Solid compositions having about 150 mg to about 245 mg Fosaprepitant that are stable after storage at about 25° C. for 6 months and processes for preparing solid Fosaprepitant compositions that are stable after long term storage at room temperature. The processes include freezing a Fosaprepitant solution in the primary packaging container at a first freezing temperature; applying vacuum at second temperature that is higher than the freezing temperature; fully stoppering the primary packaging container; and sealing the stoppered primary packaging container.