An insulin composition comprises an insulin analogue and polymer blend. The insulin analogue contains cysteine substitutions at positions B4 and A10 (to form cystine B4-A10), and one or more additional substitutions selected from the group consisting of: a connecting domain of 5-11 amino acids between insulin A- and B domains; a non-beta-branched amino-acid substitution at position A8; a non-beta-branched acidic or polar side chain at position A14; a halogenic modification of PheB24 at the ortho position; and substitution of lysine at position B29 by Glu, Ala, Val, Ile, Leu, amino-propionic acid, amino-butryic acid, or Norleucine. The insulin analogue is compatible with a process of manufacture that includes one or more steps within the temperature range 90-120° C. The encapsulated insulin analogue may optionally contain free PEG or be PEGylated. The insulin analogue-encapsulated polymer blend may be cast as a microneedle patch for topical administration or as micropellets for subcutaneous injection.