Symptoms of Parkinson’s disease can affect your daily life and well-being. Nourianz (istradefylline) is a medicine used to reduce “off” time in people with Parkinson’s disease who are taking daily levodopa/carbidopa.
How Does Nourianz Work for Parkinson’s Disease?
“Off” episodes can occur when the effects of common medicines for Parkinson’s, such as levodopa, wear off, which causes symptoms to return or worsen. “Off” episodes can occur at varying times during the day.
The way Nourianz works for treating “off” episodes in people with Parkinson’s disease is not fully known. It is thought to block adenosine A2A receptors in the basal ganglia, a brain circuit group involved in Parkinson’s disease. Many medicines used for Parkinson’s disease target dopamine receptors in the basal ganglia, but evidence has shown that blocking adenosine A2A receptors with medicines like Nourianz can help reduce “off” time each day without worsening uncontrolled movements (dyskinesia).
Most people see improvements within one month of starting the medicine.
How Should I Take Nourianz?
Nourianz is an oral tablet that should be taken once daily with or without food. Taking Nourianz in the morning may reduce the chance of having trouble sleeping.
How Was Nourianz Studied?
Nourianz was studied in four 12-week clinical studies in people with Parkinson’s disease experiencing “off” episodes as an add-on treatment to levodopa/carbidopa. As explained above, “off” time is when Parkinson’s symptoms worsen and may happen when your Parkinson’s medicine begins to wear off.
Nourianz was compared to a placebo containing no medicine in the studies. People did not know if they were receiving Nourianz or a placebo. Adults could participate in the studies if they were experiencing at least two hours of “off” time per day and had been taking levodopa for at least one year, with a stable dose of levodopa for at least four weeks before the start of the study. People also had to have early or less advanced stages of Parkinson’s disease, specifically stage II, III, or IV on the Hoehn and Yahr scale. Based on this scale, stages I and II represent early stages of Parkinson’s disease, stages II and III mark the mid-stage, and stages IV and V indicate advanced stages. People were not allowed in the study if they had undergone a brain surgery for Parkinson’s disease.
The four studies included a total of 1,143 adults with Parkinson’s disease. The following describes the participants when they entered the study:
- The average length of time people had Parkinson’s disease was nine years, ranging from one month to 37 years.
- On average, people were experiencing six hours of “off” time each day at the beginning of the study.
- The average dose of levodopa people were receiving ranged from 416 to 785 mg per day.
- In addition to levodopa, many people in the study were also taking other medicines for Parkinson’s disease:
- 85% of people were taking a dopamine agonist (such as apomorphine, pramipexole, or ropinirole).
- 38% were taking a COMT inhibitor (such as entacapone or tolcapone).
- 40% were taking an MAO-B inhibitor (such as safinamide, selegiline, or rasagiline).
- 13% were taking an anticholinergic medicine (such as benztropine or trihexyphenidyl).
- 33% were taking amantadine.
The main goal was to see how much people’s daily “off” time changed from the start to the end of the study, based on 24-hour diaries completed by the participants. A second goal was to measure changes in “on” time when symptoms were controlled without bothersome involuntary movements (dyskinesia), including “on” time without dyskinesia and “on” time with mild, non-troublesome dyskinesia. “On” time refers to periods when symptoms are well-managed, and the medicine is effective.
What Were the Main Benefits Seen With Nourianz in Studies?
Across all four studies, people taking Nourianz spent less time each day in the “off” state (when Parkinson’s symptoms were not well controlled) and gained more “on” time without troublesome involuntary movements (dyskinesia), compared with those taking a placebo.
In the two studies conducted in the U.S. and Canada, people taking Nourianz gained about 58 minutes per day (study 1) and 33 minutes per day (study 2) of “on” time without troublesome dyskinesia compared with placebo. These results show that Nourianz led to a much greater increase in “on” time (up to about an hour) compared with placebo.
In the two studies conducted in Japan, people taking Nourianz saw their “on” time increase by about 35 to 40 minutes in one study, and by about 50 minutes in the other study compared to placebo. These results show that Nourianz led to a much greater increase in “on” time compared with placebo.
Your results may differ from what was seen in clinical studies.
What Are Common Side Effects, and How Can I Manage Them?
Some common side effects seen with Nourianz are uncontrolled movements (dyskinesia), dizziness, constipation, nausea, seeing or hearing things that others do not see or hear (hallucinations), and insomnia.
Since Nourianz can cause dyskinesia or make preexisting dyskinesia worse, watch for any changes in your movement and let your health care provider know if you have them. They may decide to adjust the medicines you are taking.
Because Nourianz can make you dizzy, it is important not to drive, operate heavy machinery, or do other potentially dangerous activities until you know how Nourianz affects you. Dizziness can also increase your risk for falls and injuries. Be careful walking, climbing stairs, and doing other physical activities when taking Nourianz.
To minimize constipation while taking Nourianz, make sure you are drinking enough water, eating enough fiber, and regularly exercising. Over-the-counter (OTC) medicines such as stool softeners (docusate) can help soften your stool, making it easier to pass. Laxatives such as milk of magnesia, mineral oil, or bisacodyl can also help stool to pass. Ask your health care provider or pharmacist which laxative product might be best for you. If constipation is frequent or ongoing while taking Nourianz, let your health care provider know.
Since Nourianz has caused serious mental and behavioral problems in some people, you should pay attention to any changes, especially sudden changes in mood, behaviors, thoughts, and feelings. Your family and caregivers should also help you to watch for these changes. Tell your health care provider right away if you experience any changes in mood, personality, or behavior, or if you have been told by others that you have these symptoms after taking Nourianz.
Insomnia is a common side effect. To help lessen the risk of insomnia while taking Nourianz, it is best to take the medicine first thing in the morning.
These are not all of the possible side effects of Nourianz. Contact your health care provider for medical advice about side effects if you are having symptoms that are bothering you. You can also report side effects to the FDA at 800-FDA-1088 (800-332-1088).
What Medicines Can Interact With Nourianz?
Some medicines can interact with Nourianz. Tell your prescriber about all medicines and supplements you take or have recently stopped. This will help them know if your Nourianz dosage needs to be adjusted. If your dose of Nourianz is not adjusted, it may cause more side effects or not work as well. Nourianz can also cause more side effects from other medicines you are taking.
Strong inhibitors or inducers of cytochrome P450 3A4 (CYP3A4): CYP3A4 is an enzyme that processes and removes some medicines from the body. Taking certain medicines that strongly inhibit (decrease the activity of) or induce (increase the activity of) this enzyme can increase the risk of side effects from Nourianz or cause it to not work as well.
Substrates of CYP3A4 or P-glycoprotein: Some medicines may be substrates of CYP3A4 or P-glycoprotein, which means they are metabolized in the body by the same enzymes that metabolize Nourianz. Taking these substrates with Nourianz can increase levels of the substrate in the body, thereby increasing the risk of side effects from the substrate.
This is not a complete list of interactions. Tell your pharmacist or other health care provider about all the prescription or OTC medicines, vitamins/minerals, herbal products, or other supplements you take or have recently taken. This will help them know if there are any interactions with Nourianz.
What Are Other Unique Considerations to Be Aware Of?
People who smoke 20 or more cigarettes per day will need a higher dose of Nourianz, since smoking makes the medicine not work as well. Let your health care provider know if you smoke or use other tobacco products, or if you quit smoking, as they may need to adjust your dose of Nourianz.
Nourianz is not recommended for use during pregnancy. Let your health care provider know if you are pregnant or are planning to become pregnant before starting Nourianz. Birth control is recommended during treatment with Nourianz in women who could become pregnant.
People who take Nourianz can develop intense urges to gamble, increased sexual urges, or other intense urges while taking Nourianz. People can also experience more difficulty controlling their urges. Tell your health care provider right away if you have any increase in urges or have issues with controlling urges after starting Nourianz.
