Authenticity and purity of human insulin (recombinant DNA).

A summary of the exhaustive analyses of human insulin (recombinant DNA) shows chemical, structural, and biologic equivalence to pancreatic human insulin. The high degree of purity accounts for its lack of pyrogenicity and immunogenic contamination. Human insulin from both the proinsulin and chain combination methods is essentially identical. The role of proinsulin as an alternate route to human insulin, and as a new treatment for diabetes when used alone or in combination with human insulin or connecting peptide, warrants further investigation.