Study of IPX203 compared to levodopa/carbidopa in patients with advanced Parkinson’s disease and motor fluctuations

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What is this study about?

This clinical trial focuses on patients with advanced Parkinson’s disease who experience motor fluctuations – periods when movement becomes more difficult as medication wears off. The study tests a new medication called IPX203, which contains two active substances: levodopa and carbidopa. These substances are already used to treat Parkinson’s disease, but IPX203 is a new modified-release capsule formulation that may work differently than existing treatments.

The purpose of the study is to compare IPX203 with standard immediate-release levodopa/carbidopa treatment to see if it can better improve the time when patients have good control of their movement symptoms. The medication will be given as capsules that patients take by mouth. The study will look at how well patients’ symptoms are controlled throughout the day and how long the medication’s effects last.

During the 12-week study, participants will be randomly assigned to receive either IPX203 or standard levodopa/carbidopa treatment. They will need to keep track of their symptoms in a diary and undergo regular evaluations to assess how well the treatment is working. The medication comes in different strength capsules to allow for proper dose adjustment based on individual patient needs.

1 Initial evaluation

You will begin participation in a study comparing two medications for Parkinson’s disease: a new medication called IPX203 and standard immediate-release levodopa/carbidopa.

Your current symptoms and medical condition will be assessed to establish a baseline for comparison.

2 Medication assignment

You will be randomly assigned to receive either IPX203 or immediate-release levodopa/carbidopa.

Both medications are taken by mouth.

The immediate-release medication is taken 5 or more times per day, with a minimum total daily dose of 500 mg.

3 12-week treatment period

You will take the assigned medication for 12 weeks.

During this period, you will need to keep a daily diary recording your symptoms.

The diary will track your ‘ON time’ (periods when medication is working well) and ‘OFF time’ (periods when symptoms return).

The diary will also record any movement difficulties (dyskinesia) you experience.

4 Final evaluation

After 12 weeks, your condition will be reassessed.

The main focus will be on changes in your ‘good ON time’ compared to the start of the study.

Other measurements will include changes in OFF time and various types of ON time (with and without movement difficulties).

Clinical assessments will be performed to evaluate your overall condition.

Who Can Join the Study?

  • Must be at least 40 years old at the time of providing consent for participation
  • Must have been diagnosed with Parkinson’s disease according to specific diagnostic criteria and currently taking stable doses of immediate-release levodopa/carbidopa medication for at least 6 months before screening
  • Must have moderate to advanced stage Parkinson’s disease (Hoehn and Yahr Stages 2.5 to 4) when medications are working effectively
  • Must experience daily predictable “wearing-off” episodes (times when medication effects fade and symptoms worsen) for at least 4 weeks before screening
  • Must have at least 3 hours per day when medications are not working effectively (OFF time) during waking hours
  • Must be taking levodopa/carbidopa medication at least 5 times per day with a total daily dose of at least 500 mg
  • If taking levodopa/carbidopa with a COMT inhibitor (a type of medication that helps levodopa work longer), must be taking it 3 to 6 times daily
  • Can be of any gender identity (male, female, or other)

Who Cannot Join the Study?

  • History of brain surgery for Parkinson’s disease, including deep brain stimulation (a surgical procedure where electrodes are placed in the brain)
  • Presence of other significant neurological conditions besides Parkinson’s disease
  • History of psychiatric disorders that could interfere with the study
  • Significant heart, liver, or kidney disease
  • Current use of medications that could interact with the study drug
  • Pregnancy or breastfeeding
  • Previous adverse reactions to levodopa or carbidopa (medications used to treat Parkinson’s disease)
  • Participation in another clinical trial within the past 30 days
  • Inability to follow study procedures or attend scheduled visits
  • Uncontrolled high blood pressure
  • History of drug or alcohol abuse within the past year
  • Severe digestive problems that could affect medication absorption
  • Major surgery planned during the study period

Where you can join this trial?

Verified and Recommended Sites

No sites found in this category

Verified Sites

Site Name City Country Status
Niepubliczny Zaklad Opieki Zdrowotnej Neuromed M. I M. Nastaj. sp.p. Lublin Poland
Futuremeds Sp. z o.o. Wroclaw Poland

Other Sites

Site Name City Country Status
Etg Neuroscience Sp. z o.o. Warsaw Poland
Fondazione Istituto Neurologico Nazionale Casimiro Mondino Pavia Italy
Hospital Universitario Puerta De Hierro De Majadahonda Majadahonda Spain
Hospital Universitario 12 De Octubre Madrid Spain
Centrum Medyczne Neuromed Sp. z o.o. Bydgoszcz Poland
Krakowska Akademia Neurologii Sp. z o.o. Cracow Poland
Azienda Ospedaliera di Padova Padua Italy
Irccs San Raffaele Roma S.r.l. Rome Italy
Universita’ Politecnica Delle Marche Ancona Italy
Neuroprotect Sp. z o.o. Warsaw Poland
Neurologia Śląska Centrum Medyczne Katowice Poland
Hpficthi Upxioocbydyvf Dv Ls Phgupojj Madrid Spain
Nfiskmiz Bkhfmselsmedd Tcasvqvszwh Lirrkqf svflz Cracow Poland
Nvoavohnwa Spd z otpn sigjj Katowice Poland
Cpnyuam Zspqyvm I Utjjm Mxhtsea Lublin Poland
Hibaover Dw Lz Svcuy Cewy I Sxeq Pvf Barcelona Spain
Ibeyz Otxrsozb Auigzwwtqj Ste Lxqf Milan Italy

Want to learn more about this study or check if you can participate? Contact us.

Trial status

Country Status Recruitment Start
Italy Italy
Recruiting
20.08.2025
Poland Poland
Recruiting
20.08.2025
Spain Spain
Recruiting
20.08.2025

Trial locations

IPX203 is an investigational medication designed to treat advanced Parkinson’s disease. It is a new formulation that combines levodopa and carbidopa in a way that may provide longer-lasting symptom control for patients with Parkinson’s disease who experience motor fluctuations.

Levodopa/Carbidopa immediate-release is a standard treatment for Parkinson’s disease. Levodopa works by being converted to dopamine in the brain, which helps control movement symptoms. Carbidopa prevents levodopa from being broken down before it reaches the brain, allowing more of it to be effective in treating Parkinson’s symptoms.

Parkinson’s Disease – A progressive neurological disorder that affects movement and motor control. The condition develops when nerve cells in the brain that produce dopamine begin to decline or die. Early symptoms include slight tremors, usually starting in the hands, along with stiffness and slowing of movement. As the disease advances, patients experience periods of reduced mobility (OFF time) alternating with periods of better movement control (ON time). Motor fluctuations become more pronounced in advanced stages, where patients may switch between periods of good mobility and periods of significant movement difficulties. Some patients may develop dyskinesia, which causes involuntary, uncontrolled movements, particularly when medication effects peak.

Trial ID:
2025-521772-57-00
Protocol code:
ZB203L01
Trial Phase:
Therapeutic confirmatory (Phase III)

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