Of the 53 AGHD subjects enrolled, 52 received AEZS-130, and 50 who had confirmed AGHD prior to study entry were included in this analysis, along with 48 controls. Two AGHD subjects could not be matched due to the combination of young age, high BMI and estrogen use. The objective of this clinical trial was to determine the efficacy and safety of AEZS-130 in the diagnosis of AGHD.
Mean peak growth hormone (GH) levels in AGHD patients and controls following AEZS-130 administration were 2.36ng/mL (range 0.03-33) and 17.71ng/mL (range 10.5-94), respectively. The receiver operating characteristic (ROC) plot analysis yielded an optimal GH cut-point of 2.7ng/mL, with 82% sensitivity, 92% specificity and a 13% misclassification rate. Obesity (BMI>30) was present in 58% of cases and controls, and peak GH levels were inversely associated with BMI in controls.
Adverse events (AE) were seen in 37% of AGHD patients and in 21% of controls following AEZS-130. In contrast, 61% of AGHD subjects and 30% of controls experienced AEs with L-ARG+GHRH. The most common AEs after AEZS-130 were unpleasant taste (19.2%) and diarrhea (3.8%) for the AGHD patients and unpleasant taste (4.2%) and diarrhea (4.2%) for the matched controls. AEs were generally mild or moderate in severity.
Of the 50 subjects studied with both stimulation tests, 70% expressed a preference for AEZS-130 over L-ARG+GHRH.
Summary and conclusions on the effect of BMI on optimal cut-off
Responses in normal subjects classified as obese, with BMI's above 30, were significantly lower than in leaner subjects. Since GH deficiency can lead to increased body fat, many of the patients also met criteria for obesity, and therefore, a lower peak GH cutoff is more accurate in separating obese normals from obese patients. Based upon these study results, a cut-off of 2.7 μg/L was optimal for subjects with a BMI ≥ 30 and a cutoff of 6.8 μg/L for subjects with a BMI of <30. Age had a much weaker effect on test performance and gender made no difference. Thus GH stimulation with oral AEZS-130 may provide a simple, rapid, safe, and well-tolerated diagnostic test for AGHD, with accuracy comparable to that of the GHRH-ARG test.