Dataset Information

Dual GIP and GLP-1 Receptor Agonist Tirzepatide Improves Beta-cell Function and Insulin Sensitivity in Type 2 Diabetes.

ABSTRACT:

Context

Novel dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist (RA) tirzepatide demonstrated substantially greater glucose control and weight loss (WL) compared with selective GLP-1RA dulaglutide.

Objective

Explore mechanisms of glucose control by tirzepatide.

Design

Post hoc analyses of fasting biomarkers and multiple linear regression analysis.

Setting

Forty-seven sites in 4 countries.

Patients or other participants

Three hundred and sixteen subjects with type 2 diabetes.

Interventions

Tirzepatide (1, 5, 10, 15 mg), dulaglutide (1.5 mg), placebo.

Main outcome measures

Analyze biomarkers of beta-cell function and insulin resistance (IR) and evaluate WL contributions to IR improvements at 26 weeks.

Results

Homeostatic model assessment (HOMA) 2-B significantly increased with dulaglutide and tirzepatide 5, 10, and 15 mg compared with placebo (P ≤ .02). Proinsulin/insulin and proinsulin/C-peptide ratios significantly decreased with tirzepatide 10 and 15 mg compared with placebo and dulaglutide (P ≤ .007). Tirzepatide 10 and 15 mg significantly decreased fasting insulin (P ≤ .033) and tirzepatide 10 mg significantly decreased HOMA2-IR (P = .004) compared with placebo and dulaglutide. Markers of improved insulin sensitivity (IS) adiponectin, IGFBP-1, and IGFBP-2 significantly increased by 1 or more doses of tirzepatide (P < .05). To determine whether improvements in IR were directly attributable to WL, multiple linear regression analysis with potential confounding variables age, sex, metformin, triglycerides, and glycated hemoglobin A1c was conducted. WL significantly (P ≤ .028) explained only 13% and 21% of improvement in HOMA2-IR with tirzepatide 10 and 15 mg, respectively.

Conclusions

Tirzepatide improved markers of IS and beta-cell function to a greater extent than dulaglutide. IS effects of tirzepatide were only partly attributable to WL, suggesting dual receptor agonism confers distinct mechanisms of glycemic control.

SUBMITTER: Thomas MK

PROVIDER: S-EPMC7823251 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:Background and aimsThe pharmacokinetics (PK) and single-dose tolerability of tirzepatide, a dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist being developed for once-weekly treatment of type 2 diabetes (T2D), weight management, and nonalcoholic steatohepatitis, was evaluated in subjects with renal impairment versus healthy subjects with normal renal function.MethodsForty-five subjects, categorized by baseline renal status, i.e. mild (n = 8, estimated glomerular filtration rate [eGFR] 60-89 mL/min/1.73m2), moderate (n = 8, eGFR 30-59 mL/min/1.73m2), severe renal impairment (n = 7, eGFR < 30 mL/min/1.73m2), end-stage renal disease requiring dialysis (n = 8), and normal renal function (n = 14, eGFR ≥ 90 mL/min/1.73m2), received a single subcutaneous dose of tirzepatide 5 mg. Tirzepatide plasma concentrations up to 648 h postdose were measured to compute PK parameters. The primary analysis evaluated the ratios of area under the plasma concentration-time curves (AUCs) and maximum plasma drug concentration (Cmax) of renal impairment versus the normal renal function group (90% confidence interval [CI]). In addition, the relationship between PK parameters and continuous variables of renal function was assessed by linear regression.ResultsTirzepatide exposure was similar across renal impairment groups and healthy subjects. The 90% CI of ratios of AUCs and Cmax comparing each renal impairment group versus normal renal function spanned unity, except for a 25-29% increase in AUCs in the moderate renal impairment group. There was no significant relationship between tirzepatide exposure and eGFR. Few adverse events were reported across the renal impairment and normal renal function groups. The majority were mild in severity and of a gastrointestinal nature in the renal impairment groups.ConclusionThere were no clinically relevant effects of renal impairment on tirzepatide PK. Dose adjustment may not be required for patients with renal impairment.Clinical trial registrationClinicalTrials.gov NCT03482024.

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