This is a prospective, phase II study on the activity and tolerability of high dose (2 g/day) oral clarithromycin for the treatment of relapsed or refractory extranodal marginal zone lymphoma.

A 6-month regimen of oral clarithromycin has been associated with a 35% ORR in patients with relapsed/refractory marginal zone B-cell lymphoma. Responses were more common among patients with conjunctival lymphoma. This could be explained at least in part by the elimination of clarithromycin by tears, suggesting that a higher tumor bioavailability of this antibiotic could result in a higher activity. Thus, a higher dose of clarithromycin could be associated with a higher tumor bioavailability in tissues other than the conjunctiva.

Inclusion Criteria:

• histologically confirmed diagnosis of extranodal extra-gastric marginal zone cell B lymphoma or gastric Helicobacter pylori positive lymphoma refractory to conventional antibiotic therapy, or H. pylori negative
• at least one measurable lesion
• relapsed or refractory lymphoma after systemic (chemotherapy, immunotherapy, antibiotic) or local (surgery or radiation) therapy
• ECOG PS \