Glycaemic target attainment in people with Type 2 diabetes treated with insulin glargine/lixisenatide fixed-ratio combination: a post hoc analysis of the LixiLan-O and LixiLan-L trials

AIMS

Both fasting (FPG) and postprandial plasma glucose (PPG) contribute to HbA_1c levels. We investigated the relationship between achievement of American Diabetes Association (ADA) and American Association of Clinical Endocrinologists (AACE) recommended FPG and/or PPG targets and glycaemic efficacy outcomes in two trials.

METHODS

In this post hoc analysis, data from participants with Type 2 diabetes in the phase 3 LixiLan-O (NCT02058147) and LixiLan-L (NCT02058160) trials were evaluated to compare the relationship between achievement of society-recommended FPG and/or PPG targets and efficacy (HbA_1c change, HbA_1c goal attainment, weight change) and safety outcomes in the treatment groups.

RESULTS

Across treatment arms, iGlarLixi achieved the highest proportion of participants meeting both ADA- and AACE-recommended FPG and PPG targets at study end in both trials. A higher proportion of participants in the iGlarLixi (fixed-ratio combination of insulin glargine and lixisenatide) vs. insulin glargine alone or lixisenatide alone treatment arms achieved HbA_1c goals (P < 0.001 for overall comparisons), irrespective of ADA- or AACE-defined targets. Hypoglycaemia rates [any, documented symptomatic (plasma glucose ≤ 3.9 mmol/l), and clinically important (plasma glucose < 3.0 mmol/l)] were low across all groups. Participants treated with iGlarLixi tended to show weight loss or less weight gain compared with participants receiving insulin glargine alone. No differences were observed in average daily basal insulin dose at week 30 between the two treatment arms or across the different FPG and PPG target groups.

CONCLUSION

Insulin glargine and lixisenatide as a fixed-ratio combination resulted in more participants reaching both FPG and PPG targets, leading to better HbA_1c target attainment.

P1521In a 36-week placebo-controlled phase 2 trial in patients with non-alcoholic steatohepatitis (NASH), treatment with MGL-3196 (resmetirom) significantly reduces atherogenic lipoprotein particles

Background

MGL-3196 is a liver-directed, orally active, highly selective thyroid hormone receptor-β agonist being developed for the treatment of non-alcoholic steatohepatitis (NASH). In a 36-week Phase 2 NASH study, MGL-3196 treatment compared with placebo (PbO) resulted in significant reductions in hepatic fat, liver enzymes, NASH on liver biopsy, and atherogenic lipids including low-density lipoprotein cholesterol (LDL-C) and triglycerides. Most NASH patients die of cardiovascular disease (CVD), and, in NASH patients, CV risk correlates better with LDL particle than LDL-C levels.

Purpose

To determine the effects of MGL-3196 on lipoprotein particle concentrations in patients with NASH.

Methods

MGL-3196–05 (NCT02912260) is a 36-week multicenter, randomized, double-blind, placebo controlled study of NASH patients assessed with serial liver imaging and liver biopsies. Patients received 2:1 MGL-3196 80 mg (blinded ± 20 mg dose adjustment possible at Week 4 based on Week 2 pharmacokinetic data) or placebo once daily, for 36 weeks. Lipoprotein particle concentrations were assessed in fasting blood samples at baseline and Week (Wk) 36.

Results

As shown (Table), MGL-3196 significantly reduced the level of lipoprotein particles, with greater reductions in patients with baseline (BL) LDL-C ≥100 mg/dL and the patient group with higher MGL-3196 exposures (High exp).

Lipoprotein particles Particles (by NMR) (nmol/L) Time Point Placebo, n=34 MGL-3196 (all), n=73 MGL-3196 BL LDL-C ≥100 mg/dL, n=44; High Exp, n=25 (PbO BL ≥100 mg/dL, n=23 mean data not shown) Total LDL, mean (SD) BL 1234 (276) 1275 (328) 1443 (290) 1407 (267) Wk 36 1251 (323) 1045 (264) 1155 (248) 1090 (216) % change from BL vs PbO (SE), p value −19.6 (4.2), <0.0001 −19.8 (5.6), 0.0008 −22.8 (6.3), 0.0006 Small LDL, mean (SD) BL 746 (295) 835 (294) 887 (329) 916 (314) Wk 36 749 (343) 641 (207) 641 (234) 618 (149) % change from BL vs PbO (SE), p value −27.7 (8.9), 0.002 −34.3 (13.1), 0.01 −39.4 (14.7), 0.009 Total VLDL and Chylomicron, mean (SD) BL 56.8 (23.9) 55.9 (22.9) 61.4 (24.5) 66.0 (24.8) Wk 36 58.8 (24.4) 46.0 (21.1) 47.6 (22.9) 47.4 (23.1) % change from BL vs PbO (SE), p value −22.7 (6.9), 0.001 −27.2 (7.5), 0.0006 −34.7 (8.3), <0.0001 Large VLDL and Chylomicron, mean (SD) BL 6.3 (4.3) 8.7 (5.8) 8.9 (6.1) 10.2 (6.8) Wk 36 7.2 (4.5) 6.6 (3.9) 6.7 (4.1) 7.2 (4.7) % change from BL vs PBO (SE), p value −52.5 (11.8), <0.0001 −65.6 (15.5), <0.0001 −71.3 (17.4), 0.0001 BL, baseline; High exp, high MGL-3196 exposure based on % increase from baseline in sex hormone binding globulin, BL LDL-C ≥100, a prespecified group.

Conclusions

MGL-3196 significantly reduced atherogenic lipoprotein particles, particularly in NASH patients with greater BL hypercholesterolemia. These findings are consistent with a potentially beneficial effect of MGL-3196 on the CV risk profile in NASH patients.

Pramlintide in the treatment of diabetes

Diabetes treatment has traditionally focused on correcting insulin deficiency with exogenous insulin and oral agents designed to enhance insulin secretion or insulin sensitivity in peripheral tissues. The more recent view of diabetes as a disease that affects multiple hormones in addition to insulin has led to the development of new therapies more broadly aimed at restoring glucose homeostasis by correcting abnormalities in additional glucoregulatory hormones. Pramlintide, a synthetic analogue of the beta-cell hormone amylin, regulates the appearance of glucose in the circulation following meals through several mechanisms of action: slowing gastric emptying, preventing inappropriate postprandial secretion of glucagon and increasing satiety. Long-term studies have demonstrated that pramlintide improves postprandial glucose fluctuations and A1C while reducing insulin dose and body weight. This combination of benefits associated with pramlintide makes it an attractive new treatment option for patients with diabetes. Clinical Trial Registry Numbers: 137-155 open-label clinical trial: NCT00108004 (Pramlintide long-term, placebo-controlled clinical trials were completed prior to the requirement for NCT registry).

Decreased susceptibility to fatty acid-induced peripheral tissue insulin resistance in women

Elevation of plasma nonesterified fatty acid (NEFA) levels has been shown in various studies to induce peripheral tissue insulin resistance and impair the suppression of endogenous glucose production (EGP). These studies have been conducted predominantly in men. We compared the effects of elevated plasma NEFA levels on basal and insulin-stimulated glucose metabolism in 8 normal women (age 42 +/- 8 years [mean +/- SD], BMI 25 +/- 3 kg/m(2)) and 10 normal men (35 +/- 6 years, 24 +/- 3 kg/m(2)). Each subject underwent two 5-h 80 mU. m(-2). min(-1) hyperinsulinemic-euglycemic clamps with measurement of glucose kinetics (intravenous [3-(3)H]glucose) and substrate oxidation. Plasma NEFA levels were elevated in one study for 3 h before and during the clamp ( approximately 1 mmol/l in both groups) by infusion of 20% Intralipid (60 ml/h) and heparin (900 U/h). In the control studies, the men and women had similar insulin-stimulated glucose disposal rates (R(d)) and substrate oxidation rates. In the men, elevated NEFA levels decreased insulin-stimulated glucose R(d) during the final 40 min of the clamp by 23% (P < 0.001). By contrast, no significant change in glucose R(d) was found in the women (control 10.4 +/- 1.1, lipid study 9.9 +/- 1.3 mg. kg(-1). min(-1)). Glucose R(d) was also unchanged in six women studied at a lower insulin dose (40 mU. m(-2). min(-1)). During the last 40 min of the high-insulin dose clamps with elevated NEFA, glucose oxidation was decreased by 33% in the men (P < 0.001) and by 23% in the women (P < 0.02). Nonoxidative glucose R(d) at this time was decreased by 15% in the men (P = 0.02) but was not significantly affected in women. Basal EGP was unaffected by elevation of plasma NEFA levels in both groups. Suppression of EGP during the glucose clamps, however, was impaired. At the insulin infusion rate used, the magnitude of this defect was comparable in men and women. In summary, our findings suggest that although the effects on EGP appear comparable, the inhibitory effects of NEFA on peripheral tissue insulin sensitivity are observed in men but cannot be demonstrated in women.

Lack of effect of a physiological elevation of plasma non-esterified fatty acid levels on insulin secretion

Elevated plasma non-esterified fatty acid (NEFA) levels in obese subjects may contribute to their higher insulin secretory rates by direct effects on the islet B-cells. This may involve short-term metabolic effects, or long-term effects on islet B-cell mass, which is characteristically increased in obesity. We examined the effects of elevating plasma NEFA levels for 5.5 to 7 h on insulin secretion after an overnight fast and during a 90 min 12 mmol/l hyperglycemic clamp in 9 normal women (40.1 +/- 9.5 years [mean +/- SD]; BMI: 25.2 +/- 3.72 kg/m(2) ). Subjects were studied twice. In one study plasma NEFA levels were increased approximately 2-fold by infusion of 20% Intralipid (60 ml/h) and heparin (900 U/h) for 5.5 h before and throughout the glucose clamp. Elevated NEFA levels were associated with a small increase in fasting plasma glucose (5.0 +/- 0.1 vs 4.7 +/- 0.1 mmol/l, P <0.05) and C-peptide levels (0.54 +/- 0.09 vs 0.41 +/- 0.06 nmol/l, P <0.05). The increase in fasting insulin levels did not, however, reach statistical significance (9.0 +/- 2.5 vs 5.3 +/- 1.4 mU/l, NS). During the glucose clamp, plasma NEFA levels were suppressed to very low levels in the saline control study. Although plasma NEFA levels also fell in the lipid/heparin study, they remained significantly higher than on the control day, and somewhat higher than might be expected postprandially in obese subjects. During the glucose clamps, plasma glucose, insulin, and C-peptide profiles were similar on the two study days. No difference in either first or second phase insulin secretion was observed between the two studies. In conclusion, our findings do not support the idea that the exaggerated insulin secretion in obesity is mediated by short-term effects of plasma NEFA levels on islet B-cell metabolism, independent of plasma glucose levels.

Metabolic effects of troglitazone therapy in type 2 diabetic, obese, and lean normal subjects

OBJECTIVE

To characterize metabolic effects of troglitazone in type 2 diabetic, obese, and lean subjects, and examine the effects of troglitazone 2-3 weeks after discontinuation.

RESEARCH DESIGN AND METHODS

Nine type 2 diabetic, nine obese, and nine lean subjects underwent baseline metabolic studies including an 8-h meal-tolerance test (MTT) and a 5-h glucose clamp. Subjects then received troglitazone (600 mg/day) for 12 weeks and subsequently had repeat metabolic studies. Diabetic subjects remained off hypoglycemic agents for 2-3 weeks and then underwent a 5-h glucose clamp.

RESULTS

In diabetic subjects, fasting plasma glucose was reduced (P<0.05) and insulin-stimulated glucose disposal (Rd) was enhanced by treatment (P<0.02). The area under the MTT 8-h plasma glucose curve declined with therapy (P<0.001), and its change was positively correlated with the improvement in Rd (r = 0.75, P<0.05). There was also a positive correlation between the change in fasting hepatic glucose output (HGO) and the change in fasting plasma glucose with treatment (r = 0.92, P<0.001). Discontinuation of therapy for 2-3 weeks did not significantly affect fasting plasma glucose or insulin-stimulated glucose Rd. In obese subjects, insulin-stimulated glucose Rd improved with therapy (P<0.001), allowing for maintenance of euglycemia by lower plasma insulin concentrations (P<0.05). In lean subjects, an increase in fasting HGO (P<0.001) and glucose clearance (P<0.01) was observed.

CONCLUSIONS

Troglitazone lowers fasting and postprandial plasma glucose in type 2 diabetes by affecting both fasting HGO and peripheral insulin sensitivity. Its effects are evident 2-3 weeks after discontinuation. In obese subjects, its insulin sensitizing effects suggest a role for its use in the primary prevention of type 2 diabetes.