Tysabri Dosage/Direction for Use

Therapy is to be initiated and continuously supervised by specialised physicians experienced in the diagnosis and treatment of neurological conditions, in centres with timely access to MRI.
Patients treated with this medicinal product must be given the patient alert card and be informed about the risks of the medicinal product (see also Patient Information Leaflet). After 2 years of treatment, patients should be re-informed about the risks of the medicinal product, especially the increased risk of Progressive Multifocal Leukoencephalopathy (PML), and should be instructed together with their caregivers on early signs and symptoms of PML.
Resources for the management of hypersensitivity reactions and access to MRI should be available.
Some patients may have been exposed to immunosuppressive medicinal products (e.g. mitoxantrone, cyclophosphamide, azathioprine). These medicinal products have the potential to cause prolonged immunosuppression, even after dosing is discontinued. Therefore, the physician must confirm that such patients are not immunocompromised before starting treatment (see also Precautions).
Posology: Tysabri 300 mg is administered by intravenous infusion once every 4 weeks.
Continued therapy must be carefully reconsidered in patients who show no evidence of therapeutic benefit beyond 6 months.
Data on the safety and efficacy of natalizumab at 2 years were generated from controlled, double-blind studies. After 2 years continued therapy should be considered only following a reassessment of the potential for benefit and risk. Patients should be re-informed about the risk factors for PML, like duration of treatment, immunosuppressant use prior to receiving the medicinal product and the presence of anti-John Cunningham virus (JCV) antibodies (see Precautions).
Readministration: The efficacy of re-administration has not been established (for safety see Precautions).
Special populations: Elderly: This medicinal product is not recommended for use in patients aged over 65 due to a lack of data in this population.
Renal and hepatic impairment: Studies have not been conducted to examine the effects of renal or hepatic impairment.
The mechanism for elimination and results from population pharmacokinetics suggest that dose adjustment would not be necessary in patients with renal or hepatic impairment.
Paediatric Population: The safety and efficacy of this medicinal product in children and adolescents up to 18 years have not been established. Currently available data are described in Adverse Reactions and Pharmacology: Pharmacodynamics under Actions.
Method of Administration: This medicinal product is for intravenous use.
For instructions on dilution of the medicinal product before administration, see Special precautions for disposal and other handling under Cautions for Usage.
After dilution (see Special precautions for disposal and other handling under Cautions for Usage), the infusion is to be administered over approximately 1 hour and patients are to be observed during the infusion and for 1 hour after the completion of the infusion for signs and symptoms of hypersensitivity reactions.
After the first 12 intravenous Tysabri doses, patients should continue to be observed during infusion. If the patients have not experienced any infusion reactions, the post dose observation time may be reduced or removed according to clinical judgement.
Tysabri 300 mg concentrate for solution must not be administered as a bolus injection.