What is the difference between Tysabri and Copaxone?
Although there have been no head to head comparisons of Tysabri and Copaxone, a simple comparison of clinical trial results in relapsing MS patients suggests that Tysabri is far more effective than Copaxone as a treatment for MS.
For instance in relapsing remitting MS patients,
1. Tysabri decreases relapse rates by 67 % whereas Copaxone decreases relapses by 29 %
2. Tysabri decreases disability progression by 42 % whereas Copaxone has not been demonstrated to decrease disability progression
Tysabri is a monoclonal antibody that blocks an adhesion molecule required for immune cells to gain access to the brain; it is given once every 28 days by IV infusion.
Copaxone is a subcutaneous injection self administered daily or three times a week. The exact mechanism of action is unknown, but it is believed that it may alter or modulate immune responses in people with MS.
There are few if any long term risks of treatment with Copaxone although the injections often hurt and cause reactions under the skin. Long term treatment may result in loss of subcutaneous tissue at injections sites called lipoatrophy.
Tysabri is associated with hypersensitivity reactions during the infusions in about 5 % of patients. These reactions almost always occur between the 2nd and 6th infusion. Rarely, patients can develop a severe brain infection called progressive multifocal leukoencephalopathy (PML) , most commonly after more than 2 years of therapy. The risk of PML is very low in patients who are JC virus antibody negative and have never received immunosuppressive treatment (see prior blogs on tysabri therapy)
Revere (Rip) Kinkel MD
Director of the Multiple Sclerosis Program
Professor of Clinical Neurosciences
University of California San Diego