MATRix

The MATRix regimen is a high-dose chemoimmunotherapy protocol primarily utilized as the induction phase for fit patients with newly diagnosed primary central nervous system lymphoma (PCNSL). It consists of four agents: methotrexate (antimetabolite), cytarabine (antimetabolite), thiotepa (alkylating agent), and rituximab (anti-CD20 monoclonal antibody). The regimen was established following the IELSG32 randomized phase 2 trial, which demonstrated superior complete remission rates and survival outcomes compared to methotrexate-cytarabine combinations with or without rituximab. Its mechanism involves a multi-pronged attack on malignant B-cells: methotrexate and cytarabine inhibit DNA synthesis by interfering with folate metabolism and DNA polymerase activity, respectively; thiotepa causes DNA cross-linking through alkylation; and rituximab induces antibody-dependent cellular cytotoxicity and complement-mediated lysis of CD20-positive cells. This combination is designed to maximize blood-brain barrier penetration and systemic efficacy.

Brand names

MATRix

Other names

MATRix regimenmethotrexate + cytarabine + thiotepa + rituximab