Diabetes Care, Vol 20, Issue 3 374-380, Copyright © 1997 by American Diabetes Association
Dual hormonal replacement with insulin and recombinant human insulin-like growth factor I in IDDM. Effects on glycemic control, IGF-I levels, and safety profile
T Quattrin, K Thrailkill, L Baker, J Litton, K Dwigun, M Rearson, M Poppenheimer, D Giltinan, N Gesundheit and P Martha
Department of Pediatrics, Children's Hospital of Buffalo, New York, USA. tquattri@chob.edu
OBJECTIVE: To examine if dual replacement with insulin and rhIGF-I,
recombinant human insulin-like growth factor I (rhIGF-I) may be safe and
result in improved metabolic control and reduced insulin usage. RESEARCH
DESIGN AND METHODS: Forty-three patients with IDDM were randomized to
receive a daily injection of rhIGF-I (80 mcg/kg s.c.) or placebo while on
conventional insulin therapy for 4 weeks. Insulin was adjusted in the
attempt to achieve predetermined goal glycemic values. Free and total
IGF-I, four daily blood glucoses, and HbA1c were measured. RESULTS: Before
randomization, placebo and rhIGF-I groups exhibited low plasma levels of
free and total IGF-I, which increased toward normal levels during the
treatment period only in the rhIGF group. The regression curve obtained
from the average of daily blood glucose measurements indicated that the
glycemic profile, overlapping in the lead-in period, exhibited a downward
trend in the rhIGF-I group during the treatment period. Mean blood glucose
level during the last 10 days of treatment was lower in the rhIGF-I groups
(174 +/- 37 vs. 194 +/- 32 mg/dl). HbA1c level was reduced by more than
one-half percent more in the rhIGF-I group (-1.85%) than in the control
group (-1.3%). The dose of regular insulin was significantly lower in the
rhIGF-I group (0.2 +/- 0.1 vs. 0.28 +/- 0.1 U. kg-1. 10 days-1 in the
placebo group; P < 0.05). CONCLUSIONS: rhIGF-I in combination with
conventional insulin treatment ameliorated the low plasma total and free
IGF-I levels and was well tolerated in IDDM. There was a trend toward
improved glycemic control, while the regular insulin dose was significantly
decreased.