A stable lyophilized protein formulation is described which can be
reconstituted with a suitable diluent to generate a high protein
concentration reconstituted formulation which is suitable for
subcutaneous administration. For example, anti-IgE and anti-HER2 antibody
formulations have been prepared by lyophilizing these antibodies in the
presence of a lyoprotectant. The lyophilized mixture thus formed is
reconstituted to a high protein concentration without apparent loss of
stability of the protein.