Semisynthetic human insulin: pharmacokinetics and biological potency in healthy subjects in comparison with highly purified porcine insulin.

Pharmacokinetics and the biological activity of a new semisynthetic human insulin (VEB Berlin-Chemie) were investigated in 5 healthy men. Following an overnight fast, 0.2 IU per kg body weight of human and pork insulins (SNC insulin; VEB Berlin-Chemie) were injected subcutaneously into thigh of each individual at a time interval of 8 days. To assess biological potency of both insulins all subjects were twice connected to the BIOSTATOR. A very similar pattern of serum insulin levels (IRI) was observed following subcutaneous injection of human and pork insulin, marked by a sharp initial increase and maximum values reached after 2.5 hours. 8 hours after the insulin administration the original fasting concentrations were nearly attained. According to C-peptide levels, both insulins inhibited endogenous insulin secretion. Evaluation of insulin action was determined by euglycemic clamp technique, provided by the BIOSTATOR, whose function was transformed into a glucose-controlled dextrose infusion system. The amount of glucose delivered by the system in order to keep the blood glucose steady state concentrations at the fasting level was utilized as the measure of biological activity of the injected insulin on glucose metabolism. Maximum values of glucose infusion were achieved between 3 and 4 hr after injection of human and pork insulins. At the end of the study (8 hr) the glucose administration did not return to its initial rate. After administration of both the human and porcine insulins, a marked but similar decrease of FFA concentrations was observed. This indicated a clear-cut inhibition of lipolysis.(ABSTRACT TRUNCATED AT 250 WORDS)