Duodopa (Duopa, ABT-SLV187), also known as levodopa/carbidopa intestinal gel (LCIG), is a formulation of levodopa and carbidopa developed by AbbVie. It is administered via the intestines for a 16-hour period as a therapy for patients with advanced Parkinson’s disease.

Duodopa was approved by the Swedish Medical Products Agency (MPA) in 2004, followed by the European Medicines Agency (EMA) for the rest of Europe. The U.S. Food and Drug Administration (FDA) granted Duodopa orphan drug designation in 2015. In the same year, the National Health Service (NHS) England also announced funding and approval of Duodopa use to treat Parkinson’s.

How Duodopa works

Parkinson’s disease is a condition affecting the brain that results in a progressive loss of control and coordination. It is caused by the loss of neurons in the brain that produce the neurotransmitter  (cell-signaling) molecule dopamine. Dopamine is required for the transmission of electric signals between nerve cells and from the brain to various muscles in the body.

Duodopa is a combination of levodopa and carbidopa in a 4:1 ratio. Parkinson’s is characterized by reduced dopamine levels. However, dopamine cannot be directly administered because it cannot cross the blood-brain barrier. Levodopa is the chemical building block from which dopamine is synthesized in the body. Levodopa can cross the blood-brain barrier easily and be converted to dopamine in the brain, preventing muscle stiffness or involuntary movements.

Carbidopa is an agent that helps prevent the breakdown of levodopa so that more of it is available to the brain to make dopamine. This reduces the amount of levodopa that needs to be administered, thereby reducing side effects of levodopa treatment such as nausea and vomiting.

For those in advanced stages of Parkinson’s with uncontrollable involuntary movements (dyskinesia), Duodopa is administered as a gel suspension through a tube that is surgically inserted into the intestine. A pump helps  deliver the required dosage through the tube. This method ensures that a steady concentration of Duodopa is available in the blood at all times.

Duodopa in clinical trials

Duodopa pump therapy was tested in 14 patients in Denmark with advanced Parkinson’s disease. The results showed that Duodopa significantly reduced involuntary movements and improved posture after 24 hours of treatment.

A Phase 4 long-term health economics study (NCT00141518) of Duodopa in patients with advanced Parkinson’s disease was completed in 2011. The study found that Duodopa is a more cost-effective treatment option compared to standard-of-care therapy in patients with advanced Parkinson’s disease.

A Phase 1 observational study (NCT01747655) of activities of daily living in patients with advanced Parkinson’s disease treated with Duodopa was completed in 2015. The study reported a decrease in disability of the patients and increased ability to carry out normal daily activities.

Other information

Duodopa is usually administered in three doses:

  • A morning bolus dose that approximately amounts to 100-200 mg of levodopa.
  • A continuous maintenance dose that is administered over 16 hours amounting to 20-200 mg of levodopa per hour.
  • An extra bolus dose in the event the patient has difficulty in movement during the day. The extra dose is adjusted depending on the level of movement difficulty.

Duodopa may cause serious side effects, including hallucinations, falling asleep during normal activities, depression, and uncontrolled movement.

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Parkinson’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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Ana holds a PhD in Immunology from the University of Lisbon and worked as a postdoctoral researcher at Instituto de Medicina Molecular (iMM) in Lisbon, Portugal. She graduated with a BSc in Genetics from the University of Newcastle and received a Masters in Biomolecular Archaeology from the University of Manchester, England. After leaving the lab to pursue a career in Science Communication, she served as the Director of Science Communication at iMM.