Drug General Information (ID: DDI4CSVMAQ)
Drug Name			Siponimod		Drug Info		Trastuzumab deruxtecan		Drug Info
Drug Type		Small molecule				Monoclonal antibody
Therapeutic Class		Selective Immunosuppressants				Antineoplastics/Her2 Inhibitors

Mechanism of Siponimod-Trastuzumab deruxtecan Interaction (Severity Level: Major)
Additive immunosuppressive effects Click to Show/Hide Mechanism Graph
Drug Name		Siponimod				Trastuzumab deruxtecan
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 Siponimod and Trastuzumab deruxtecan

Recommended Action
Management		The safety and efficacy of siponimod in combination with antineoplastic, immunosuppressive, or immune-modulating agents have not been evaluated. Caution is advised during coadministration and for 3 to 4 weeks after the last dose of siponimod. When switching from drugs with prolonged immune effects to siponimod, the half-life and mode of action of these drugs must be considered to avoid unintended additive immunosuppressive effects while at the same time minimizing risk of disease reactivation.

References
1	Cerner Multum, Inc. "Australian Product Information.".
2	Product Information. Mayzent (siponimod). Novartis Pharmaceuticals, East Hanover, NJ.