysfunction.
- Concurrent nitrate, nitric oxide donors, guanylate cyclase, nicorandil, theophylline alpha-blocker, cytochrome P-450 3A4 (CYP3A4) inhibitor/inducer, or prostacyclin analog use.
- Significant alcohol or drug abuse.
Other illness
- (unstable) Cardiovascular and cerebrovascular disease.
- Unilateral blindness, hereditary retinal disorders, or increased risk of blindness.
- Unilateral deafness or history of severe hearing loss dependent upon hearing aid(s).
- Mild cognitive impairment (MCI) or dementia.
Lab values
- Suspicion of or a known history of renal (eGFR level < 80 ml/min) or hepatic insufficiency.
Other
- Multisystem atrophy (MSA).
- Abnormal electrocardiogram (ECG).
- Orthostatic hypotension: a decrease in systolic blood pressure ≥ 20 mmHg, or a decrease in diastolic blood pressure ≥ 10 mmHg.
- Immunocompromised.
- Pregnancy and breastfeeding.
- Legally incompetent adults.
- Clinically significant penile deformity.
Who the study is looking for
- Diagnosis of early-stage Parkinson’s disease, with no limitations in daily functioning that would necessitate symptomatic treatment
- No prior medication for Parkinson’s disease.
- Normal blood pressure (between >90/60 mm Hg and <120/80 mm Hg).
- Age older than 18 years.
- Informed consent and comply with the study protocol.
- Understand the Dutch language.
Age in the registry: 18 years to - · Sex: All · Does not accept healthy volunteers
Sites (1)
Sites in registry order. Save your city in your profile to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Amsterdam UMC Research B.V. | Amsterdam | Netherlands | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.