MATRIX Provides ‘Excellent, Long-Lasting Survival’ in Primary CNS Lymphoma

A 4-drug regimen improves long-term survival in patients with primary central nervous system (CNS) lymphoma, according to data presented at the European Hematology Association (EHA) 2021 Virtual Congress.¹

The regimen, which consists of methotrexate, cytarabine, rituximab, and thiopeta (MATRIX), previously demonstrated efficacy in the phase 2 IELSG32 trial (ClinicalTrials.gov Identifier: NCT01011920).²

At EHA 2021, Gerald Illerhaus, MD, of Klinikum Stuttgart in Germany, presented long-term data from IELSG32.

The trial enrolled HIV-negative adults, ages 18 to 70 years, who had not previously been treated for primary CNS lymphoma. Patients were randomly assigned to receive methotrexate and cytarabine (arm A); methotrexate, cytarabine, and rituximab (arm B); or MATRIX (arm C).

Patients who responded to treatment or had stable disease were further randomly assigned to receive consolidation with whole-brain radiotherapy (WBRT) or autologous stem cell transplant (ASCT).

Overall, 219 patients were randomly assigned to arm A (n = 75), arm B (n = 69), or the MATRIX arm (n = 75). In the second randomization, 59 patients were assigned to WBRT and 59 to ASCT.

After induction, response rates were superior with MATRIX. The complete response rate was 23% in arm A, 30% in arm B, and 49% with MATRIX (P values: A vs B =.29, A vs MATRIX =.0007, B vs MATRIX = .02).

Overall response rates were 54% in arm A, 73% in arm B, and 86% with MATRIX (P values: A vs B =.01, A vs MATRIX =.00001, B vs MATRIX = .05).

At a median follow-up of 88 months, survival results were superior with MATRIX.

The progression-free survival (PFS) was significantly better in the MATRIX arm compared with arm A (hazard ratio [HR], 0.41; P =.00001) and in the MATRIX arm compared with arm B (HR, 0.63; P =.01).

The overall survival (OS) was significantly better in the MATRIX arm compared with arm A (HR, 0.42; P =.00005) and in the MATRIX arm compared with arm B (HR, 0.66; P =.044).

Patients who received MATRIX and consolidation had a 7-year OS rate of 70%. PFS and OS results were not significantly different between the WBRT and ASCT arms.

“The MATRIX regimen was associated with an excellent long-lasting survival in patients below 70 years,” Dr Illerhaus said.

Disclosures: The presenter declared affiliations with Celgene and Riemser. 

Reference

1. Illerhaus G, Cwynarski K, Pulczynski E, et al. Matrix followed by autologous transplant is associated with excellent survival and neurotolerability in primary CNS lymphoma: results of the IELSG32 trial at a median follow-up of 88 months. Paper presented at: European Hematology Association 2021 Virtual Congress; June 2021; Abstract S219.
2. Ferreri AJM, Cwynarski K, Pulczynski E et al. Chemoimmunotherapy with methotrexate, cytarabine, thiotepa, and rituximab (MATRix regimen) in patients with primary CNS lymphoma: results of the first randomisation of the International Extranodal Lymphoma Study Group-32 (IELSG32) phase 2 trial. Lancet Haematol. 2016 May;3(5):e217-27. doi:10.1016/S2352-3026(16)00036-3

This article originally appeared on Cancer Therapy Advisor