The effects of tirzepatide, a dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 receptor agonist, as an addition to insulin glargine for treatment of type 2 diabetes have not been described. OBJECTIVE To assess the efficacy and safety of tirzepatide added to insulin glargine in patients with type 2 diabetes with inadequate glycemic control.DESIGN, SETTING, AND PARTICIPANTS Randomized phase 3 clinical trial conducted at 45 medical research centers and hospitals in 8 countries (enrollment from August 30, 2019, to March 20, 2020 follow-up completed January 13, 2021) in 475 adults with type 2 diabetes and inadequate glycemic control while treated with once-daily insulin glargine with or without metformin.INTERVENTIONS Patients were randomized in a 1:1:1:1 ratio to receive once-weekly subcutaneous injections of 5-mg (n = 116), 10-mg (n = 119), or 15-mg (n = 120) tirzepatide or volume-matched placebo (n = 120) over 40 weeks. Tirzepatide was initiated at 2.5 mg/week and escalated by 2.5 mg every 4 weeks until the assigned dose was achieved. MAIN OUTCOMES AND MEASURESThe primary end point was mean change from baseline in glycated hemoglobin A 1c (HbA 1c ) at week 40. The 5 key secondary end points included mean change in body weight and percentage of patients achieving prespecified HbA 1c levels. RESULTS Among 475 randomized participants (211 [44%] women; mean [SD] age, 60.6 [9.9] years; mean [SD] HbA 1c , 8.31% [0.85%]), 451 (94.9%) completed the trial. Treatment was prematurely discontinued by 10% of participants in the 5-mg tirzepatide group, 12% in the 10-mg tirzepatide group, 18% in the 15-mg tirzepatide group, and 3% in the placebo group. At week 40, mean HbA 1c change from baseline was −2.40% with 10-mg tirzepatide and −2.34% with 15-mg tirzepatide vs −0.86% with placebo (10 mg: difference vs placebo, −1.53% [97.5% CI, −1.80% to −1.27%]; 15 mg: difference vs placebo, −1.47% [97.5% CI, −1.75% to −1.20%]; P < .001 for both). Mean HbA 1c change from baseline was −2.11% with 5-mg tirzepatide (difference vs placebo, −1.24% [95% CI, −1.48% to −1.01%]; P < .001]). Mean body weight change from baseline was −5.4 kg with 5-mg tirzepatide, −7.5 kg with 10-mg tirzepatide, −8.8 kg with 15-mg tirzepatide and 1.6 kg with placebo (5 mg: difference, −7.1 kg [95% CI, −8.7 to −5.4]; 10 mg: difference, −9.1 kg [95% CI, −10.7 to −7.5]; 15 mg: difference, −10.5 kg [95% CI, −12.1 to −8.8]; P < .001 for all). Higher percentages of patients treated with tirzepatide vs those treated with placebo had HbA 1c less than 7% (85%-90% vs 34%; P < .001 for all). The most common treatment-emergent adverse events in the tirzepatide groups vs placebo group were diarrhea (12%-21% vs 10%) and nausea (13%-18% vs 3%).CONCLUSIONS AND RELEVANCE Among patients with type 2 diabetes and inadequate glycemic control despite treatment with insulin glargine, the addition of subcutaneous tirzepatide, compared with placebo, to titrated insulin glargine resulted in statistically significant improvements in glycemic control after 40 weeks.

An increased intramyocellular lipid (IMCL) content, as quantified by 1 H-magnetic resonance spectroscopy ( 1 H-MRS), is associated with reduced insulin sensitivity. At present, it is unclear which factors determine IMCL formation and how rapidly IMCL accumulation can be induced. We therefore studied the impact of hyperinsulinemia and elevated circulating nonesterified fatty acid (NEFA) levels on IMCL formation and insulin sensitivity. We further evaluated the influence of a high-fat diet on IMCL storage. In the infusion protocol, 12 healthy male subjects underwent a 6-h hyperinsulinemic-euglycemic glucose clamp with concomitant infusion of Intralipid plus heparin. IMCL was quantified by 1 H-MRS in soleus (SOL) and tibialis anterior (TA) muscle at baseline and then every hour. IMCL levels started to increase significantly after 2 h, reaching a maximum of 120.8 ؎ 3.4% (SOL) and 164.2 ؎ 13.8% (TA) of baseline after 6 h (both P < 0.05). In parallel, the glucose infusion rate (GIR) decreased progressively, reaching a minimum of 60.4 ؎ 5.4% of baseline after 6 h. Over time, the GIR was strongly correlated with IMCL in TA (r ‫؍‬ ؊0.98, P < 0.003) and SOL muscle (r ‫؍‬ ؊0.97, P < 0.005). In the diet protocol, 12 male subjects ingested both a high-fat and low-fat diet for 3 days each. Before and after completion of each diet, IMCL levels and insulin sensitivity were assessed. After the high-fat diet, IMCL levels increased significantly in TA muscle (to 148.0 ؎ 16.9% of baseline; P ‫؍‬ 0.005), but not in SOL muscle (to 114.4 ؎ 8.2% of baseline; NS). Insulin sensitivity decreased to 83.3 ؎ 5.6% of baseline (P ‫؍‬ 0.033). There were no significant changes in insulin sensitivity or IMCL levels after the low-fat diet. The effects of the high-fat diet showed greater interindividual variation than those of the infusion protocol. The data from the lipid infusion protocol suggest a functional relationship between IMCL levels and insulin sensitivity. Similar effects could be induced by a high-fat diet, thereby underlining the physiological relevance of these observations.

The existence of metabolically relevant intramyocellular lipids (IMCL) as assessed by the noninvasive (1)H-magnetic resonance spectroscopy (MRS) has been established. In the present studies, we analyzed the relationships between IMCL in two muscle types [the predominantly nonoxidative tibialis muscle (tib) and the predominantly oxidative soleus muscle (sol)] and anthropometric data, aerobic capacity (VO(2)max, bicycle ergometry, n = 77) and insulin sensitivity (hyperinsulinemic euglycemic clamp, n = 105) using regression analysis. In univariate regression, IMCL (tib) was weakly but significantly correlated with percentage of body fat (r = 0.28, P = 0.01), whereas IMCL (sol) was better correlated with waist-to-hip ratio (r = 0.41, P < 0.0001). No significant univariate correlation with age or maximal aerobic power was observed. After adjusting for adiposity, IMCL (tib) was positively correlated with measures of aerobic fitness. A significant interaction term between VO(2)max and percentage of body fat on IMCL (tib) (P = 0.04) existed (whole model r(2) = 0.26, P = 0.001). In contrast, aerobic fitness did not influence IMCL (sol). No correlation between insulin sensitivity as such and IMCL (tib) (r = -0.13, P = 0.2) or IMCL (sol) (r = 0.03, P = 0.72) was observed. Nethertheless, a significant interaction term between VO(2)max and IMCL on insulin sensitivity existed [P = 0.04 (tib) and P = 0.02 (sol)]; [whole model (sol) r(2) = 0.61, P < 0.0001, (tib) r(2) = 0.60, P < 0.0001]. In conclusion, obesity and aerobic fitness are important determinants of IMCL. IMCL and insulin sensitivity are negatively correlated in untrained subjects. The correlation between the two parameters is modified by the extent of aerobic fitness and cannot be found in endurance trained subjects. Thus, measurements of aerobic fitness and body fat are indispensable for the interpretation of IMCL and its relationship with insulin sensitivity.

Aims To evaluate the efficacy and safety of ultra rapid lispro (URLi) versus lispro in adults with type 1 diabetes in a 26‐week, treat‐to‐target, phase 3 trial. Materials and methods After an 8‐week lead‐in to optimize basal insulin glargine or degludec, patients were randomized to double‐blind mealtime URLi (n = 451) or lispro (n = 442), or open‐label post‐meal URLi (n = 329). The primary endpoint was change from baseline glycated haemoglobin (HbA1c) to 26 weeks (non‐inferiority margin 0.4%), with multiplicity‐adjusted objectives for postprandial glucose (PPG) excursions after a meal test. Results Both mealtime and post‐meal URLi demonstrated non‐inferiority to lispro for HbA1c: estimated treatment difference (ETD) for mealtime URLi −0.08% [95% confidence interval (CI) −0.16, 0.00] and for post‐meal URLi +0.13% (95% CI 0.04, 0.22), with a significantly higher endpoint HbA1c for post‐meal URLi versus lispro (P = 0.003). Mealtime URLi was superior to lispro in reducing 1‐ and 2‐hour PPG excursions during the meal test: ETD −1.55 mmol/L (95% CI −1.96, −1.14) at 1 hour and − 1.73 mmol/L (95% CI −2.28, −1.18) at 2 hours (both P < 0.001). The rate and incidence of severe, documented and postprandial hypoglycaemia (<3.0 mmol/L) was similar between treatments, but mealtime URLi demonstrated a 37% lower rate in the period >4 hours after meals (P = 0.013). Injection site reactions were reported by 2.9% of patients on mealtime URLi, 2.4% on post‐meal URLi, and 0.2% on lispro. Overall, the incidence of treatment‐emergent adverse events was similar between treatments. Conclusions The results showed that URLi provided good glycaemic control, with non‐inferiority to lispro confirmed for both mealtime and post‐meal URLi, while superior PPG control was demonstrated with mealtime dosing.

Aims:To compare the efficacy and safety of LY2963016 insulin glargine (LY IGlar) and the reference product (Lantus®) insulin glargine (IGlar) in patients with type 1 diabetes (T1D). Methods