drugs

Trobalt - retigabina

What is Trobalt - retigabine?

Trobalt is a medicine that contains the active substance retigabine. It is available as tablets (round purple: 50 mg; round greens: 100 mg; oblong yellow: 200 mg; oblong greens: 300 mg; oblong violet: 400 mg).

What is Trobalt - retigabine used for?

Trobalt is used for the treatment of partial seizures (seizures) with or without secondary generalization in adults. It is a type of epilepsy in which excessive electrical activity in one part of the brain causes symptoms such as sudden spasmodic movements of a part of the body, problems with hearing, smell or sight, numbness or sudden feelings of fear. Secondary generalization occurs when excessive electrical activity subsequently reaches the whole brain. Trobalt should only be used as an adjunct to other anti-epileptic medicines.

The medicine can only be obtained with a prescription.

How is Trobalt - retigabine used?

Treatment with Trobalt starts with one 100 mg tablet three times a day for a week; then the dose is increased by 50 mg each time with weekly frequency, according to the patient's response. The recommended maintenance dose is between 600 mg a day and a maximum of 1 200 mg a day.

Older patients and those with moderate or severe liver or kidney problems should be given lower doses. For more information on how to use Trobalt, including detailed recommendations for different groups of patients, see the summary of product characteristics (included with EPAR).

How does Trobalt - retigabine work?

The active substance in Trobalt, retigabine, is an anti-epileptic medicine. Epilepsy is caused by excessive electrical activity in the nerve cells of the brain. Trobalt exerts an effect on the potassium channels located on these cells. These channels are pores that allow potassium to enter cells and exit them and play a role in terminating electrical impulses. Trobalt works by keeping the potassium channels open; in this way it interrupts the further transmission of electrical impulses and thus prevents the occurrence of epileptic seizures.

What studies have been carried out on Trobalt - retigabine?

The effects of Trobalt were first tested in experimental models before being studied in humans.

Trobalt has been compared with placebo (a dummy treatment) in three main studies involving a total of 1, 244 patients with seizures not adequately controlled by other antiepileptic medicines. Trobalt at a maintenance dose of 600, 900 or 1 200 mg a day or placebo were taken for 8 weeks in the first study and for 12 weeks in the other two studies. In the first study the main measure of effectiveness was the change in the number of seizures per month. In the other two studies the main measure of effectiveness was the number of patients in which the number of seizures was at least halved.

What benefit has Trobalt - retigabine shown during the studies?

Trobalt was more effective than placebo in reducing the number of seizures. In the first study, Trobalt at 900 mg and 1 200 mg per day was more effective than placebo and reduced the number of seizures per month by 29% and 35% respectively. By contrast, in the placebo group there was a decrease of 13%. The study did not give conclusive results on the effect of Trobalt at 600 mg per day. In the second study, the crises were at least halved in 39% (61 out of 158) of patients treated with Trobalt at 600 mg a day and in 47% (70 of 149) of those who received 900 mg a day compared to 19% (31 of 164) of patients in the placebo group. In the third study, the crises were at least halved in 56% (66 out of 119) of the patients who took Trobalt at 1 200 mg a day, compared with 23% (31 of 137) of patients receiving a placebo.

What are the risks associated with Trobalt - retigabine?

The most common side effects with Trobalt (seen in more than 1 patient in 10) are dizziness, drowsiness and fatigue. For the full list of all side effects reported with Trobalt, see the Package Leaflet.

Trobalt should not be used in people who may be hypersensitive (allergic) to retigabine or any of the other ingredients.

Why has Trobalt - retigabine been approved?

The CHMP decided that Trobalt's benefits are greater than its risks and recommended that it be given marketing authorization.

What measures are being taken to ensure the safe use of Trobalt - retigabina?

The company that makes Trobalt must ensure that doctors who should prescribe it receive a package containing important safety information, including information on some of the less common side effects of the medicine, such as problems with urine excretion, prolonged QT interval (a alteration of the electrical activity of the heart) and visual or auditory hallucinations.

More information on Trobalt - retigabina

On March 28, 2011, the European Commission issued a marketing authorization for Trobalt, valid throughout the European Union, to Glaxo Group Limited. The marketing authorization is valid for five years, after which it can be renewed.

For more information about treatment with Trobalt, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.

Last update of this summary: 02-2011.