about 5.1 to about 7.0, about 5.1 to about 6.9, about 5.1 to about 6.8, about 5.1 to about 6.7, about 5.1 to about 6.6, about 5.1 to about 6.5, about 5.1 to about 6.4, about 5.1 to about 6.3, about 5.1 to about 6.2, about 5.1 to about 6.1, about 5.1 to about 6.0, about 5.1 to about 5.9, about 5.1 to about 5.8, about 5.1 to about 5.7, about 5.1 to about 5.6, about 5.1 to about 5.5, about 5.1 to about 5.4, about 5.1 to about 5.3, about 5.2 to about 7.0, about 5.2 to about 6.9, about 5.2 to about 6.8, about 5.2 to about 6.7, about 5.2 to about 6.6, about 5.2 to about 6.5, about 5.2 to about 6.4, about 5.2 to about 6.3, about 5.2 to about 6.2, about 5.2 to about 6.1, about 5.2 to about 6.0, about 5.2 to about 5.9, about 5.2 to about 5.8, about 5.2 to about 5.7, about 5.2 to about 5.6, about 5.2 to about 5.5, about 5.2 to about 5.4, about 5.3 to about 7.0, about 5.3 to about 6.9, about 5.3 to about 6.8, about 5.3 to about 6.7, about 5.3 to about 6.6, about 5.3 to about 6.5, about 5.3 to about 6.4, about 5.3 to about 6.3, about 5.3 to about 6.2, about 5.3 to about 6.1, about 5.3 to about 6.0, about 5.3 to about 5.9, about 5.3 to about 5.8, about 5.3 to about 5.7, about 5.3 to about 5.6, about 5.3 to about 5.5, about 5.4 to about 7.0, about 5.4 to about 6.9, about 5.4 to about 6.8, about 5.4 to about 6.7, about 5.4 to about 6.6, about 5.4 to about 6.5, about 5.4 to about 6.4, about 5.4 to about 6.3, about 5.4 to about 6.2, about 5.4 to about 6.1, about 5.4 to about 6.0, about 5.4 to about 5.9, about 5.4 to about 5.8, about 5.4 to about 5.7, about 5.4 to about 5.6, about 5.5 to about 7.0, about 5.5 to about 6.9, about 5.5 to about 6.8, about 5.5 to about 6.7, about 5.5 to about 6.6, about 5.5 to about 6.5, about 5.5 to about 6.4, about 5.5 to about 6.3, about 5.5 to about 6.2, about 5.5 to about 6.1, about 5.5 to about 6.0, about 5.5 to about 5.9, about 5.5 to about 5.8, about 5.5 to about 5.7, about 5.6 to about 7.0, about 5.6 to about 6.9, about 5.6 to about 6.8, about 5.6 to about 6.7, about 5.6 to about 6.6, about 5.6 to about 6.5, about 5.6 to about 6.4, about 5.6 to about 6.3, about 5.6 to about 6.2, about 5.6 to about 6.1, about 5.6 to about 6.0, about 5.6 to about 5.9, about 5.6 to about 5.8, about 5.7 to about 7.0, about 5.7 to about 6.9, about 5.7 to about 6.8, about 5.7 to about 6.7, about 5.7 to about 6.6, about 5.7 to about 6.5, about 5.7 to about 6.4, about 5.7 to about 6.3, about 5.7 to about 6.2, about 5.7 to about 6.1, about 5.7 to about 6.0, about 5.7 to about 5.9, about 5.8 to about 7.0, about 5.8 to about 6.9, about 5.8 to about 6.8, about 5.8 to about 6.7, about 5.8 to about 6.6, about 5.8 to about 6.5, about 5.8 to about 6.4, about 5.8 to about 6.3, about 5.8 to about 6.2, about 5.8 to about 6.1, about 5.8 to about 6.0, about 5.9 to about 7.0, about 5.9 to about 6.9, about 5.9 to about 6.8, about 5.9 to about 6.7, about 5.9 to about 6.6, about 5.9 to about 6.5, about 5.9 to about 6.4, about 5.9 to about 6.3, about 5.9 to about 6.2, about 5.9 to about 6.1, about 6.0 to about 7.0, about 6.0 to about 6.9, about 6.0 to about 6.8, about 6.0 to about 6.7, about 6.0 to about 6.6, about 6.0 to about 6.5, about 6.0 to about 6.4, about 6.0 to about 6.3, about 6.0 to about 6.2, about 6.1 to about 7.0, about 6.1 to about 6.9, about 6.1 to about 6.8, about 6.1 to about 6.7, about 6.1 to about 6.6, about 6.1 to about 6.5, about 6.1 to about 6.4, about 6.1 to about 6.3, about 6.2 to about 7.0, about 6.2 to about 6.9, about 6.2 to about 6.8, about 6.2 to about 6.7, about 6.2 to about 6.6, about 6.2 to about 6.5, about 6.2 to about 6.4, about 6.3 to about 7.0, about 6.3 to about 6.9, about 6.3 to about 6.8, about 6.3 to about 6.7, about 6.3 to about 6.6, about 6.3 to about 6.5, about 6.4 to about 7.0, about 6.4 to about 6.9, about 6.4 to about 6.8, about 6.4 to about 6.7, 

about 6.4 to about 6.6, about 6.5 to about 7.0, about 6.5 to about 6.9, about 6.5 to about 6.8, about 6.5 to about 6.7, about 6.6 to about 7.0, about 6.6 to about 6.9, about 6.6 to about 6.8, about 6.7 to about 7.0, about 6.7 to about 6.9, or about 6.8 to about 7.0, or about 5.0, about 5.1, about 5.2, about 5.3, about 5.4, about 5.5, about 5.6, about 5.7, about 5.8, about 5.9, about 6.0, about 6.1, about 6.2, about 6.3, about 6.4, about 6.5, about 6.6, about 6.7, about 6.8, about 6.9, or about 7.0). In one embodiment, the pH is between 5.5 and 7.0. In another embodiment, the pH is between 6.0 and 6.5. In another embodiment, the pH is about 6.2. 

[0129] A person of ordinary skill in the art will understand that the pH can be adjusted as necessary to maximize stability and solubility of aflibercept in a particular formu› lation. For example, a strong acid ( e.g. HCl) or a strong base (NaOH) can be added to a formulation to adjust the pH down or up. Such adjustment to a target pH can be made in buffer-free formulations and such formulations are still considered buffer-free 

[0130] C. Excipients Suitable for Use in Aflibercept For› mulations 

[0131] Excipients include components of a pharmaceuti› cal formulation other than the active ingredient and are typically added during formulation development for a spe› cific purpose, such as to stabilize the polypeptide while in solution, change viscosity of the formulation, adjust tonicity, and confer other desired properties to the formulation. Excipients are well known in the art and are manufactured by known methods and available from commercial suppli› ers. Excipients may include, for example, tonicity modifiers ( e.g., any of the exemplary tonicity modifiers described herein), stabilizers ( e.g., any of the exemplary stabilizers described herein), salts (e.g., any of the exemplary salts described herein), chelating agents (e.g., any of the exem› plary chelating agents described herein), sacrificial additives and surfactants ( e.g., any of the exemplary additives or surfactants described herein), and miscellaneous excipients such as ammonium sulfate, magnesium sulfate, sodium sulfate, trimethylamine N-oxide, betaine, metal ions (e.g., zinc, copper, calcium, manganese, and magnesium), CHAPS, monolaurate, 2-O-beta-mannoglycerate, and the like. In one embodiment, the concentration of an excipient in a formulation of the invention is between about 0.001 to 30 weight percent (e.g., about 0.001 to about 28 weight percent, about 0.001 to about 26 weight percent, about 0.001 to about 24 weight percent, about 0.001 to about 22 weight percent, about 0.001 to about 20 weight percent, about 0.001 to about 18 weight percent, about 0.001 to about 16 weight percent, about 0.001 to about 14 weight percent, about 0.001 to about 12 weight percent, about 0.001 to about 10 weight percent, about 0.001 to about 9 weight percent, about 0.001 to about 8 weight percent, about 0.001 to about 7 weight percent, about 0.001 to about 6 weight percent, about 0.001 to about 5 weight percent, about 0.001 to about 4.5 weight percent, about 0.001 to about 4.0 weight percent, about 0.001 to about 3.5 weight percent, about 0.001 to about 3.0 weight percent, about 0.001 to about 2.5 weight percent, about 0.001 to about 2.0 weight percent, about 0.001 to about 1.5 weight percent, about 0.001 to about 1.0 weight percent, about 0.001 to about 0.5 weight percent, about 0.001 to about 0.1 weight percent, about 0.001 to about 0.01 weight percent, about 0.01 to about 30 weight percent, about 0.01 to about 28 weight percent, about 0.01 to about 26 weight percent, about 0.01 to about 24 weight percent, about 

