Different effects of basal insulin peglispro and insulin glargine on liver enzymes and liver fat content in patients with type 1 and type 2 diabetes

Liver insulinization as a driver of triglyceride dysmetabolism

Metabolic dysfunction-associated fatty liver disease (MAFLD) is an increasingly prevalent fellow traveller with the insulin resistance that underlies type 2 diabetes mellitus. However, the mechanistic connection between MAFLD and impaired insulin action remains unclear. In this Perspective, we review data from humans to elucidate insulin's aetiological role in MAFLD. We focus particularly on the relative preservation of insulin's stimulation of triglyceride (TG) biosynthesis despite its waning ability to curb hepatic glucose production (HGP). To explain this apparent 'selective insulin resistance', we propose that hepatocellular processes that lead to TG accumulation require less insulin signal transduction, or 'insulinization,' than do those that regulate HGP. As such, mounting hyperinsulinaemia that barely compensates for aberrant HGP in insulin-resistant states more than suffices to maintain hepatic TG biosynthesis. Thus, even modestly elevated or context-inappropriate insulin levels, when sustained day and night within a heavily pro-lipogenic metabolic milieu, may translate into substantial cumulative TG biosynthesis in the insulin-resistant state.

Preclinical exploration of combined glucagon inhibition and liver-preferential insulin for treatment of diabetes using in vitro assays and rat and mouse models

AIMS/HYPOTHESIS

Normalisation of blood glucose in individuals with diabetes is recommended to reduce development of diabetic complications. However, risk of severe hypoglycaemia with intensive insulin therapy is a major obstacle that prevents many individuals with diabetes from obtaining the recommended reduction in HbA_1c. Inhibition of glucagon receptor signalling and liver-preferential insulin action have been shown individually to have beneficial effects in preclinical models and individuals with diabetes (i.e. improved glycaemic control), but also have effects that are potential safety risks (i.e. alpha cell hyperplasia in response to glucagon receptor antagonists and increased levels of liver triacylglycerols and plasma alanine aminotransferase activity in response to glucagon receptor antagonists and liver-preferential insulin). We hypothesised that a combination of glucagon inhibition and liver-preferential insulin action in a dual-acting molecule would widen the therapeutic window. By correcting two pathogenic mechanisms (dysregulated glucagon signalling and non-physiological distribution of conventional insulin administered s.c.), we hypothesised that lower doses of each component would be required to obtain sufficient reduction of hyperglycaemia, and that the undesirable effects that have previously been observed for monotreatment with glucagon antagonists and liver-preferential insulin could be avoided.

METHODS

A dual-acting glucagon receptor inhibitor and liver-preferential insulin molecule was designed and tested in rodent models (normal rats, rats with streptozotocin-induced hyperglycaemia, db/db mice and mice with diet-induced obesity and streptozotocin-induced hyperglycaemia), allowing detailed characterisation of the pharmacokinetic and pharmacodynamic properties of the dual-acting molecule and relevant control compounds, as well as exploration of how the dual-acting molecule influenced glucagon-induced recovery and spontaneous recovery from acute hypoglycaemia.

RESULTS

This molecule normalised blood glucose in diabetic models, and was markedly less prone to induce hypoglycaemia than conventional insulin treatment (approximately 4.6-fold less potent under hypoglycaemic conditions than under normoglycaemic conditions). However, compared to treatment with conventional long-acting insulin, this dual-acting molecule also increased triacylglycerol levels in the liver (approximately 60%), plasma alanine aminotransferase levels (approximately twofold) and alpha cell mass (approximately twofold).

CONCLUSIONS/INTERPRETATION

While the dual-acting glucagon receptor inhibitor and liver-preferential insulin molecule showed markedly improved regulation of blood glucose, effects that are potential safety concerns persisted in the pharmacologically relevant dose range.

Prevalence and clinical determinants of non-alcoholic fatty liver disease by liver scores in adults with type 1 diabetes

AIMS

To investigate the prevalence and clinical risk factors for non-alcoholic fatty liver disease (NAFLD) in type 1 diabetes (T1DM) by liver scores.

METHODS

A retrospective, unicenter, cross-sectional analysis was performed of adults with T1DM from 2015 to 2018. Steatosis scores (hepatic steatosis index-HSI, Framingham steatosis index-FSI) and fibrosis scores (FIB-4 index, AST-to-platelet ratio index-APRI) were associated with clinical parameters.

RESULTS

We identified 447 patients, 38 ± 14.5 yrs, 54 % female, BMI 28 ± 5.9 kg/m². Liver steatosis was prevalent at 61 % by HSI ≥ 36 and 52 % by FSI ≥ 23. A majority of these individuals had normal liver transaminase levels. The presence of advanced fibrosis was 4 % by APRI > 0.7 and 4 % by FIB-4 > 2.67. BMI ≥ 25 kg/m² correlated with steatosis scores (P < 0.001) but not fibrosis scores. Older age (≥40 yrs), hypertension, dyslipidemia, and history of cardiovascular disease were associated with steatosis markers. Only 21 % had any abdominal imaging, 2 % had hepatology referral and 1 % had a liver biopsy. Glucagon-like peptide-1 agonist was prescribed in 5 % and thiazolidinedione in 4 %.

CONCLUSION

Liver scores indicating steatosis but not fibrosis is common in adults with T1DM with obesity and/or metabolic syndrome, and is associated with older age, hypertension, and dyslipidemia. NAFLD is under-diagnosed and under-investigated; a minority of patients have had any liver evaluation or treatment.

Approach to the Patient With Nonalcoholic Fatty Liver Disease

CONTEXT

Nonalcoholic fatty liver disease (NAFLD) is associated with obesity and type 2 diabetes (T2D), causing substantial burden from hepatic and extrahepatic complications. However, endocrinologists often follow people who are at the highest risk of its more severe form with nonalcoholic steatohepatitis or NASH (i.e., T2D or obesity with cardiometabolic risk factors). Endocrinologists are in a unique position to prevent cirrhosis in this population with early diagnosis and treatment.

OBJECTIVE

This work aims to offer endocrinologists a practical approach for the management of patients with NAFLD, including diagnosis, fibrosis risk stratification, and referral to hepatologists.

PATIENTS

(1) An asymptomatic patient with obesity and cardiometabolic risk factors, found to have hepatic steatosis; (2) a patient with T2D and NASH with clinically significant liver fibrosis; and (3) a liver transplant recipient with a history of NASH cirrhosis, with significant weight regain and with recurrent NAFLD on the transplanted organ.

CONCLUSION

NASH can be reversed with proper management of obesity and of T2D. While no agents are currently approved for the treatment of NASH, treatment should include lifestyle changes and a broader use of structured weight-loss programs, obesity pharmacotherapy, and bariatric surgery. Diabetes medications such as pioglitazone and some glucagon-like peptide 1 receptor agonists may also improve liver histology and cardiometabolic health. Sodium-glucose cotransporter-2 inhibitors and insulin may ameliorate steatosis, but their effect on steatohepatitis remains unclear. Awareness by endocrinologists about, establishing an early diagnosis of fibrosis (ie, FIB-4, liver elastography) in patients at high-risk of cirrhosis, long-term monitoring, and timely referral to the hepatologist are all critical to curve the looming epidemic of cirrhosis from NAFLD.

Effect of tirzepatide versus insulin degludec on liver fat content and abdominal adipose tissue in people with type 2 diabetes (SURPASS-3 MRI): a substudy of the randomised, open-label, parallel-group, phase 3 SURPASS-3 trial

BACKGROUND

Tirzepatide is a novel dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 receptor agonist under development for the treatment of type 2 diabetes. The aim of this substudy was to characterise the changes in liver fat content (LFC), volume of visceral adipose tissue (VAT), and abdominal subcutaneous adipose tissue (ASAT) in response to tirzepatide or insulin degludec in a subpopulation of the SURPASS-3 study.

METHODS

This substudy of the randomised, open-label, parallel-group, phase 3 SURPASS-3 trial was done at 45 medical research centres and hospitals across eight countries (Argentina, Austria, Greece, Hungary, Italy, Romania, Spain, and the USA). Eligible participants were adults with type 2 diabetes, a baseline HbA_1c 7·0-10·5% (53-91 mmol/mol), a BMI of at least 25 kg/m², stable weight, were insulin-naive, and on treatment with metformin alone or in combination with a SGLT2 inhibitor for at least 3 months before screening. In addition to the main study inclusion criteria, substudy participants had a fatty liver index of at least 60. Participants had an MRI scan and were randomised (1:1:1:1) in the main study to subcutaneous injection once per week of tirzepatide 5 mg, 10 mg, or 15 mg, or subcutaneous injection once per day of titrated insulin degludec, using an interactive web-response system, and were stratified by country, HbA_1c, and concomitant oral anti-hyperglycaemic medication. The primary efficacy endpoint was the change from baseline in LFC (as measured by MRI-proton density fat fraction [MRI-PDFF]) at week 52 using pooled data from the tirzepatide 10 mg and 15 mg groups versus insulin degludec. Analyses were assessed in the enrolled MRI population, which consisted of participants in the modified intention-to-treat population of the main study who also had a valid MRI at either baseline or after baseline. This is a substudy of the trial registered with ClinicalTrials.gov, number NCT03882970, and is complete.

FINDINGS

From April 1, 2019, to Nov 15, 2019, 502 participants were assessed for eligibility to participate in this substudy, 296 (59%) of whom were included in the enrolled MRI population and randomly assigned to treatment (tirzepatide 5 mg, n=71; tirzepatide 10 mg, n=79; tirzepatide 15 mg, n=72; and insulin degludec, n=74). Baseline demographics and clinical characteristics were similar across all treatment groups. From an overall mean baseline LFC of 15·71% (SD 8·93), the absolute reduction in LFC at week 52 was significantly greater for the pooled tirzepatide 10 mg and 15 mg groups (-8·09%, SE 0·57) versus the insulin degludec group (-3·38%, 0·83). The estimated treatment difference versus insulin degludec was -4·71% (95% CI -6·72 to -2·70; p<0·0001). The reduction in LFC was significantly correlated (p≤0·0006) with baseline LFC (ρ=-0·71), reductions in VAT (ρ=0·29), reductions in ASAT (ρ=0·33), and reductions in body weight (ρ=0·34) in the tirzepatide groups.

INTERPRETATION

Tirzepatide showed a significant reduction in LFC and VAT and ASAT volumes compared with insulin degludec in this subpopulation of patients with type 2 diabetes in the SURPASS-3 study. These data provide additional evidence on the metabolic effects of this novel dual GIP and GLP-1 receptor agonist.

FUNDING

Eli Lilly and Company.

American Association of Clinical Endocrinology Clinical Practice Guideline for the Diagnosis and Management of Nonalcoholic Fatty Liver Disease in Primary Care and Endocrinology Clinical Settings: Co-Sponsored by the American Association for the Study of Liver Diseases (AASLD)

OBJECTIVE

To provide evidence-based recommendations regarding the diagnosis and management of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) to endocrinologists, primary care clinicians, health care professionals, and other stakeholders.

METHODS

The American Association of Clinical Endocrinology conducted literature searches for relevant articles published from January 1, 2010, to November 15, 2021. A task force of medical experts developed evidence-based guideline recommendations based on a review of clinical evidence, expertise, and informal consensus, according to established American Association of Clinical Endocrinology protocol for guideline development.

RECOMMENDATION SUMMARY

This guideline includes 34 evidence-based clinical practice recommendations for the diagnosis and management of persons with NAFLD and/or NASH and contains 385 citations that inform the evidence base.

CONCLUSION

NAFLD is a major public health problem that will only worsen in the future, as it is closely linked to the epidemics of obesity and type 2 diabetes mellitus. Given this link, endocrinologists and primary care physicians are in an ideal position to identify persons at risk on to prevent the development of cirrhosis and comorbidities. While no U.S. Food and Drug Administration-approved medications to treat NAFLD are currently available, management can include lifestyle changes that promote an energy deficit leading to weight loss; consideration of weight loss medications, particularly glucagon-like peptide-1 receptor agonists; and bariatric surgery, for persons who have obesity, as well as some diabetes medications, such as pioglitazone and glucagon-like peptide-1 receptor agonists, for those with type 2 diabetes mellitus and NASH. Management should also promote cardiometabolic health and reduce the increased cardiovascular risk associated with this complex disease.

Functionally selective signaling and broad metabolic benefits by novel insulin receptor partial agonists

Insulin analogs have been developed to treat diabetes with focus primarily on improving the time action profile without affecting ligand-receptor interaction or functional selectivity. As a result, inherent liabilities (e.g. hypoglycemia) of injectable insulin continue to limit the true therapeutic potential of related agents. Insulin dimers were synthesized to investigate whether partial agonism of the insulin receptor (IR) tyrosine kinase is achievable, and to explore the potential for tissue-selective systemic insulin pharmacology. The insulin dimers induced distinct IR conformational changes compared to native monomeric insulin and substrate phosphorylation assays demonstrated partial agonism. Structurally distinct dimers with differences in conjugation sites and linkers were prepared to deliver desirable IR partial agonist (IRPA). Systemic infusions of a B29-B29 dimer in vivo revealed sharp differences compared to native insulin. Suppression of hepatic glucose production and lipolysis were like that attained with regular insulin, albeit with a distinctly shallower dose-response. In contrast, there was highly attenuated stimulation of glucose uptake into muscle. Mechanistic studies indicated that IRPAs exploit tissue differences in receptor density and have additional distinctions pertaining to drug clearance and distribution. The hepato-adipose selective action of IRPAs is a potentially safer approach for treatment of diabetes.

Liver-targeting drugs and their effect on blood glucose and hepatic lipids

The global epidemic of non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH) and the high prevalence among individuals with type 2 diabetes has attracted the attention of clinicians specialising in liver disorders. Many drugs are in the pipeline for the treatment of NAFLD/NASH, and several glucose-lowering drugs are now being tested specifically for the treatment of liver disease. Among these are nuclear hormone receptor agonists (e.g. peroxisome proliferator-activated receptor agonists, farnesoid X receptor agonists and liver X receptor agonists), fibroblast growth factor-19 and -21, single, dual or triple incretins, sodium-glucose cotransporter inhibitors, drugs that modulate lipid or other metabolic pathways (e.g. inhibitors of fatty acid synthase, diacylglycerol acyltransferase-1, acetyl-CoA carboxylase and 11β-hydroxysteroid dehydrogenase type-1) or drugs that target the mitochondrial pyruvate carrier. We have reviewed the metabolic effects of these drugs in relation to improvement of diabetic hyperglycaemia and fatty liver disease, as well as peripheral metabolism and insulin resistance.

Insulin treatment improves liver histopathology and decreases expression of inflammatory and fibrogenic genes in a hyperglycemic, dyslipidemic hamster model of NAFLD

Background

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are highly prevalent comorbidities in patients with Type 2 diabetes. While many of these patients eventually will need treatment with insulin, little is known about the effects of insulin treatment on histopathological parameters and hepatic gene expression in diabetic patients with co-existing NAFLD and NASH. To investigate this further, we evaluated the effects of insulin treatment in NASH diet-fed hamsters with streptozotocin (STZ) -induced hyperglycemia.

Methods

Forty male Syrian hamsters were randomized into four groups (n = 10/group) receiving either a NASH-inducing (high fat, fructose and cholesterol) or control diet (CTRL) for four weeks, after which they were treated with STZ or sham-injected and from week five treated with either vehicle (CTRL, NASH, NASH-STZ) or human insulin (NASH-STZ-HI) for four weeks by continuous s.c. infusion via osmotic minipumps.

Results

NASH-STZ hamsters displayed pronounced hyperglycemia, dyslipidemia and more severe liver pathology compared to both CTRL and NASH groups. Insulin treatment attenuated dyslipidemia in NASH-STZ-HI hamsters and liver pathology was considerably improved compared to the NASH-STZ group, with prevention/reversal of hepatic steatosis, hepatic inflammation and stellate cell activation. In addition, expression of inflammatory and fibrotic genes was decreased compared to the NASH-STZ group.

Conclusions

These results suggest that hyperglycemia is important for development of inflammation and profibrotic processes in the liver, and that insulin administration has beneficial effects on liver pathology and expression of genes related to inflammation and fibrosis in a hyperglycemic, dyslipidemic hamster model of NAFLD.

Improving the treatment of patients with diabetes using insulin analogues: current findings and future directions

Introduction: The aim of insulin replacement in insulin-deficient people (type 1 diabetes, pancreatic causes of diabetes, long-standing type 2 diabetes) is to approximate the physiologic insulin action profile as closely as possible. However, short-acting human insulins start too slow and act too long, causing postprandial hyperglycemia and delayed hypoglycemia, while the insulin action profile of long-acting human insulins is too variable in duration and strength of action, leading to insufficient basal insulin covering and peak insulin levels after injection causing early nocturnal hypoglycemia. Insulin analogues were designed to overcome these shortcomings. In insulin-resistant people (type 2 diabetes), insulin analogues contribute to more efficient and safer insulin supplementation. Areas covered: In this review, we describe the unmet needs for insulin therapy, the currently available short- and long-acting insulin analogues and some considerations on cardiovascular outcomes, use in special populations, and cost-effectiveness. Finally, we discuss what is new in the field of insulin analogues. Expert opinion: The development of insulin analogues is an important step in diabetes treatment. Despite many patients meeting their glycemic targets with the newest analogues, hypoglycemic episodes remain a major problem. More physiologic insulin regimens, with glucose-sensitive or organ-targeting insulin analogues may be the answer to these issues.

Efficacy of exenatide and insulin glargine on nonalcoholic fatty liver disease in patients with type 2 diabetes

BACKGROUND

The aim of this study was to investigate the efficacy of exenatide and insulin glargine in patients with newly diagnosed type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD).

METHODS

We performed a 24-week randomized controlled multicentre clinical trial. Seventy-six patients were randomly assigned 1:1 to receive exenatide or insulin glargine treatment. The endpoints included changes in liver fat content (LFC), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) measured by magnetic resonance spectroscopy, blood glucose, liver enzymes, lipid profile, body weight, and Fibrosis-4 index (FIB-4).

RESULTS

LFC, VAT, SAT, and FIB-4 were significantly reduced after exenatide treatment (ΔLFC, -17.55 ± 12.93%; ΔVAT, -43.57 ± 68.20 cm² ; ΔSAT, -28.44 ± 51.48 cm² ; ΔFIB-4, -0.10 ± 0.26; all P < .05). In comparison, only LFC (ΔLFC, -10.49 ± 11.38%; P < .05), and not VAT, SAT, or FIB-4 index (all P > .05), was reduced after insulin glargine treatment. Moreover, exenatide treatment resulted in greater reductions in alanine transaminase (ALT), aspartate transaminase (AST), and gamma glutamyl transpeptidase (GGT) than insulin glargine (P < 0.05). The body weight, waist circumference, postprandial plasma glucose, and low-density lipoprotein cholesterol (LDL-C) in the exenatide group also presented greater reductions than the insulin glargine group (P < .05). The proportion of adverse events were comparable between the two groups.

CONCLUSION

Both exenatide and insulin glargine reduced LFC in patients with drug-naive T2DM and NAFLD; however, exenatide showed greater reductions in body weight, visceral fat area, liver enzymes, FIB-4, postprandial plasma glucose, and LDL-C.

From NASH to diabetes and from diabetes to NASH: Mechanisms and treatment options

The worldwide prevalence of non-alcoholic fatty liver disease (NAFLD) is estimated to have reached 25% or more in adults. NAFLD is prevalent in obese individuals, but may also affect non-obese insulin-resistant individuals. NAFLD is associated with a 2- to 3-fold increased risk of developing type 2 diabetes (T2D), which may be higher in patients with more severe liver disease - fibrosis increases this risk. In NAFLD, not only the close association with obesity, but also the impairment of many metabolic pathways, including decreased hepatic insulin sensitivity and insulin secretion, increase the risk of developing T2D and related comorbidities. Conversely, patients with diabetes have a higher prevalence of steatohepatitis, liver fibrosis and end-stage liver disease. Genetics and mechanisms involving dysfunctional adipose tissue, lipotoxicity and glucotoxicity appear to play a role. In this review, we discuss the altered pathophysiological mechanisms that underlie the development of T2D in NAFLD and vice versa. Although there is no approved therapy for the treatment of NASH, we discuss pharmacological agents currently available to treat T2D that could potentially be useful for the management of NASH.

Plasma Fibroblast Growth Factor 21 Is Associated With Severity of Nonalcoholic Steatohepatitis in Patients With Obesity and Type 2 Diabetes

CONTEXT

The relationship between plasma fibroblast growth factor 21 (FGF21), insulin resistance, and steatohepatitis has not been systematically assessed.

OBJECTIVE

To determine if higher plasma FGF21 is associated with worse steatohepatitis on liver biopsy in patients with nonalcoholic fatty liver disease (NAFLD).

DESIGN AND SETTING

Cross-sectional study in a university hospital.

PATIENTS INTERVENTIONS AND MAIN OUTCOME MEASURES

Patients with a body mass index >25 (n = 187) underwent: (i) euglycemic hyperinsulinemic clamp to assess tissue-specific insulin resistance (IR); (ii) liver magnetic resonance spectroscopy for intrahepatic triglyceride quantification, (iii) liver biopsy (if NAFLD present; n = 146); and (iv) fasting plasma FGF21 levels.

METHODS AND RESULTS

Patients were divided into three groups: (i) No NAFLD (n = 41); (ii) No nonalcoholic steatohepatitis (NASH) (patients with isolated steatosis or borderline NASH; n = 52); and (iii) NASH (patients with definite NASH; n = 94). Groups were well-matched for age/sex, prevalence of type 2 diabetes mellitus, and hemoglobin A1c. During euglycemic hyperinsulinemic insulin clamp, insulin sensitivity in skeletal muscle and adipose tissue worsened from No NAFLD to NASH (both P < 0.001). Plasma FGF21 levels correlated inversely with insulin sensitivity in adipose tissue (r = -0.17, P = 0.006) and skeletal muscle (r = -0.23, P = 0.007), but not with liver insulin sensitivity. Plasma FGF21 was higher in patients with NASH (453 ± 262 pg/mL) when compared with the No NASH (341 ± 198 pg/mL, P = 0.03) or No NAFLD (325 ± 289 pg/mL, P = 0.02) groups. Plasma FGF21 increased with the severity of necroinflammation (P = 0.02), and most significantly with worse fibrosis (P < 0.001), but not with worsening steatosis (P = 0.60).

CONCLUSIONS

Plasma FGF21 correlates with severity of steatohepatitis, in particular of fibrosis, in patients with NASH. Measurement of FGF21 may help identify patients at the highest risk of disease progression.

Effect of canagliflozin treatment on hepatic triglyceride content and glucose metabolism in patients with type 2 diabetes

AIM

To evaluate the impact of the sodium glucose co-transporter 2 inhibitor canagliflozin on intrahepatic triglyceride (IHTG) accumulation and its relationship to changes in body weight and glucose metabolism.

MATERIALS AND METHODS

In this double-blind, parallel-group, placebo-controlled, 24-week trial subjects with inadequately controlled type 2 diabetes mellitus (T2DM; HbA1c = 7.7% ± 0.7%) from two centres were randomly assigned (1:1) to canagliflozin 300 mg or placebo. We measured IHTG by proton-magnetic resonance spectroscopy (primary outcome), hepatic/muscle/adipose tissue insulin sensitivity during a 2-step euglycaemic insulin clamp, and beta-cell function during a mixed meal tolerance test. Analyses were per protocol.

RESULTS

Between 8 September 2014-13 June 2016, 56 patients were enrolled. Canagliflozin reduced HbA1c (placebo-subtracted change: -0.71% [-1.08; -0.33]) and body weight (-3.4% [-5.4; -1.4]; both P ≤ 0.001). A numerically larger absolute decrease in IHTG occurred with canagliflozin (-4.6% [-6.4; -2.7]) versus placebo (-2.4% [-4.2; -0.6]; P = 0.09). In patients with non-alcoholic fatty liver disease (n = 37), the decrease in IHTG was -6.9% (-9.5; -4.2) versus -3.8% (-6.3; -1.3; P = 0.05), and strongly correlated with the magnitude of weight loss (r = 0.69, P < 0.001). Body weight loss ≥5% with a ≥30% relative reduction in IHTG occurred more often with canagliflozin (38% vs. 7%, P = 0.009). Hepatic insulin sensitivity improved with canagliflozin (P < 0.01), but not muscle or adipose tissue insulin sensitivity. Beta-cell glucose sensitivity, insulin clearance, and disposition index improved more with canagliflozin (P < 0.05).

CONCLUSIONS

Canagliflozin improves hepatic insulin sensitivity and insulin secretion and clearance in patients with T2DM. IHTG decreases in proportion to the magnitude of body weight loss, which tended to be greater and occur more often with canagliflozin.

Effects of hepato-preferential basal insulin peglispro on nuclear magnetic resonance biomarkers lipoprotein insulin resistance index and GlycA in patients with diabetes

AIM

To characterize the effects of hepato-preferential basal insulin peglispro (BIL) and insulin glargine on insulin resistance (lipoprotein insulin resistance index [LP-IR]) and inflammation (GlycA), and to explore the biological implications.

METHODS

This substudy included 847 patients with Type 1 diabetes (T1D) or Type 2 diabetes (T2D) in four cohorts of the BIL development program. LP-IR and GlycA were measured before and after insulin treatment. Correlations between LP-IR, GlycA, clinical parameters and liver biomarkers were assessed.

RESULTS

LP-IR and GlycA were higher in T2D than T1D. LP-IR increased in patients switched from basal insulins to BIL but not in insulin-naive patients. GlycA decreased in T2D patients treated with BIL and T1D patients treated with glargine.

CONCLUSION

These exploratory analyses help to characterize differences in biological effects between BIL and glargine treatment.

Open-label, randomized study comparing basal insulin peglispro and insulin glargine, in combination with oral antihyperglycemic medications, in insulin-naïve Asian patients with type 2 diabetes

INTRODUCTION

The present phase 3, randomized, open-label study compared the efficacy and safety of basal insulin peglispro with insulin glargine after 26 weeks of treatment when added to oral antihyperglycemic medications in insulin-naïve Asian patients with type 2 diabetes.

MATERIALS AND METHODS

The primary objective was to show non-inferiority of the change in glycated hemoglobin from baseline to 26 weeks.

RESULTS

At 26 weeks, insulin peglispro was non-inferior to glargine, meeting the primary objective. Patients receiving insulin peglispro (n = 192) showed a greater reduction in glycated hemoglobin from baseline compared with glargine (n = 196); -1.6 vs -1.4%, P = 0.005) and in fasting serum glucose (-61.2 vs -54.8 mg/dL, P = 0.02). A significantly higher proportion of patients receiving insulin peglispro achieved glycated hemoglobin <7% (57 vs 44%, P = 0.012). Insulin peglispro patients showed significantly less weight gain from baseline (1.1 vs 1.6 kg, P = 0.03). Relative rates (insulin peglispro/glargine) of total and nocturnal hypoglycemia through 26 weeks were 1.06 (P = 0.67) and 0.7 (P = 0.10), respectively. Significantly more insulin peglispro-treated patients experienced adverse events compared with glargine-treated patients (P = 0.042). Alanine aminotransferase and aspartate aminotransferase were significantly increased from baseline with insulin peglispro compared with glargine at week 26 (3.5 vs -4.6 IU/L and 2.8 vs -1.5 IU/L, respectively; P < 0.001). The incidence of injection site reactions was low and did not differ between the treatments.

DISCUSSION

Insulin peglispro provided better glycemic control vs glargine with no differences in hypoglycemia and increased aminotransferases in insulin-naïve Asian patients with type 2 diabetes.

Cytokeratin-18 and enhanced liver fibrosis scores in type 1 and type 2 diabetes and effects of two different insulins

Data on cytokeratin-18 (K-18) and enhanced liver fibrosis (ELF) score in insulin-treated diabetes patients with non-alcoholic fatty liver disease (NAFLD) are limited. This study analyzed phase III data comparing basal insulin peglispro (BIL) and insulin glargine in type 1 (T1D), and type 2 diabetes (T2D) (insulin-naïve and insulin-treated). Alanine aminotransferase (ALT), K-18, ELF scores and liver fat content (LFC), measured by MRI, were obtained longitudinally. Baseline K-18 (U/L) was higher in T2D (range: 207‒247) than T1D (range: 148‒183), correlated with ALT in all populations (r (range) 0.264‒0.637, p<0.05), but with LFC only in T2D (r (range) 0.474‒0.586, p<0.05). K-18 increased significantly from baseline in BIL-treated, but not glargine-treated patients. Change from baseline (CFB) K-18 was significantly correlated with CFB in ALT in BIL-treated T2D populations. Baseline ELF scores were higher in T2D (range: 9.12‒9.20) than T1D (range: 8.24‒8.36), correlated with ALT in T1D only (0.209, p<0.05), and not correlated with LFC in any population. ELF scores increased significantly from baseline in BIL-treated but not glargine-treated patients. There were no correlations between CFB in LFC and ELF score at week 52 in any treatment group/population. In all BIL-treated populations, CFB in ALT and CFB in ELF score at week 52 were positively correlated. These data characterize associations of K-18 and ELF score with ALT and LFC in insulin-treated patients with T1D and T2D. Hepatopreferential insulins may be associated with increased K-18 and ELF scores but mechanisms and clinical significance are unknown. ClinicalTrials.gov identifiers are NCT01481779, NCT01435616, NCT01454284 and NCT01582451.

Non-alcoholic fatty liver disease (NAFLD) prevalence and its metabolic associations in patients with type 1 diabetes and type 2 diabetes

We investigated non-alcoholic fatty liver disease (NAFLD) prevalence and its metabolic associations in patients with type 1 diabetes (T1D), and in insulin-naïve and insulin-treated patients with type 2 diabetes (T2D). Baseline data from patients who had liver fat content (LFC) evaluated by magnetic resonance imaging in four phase 3 studies of basal insulin peglispro (BIL) were analysed. Associations of NAFLD with clinical characteristics, glycaemic control and diabetes therapy were evaluated. The prevalence of NAFLD (defined as LFC ≥ 6%) was low in T1D (8.8%) but high in T2D, with greater prevalence in insulin-naïve (75.6%) vs insulin-treated (61.7%) T2D patients. LFC (mean ± SD) was higher in T2D patients (insulin-naïve, 13.0% ± 8.4%; insulin-treated, 10.2% ± 7.8%) than in T1D patients (3.2% ± 3.2%). In T2D, NAFLD was associated with several markers of insulin resistance. In all three populations, there was an absence of association of HbA1c with LFC, but insulin doses were higher in patients with NAFLD.

Insulin analogues in type 1 diabetes mellitus: getting better all the time

The treatment of type 1 diabetes mellitus consists of external replacement of the functions of β cells in an attempt to achieve blood levels of glucose as close to the normal range as possible. This approach means that glucose sensing needs to be replaced and levels of insulin need to mimic physiological insulin-action profiles, including basal coverage and changes around meals. Training and educating patients are crucial for the achievement of good glycaemic control, but having insulin preparations with action profiles that provide stable basal insulin coverage and appropriate mealtime insulin peaks helps people with type 1 diabetes mellitus to live active lives without sacrificing tight glycaemic control. Insulin analogues enable patients to achieve this goal, as some have fast action profiles, and some have very slow action profiles, which gives people with type 1 diabetes mellitus the tools to achieve dynamic insulin-action profiles that enable tight glycaemic control with a risk of hypoglycaemia that is lower than that with human short-acting and long-acting insulins. This Review discusses the established and novel insulin analogues that are used to treat patients with type 1 diabetes mellitus and provides insights into the future development of insulin analogues.

The effects of basal insulin peglispro vs. insulin glargine on lipoprotein particles by NMR and liver fat content by MRI in patients with diabetes

Background

In Phase 2/3 studies of basal insulin peglispro (BIL) compared to insulin glargine, patients with type 1 or type 2 diabetes previously treated with insulin and randomized to BIL had an increase in serum triglycerides (TGs). To further understand lipoprotein changes, a lipid substudy which included liver fat content was designed to assess relationships among the measured variables for each diabetes cohort and compare the hepato-preferential insulin BIL to glargine.

Methods

In three cohorts of patients with diabetes (type 1, type 2 insulin naïve, and type 2 previously on insulin; n = 652), liver fat content (LFC) was determined by magnetic resonance imaging (MRI) and blood lipids were analyzed by nuclear magnetic resonance (NMR) spectroscopy at baseline, 26 and 52 weeks of treatment. Apolipoproteins, adiponectin, and other lipid parameters were also measured. Descriptive statistics were done, as well as correlation analyses to look for relationships among LFC and lipoproteins or other lipid measures.

Results

In patients with type 1 diabetes treated with BIL, but not glargine, small LDL and medium and large VLDL subclass concentrations increased from baseline. In patients with type 2 diabetes previously on insulin and treated with BIL, large VLDL concentration increased from baseline. In insulin naïve patients with type 2 diabetes treated with BIL, there were very few changes, while in those treated with glargine, small LDL and large VLDL decreased from baseline. Baseline LFC correlated significantly in one or more cohorts with baseline large VLDL, small LDL, VLDL size, and Apo C3. Changes in LFC by treatment showed generally weak correlations with lipoprotein changes, except for positive correlations with large VLDL and VLDL size. Adiponectin was higher in patients with type 1 diabetes compared to patients with type 2 diabetes, but decreased with treatment with both BIL and glargine.

Conclusions

The lipoprotein changes were in line with the observed changes in serum TGs; i.e., the cohorts experiencing increased TGs and LFC with BIL treatment had decreased LDL size and increased VLDL size. These data and analyses add to the currently available information on the metabolic effects of insulins in a very carefully characterized cohort of patients with diabetes.

Clinicaltrials.gov registration numbers and dates NCT01481779 (2011), NCT01435616 (2011), NCT01454284 (2011), NCT01582451 (2012)

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0555-1) contains supplementary material, which is available to authorized users.

Chronic Toxicology Studies of Basal Insulin Peglispro in Rats and Dogs: A Novel, PEGylated Insulin Lispro Analog with a Prolonged Duration of Action

Basal insulin peglispro (BIL) consists of insulin lispro with a 20-kDa polyethylene glycol (PEG) moiety covalently attached to lysine B28. Because chronic parenteral administration of PEGylated proteins to animals has sometimes resulted in PEG vacuolation of tissue macrophages, renal tubular cells, and choroid plexus ependymal cells, we investigated whether chronic subcutaneous (sc) injection of BIL in rats (52 weeks) and dogs (39 weeks) was associated with systemic toxicities or other changes, including vacuolation of tissue macrophages, renal tubular cells, and ependymal cells. Rats and dogs received daily sc injections of BIL (rats: 0.17, 0.45, or 1.15 mg/kg/d and dogs: 0.025, 0.10, or 0.20 mg/kg/d) and the reference compound, HUMULIN N® (neutral protamine Hagedorn [NPH] human insulin; rats: 0.15 mg/kg/d and dogs: 0.02–0.03 mg/kg/d). Animals were evaluated for standard end points including mortality, clinical signs, body weights, toxicokinetics, glucodynamics, clinical pathology, and morphological pathology. Nonadverse injection site lipohypertrophy occurred for all BIL and NPH doses but more frequently with BIL. No BIL-related hyperplasia or neoplasia was observed. There was no vacuolation of tissue macrophages, renal tubular cells, or ependymal cells attributable to PEG. These studies demonstrate BIL is not associated with tissue vacuolation attributable to PEG at 4- to 6-fold multiple of the median clinical exposure in patients with diabetes.

How Can a Good Idea Fail? Basal Insulin Peglispro [LY2605541] for the Treatment of Type 2 Diabetes

INTRODUCTION

Lack of control in diabetic patients has stimulated the development of new insulin analogues. One of these was basal insulin peglispro (BIL) or LY2605541; it had a large hydrodynamic size, flat pharmacokinetic profile, half life of 2-3 days and acted preferably in the liver.

METHODS

We reviewed the recent literature examining the pharmacokinetics, pharmacodynamics, efficacy and safety of BIL treatment in type 2 diabetes patients.

RESULTS

The pharmacodynamic and pharmacokinetic outline of BIL seemed to have an advantage over neutral protamine Hagedorn and glargine insulins. Recently, phase 3 studies suggested BIL was superior to glargine in reducing glucose levels in type 1 and type 2 diabetes patients in addition to causing less weight gain. It showed a different hypoglycaemia rate profile depending on the study population, with less nocturnal hypoglycaemia compared to glargine. Unfortunately, it caused higher transaminase and triglyceride levels, which led the company to discontinue development. The decision came after it had been analysed by the regulatory authorities and other external experts concerning the worse liver profile data from the IMAGINE trials.

CONCLUSIONS

BIL was an adequate basal insulin analogue with interesting specific properties. Unfortunately the disadvantages as shown in the lipid values and liver function tests led to its failure.

A randomized clinical trial of basal insulin peglispro vs NPH in insulin-naïve patients with type 2 diabetes: the IMAGINE 6 trial

AIMS

Basal insulin peglispro (BIL) has a longer duration of action than conventional insulin analogues and a hepato-preferential mechanism of action. This study assessed whether BIL was non-inferior to isophane insulin (NPH) in reducing HbA1c in insulin-naïve patients with type 2 diabetes, when added to pre-study oral anti-hyperglycaemic medications.

MATERIALS AND METHODS

This was a Phase 3, open-label, treat-to-target (TTT), randomized trial with a 2-week lead-in, 26-week treatment and a 4-week safety follow-up period. Patients were randomized to bedtime (pm) NPH, morning (am) BIL or pm BIL in a 1:1:1 ratio.

RESULTS

Six hundred and forty-one patients [NPH, n = 213; BIL, n = 428 (am, n = 213; pm, n = 215)] received study drug. BIL was non-inferior to NPH for HbA1c change from baseline at Week 26 with a between-treatment difference (95% confidence interval) of -0.37% (-0.50, -0.23%). HbA1c at baseline was 8.5%, and was lower in BIL- vs NPH-treated patients after 26 weeks of treatment (6.8% vs 7.1%; P < .001). More BIL-treated patients achieved HbA1c <7.0% and HbA1c <7.0% without nocturnal hypoglycaemia. Fasting serum glucose levels and nocturnal hypoglycaemia rates were lower in BIL-treated patients; total hypoglycaemia rates were similar. Treatment-emergent adverse events were similar between groups. Fasting triglycerides decreased from baseline in both groups and to a greater extent with NPH, but were not significantly different between groups at Week 26. Mean alanine aminotransferase (ALT) increased with BIL treatment, but there was no evidence of acute severe hepatotoxicity.

CONCLUSIONS

In this TTT study, BIL treatment showed clinically relevant improvements in glycaemic control and a significant reduction in nocturnal hypoglycaemia compared to NPH.

Basal insulin peglispro: Overview of a novel long-acting insulin with reduced peripheral effect resulting in a hepato-preferential action

Basal insulin peglispro (BIL) is a novel basal insulin with a flat, prolonged activity profile. BIL has been demonstrated in a dog model, in healthy men and in patients with type 1 diabetes (T1D) to have significant hepato-preferential action resulting from reduced peripheral activity. In the IMAGINE-Phase 3 clinical trial program, more than 6000 patients were included, of whom ~3900 received BIL. Of the 7 pivotal IMAGINE trials, 3 studies were double-blinded and 3 were in T1D patients. BIL consistently demonstrated a greater HbA1c reduction, less glycaemic variability and a clinically relevant reduction in the rates of nocturnal hypoglycaemia across comparator [glargine and isophane insulin (NPH)] studies. Trials using basal/bolus regimens had higher rates of total hypoglycaemia with BIL due to higher rates of daytime hypoglycaemia. Severe hypoglycaemia rates were similar to comparator among both patients with T1D or type 2 diabetes (T2D). T1D patients lost weight compared with glargine (GL). Patients with T2D tended to gain less weight with BIL than with glargine. Compared to glargine, BIL was associated with higher liver fat, triglycerides and alanine aminotransferase (ALT) levels, including a higher frequency of elevation of ALT ≥3 times the upper limit of normal, but without severe, acute drug-induced liver injury. Injection site reactions, primarily lipohypertrophy, were more frequent with BIL. In conclusion, BIL demonstrated better glycaemic control with reduced glucose variability and nocturnal hypoglycaemia but higher triglycerides, ALT and liver fat relative to conventional comparator insulin. The hepato-preferential action of BIL with reduced peripheral activity may account for these findings.

A randomized clinical trial comparing basal insulin peglispro and insulin glargine, in combination with prandial insulin lispro, in patients with type 1 diabetes: IMAGINE 1

AIMS

The primary objective was to demonstrate that basal insulin peglispro (BIL) was non-inferior compared with insulin glargine (GL) for haemoglobin A1c (HbA1c) at 26 weeks with a non-inferiority margin of 0.4%.

MATERIALS AND METHODS

IMAGINE 1 was a Phase 3, open-label, parallel-arm study conducted in nine countries. Adults with type 1 diabetes (n = 455) were randomized (2:1) to bedtime BIL or GL in combination with prandial insulin lispro for 78 weeks, with a primary endpoint of 26 weeks. An electronic diary facilitated data capture and insulin dosing calculations for intensive insulin management.

RESULTS

At 26 weeks, mean HbA1c was 7.06% ± 0.04% and 7.43% ± 0.06% for patients assigned to BIL (N = 295) and GL (N = 160), respectively (difference -0.37% [95% CI: -0.50 to -0.23], P < .001); more patients on BIL achieved HbA1c <7% (44.9% vs 27.5%, P < .001). Compared with GL, patients using BIL lost weight, with lower fasting serum glucose and between-day fasting blood glucose variability, and 36% less nocturnal hypoglycemia, 29% more total hypoglycemia and more severe hypoglycemia. Total and prandial insulin doses were lower with BIL; basal insulin doses were higher. Alanine aminotransferase increased with BIL, with more patients having elevations ≥3 × ULN. BIL treatment was associated with more frequent injection site reactions and an increase from baseline in serum triglycerides.

CONCLUSIONS

In patients with type 1 diabetes, treatment with BIL compared to GL for 26 weeks was associated with lower HbA1c, less nocturnal hypoglycemia, lower glucose variability and weight loss. Increases in total and severe hypoglycemia, triglycerides, aminotransferases and injection site reactions were also noted.

Reduced peripheral activity leading to hepato-preferential action of basal insulin peglispro compared with insulin glargine in patients with type 1 diabetes

AIMS

Basal insulin peglispro (BIL), a novel PEGylated basal insulin with a large hydrodynamic size, has a delayed absorption and reduced clearance that prolongs the duration of action. The current study compared the effects of BIL and insulin glargine (GL) on endogenous glucose production (EGP), glucose disposal rate (GDR) and lipolysis in patients with type 1 diabetes.

MATERIALS AND METHODS

This was a randomized, open-label, four-period, crossover study. Patients received intravenous infusions of BIL and GL, each at two dose levels selected for partial and maximal suppression of EGP, during an 8 to 10 h euglycemic clamp procedure with d-[3-³ H] glucose.

RESULTS

Following correction for equivalent human insulin concentrations (EHIC), low-dose GL infusion resulted in similar EGP at the end of the clamp compared to low-dose BIL infusion (GL/BIL ratio of 1.03) but a higher GDR (GL/BIL ratio of 2.42), indicating similar hepatic activity but attenuated peripheral activity of BIL. Consistent with this, the EHIC-corrected GDR/EGP at the end of the clamp was 1.72-fold greater for GL than BIL following low-dose administration. At the lower dose of BIL and GL (concentrations in the therapeutic range), BIL produced less suppression of lipolysis compared with GL as indicated by free fatty acid and glycerol levels at the end of the clamp.

CONCLUSIONS

Compared with GL, BIL restored the hepato-peripheral insulin action gradient seen in normal physiology via its peripherally restricted action on target tissues related to carbohydrate and lipid metabolism.