What is Sifrol?
Sifrol is a medicine that contains the active substance pramipexole. It comes in the form of white "immediate-release" tablets (round: 0.088 mg, 0.7 mg and 1.1 mg; oval: 0.18 mg and 0.35 mg) and in the form of white "prolonged-release tablets. "(round: 0.26 mg and 0.52 mg; oval: 1.05 mg, 2.1 mg and 3.15 mg). Immediate-release tablets release the active ingredient immediately, while prolonged-release tablets release it slowly over a few hours.
What is Sifrol used for?
Sifrol is used to treat the symptoms of the following diseases:
• Parkinson's disease, which is a progressive mental disorder that causes tremor, slow movement and muscle stiffness; Sifrol can be used alone or in combination with levodopa (another medicine for Parkinson's disease), at any stage of the disease including the later stages when the effect of levodopa becomes less effective;
• moderate to severe restless legs syndrome, a disorder that causes the patient to move their legs uncontrollably to stop the sensations of discomfort, pain or discomfort in the body, especially at night; Sifrol is used when a specific cause of the disorder cannot be identified.
The medicine can only be obtained with a prescription.
How is Sifrol used?
In the treatment of Parkinson's disease, the starting dose is either one 0.088 mg immediate-release tablet three times a day or one 0.26 mg prolonged-release tablet once a day.
Every five to seven days the dose should be increased until symptoms are controlled without causing undesirable effects that cannot be tolerated. The maximum daily dose is three 1.1 mg immediate-release tablets three times a day or one 3.15 mg prolonged-release tablet once daily. Patients can switch from immediate-release to prolonged-release tablets overnight, but the dose may be adjusted according to the patient's response.Sifrol should be given less frequently in patients with kidney problems. If for any reason the treatment is stopped, the dose should be decreased gradually.
In the treatment of restless legs syndrome, Sifrol immediate-release tablets should be taken once a day, two to three hours before bedtime. The recommended starting dose is 0.088 mg but, if necessary, it can be increased every 4-7 days to further reduce symptoms, up to a maximum of 0.54 mg. The patient's response and the need for further treatment should be evaluated after three months. Prolonged-release tablets are not suitable for the treatment of restless legs syndrome.
Sifrol tablets are taken with water, with or without food. The prolonged-release tablets should not be chewed, divided or crushed and should be taken at approximately the same time each day.
For more information, see the package leaflet.
How does Sifrol work?
The active substance in Sifrol, pramipexole, is a dopamine agonist (a substance that mimics the action of dopamine). Dopamine is a messenger substance contained in the brain areas that control movement and coordination. In patients with Parkinson's disease, the dopamine-producing cells begin to die, resulting in a decrease in the amount of dopamine in the brain. Patients therefore lose the ability to reliably control their movements. Pramipexole stimulates the brain just as dopamine would, allowing patients to control their movements and reduce the signs and symptoms of Parkinson's disease, including tremors, stiffness and slowed movement.
The mechanism of action of pramipexole in restless legs syndrome is not yet fully understood. It is believed that this syndrome is caused by alterations in the functioning of dopamine in the brain, which can be corrected with pramipexole.
How has Sifrol been studied?
In Parkinson's disease, Sifrol immediate-release tablets have been studied in five main studies. Four studies compared Sifrol with placebo (a dummy treatment): a study involving 360 patients in advanced stages of the disease, already being treated with levodopa, whose effectiveness was beginning to wear off; three studies involving a total of 886 patients in an early stage of the disease, not yet treated with levodopa. The main measure of effectiveness was the change in the severity of Parkinson's disease. The fifth study compared Sifrol with levodopa in 300 patients with early disease and measured the number of patients with motor symptoms. In support of it. of the use of the prolonged-release tablets, the company presented the results of studies showing that the immediate-release and prolonged-release tablets produced the same levels of the active substance in the body. It also presented studies comparing the two. tablets at early and advanced stages of Parkinson's disease and which examined the transition of patients from immediate-release to prolonged-release tablets.
In restless legs syndrome, Sifrol immediate-release tablets have also been investigated in two main studies. The first compared Sifrol with a placebo for 12 weeks in 344 patients and measured improvement in symptoms. The second included 150 patients who took Sifrol for six months and compared the effects of continuing Sifrol therapy or switching to placebo. The main measure of effectiveness was how long it took before symptoms worsened.
What benefit has Sifrol shown during the studies?
In the study in patients with advanced Parkinson's disease, subjects taking immediate-release Sifrol tablets had greater improvements after 24 weeks of treatment with the maintenance dose than those taking placebo. Similar results were seen in the first three studies in early Parkinson's disease patients, where major improvements were seen after 4 or 24 weeks. Sifrol was also more effective than levodopa in improving motor symptoms in early stage disease. Further studies revealed that the prolonged-release tablets were just as effective as the immediate-release tablets in treating Parkinson's disease. They also showed that patients can safely switch from immediate-release to prolonged-release tablets even though dose adjustments have had to be made in a small number of patients.
In restless legs syndrome, immediate-release sifrol tablets were more effective than placebo in reducing symptoms over a 12-week period, but the difference between placebo and sifrol was greater after four weeks before tapering off. The results of the second study were not sufficient to demonstrate the long-term efficacy of Sifrol.
What is the risk associated with Sifrol?
The most common side effect with Sifrol (seen in more than 1 in 10 patients) is nausea. In patients with Parkinson's disease, the other side effects seen in more than 1 in 10 patients are dizziness, dyskinesia (difficulty carrying movements), sleepiness and hypotension (low blood pressure). For the full list of side effects reported with Sifrol, see the package leaflet.
Sifrol must not be used in people who may be hypersensitive (allergic) to pramipexole or any of the other ingredients.
Why has Sifrol been approved?
The Committee for Medicinal Products for Human Use (CHMP) decided that Sifrol's benefits are greater than its risks for the treatment of the signs and symptoms of idiopathic Parkinson's disease, alone or in combination with levodopa, and in the treatment of Moderate to severe idiopathic restless legs with dosages up to 0.54 mg base. The committee recommended the granting of a marketing authorization for Sifrol.
More information about Sifrol
On 14 October 1997 the European Commission granted Boehringer Ingelheim International GmbH a "Marketing Authorization" for Sifrol, valid throughout the European Union.
The marketing authorization was renewed on 14 October 2002 and 14 October 2007.
For the full version of Siprol's EPAR, click here.
Last update of this summary: 07-2009.
The information on Sifrol - pramipexole published on this page may be out of date or incomplete. For a correct use of this information, see the Disclaimer and useful information page.
