MS relapse with poor response to corticosteroids is commonly treated with which adjunctive therapy?

• A. Interferon beta
• B. Plasmapheresis
• C. Cyclophosphamide
• D. Rituximab

Answer: (B)

When a multiple sclerosis relapse does not improve with corticosteroids, an adjunctive therapy that has the strongest evidence for rapid benefit is plasmapheresis. The idea is to remove circulating immune mediators that propagate demyelination during an acute attack. Plasmapheresis taps into the humoral component of the immune response by exchanging plasma and filtering out autoantibodies, immune complexes, and inflammatory cytokines, which can translate into clinical improvement in steroid-refractory relapses.

Interferon beta is a long-term disease-modifying therapy aimed at reducing relapse frequency, not an immediate rescue treatment for an acute relapse. Cyclophosphamide can be considered in very severe, refractory cases but has significant toxicity and is not the standard next step after steroids. Rituximab targets B cells and is used in some MS treatment strategies, but plasmapheresis has more established support specifically for acute steroid-refractory relapses.