Drug Interaction Report

GENERALLY AVOID: The administration of live, attenuated viral or bacterial vaccines during siponimod therapy may be associated with a risk of disseminated infection due to enhanced replication of vaccine virus or bacteria in the presence of diminished immune competence. Siponimod causes reversible sequestration of lymphocytes in lymphoid tissues. A dose-dependent reduction in peripheral lymphocyte count to 20% to 30% of baseline values has been observed, which may increase the risk of infections. Vaccination may also be less effective during and for up to one month after discontinuation of siponimod therapy.

MANAGEMENT: The use of live attenuated vaccines should be avoided during and for up to 4 weeks after siponimod treatment, and siponimod should be paused 1 week prior to and until 4 weeks after a planned vaccination. Patients without a healthcare professional confirmed history of varicella or without documentation of a full course of vaccination against varicella-zoster virus (VZV) should be tested for antibodies to VZV before initiating treatment with siponimod. For antibody-negative patients, a full course of vaccination with varicella vaccine is recommended prior to treatment with siponimod. In patients who have recently been vaccinated, siponimod therapy should be postponed for 4 weeks to allow the full effect of vaccination to occur. Administration of live attenuated vaccines in severely immunocompromised persons is generally considered a contraindication. Current local immunization guidelines and prescribing information for individual vaccines should be consulted for further information.