Natalizumab
Examples
Natalizumab
Indications
Multiple sclerosis
It is licensed for use in patients with highly active relapsing-remitting multiple sclerosis despite treatment with interferon beta or those with rapidly evolving severe relapsing-remitting multiple sclerosis.
Contraindications
Caution
- Prior treatment with immunosuppressants
- Hepatic impairment
Contraindications
- Progressive multifocal leucoencephalopathy
- Active infection
- Concurrent use of interferon beta or glatiramer acetate
- Immunosuppression
- Active malignancy
Mechanism
Natalizumab is an anti-α4-integrin antibody. It acts by inhibiting leucocyte migration into inflamed tissue to reduce the inflammatory response.
Administration
Intravenous infusion every 4 weeks.
Adverse Reactions
- Infusion reaction
- Hypersensitivity
- Infection, particularly UTI
- Hepatic toxicity
- Progressive multifocal leucoencephalopathy which is due to the JC virus which is commonly latent in the population. This infection can be 'reactivated' in immunosupressed patients and has occurred in those on Natalizumab. It is therefore recommended that an MRI be done before treatment commences and annually afterwards (to look for changes associated with PML) and a serum JC virus antibody. If a patient has been exposed to JC virus they have an increased risk of PML and can make an informed choice of whether they wish to commence it.
- Antibodies to natalizumab may be formed
Interactions
No specific interactions are noted, however it may be wise to avoid the use of live vaccines with natalizumab.
Education
Patients should be warned about potential side effects and to watch out for the development of infection. They should also be specifically informed about the risk of PML and the signs/symptoms it presents with.
Pharmacokinetics
Natalizumab has a long half life and may be active up to 12 weeks after administration.
