Marizomib for central nervous system-multiple myeloma.

Marizomib, a natural marine product, is an irreversible proteasome inhibitor currently under investigation in relapsed-refractory multiple myeloma (RRMM) and malignant glioma. Central nervous system-multiple myeloma (CNS-MM) is a rare manifestation of extra-medullary disease with few therapeutic options, highlighting the unmet clinical need in these patients. Marizomib demonstrated encouraging activity in RRMM and has emerging clinical activity in glioma, making it a potential CNS-MM therapeutic intervention. Herein, we present two patients with RRMM and CNS involvement who benefited from marizomib-based therapy. These cases provide the first proof of principle for further exploring marizomib in CNS-MM patients.