 For patients with symptomatic gastric extranodal MZL: Helicobacter pylori-negative disease that is de novo or has relapsed following local therapy i.e., surgery or radiotherapy and requires therapy, as assessed by the investigator, or H. pylori-positive disease that has remained stable, progressed, or relapsed following antibiotic therapy and requires therapy, as assessed by the investigator - At least one bi-dimensionally measurable lesion 2 cm in its largest dimension by CT scan or MRI. 