The present invention relates to antigen-binding compounds that inhibit the enzymatic activity of soluble human CD39. The invention also relates to cells producing such compounds; methods of making such compounds, and antibodies, fragments, variants, and derivatives thereof; pharmaceutical compositions comprising the same; methods of using the compounds to diagnose, treat or prevent diseases, e.g., cancer.本發明係關於抑制可溶性人類CD39之酶活性的抗原結合化合物。本發明亦關於產生此類化合物之細胞;製造此類化合物及其抗體、片段、變異體及衍生物之方法;包含此類化合物之醫藥組合物;使用該等化合物診斷、治療或預防疾病(例如癌症)之方法。