GH and IGF-I combination therapy aimed to improve glucose sensitivity and body composition in GHD adults
Background
Growth Hormone Deficiency (GHD) in adults is associated with adverse metabolic profiles, including increased adiposity, impaired glucose tolerance (IGT), and a higher risk of type 2 diabetes. While GH replacement therapy can improve body composition, it sometimes exacerbates insulin resistance, particularly in patients with pre-existing glucose dysregulation. Insulin-like Growth Factor-I (IGF-I), a key mediator of GH action, also plays a crucial role in glucose metabolism. This study aimed to investigate whether a combined GH and IGF-I regimen could offer a more balanced approach, potentially mitigating GH's diabetogenic effects while leveraging its anabolic benefits to improve both body composition and glucose sensitivity in GHD patients with IGT or diabetes.
Study Design
This was a COMPLETED Phase 3, randomized, quadruple-blind clinical trial (NCT01020955) involving 14 adult patients diagnosed with Growth Hormone Deficiency (GHD) and either impaired glucose tolerance (IGT) or diabetes. Participants were randomized into two arms for a total duration of 6 months. The active comparator arm received NutropinAq (GH) at 0.15 mg/d for the first month, increasing to 0.3 mg/d for the subsequent 5 months, combined with Increlex (IGF-I) at 15 µg/kg/d for the first month, then 30 µg/kg/d for the remaining 5 months. The control arm received the identical NutropinAq (GH) regimen alongside a placebo for 6 months. The primary objective was to measure the effects of these treatments on glucose sensitivity and body composition.
Why It Matters
If successful, this combination therapy could offer a refined approach for GHD patients with glucose dysregulation. Current GH replacement protocols, while beneficial for body composition, can sometimes worsen insulin resistance, making treatment challenging for individuals already struggling with diabetes or IGT. A protocol combining GH and IGF-I might theoretically balance anabolic effects with improved glucose metabolism, potentially allowing GHD patients with metabolic comorbidities to safely benefit from GH therapy. This study's design aimed to explore whether such a synergistic or mitigating effect is achievable, paving the way for more tailored GHD treatment strategies that prioritize both body composition and metabolic health.
gh
igf-1
growth hormone deficiency
diabetes
impaired glucose tolerance
clinical trial