Veltuzumab, an anti-CD20 mAb for the treatment of non-Hodgkin's lymphoma, chronic lymphocytic leukemia and immune thrombocytopenic purpura.
Veltuzumab is a humanized, second-generation anti-CD20 mAb currently under development by Immunomedics Inc for the potential treatment of B-cell non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Licensee Nycomed is developing veltuzumab for the potential treatment of rheumatoid arthritis and immune thrombocytopenic purpura (ITP). Veltuzumab contains 90 to 95% human antibody sequences with identical antigen framework regions to epratuzumab (a humanized anti-CD22 mAb) and similar antigen-binding determinants to rituximab (chimeric, anti-CD20 mAb and the first-line treatment of aggressive and indolent NHL). In vitro studies have demonstrated that veltuzumab has enhanced binding avidities and a stronger effect on complement-dependent cytotoxicity compared with rituximab in selected cell lines. In dose-finding phase I/II clinical trials in patients with low-grade NHL, intravenous veltuzumab demonstrated a substantial rate of complete responses in concurrence with shorter and more tolerable infusions compared with rituximab. Currently there has been no evidence of an immune response to repeated administrations, and no serious adverse events related to veltuzumab treatment in patients with NHL. Veltuzumab is undergoing clinical trials using a low-dose subcutaneous formulation in patients with NHL, CLL and ITP. Prospective, randomized clinical trials are needed to clarify the role veltuzumab will play in a market where the therapy of B-cell lymphoproliferative disorders is dominated by rituximab.
Milani
Cannon
C
Brown University Warren Alpert Medical School, The Miriam Hospital, Division of Hematology and Oncology, 164 Summit Avenue, Providence, RI 02906, USA.
Castillo
Jorge
J