RESUMEN
Carbonic anhydrase IX (CAIX) is a cell surface glycoprotein that is expressed in many different tumors and yet restricted in normal tissues to the gastrointestinal tract. It is upregulated by hypoxia and correlates with tumor grade and poor survival in several tumor indications. Monoclonal antibodies (mAb) with single digit nanomolar binding affinity for CAIX were derived by panning with the recombinant ectodomain of CAIX against the MorphoSys HUCAL Gold library of human Fabs. Highest affinity Fabs were converted to full-length IgGs and subjected to further characterization based upon their avidity and selectivity for CAIX, their capacity to undergo internalization in CAIX-expressing cell lines, and their selective localization to CAIX-positive human xenografted tumors when administered to mice as fluorescent conjugates. Through this selection process, the 3ee9 mAb was identified, which upon conjugation to monomethyl auristatin E through a self-immolative enzyme-cleavable linker yielded the potent and selective CAIX antibody-drug conjugate CAIX-ADC (BAY 79-4620). In preclinical human xenograft models in mice representing several tumor indications, BAY 79-4620 showed potent antitumor efficacy and in some models showed partial and complete tumor shrinkage even following a single dose. The mechanism of action was shown by histology to involve the sequelae of events typical of antitubulin agents. Efficacy in murine preclinical models correlated semiquantitatively, with CAIX expression levels as determined by immunohistochemistry and ELISA. These preclinical data collectively support the development of BAY 79-4620 for the treatment of cancer patients with CAIX overexpressing tumors.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Antígenos de Neoplasias/metabolismo , Anhidrasas Carbónicas/metabolismo , Inhibidores Enzimáticos/farmacología , Neoplasias/tratamiento farmacológico , Oligopéptidos/farmacología , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/farmacocinética , Antígenos de Neoplasias/inmunología , Western Blotting , Células CHO , Anhidrasa Carbónica IX , Anhidrasas Carbónicas/inmunología , Supervivencia Celular/efectos de los fármacos , Cricetinae , Cricetulus , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/inmunología , Inhibidores Enzimáticos/farmacocinética , Células HCT116 , Células HT29 , Células HeLa , Humanos , Fragmentos Fab de Inmunoglobulinas/genética , Fragmentos Fab de Inmunoglobulinas/inmunología , Fragmentos Fab de Inmunoglobulinas/farmacología , Ratones , Ratones Endogámicos , Ratones Desnudos , Ratones SCID , Neoplasias/enzimología , Neoplasias/patología , Oligopéptidos/metabolismo , Oligopéptidos/farmacocinética , Biblioteca de Péptidos , Distribución Tisular , Resultado del Tratamiento , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Inhibitors of the MAP kinase p38 provide a novel approach for the treatment of osteoporosis, inflammatory disorders, and cancer. We have identified N-(3-tert-butyl-1-methyl-5-pyrazolyl)-N'-(4-(4-pyridinylmethyl)phenyl)urea as a potent and selective p38 kinase inhibitor in biochemical and cellular assays. This compound is orally active in two acute models of cytokine release (TNF-induced IL-6 and LPS-induced TNF) and a chronic model of arthritis (20-day murine collagen-induced arthritis).