Bendamustine and Rituximab (BR) as Induction and Maintenance in Relapsed and Refractory Chronic Lymphocytic Leukemia

Study of Bendamustine and Rituximab as Induction Immunochemotherapy Followed by Maintenance Bendamustine and Rituximab in Relapsed and Refractory B-cell Chronic Lymphocytic Leukemia (CLL)

CLL is an incurable disease with conventional chemotherapy. In the absence of TP53 disruption, a chemoimmunotherapy (CIT) regimen is recommended as front-line and second-line treatment in those patients who attained a long progression-free survival (PFS) with the previous regimen. Bendamustine and rituximab (BR) is one of the most widely adopted CIT regimens, including second-line treatment. Unfortunately, durations of remission following BR combination therapy tend to be short in patients with heavily pre-treated disease or who have already received rituximab. The incorporation of a maintenance following induction chemotherapy to overcome the shorter remission durations in this population is a reasonable option.

Inclusion Criteria:

• Confirmed diagnosis of CD20-positive CLL that meets the iwCLL criteria (Hallek et al, 2008).
• Relapsed or refractory status of disease after at least one prior chemotherapy regimen.
• ECOG performance status of 0-2 at study entry
• Patients have not received prior therapy with bendamustine
• Prior therapy with rituximab is permitted, even in the setting of rituximab refractory disease.

For inclusion in the research part of maintenance therapy (phase B):

• At least a partial response (PR or better; Hallek et al, 2008) must be achieved after induction of BR (phase A)

Exclusion Criteria:

• Any serious medical condition, laboratory abnormality, or psychiatric illness that would prevent the subject from signing the informed consent document or complying with the protocol treatment.
• Pregnant or breast-feeding females.
• Known to be positive for human immunodeficiency virus (HIV) or infectious hepatitis (type B or C).
• Patients are not eligible if there is a prior history or current evidence of central nervous system or leptomeningeal involvement.
• Richter syndrome or chronic prolymphocytic leukemia.
• Uncontrolled autoimmune hemolytic anemia or thrombocytopenia.
• Concurrent use of other anti-cancer agents or treatments.
• Laboratory test results within these ranges: ANC ≤ 1000/μL, Platelet count ≤ 75,000/μL.
• Total bilirubin Total bilirubin ≥ 2X upper limit laboratory normal (ULN). Patients with non-clinically significant elevations of bilirubin due to Gilbert's disease are not required to meet these criteria.
• Serum transaminases AST (SGOT) and ALT (SGPT) ≥ 3 x ULN, and/or serum alkaline phosphatase ≥ 5 X ULN.
• New York Heart Association class 3-4 heart failure.