maytansine and Lymphoma--Non-Hodgkin

The identification of epidermal growth factor receptor mutations and anaplastic lymphoma kinase rearrangements and the development of targeted therapy for patients with these molecular alterations has been a tremendous advance in the treatment of advanced stage or metastatic non-small cell lung cancer (NSCLC). However, the majority of patients with advanced stage NSCLC will not have one of these molecular alterations and will receive chemotherapy as their primary therapy. Chemotherapy remains a critical component of therapy for resected and locally advanced NSCLC, as well as for patients with limited-stage and extensive stage small cell lung cancer (SCLC). A significant unmet need exists to develop novel chemotherapy agents and to improve the efficacy and toxicity of currently available agents. Several novel formulations of currently available chemotherapy agents are in development for NSCLC and SCLC. Antibody conjugates are therapeutic agents that employ a tumor-specific monoclonal antibody conjugated to a cytotoxic or radionuclide agent. After the monoclonal antibody binds to the tumor antigen, these agents are internalized, and the link between the antibody and the therapeutic agent is dissolved and the cytotoxic agent is release intracellularly. This enhanced delivery of chemotherapy to malignant tissues has the potential to improve efficacy and reduce toxicity. Antibody conjugates to therapeutic agents are currently available for other malignancies and are in development for NSCLC and SCLC.

Topics: Antibodies, Monoclonal; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Hodgkin Disease; Humans; Liposomes; Lung Neoplasms; Lymphoma, Non-Hodgkin; Maytansine; Small Cell Lung Carcinoma

Antibody-drug conjugates (ADC), potent cytotoxic drugs covalently linked to antibodies via chemical linkers, provide a means to increase the effectiveness of chemotherapy by targeting the drug to neoplastic cells while reducing side effects. Here, we systematically examine the potential targets and linker-drug combinations that could provide an optimal ADC for the treatment for non-Hodgkin's lymphoma. We identified seven antigens (CD19, CD20, CD21, CD22, CD72, CD79b, and CD180) for potential treatment of non-Hodgkin's lymphoma with ADCs. ADCs with cleavable linkers mediated in vivo efficacy via all these targets; ADCs with uncleavable linkers were only effective when targeted to CD22 and CD79b. In target-independent safety studies in rats, the uncleavable linker ADCs showed reduced toxicity, presumably due to the reduced release of free drug or other toxic metabolites into the circulation. Thus, our data suggest that ADCs with cleavable linkers work on a broad range of targets, and for specific targets, ADCs with uncleavable linkers provide a promising opportunity to improve the therapeutic window for ADCs in humans.

Topics: Animals; Antigens, CD; Antineoplastic Agents; B-Lymphocytes; Cross-Linking Reagents; Female; Immunotoxins; Lymphoma, Non-Hodgkin; Maytansine; Mice; Mice, Inbred ICR; Mice, SCID; Oligopeptides; Rats; Sulfhydryl Compounds; Xenograft Model Antitumor Assays