Efficacy and Safety of Ibrutinib in Combination with Rituximab As Frontline Treatment for Indolent Clinical Forms of Mantle Cell Lymphoma (MCL): Preliminary Results of Geltamo IMCL-2015 Phase II Trial

Background: MCL is a heterogeneous disease and the existence of indolent clinical forms is increasingly recognized although their biological ground is not fully elucidated. The aim of this study was to propose a frontline tailored treatment for indolent clinical forms with a chemo-free regimen, ibrutinib in combination with rituximab. In addition, an extensive genomic study was associated to gain biological insight into these clinical forms. Methods: This is a multicenter single-arm, open-label, phase II study with a two-stage design conducted in 14 Spanish GELTAMO sites (NCT02682641). Centralized histology, PET-CT review as well as minimal residual disease (MRD) studies (qPCR and NGS in peripheral blood [PB] and bone marrow [BM]) and biological studies are conducted. A total of 50 previously untreated MCL patients with indolent clinical forms are planned to be recruited, defined by the following criteria: no symptoms attributable to MCL, ECOG 0-1, stable disease without therapy need at least for 3 months, non-blastoid variants, Ki-67