Trial	Intervention and comparator	Design	Duration of intervention	Randomised (n)	Description of participants	Outcomes reported	Outcomes reported with interest of this review	Stated purpose of study
Almeda‐Valdes 2012	I: sitagliptin 100 mg/day, PO	Assume single centre, double blind (blinded to participants and investigators), parallel	2 weeks	13	Intermediate hyperglycaemia not defined, only described as clinical and biochemical diagnosis of prediabetic reactive hypoglycaemia. Mainly non‐obese women	Area under curve in early and late insulin secretion phase, symptoms of reactive hypoglycaemia	None	Quote: "The purpose of this study is to determine whether sitagliptin is effective in the treatment of reactive hypoglycemia by dysinsulinism."
	C: placebo, PO			15
Bock 2010	I: sitagliptin 100 mg/day, PO	Single centre, double blind (blinded to participants and investigators), parallel	8 weeks	11	Impaired fasting glucose, mainly obese women	Fasting and postprandial glucose, insulin and C‐peptide, glucagon‐like peptide, glucose‐dependent insulinotropic polypeptide, glucagon and endogenous glucose production. Glucose disappearance, systemic meal appearance, insulin action, insulin secretion	Postprandial glucose, fasting glucose	Quote: "The current experiments tested this hypothesis by measuring insulin secretion and action and fasting and postprandial glucose turnover before and after 8 weeks of therapy with a DPP‐4 inhibitor."
	C: placebo, PO			11
Kaku 2015	I1: sitagliptin 25 mg/day, PO	Multicentre, double blind (blinded to participants and investigators), parallel	8 weeks	82	Japanese people, IGT	Glucose, glucagon and insulin area under the curve 0‐2 hour during meal tolerance tests and oral glucose tolerance test, HbA1c, fasting glucose, 2‐hour glucose, adverse events, hypoglycaemia, DDP‐4 activity, reversion to normoglycaemia, electrocardiogram changes	HbA1c, fasting glucose, 2‐hour glucose, serious adverse events, adverse events, hypoglycaemia	Quote: "To evaluate the efficacy and tolerability of sitagliptin in subjects with impaired glucose tolerance (IGT)."
	I2: sitagliptin 50 mg/day, PO			77
	C: placebo, PO			83
Schwartz 2010	I: exenatide 10 μg/day, subcutaneous (administered prior to a high‐calorie, fat‐enriched breakfast meal)	Assumed single centre, double blind (blinded to participants and investigators), cross‐over	Participants studied twice within 1‐3 weeks. Only single injection exenatide and placebo	35	Mainly men, 20 participants had IGT and 15 had recent‐onset diet controlled T2DM. The authors provided separate data for the participants with IGT	Concentrations of triglycerides, apolipoproteins B‐48 and CIII, non‐esterified fatty acids, remnant lipoprotein cholesterol and triglycerides in serum or plasma, endothelial function, measured prior to the injection and 8 h postprandially	None	Quote: "In the present study, we tested the effects of a single acute injection of exenatide to determine what direct benefits (in the absence of changes in satiety, weight loss and other chronic effects) this agent may have on increments in triglycerides, apolipoproteins, and cholesterol‐and triglyceride‐rich remnant particles, following a standardized fat‐enriched meal challenge."
	C: placebo, subcutaneous (administered prior to a high‐calorie, fat‐enriched break fast meal)
C: control; DPP‐4: dipeptidyl‐peptidase‐4; HbA1c: glycosylated haemoglobin A1c; I: intervention; IGT: impaired glucose tolerance; n: number of participants; PO: per os (orally); T2DM: type 2 diabetes mellitus.