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Another treatment option for patients with relapsing-remitting multiple sclerosis became available on December 4 with the launch of glatiramer acetate (Copaxone) (see p866). |  Glatiramer: a new treatment option for MS patients |
The drug is thought to limit damage to myelin by activating antigen-specific T-suppressor cells, which reduce the inflammation in the central nervous system that occurs in patients with multiple sclerosis.
The recommended adult dose of the drug is 20mg injected subcutaneously daily. Each pack, which contains 28 vials of glatiramer, 28 vials of water for injections, needles and syringes costs £510.14. Teva, co-marketer of the product with Aventis Pharma, says that this equates to an average annual cost of £6,650 per patient.
Glatiramer has been included in the National Institute for Clinical Excellence review of treatments for multiple sclerosis. The NICE's final consultation document is expected to be released in January next year.
In a phase III controlled trial of glatiramer, 251 patients were given either 20mg glatiramer or placebo for up to 35 months. A 32 per cent reduction in relapse rate was seen in the glatiramer group compared with those receiving placebo. Nearly 34 per cent of treated patients were relapse-free over the entire study, compared with 25 per cent on placebo. In addition, the median time to first relapse was 287 days for the glatiramer group compared with 198 days for those taking placebo.
In an open-label extension of this trial, patients received the drug for a total of up to five and a half years. The company says that the reduction in annual relapse rate during this time was maintained.
The drug has also been shown to reduce the number of brain lesions observable by magnetic resonance imaging. This indicates reduced disease activity, Teva says.
Dr Jerry Wolinsky (University of Texas, Houston), one of the lead trialists of glatiramer told The Journal at the launch meeting that a dose-finding study (the Coral trial) had begun on a slow-release tablet formulation of glatiramer. Patients were being recruited and randomised into one of three groups - placebo, 5mg glatiramer or 50mg glatiramer. The results of this trial should become available towards the end of next year, he said.
In addition, trials are ongoing to test the efficacy of glatiramer in the progressive forms of multiple sclerosis.
Dr Phil Wood (medical director, Teva Pharmaceuticals) told The Journal at the launch meeting that the most common side effect of glatiramer was injection site reaction, which could present as local irritation, burning or swelling. Some patients might suffer regional lymph node enlargement. In addition, he said, a transient systemic reaction had been identified in about 15 per cent of patients injecting the drug and 3 per cent of those using placebo. This took the form of flushing, tachycardia, shortness of breath and anxiety. The reason for this reaction was not known but it was not thought to be allergic or cardiac in origin.