Drug General Information (ID: DDI8C0XBJ1)
Drug Name			Natalizumab		Drug Info		Mercaptopurine		Drug Info
Drug Type		Monoclonal antibody				Small molecule
Therapeutic Class		Selective Immunosuppressants				Antineoplastics

Mechanism of Natalizumab-Mercaptopurine Interaction (Severity Level: Major)
Additive immunosuppressive effects Click to Show/Hide Mechanism Graph
Drug Name		Natalizumab				Mercaptopurine
Mechanism		Immunosuppressive effects				Immunosuppressive effects
Key Mechanism Factor 1
		Factor Name		Immunosuppressive effects
		Factor Description		Immunosuppression is when your immune system is not functioning as it should. The immune system is made up of cells, tissues and organs that help the body fight off infections. If the immune system is suppressed, an infection that your body was able to control may become serious or even fatal.
Mechanism Description		Additive immunosuppressive effects by the combination of Natalizumab and Mercaptopurine

Recommended Action
Management		The safety and efficacy of natalizumab in combination with immunosuppressant, immunomodulating, antineoplastic or other myelosuppressive agents have not been established. In general, patients receiving chronic therapy with such agents should not be treated with natalizumab due to potentially increased risk of PML and other serious infections. Typical symptoms associated with PML are diverse, progress over days to weeks, and include progressive weakness on one side of the body, clumsiness of limbs, disturbance of vision, and changes in thinking, memory, and orientation leading to confusion and personality changes. Due to the long half-life of natalizumab, immune effects are possible for up to 2 to 3 months following its discontinuation.

References
1	Product Information. Tysabri (natalizumab). Elan Pharmaceutical/Athena Neurosciences Inc, South San Francisco, CA.