Buccal spray insulin in subjects with impaired glucose tolerance: the prevoral study.
OBJECTIVE
Postprandial hyperglycaemia is a consequence of reduced first phase insulin response and is associated with increased cardiovascular risk and mortality. The aim of this proof-of-concept study was to investigate the safety and efficacy of treatment with buccal spray insulin (Oral-lyn™, Generex Biotechnology Corporation, Toronto, Ontario, Canada) on postprandial plasma glucose and insulin levels in subjects with impaired glucose tolerance (IGT).


METHODS
A total of 19 female and 12 male Caucasian subjects, 52.2 ± 13.5 (SD) years old, having a body mass index of 33.1 ± 6 (SD) kg/m² with confirmed IGT were included in the study. Subjects were randomized to take 4, 6 or 12 Oral-lyn puffs (1 puff = 1 s.c. rapid insulin UI) split into two equal doses each, one before and the second 30 min after a standard 75 g oral glucose tolerance test (OGTT). Glucose and insulin levels were measured at baseline and 30, 60, 90, 120 and 180 min afterwards.


RESULTS
Glucose fluctuations during OGTT were not modified by 4 or 6 Oral-lyn puffs. Treatment with 12 puffs was followed by 29.6% decrease in plasma glucose at 2 h and 26.8% decrease at 3 h, altogether p = 0.01. Considering all time points of the OGTT, there was a mean reduction of 15.8% in glucose levels. With 6 of the total 12 puffs used in group C there was a significant increase in the insulin levels during OGTT at 30 min (p < 0.04) but not at 2 or 3 h. No hypoglycaemic episodes were observed at any time points of the OGTT.


CONCLUSIONS
This proof-of-concept study demonstrates that treatment with buccal spray insulin is a simple and valuable therapy for reducing postprandial hyperglycaemia in obese subjects with IGT. Importantly, this treatment is safe and none of the study subjects experienced hypoglycaemia.
Department of Endocrinology and Diabetes, University Campus Bio-Medico, Rome, Italy.
A
A
Palermo
N
N
Napoli
S
S
Manfrini
A
A
Lauria
R
R
Strollo
P
P
Pozzilli
D000278:Administration, Buccal; D002170:Canada; D005260:Female; D018149:Glucose Intolerance / Q000188:drug therapy*; D006801:Humans; D006943:Hyperglycemia / Q000188:drug therapy* / Q000517:prevention & control; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D007328:Insulin / Q000008:administration & dosage* / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period / Q000187:drug effects*; D016896:Treatment Outcome
D007004:Hypoglycemic Agents; D007328:Insulin