Phase 2, open-label, non-randomized, monotherapy study to evaluate the safety and efficacy of ibrutinib in subject with relapsed/refractory Marginal Zone Lymphoma (MZL).

Ibrutinib is a first-in-class, potent, orally administered covalent inhibitor of Bruton's tyrosine kinase (BTK). Inhibition of BTK blocks downstream B-cell receptor (BCR) signaling pathways and thus prevents B-cell proliferation. In vitro, ibrutinib inhibits purified BTK and selected members of the kinase family with 10-fold specificity compared with non-BTK kinases. Phase 1 and 2 studies of ibrutinib in B-cell malignancies demonstrate modest toxicity and significant single agent activity in a variety of B-cell malignancies, including NHL.

Key Inclusion criteria:

• Histologically documented marginal zone lymphoma including splenic, nodal, and extranodal sub-types; subjects with splenic MZL must have an additional measurable lesion, nodal or extranodal, as described in inclusion criteria 5
• Previously received one or more lines of therapy including at least one CD20-directed regimen (either as monotherapy or as chemoimmunotherapy) with documented failure to achieve at least PR or documented PD after, the most recent systemic treatment regimen
• Men and women ≥18 years of age
• ECOG performance status of ≤2
• ≥1 measurable lesion site on CT scan (>1.5 cm in longest dimension). Lesions in anatomical locations (such as extremities or soft tissue lesions) that are not well visualized by CT may be measured by MRI instead. (Subjects with spleen-only disease are considered as not having measurable disease.)
• Life expectancy of >3 months, in the opinion of the investigator

Key Exclusion criteria:

• Medically apparent CNS lymphoma or leptomeningeal disease
• History of other malignancies except adequately treated non melanoma skin cancer, curatively treated in-situ cancer, or other solid tumors curatively treated with no evidence of disease for ≥2 years
• History of allogeneic stem-cell (or other organ) transplantation
• Any chemotherapy, anticancer antibodies, or other systemic anticancer therapy within 21 days of the first dose of study drug
• Any external beam radiation therapy within 6 weeks prior to the first dose of the study drug
• Concurrent use of warfarin or other vitamin K antagonists
• Concurrent use of a strong CYP3A inhibitor. Subjects who have received a strong CYP3A inhibitor prior to entering the study must have discontinued therapy for at least 5 half lives of the prohibited medication.
• Recent infection requiring IV anti-infective treatment that was completed ≤14 days before the first dose of study drug
• Unresolved toxicities from prior anti-cancer therapy, defined as having not resolved to CTCAE Grade 0 or 1, or to the levels dictated in the eligibility criteria with the exception of alopecia
• Inadequate organ function as defined on laboratory tests