Porcine insulin immunogenicity

Human insulin is less immunogenic than bovine, but not porcine, insulin. When changing from animal to human insulin, patients taking <100 units of animal insulin are likely to require 10% less human insulin, and if taking >100 units animal insulin, 25% less human insulin. 

Zwickl CM, Smith HW, Zimmerman JL, Wierda D. Immunogenicity of biosynthetic human LysPro insulin compared to native-sequence human and purified porcine insulins in rhesus monkeys immunized over a 6-week period. Arzneimittelforschung 1995 45 524-528. 

Human insulin (humulin) is prepared by recombinant DNA technology or is synthesized from porcine insulin (enzymatic replacement of the terminal arginine with threonine). Human insulin is preferred to insulin prepared from animals because it is less antigenic. Porcine insulin differs from human insulin by one amino acid (terminal arginine). Bovine insulin is the most immunogenic preparation. A typical dosing... 

Studies in animals, healthy adults, and patients with type I diabetes mellitus have shown human insulin fo have pharmacologic effects identical to those of purified porcine insulin. A comparable pharmacokinetic profile also has been shown. Human insulin, however, administered intramuscularly or intravenously, may have a slightly faster onset and slightly shorter duration of action when compared with purified porcine insulin in patients with diabetes. The usual precautions concerning foxic potentials observed with insulin of animal origin should be followed with rDNA human insulin. As would be expected, the recombinant product has been shown fo be less immunogenic than animal insulins. 

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