maytansine and Lymphoma--B-Cell

Antibody-drug conjugates (ADCs) are a broad class of molecules comprising of a potent cytotoxic agent conjugated with a monoclonal antibody using a chemically stable linker. By selecting a monoclonal antibody directed against a tumor-specific or tumor-associated antigen, ADCs allow the targeted delivery of highly potent cytotoxic agents that result in unacceptable toxicity when administered as free agents. ADCs are currently being developed for the treatment of a wide variety of tumors. In this review, the current clinical and preclinical status of ADCs for the treatment of B-cell non-Hodgkin's lymphoma and B-cell leukemia will be discussed. ADCs have the potential to alter treatment paradigms for these diseases by providing both increased efficacy and improved safety and tolerability over current chemotherapy-based regimens.

Topics: Antibodies, Monoclonal, Humanized; Antigens, CD; Antineoplastic Agents; Clinical Trials as Topic; Drug Carriers; Humans; Immunotoxins; Inotuzumab Ozogamicin; Leukemia; Lymphoma, B-Cell; Maytansine

SAR3419 is a novel anti-CD19 humanized monoclonal antibody conjugated to a maytansine derivate through a cleavable linker for the treatment of B-cell malignancies. SAR3419 combines the strengths of a high-potency tubulin inhibitor and the exquisite B-cell selectivity of an anti-CD19 antibody. The internalization and processing of SAR3419, following its binding at the surface of CD19-positive human lymphoma cell lines and xenograft models, release active metabolites that trigger cell-cycle arrest and apoptosis, leading to cell death and tumor regression. SAR3419 has also been shown to be active in different lymphoma xenograft models, including aggressive diffuse large B-cell lymphoma, resulting in complete regressions and tumor-free survival. In these models, the activity of SAR3419 compared favorably with rituximab and lymphoma standard of care chemotherapy. Two phase I trials with 2 different schedules of SAR3419 as a single agent were conducted in refractory/relapsed B-cell non-Hodgkin lymphoma. Activity was reported in both schedules, in heavily pretreated patients of both follicular and diffuse large B-cell lymphoma subtypes, with a notable lack of significant hematological toxicity, validating SAR3419 as an effective antibody-drug conjugate and opening opportunities in the future. Numerous B-cell-specific anti-CD19 biologics are available to treat B-cell non-Hodgkin lymphoma, and early phase I results obtained with SAR3419 suggest that it is a promising candidate for further development in this disease. In addition, thanks to the broad expression of CD19, SAR3419 may provide treatment options for B-cell leukemias that are often CD20-negative.

Topics: Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antigens, CD19; Antineoplastic Agents, Phytogenic; Clinical Trials as Topic; Disease Models, Animal; Humans; Immunoconjugates; Leukemia, B-Cell; Lymphoma, B-Cell; Maytansine; Mice; Xenograft Model Antitumor Assays

To determine recommended dose, dose-limiting toxicity, safety profile, pharmacokinetics, preliminary antitumor activity, and exploratory pharmacodynamics of SAR3419, an antibody-drug conjugate targeting CD19, administered alone by intravenous infusion weekly (qw), in a dose-escalation phase I study in patients with refractory/relapsed (R/R) non-Hodgkin lymphoma (NHL).. Patients with R/R CD19(+) B-NHL were treated with escalating doses of SAR3419 repeated qw for eight to 12 doses. On the basis of clinical evidence of late or cumulative toxicities, the study protocol was amended to test an "optimized" administration schedule consisting of four qw doses followed by four biweekly (q2w) doses (qw/q2w) at the recommended dose with the intent of reducing drug accumulation.. Forty-four patients were treated on seven dose levels ranging from 5 to 70 mg/m(2). SAR3419 recommended dose was determined as 55 mg/m(2) qw. Twenty-five patients received the qw/q2w schedule at 55 mg/m(2), which showed an improved safety profile compared with the qw schedule. Antilymphoma activity was observed with both schedules in around 30% of patients with either indolent or aggressive diseases. SAR3419 displayed a long terminal half-life (approximately 7 days) and a low clearance (approximately 0.6 L/d), with no dose effect. The qw/q2w schedule allowed limiting accumulation with a decrease in SAR3419 plasma trough and average concentrations by around 1.4-fold compared with the qw schedule.. While administered weekly, SAR3419 is well tolerated and active. The qw/q2w schedule that shows an improved safety profile and preserves antilymphoma activity is selected for clinical phase II studies.

Topics: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Asthenia; Drug Resistance, Neoplasm; Female; Humans; Infusions, Intravenous; Kidney; Liver; Lymphoma, B-Cell; Male; Maximum Tolerated Dose; Maytansine; Middle Aged; Neoplasm Recurrence, Local; Treatment Outcome

We determine the maximum-tolerated dose (MTD), pharmacokinetics, safety, and preliminary efficacy of SAR3419, an antibody-drug conjugate targeting CD19, in a first-in-man phase I clinical trial in patients with relapsed lymphoma.. Patients with relapsed CD19+ B-cell lymphoma were treated with escalating doses of SAR3419 given by intravenous infusion once every 21 days.. Thirty-nine patients were treated on seven dose levels ranging from 10 to 270 mg/m(2). The median number of prior treatment regimens was four (range, 1 to 9), and 11 patients had prior autologous or allogeneic stem-cell transplantation. The dose-limiting toxicities were reversible severe blurred vision associated with microcystic epithelial corneal changes reported in six patients and neuropathy in one patient. The MTD was 160 mg/m(2) once every 21 days. Hematologic and hepatic toxicities were predominantly grade 1 or 2 in severity. A total of 35 patients have completed at least two cycles of treatment and were evaluable for tumor response. Twenty-six patients (74%) demonstrated reduction in their tumor size; six of those patients achieved partial or complete remissions. Seven (47%) of 15 patients with rituximab-refractory disease demonstrated reduction in their tumor sizes. The pharmacokinetic profile of SAR3419 is characterized by linear kinetics, low clearance from 0.2 to 0.6 L/d/m(2), and an elimination half-life in the range of 3 to 7 days.. Using an every 3-week-schedule of SAR3419 for six cycles, the MTD is 160 mg/m(2). SAR3419 can be safely administered to patients with relapsed B-cell lymphoma and demonstrates promising clinical activity, including patients who were refractory to rituximab.

Topics: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal, Humanized; Drug Administration Schedule; Female; Humans; Immunotoxins; Infusions, Intravenous; Lymphoma, B-Cell; Male; Maximum Tolerated Dose; Maytansine; Middle Aged; Recurrence