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ObjectiveA novel dual GIP and GLP-1 receptor agonist, LY3298176, was developed to determine whether the metabolic action of GIP adds to the established clinical benefits of selective GLP-1 receptor agonists in type 2 diabetes mellitus (T2DM).MethodsLY3298176 is a fatty acid modified peptide with dual GIP and GLP-1 receptor agonist activity designed for once-weekly subcutaneous administration. LY3298176 was characterised in vitro, using signaling and functional assays in cell lines expressing recombinant or endogenous incretin receptors, and in vivo using body weight, food intake, insulin secretion and glycemic profiles in mice.A Phase 1, randomised, placebo-controlled, double-blind study was comprised of three parts: a single-ascending dose (SAD; doses 0.25–8 mg) and 4-week multiple-ascending dose (MAD; doses 0.5–10 mg) studies in healthy subjects (HS), followed by a 4-week multiple-dose Phase 1 b proof-of-concept (POC; doses 0.5–15 mg) in patients with T2DM (ClinicalTrials.gov no. NCT02759107). Doses higher than 5 mg were attained by titration, dulaglutide (DU) was used as a positive control. The primary objective was to investigate safety and tolerability of LY3298176.ResultsLY3298176 activated both GIP and GLP-1 receptor signaling in vitro and showed glucose-dependent insulin secretion and improved glucose tolerance by acting on both GIP and GLP-1 receptors in mice. With chronic administration to mice, LY3298176 potently decreased body weight and food intake; these effects were significantly greater than the effects of a GLP-1 receptor agonist.A total of 142 human subjects received at least 1 dose of LY3298176, dulaglutide, or placebo. The PK profile of LY3298176 was investigated over a wide dose range (0.25–15 mg) and supports once-weekly administration. In the Phase 1 b trial of diabetic subjects, LY3298176 doses of 10 mg and 15 mg significantly reduced fasting serum glucose compared to placebo (least square mean [LSM] difference [95% CI]: −49.12 mg/dL [−78.14, −20.12] and −43.15 mg/dL [−73.06, −13.21], respectively). Reductions in body weight were significantly greater with the LY3298176 1.5 mg, 4.5 mg and 10 mg doses versus placebo in MAD HS (LSM difference [95% CI]: −1.75 kg [−3.38, −0.12], −5.09 kg [−6.72, −3.46] and −4.61 kg [−6.21, −3.01], respectively) and doses of 10 mg and 15 mg had a relevant effect in T2DM patients (LSM difference [95% CI]: −2.62 kg [−3.79, −1.45] and −2.07 kg [−3.25, −0.88], respectively.The most frequent side effects reported with LY3298176 were gastrointestinal (vomiting, nausea, decreased appetite, diarrhoea, and abdominal distension) in both HS and patients with T2DM; all were dose-dependent and considered mild to moderate in severity.ConclusionsBased on these results, the pharmacology of LY3298176 translates from preclinical to clinical studies. LY3298176 has the potential to deliver clinically meaningful improvement in glycaemic control and body weight. The data warrant further clinical evaluation of LY3298176 for the treatment of T2DM and potentially obesity.

Aims/hypothesis Variation within six novel genetic loci has been reported to confer risk of type 2 diabetes and may be associated with beta cell dysfunction. We investigated whether these polymorphisms are also associated with impaired proinsulin to insulin conversion. Methods We genotyped 1,065 German participants for single nucleotide polymorphisms rs7903146 in TCF7L2, rs7754840 in CDKAL1, rs7923837 and rs1111875 in HHEX, rs13266634 in SLC30A8, rs10811661 in CDKN2A/B and rs4402960 in IGF2BP2. All participants underwent an OGTT. Insulin, proinsulin and C-peptide concentrations were measured at 0, 30, 60, 90 and 120 min during the OGTT. Insulin secretion was estimated from C-peptide or insulin levels during the OGTT using validated indices. We used the ratio proinsulin/insulin during the OGTT as indicator of proinsulin conversion. Results In our cohort, we confirmed the significant association of variants in TCF7L2, CDKAL1 and HHEX with reduced insulin secretion during the OGTT (p<0.05 for all). Variation in SLC30A8, CDKN2A/B and IGF2BP2 was not associated with insulin secretion. The risk alleles of the variants in TCF7L2, CDKAL1 and SLC30A8 reduced proinsulin to insulin conversion (p<0.05 for all), whereas the risk alleles in HHEX, CDKN2A/B and IGF2BP2 were not associated with reduced proinsulin to insulin conversion (p>0.6). Conclusions/interpretation Diabetes-associated variants in TCF7L2 and CDKAL1 impair insulin secretion and conversion of proinsulin to insulin. However, both aspects of beta cell function are not necessarily linked, as impaired insulin secretion is specifically present in variants of HHEX and impaired proinsulin conversion is specifically present in a variant of SLC30A8.

Aim: To assess the efficacy and tolerability of tirzepatide treatment using three different dose-escalation regimens in patients with type 2 diabetes. Materials and Methods:In this double-blind, placebo-controlled study, patients were randomized (1:1:1:1) to receive either once-weekly subcutaneous tirzepatide or placebo. The tirzepatide dose groups and dose-escalation regimens were: 12 mg (4 mg weeks 0-3; 8 mg weeks 4-7; 12 mg weeks 8-11), 15 mg-1 (2.5 mg weeks 0-1; 5 mg weeks 2-3; 10 mg weeks 4-7; 15 mg weeks 8-11) and 15 mg-2 (2.5 mg weeks 0-3; 7.5 mg weeks 4-7; 15 mg weeks 8-11). The primary objective was to compare tirzepatide with placebo in HbA1c change from baseline at 12 weeks.Results: Overall, 111 patients were randomized: placebo, 26; tirzepatide 12 mg, 29; tirzepatide 15 mg-1, 28; tirzepatide 15 mg-2, 28. The mean age was 57.4 years, HbA1c 8.4% and body mass index 31.9 kg/m 2 . At week 12, absolute HbA1c change from baseline (SE) was greater in the tirzepatide treatment groups compared with placebo (placebo, +0.2% [0.21]; 12 mg, −1.7% [0.19]; 15 mg-1, −2.0% [0.20]; 15 mg-2, −1.8% [0.19]). The incidence of nausea was: placebo, 7.7%; 12 mg group, 24.1%; 15 mg-1 group, 39.3%; 15 mg-2 group, 35.7%. Three patients discontinued the treatment because of adverse events, one from each of the placebo, 12 mg and 15 mg-1 groups.Conclusions: Tirzepatide treatment for 12 weeks resulted in clinically significant reductions in HbA1c. This suggests that lower starting doses and smaller dose increments are associated with a more favourable side effect profile.

To determine the effect of tirzepatide, a dual agonist of glucose-dependent insulinotropic polypeptide and glucagon-like peptide 1 receptors, on biomarkers of nonalcoholic steatohepatitis (NASH) and fibrosis in patients with type 2 diabetes mellitus (T2DM). RESEARCH DESIGN AND METHODSPatients with T2DM received either once weekly tirzepatide (1, 5, 10, or 15 mg), dulaglutide (1.5 mg), or placebo for 26 weeks. Changes from baseline in alanine aminotransferase (ALT), aspartate aminotransferase (AST), keratin-18 (K-18), procollagen III (Pro-C3), and adiponectin were analyzed in a modified intentionto-treat population. RESULTSSignificant (P < 0.05) reductions from baseline in ALT (all groups), AST (all groups except tirzepatide 10 mg), K-18 (tirzepatide 5, 10, 15 mg), and Pro-C3 (tirzepatide 15 mg) were observed at 26 weeks. Decreases with tirzepatide were significant compared with placebo for K-18 (10 mg) and Pro-C3 (15 mg) and with dulaglutide for ALT (10, 15 mg). Adiponectin significantly increased from baseline with tirzepatide compared with placebo (10, 15 mg). CONCLUSIONSIn post hoc analyses, higher tirzepatide doses significantly decreased NASH-related biomarkers and increased adiponectin in patients with T2DM.The prevalence of nonalcoholic fatty liver disease (NAFLD) is ;25% globally and ;60-75% in patients with type 2 diabetes mellitus (T2DM) (1,2). Nonalcoholic steatohepatitis (NASH) (NAFLD with inflammation and hepatocyte injury, with or without fibrosis) can progress to cirrhosis, liver failure, hepatocellular carcinoma, and increased cardiovascular risk (3,4). T2DM increases the risk of NASH twofold (5). Weight loss through lifestyle modification reduces liver fat; weight reductions $10% can induce NASH resolution in most patients (6).Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) promote weight loss and may have efficacy in NASH (7). Tirzepatide, a 39-amino acid synthetic peptide, has agonist activity at both glucose-dependent insulinotropic polypeptide (GIP) and GLP-1