Polyamino acid-based particle insulin formulation

A pharmaceutical preparation comprising

• i. Particles based on polyamino acids wherein said polyamino acids
• a. are linear with alpha-peptide linkages,
• b. Comprise at least two types of recurring amino acids which are identical or different from one another, selected from the group consisting of a hydrophobic neutral amino acid (AAN), and an amino acid having an ionisable side chain (AAI), at least portion of the AAI amino acid being in ionised form, and
• c. Have a weight average molar mass Mw of not less than 4000 D;
• and
• ii. An active ingredient selected from the group consisting of insulin, an insulin derivative, an insulin analogue, and combinations of any of the foregoing, wherein the ratio between active ingredient adsorbed to particles and dissolved active ingredient is in the range from about 95:5 to about 5:95.