The present invention relates to formulation of antibodies. The invention relates in particular to pharmaceutical compositions comprising an antibody molecule of the IgG1 isotype having a mutation in the Fc region that enhances clustering of IgG molecules after cell-surface antigen binding.本發明關於抗體調製。本發明特別關於包含IgG1同型之抗體分子的醫藥組成物,該IgG1同型之抗體分子在Fc區具有促進IgG分子在與細胞表面抗原結合後叢聚的突變。