Reproducibility and Utility of OGTT in Acromegaly — ACROTEST  

Acromegaly Clinical Trial

Official title: Reproducibility and Utility of Growth Hormone Inhibition by Oral Glucose Tolerance Test for the Diagnosis of Acromegaly

Status Not yet recruiting

Clinical Trial Summary

Prospective study of reproducibility and utility of growth hormone inhibition by oral glucose tolerance test for the diagnosis of acromegaly, in acromegalic and non-acromegalic subjects, with a randomized double-blind crossover over placebo arm in the group of acromegalic patients

Clinical Trial Description

Rational: The initial step of biological diagnosis of acromegaly is based on assessment of IGF-I. According to current recommendations, the diagnosis must be confirmed by an oral glucose tolerance test (OGTT) to show that there is no growth hormone (GH) decrease lower than 1 μg/L (Katznelson , et al., 2014).

Reproducibility of GH suppression by the OGTT has never been evaluated in either acromegalic or healthy subjects, although it is essential to determine the reliability of this test. Spontaneous fluctuations in GH in acromegaly could significantly influence the response of GH to the OGTT and cause low reproducibility of the test in this population. In particular, this reliability could be different according to the typical or moderate clinical presentation because of the persistence of a residual ultradian rhythm of GH secretion.

The usefulness of oral glucose loading and the resulting hyperglycemia (which may limit GH secretion) has never been compared to an appropriate placebo (aspartame, at a dose equivalent to 75 g glucose), which does not cause hyperglycemia. Ingestion of 75 g of glucose is often responsible for nausea and vomiting. More rarely, the drop in blood glucose reactive to hyper insulinemia at the end of the test, can be the cause of discomfort.

Primary objective: To determine the reproducibility of the GH response to OGTT in acromegaly by studying, in subjects with acromegaly, changes in GH concentration within 2 hours after oral administration of 75 g of glucose at 2 repeated tests in the same subject.

Secondary objectives:

1. To analyze the reproducibility of the GH response to the OGTT as a function of the severity of acromegaly ("typical" form, "intermediate" form of acromegaly) and in a group of non-acromegalic subjects.

2. To evaluate the diagnostic value (utility) of OGTT in acromegaly by comparing, in subjects with acromegaly, the response of GH to oral administration of 75 g of glucose (OGTT) and 375 mg of aspartame (placebo).

3. Evaluate OGTT-stimulated insulin secretion in acromegalic and non-acromegalic subjects. ;

Related Conditions & MeSH terms

• Acromegaly

• NCT number: NCT04066569
• Study type: Interventional
• Source: Assistance Publique - Hôpitaux de Paris
• Contact: SALENAVE Sylvie, Dr
• Phone: 01 45 21 33 98
• Email: sylvie.salenave@aphp.fr
• Status: Not yet recruiting
• Phase: N/A
• Start date: September 10, 2019
• Completion date: December 10, 2022