The present invention relates to novel antibodies capable of binding specifically to the human insulin-like growth factor I receptor IGF-IR and/or capable of specifically inhibiting the tyrosine kinase activity of said IGF-IR, especially monoclonal antibodies of murine, chimeric and humanized origin, as well as the amino acid and nucleic acid sequences coding for these antibodies. The invention likewise comprises the use of these antibodies as a medicament for the prophylactic and/or therapeutic treatment of cancers overexpressing IGF-IR or any pathology connected with the overexpression of said receptor as well as in processes or kits for diagnosis of illnesses connected with the overexpression of the IGF-IR. The invention finally comprises products and/or compositions comprising such antibodies in combination with anti-EGFR antibodies and/or anti-VEGF antibodies and/or antibodies directed against other growth factors involved in tumor progression or metastasis and/or compounds and/or anti-cancer agents or agents conjugated with toxins and their use for the prevention and/or the treatment of certain cancers.La présente invention concerne de nouveaux anticorps pouvant se fixer de manière spécifique au récepteur du facteur de croissance I semblable à linsuline IGF-IR et/ou pouvant inhiber de manière spécifique lactivité tyrosine kinase dudit IGF-IR, en particulier des anticorps monoclonaux murins, chimériques et humanisés, ainsi que des séquences dacides aminés et dacides nucléiques codant pour lesdits anticorps. Linvention concerne également lutilisation de ces anticorps comme médicaments destinés au traitement prophylactique et/ou thérapeutique des cancers surexprimant lIGF-IR, ou toute autre pathologie associée à la surexpression dudit récepteur, ainsi que dans des méthodes ou des kits de diagnostic de maladies associées à la surexpression de lIGF-IR. Linvention concerne enfin des produits et/ou des compositions contenant lesdits anticorps en combinaison avec des
