This document relates to a composition comprising fosaprepitant, or a pharmaceutically acceptable salt thereof, and human serum albumin, wherein the fosaprepitant, or a pharmaceutically acceptable salt thereof, and the human serum albumin in the composition have a ratio by weight from about 1:0.1 to about 1:500. This document also relates to a composition comprising aprepitant and human serum albumin, wherein the aprepitant and the human serum albumin in the composition have a ratio by weight from about 1:80 to about 1:1000. This document also relates to a composition comprising fosaprepitant, or a pharmaceutically acceptable salt thereof, aprepitant and human serum albumin.