Diabetes Care, Vol 19, Issue 12 1437-1440, Copyright © 1996 by American Diabetes Association
Injection site effects on the pharmacokinetics and glucodynamics of insulin lispro and regular insulin
EW ter Braak, JR Woodworth, R Bianchi, B Cerimele, DW Erkelens, JH Thijssen and D Kurtz
Lilly Laboratory for Clinical Research, Eli Lilly and Company, Wishard Memorial Hospital, Indianapolis, IN 46219, USA.
OBJECTIVE: The pharmacokinetics and glucodynamics of a new insulin analog,
insulin lispro, and regular human insulin were compared and contrasted
after subcutaneous administrations in femoral, deltoid, and abdominal
injection sites. RESEARCH DESIGN AND METHODS: Single 0.2 U/kg doses of
insulin lispro and regular insulin were administered to 12 healthy subjects
in a six-way randomized crossover fashion. Each dose was given after an
overnight fast in one of three injection sites: abdominal, deltoid, or
femoral. Study drugs were given during a manual euglycemic glucose clamp.
Blood samples were collected over the 12-h clamp for measurement of
insulin-reactive components, with pharmacokinetic and glucodynamic
measurements derived from these serum insulin and clamp measurements.
RESULTS: Glucodynamic comparisons between insulin lispro and regular
insulin showed a greater maximum infusion rate (Rmax) at an earlier time
(TRmax), regardless of injection site. The total glucose infused (Gtot)
showed nearly identical values between sites for insulin lispro. Regular
insulin showed greater Gtot values from deltoid and femoral injections.
When comparisons were made between drugs, regular insulin produced
significantly greater Gtot, primarily driven by the increased Gtot from
deltoid and femoral injections. Greater maximum serum insulin
concentrations (Cmax) were experienced with insulin lispro at earlier times
(tmax), regardless of the injection site (P < 0.001). Abdominal
administrations produced the greatest Cmax values at the earliest tmax for
both regular insulin and insulin lispro. Deltoid and femoral injections had
lower Cmax values for both compounds. Shifts also occurred with tmax,
although these shifts were much greater with regular insulin than with
insulin lispro. Equivalent area under the curve (AUC) values were found
when compared between compounds. CONCLUSIONS: Slower absorption from
deltoid and femoral administrations resulted in an increased duration of
action for both regular insulin and insulin lispro when compared to
abdominal administration. However, notable increases in the onset of action
were only apparent with regular insulin. The consistency with insulin
lispro response from abdominal and extremity injection sites allows more
potential sites for subcutaneous injection with an assured rapid response.