EARLY EXPERIENCE WITH EXTENDED USE OF INSULIN-LIKE GROWTH-FACTOR-I INADVANCED CHRONIC-RENAL-FAILURE

Short-term high-dose insulin-like growth factor-1 (IGF-1) therapy has been shown to enhance glomerular filtration rate (GFR) in end-stage ch ronic renal failure (CRF), but the efficacy and safety of prolonged th erapy is unproven. To determine if prolonged therapy with IGF-1 can en hance renal function in advanced CRF, eight patients were entered into a study to receive one month of IGF-1 treatment, 60 mu g/kg subcutane ously b.i.d. Six patients completed the study and two dropped out for reasons considered to be unrelated to The IGF-I treatment. Baseline in ulin and PAH clearances averaged 17 +/- 3 and 66 +/- 14 ml/min/1.73 m( 2), respectively, in the subjects who completed the study. With treatm ent there was a modest 14% increase in the average GFR which approache d statistical significance (P = 0.051). After stopping treatment the c learance values returned to basal values. The PAH clearance showed a s imilar trend. There were no significant changes in BUN, serum creatini ne or electrolyte levels. On the other hand there were marked changes in the serum IGF binding protein (IGFBP) profile. Serum IGFBP-3 levels fell while IGFBP-1 and -2 levels rose during treatment, changes that likely affect the bioavailability of IGF-I. Thus, in this small series of patients IGF-I treatment produced significant changes in the serum IGFBP profile and a modest upward trend in the GFR.