RecruitingPhase 2Drug trialRituximab Plus Venetoclax in Front Line Marginal Zone LymphomaThe purpose of this study is to see if the combination of rituximab and venetoclax is effective in treating participants with untreated Marginal Zone Lymphoma (MZL). The names of the study drugs involved in this study are: * Venetoclax (a type of inhibitor) * Rituximab (a type of antibody)