The present invention relates to a tyrosine kinase inhibitor or a mast cell inhibitor, and in particular masitinib or a pharmaceutically acceptable salt thereof, for the treatment of human rheumatoid arthritis.本發明係關於一種酪胺酸激酶抑制劑或肥大細胞抑制劑及尤其馬塞替尼(masitinib)或其醫藥學上可接受之鹽,其用於治療人類類風濕性關節炎。