Efficacy and safety of the glucagon-like peptide-1 receptor agonist liraglutide added to insulin therapy in poorly regulated patients with type 1 diabetes--a protocol for a randomised, double-blind, placebo-controlled study: the Lira-1 study

Efficacy and Safety of Tirzepatide in Adults With Type 1 Diabetes: A Proof of Concept Observational Study

BACKGROUND

Tirzepatide is approved by the United States Food and Drug Administration (FDA) for the management of type 2 diabetes. The efficacy and safety of this drug have not been studied in people with type 1 diabetes (T1D).

METHODS

In this single-center, retrospective, observational study, hemoglobin A1C (HbA1c), weight, body mass index (BMI), and continuous glucose monitoring (CGM) data were collected from electronic health records of adults with T1D at initiation of tirzepatide and at subsequent clinic visits over 8 months. Primary outcomes were reduction in HbA1c and percent change in body weight and secondary outcomes were change in CGM metrics and BMI over 8 months from baseline.

RESULTS

The mean (±SD) age of the 26 adults (54% female) with T1D was 42 ± 8 years with a mean BMI of 36.7 ± 5.3 kg/m2. There was significant reduction in HbA1c by 0.45% at 3 months and 0.59% at 8 months, and a significant reduction in body weight by 3.4%, 10.5%, and 10.1% at 3, 6, and 8 months after starting tirzepatide. Time in target range (TIR = 70-180 mg/dL) and time in tight target range (TITR = 70-140 mg/dL) increased (+12.6%, P = .002; +10.7%, P = .0016, respectively) and time above range (TAR >180 mg/dL) decreased (-12.6%, P = .002) at 3 months, and these changes were sustained over 8 months. The drug was relatively safe and well tolerated with only 2 patients discontinuing the medication.

CONCLUSIONS

Tirzepatide significantly reduced HbA1c and body weight in adults with T1D. A randomized controlled trial is needed to establish efficacy and safety of this drug in T1D.

Benefits and risks of drug combination therapy for diabetes mellitus and its complications: a comprehensive review

Diabetes is a chronic metabolic disease, and its therapeutic goals focus on the effective management of blood glucose and various complications. Drug combination therapy has emerged as a comprehensive treatment approach for diabetes. An increasing number of studies have shown that, compared with monotherapy, combination therapy can bring significant clinical benefits while controlling blood glucose, weight, and blood pressure, as well as mitigating damage from certain complications and delaying their progression in diabetes, including both type 1 diabetes (T1D), type 2 diabetes (T2D) and related complications. This evidence provides strong support for the recommendation of combination therapy for diabetes and highlights the importance of combined treatment. In this review, we first provided a brief overview of the phenotype and pathogenesis of diabetes and discussed several conventional anti-diabetic medications currently used for the treatment of diabetes. We then reviewed several clinical trials and pre-clinical animal experiments on T1D, T2D, and their common complications to evaluate the efficacy and safety of different classes of drug combinations. In general, combination therapy plays a pivotal role in the management of diabetes. Integrating the effectiveness of multiple drugs enables more comprehensive and effective control of blood glucose without increasing the risk of hypoglycemia or other serious adverse events. However, specific treatment regimens should be tailored to individual patients and implemented under the guidance of healthcare professionals.

GLP-1 receptor agonists in the treatment of type 2 diabetes - state-of-the-art

BACKGROUND

GLP-1 receptor agonists (GLP-1 RAs) with exenatide b.i.d. first approved to treat type 2 diabetes in 2005 have been further developed to yield effective compounds/preparations that have overcome the original problem of rapid elimination (short half-life), initially necessitating short intervals between injections (twice daily for exenatide b.i.d.).

SCOPE OF REVIEW

To summarize current knowledge about GLP-1 receptor agonist.

MAJOR CONCLUSIONS

At present, GLP-1 RAs are injected twice daily (exenatide b.i.d.), once daily (lixisenatide and liraglutide), or once weekly (exenatide once weekly, dulaglutide, albiglutide, and semaglutide). A daily oral preparation of semaglutide, which has demonstrated clinical effectiveness close to the once-weekly subcutaneous preparation, was recently approved. All GLP-1 RAs share common mechanisms of action: augmentation of hyperglycemia-induced insulin secretion, suppression of glucagon secretion at hyper- or euglycemia, deceleration of gastric emptying preventing large post-meal glycemic increments, and a reduction in calorie intake and body weight. Short-acting agents (exenatide b.i.d., lixisenatide) have reduced effectiveness on overnight and fasting plasma glucose, but maintain their effect on gastric emptying during long-term treatment. Long-acting GLP-1 RAs (liraglutide, once-weekly exenatide, dulaglutide, albiglutide, and semaglutide) have more profound effects on overnight and fasting plasma glucose and HbA1c, both on a background of oral glucose-lowering agents and in combination with basal insulin. Effects on gastric emptying decrease over time (tachyphylaxis). Given a similar, if not superior, effectiveness for HbA1c reduction with additional weight reduction and no intrinsic risk of hypoglycemic episodes, GLP-1RAs are recommended as the preferred first injectable glucose-lowering therapy for type 2 diabetes, even before insulin treatment. However, GLP-1 RAs can be combined with (basal) insulin in either free- or fixed-dose preparations. More recently developed agents, in particular semaglutide, are characterized by greater efficacy with respect to lowering plasma glucose as well as body weight. Since 2016, several cardiovascular (CV) outcome studies have shown that GLP-1 RAs can effectively prevent CV events such as acute myocardial infarction or stroke and associated mortality. Therefore, guidelines particularly recommend treatment with GLP-1 RAs in patients with pre-existing atherosclerotic vascular disease (for example, previous CV events). The evidence of similar effects in lower-risk subjects is not quite as strong. Since sodium/glucose cotransporter-2 (SGLT-2) inhibitor treatment reduces CV events as well (with the effect mainly driven by a reduction in heart failure complications), the individual risk of ischemic or heart failure complications should guide the choice of treatment. GLP-1 RAs may also help prevent renal complications of type 2 diabetes. Other active research areas in the field of GLP-1 RAs are the definition of subgroups within the type 2 diabetes population who particularly benefit from treatment with GLP-1 RAs. These include pharmacogenomic approaches and the characterization of non-responders. Novel indications for GLP-1 RAs outside type 2 diabetes, such as type 1 diabetes, neurodegenerative diseases, and psoriasis, are being explored. Thus, within 15 years of their initial introduction, GLP-1 RAs have become a well-established class of glucose-lowering agents that has the potential for further development and growing impact for treating type 2 diabetes and potentially other diseases.

The effects of metformin in type 1 diabetes mellitus

BACKGROUND

This retrospective study investigated the effect of adding metformin to pharmacologic insulin dosing in type 1 diabetics on insulin therapy 1 year after treatment compared with patients on insulin therapy alone.

METHODS

Twenty-nine adults with type 1 diabetes who had metformin added to their insulin therapy for 12 months were compared with 29 adults with type 1 diabetes who remained on insulin-alone therapy.

RESULTS

Fifty-eight patients with C peptide negative-type 1 diabetics (26 females, mean age: 29.01 ± 7.03 years, BMI: 24.18 ± 3.16 kg/m2) were analyzed. Age, sex, body weight, insulin dose requirement, plasma glucose (PG), blood pressure (BP), and lipids did not differ between groups before treatment (p > 0.05). Metabolic syndrome (44.8 vs 41.4%, p > 0.05) did not differ between the metformin-insulin and insulin alone groups before treatment. Metabolic syndrome was more decreased in the metformin-insulin group than in the insulin alone group after treatment (-8.9 ± 1.3 vs. 2.5 ± 0.6%, p = 0.028). Insulin dose requirement was lower in the metformin-insulin group than in the insulin alone group (-0.03 vs. 0.11 IU/kg/d, p = 0.006). Fasting PG (-26.9 ± 54.2 vs. 0.7 ± 29.5 mg/dL, p = 0.022) and postprandial PG (-43.1 ± 61.8 mg/dL vs. -3.1 ± 40.1 mg/dL, p = 0.010) was more decreased in the metformin-insulin group than in the insulin alone group. Body weight, lipids, and HbA1c did not differ between the groups (p > 0.05).

CONCLUSIONS

Metformin decreased glucose concentrations, reduced metabolic syndrome, as well as insulin dose requirement more than insulin therapy alone, 1 year after treatment. These results were independent of blood lipid improvement or weight loss, although on average weight remained decreased with metformin-insulin therapy, whereas the average weight increased with insulin therapy alone.

Pharmacological Treatment in Diabetes Mellitus Type 1 - Insulin and What Else?

The basis of treatment in autoimmune diabetes is insulin therapy; however, many clinical cases have proven that this method does not solve all problems. Trials of causal treatment including blocking the autoimmune processes and insulin-producing cells transplants were carried out. Those methods require more research to be concerned as efficient and safe ways of treatment in type 1 diabetes. The use of non-insulin adjunct treatment is a new trend. It has been successfully used in laboratories as well as clinical trials. Metformin is the most widely used drug, together with sodium-glucose co-transporters 2 (SGLT2) inhibitors, amylin analogues, glucagon-like peptide 1 (GLP-1) receptor agonists, and dipeptidyl peptidase-4 (DPP-4) inhibitors. The results of administration of these medicaments give good outcomes in patients with diabetes mellitus type 1. Most likely, in the near future, they will progressively be used in both adult and adolescent patients with type 1 diabetes. Further multicenter, randomized studies are required to evaluate the efficacy of treatment and long term safety of these drugs.

Effects of liraglutide on cardiovascular risk factors in patients with type 1 diabetes

We investigated the short-term effect of adding liraglutide 1.8 mg once daily to insulin treatment on cardiovascular risk factors in patients with type 1 diabetes. In total, 100 overweight (BMI ≥25 kg/m² ) adult patients (age ≥18 years) with type 1 diabetes and HbA1c ≥ 8% (64 mmol/mol) were randomized to liraglutide 1.8 mg or placebo added to insulin treatment in a 24-week double-blinded, placebo-controlled trial. At baseline and after 24 weeks of treatment, 24-hour blood pressure and heart rate, pulse pressure, pulse wave velocity and carotid intima-media thickness were evaluated. Compared with placebo, liraglutide increased 24-hour heart rate by 4.6 beats per minute (BPM); P = .0015, daytime heart rate by 3.7; P = .0240 and night-time heart rate by 7.5 BPM; P < .001 after 24 weeks. Diastolic nocturnal blood pressure increased by 4 mm Hg; P = .0362 in the liraglutide group compared with placebo. In conclusion, in patients with long-standing type 1 diabetes, liraglutide as add-on to insulin increased heart rate and did not improve other cardiovascular risk factors after 24 weeks of treatment.

Efficacy and safety of liraglutide for overweight adult patients with type 1 diabetes and insufficient glycaemic control (Lira-1): a randomised, double-blind, placebo-controlled trial

BACKGROUND

The combination of insulin and glucagon-like peptide-1 (GLP-1) receptor agonist therapy improves glycaemic control, induces weight loss, and reduces insulin dose needed in type 2 diabetes. We assessed the efficacy and safety of the GLP-1 receptor agonist liraglutide as an add-on therapy to insulin for overweight adult patients with type 1 diabetes.

METHODS

We did a randomised, double-blind, placebo-controlled trial at Steno Diabetes Center (Gentofte, Denmark). Patients aged 18 years or older with type 1 diabetes, insufficient glycaemic control (HbA1c >8% [64 mmol/mol]), and overweight (BMI >25 kg/m(2)) were randomly assigned (1:1) to receive insulin treatment plus either liraglutide or placebo (saline solution) by subcutaneous injection once per day. Randomisation was done in blocks of four. Treatment assignment was masked to investigators and patients. Treatment lasted 24 weeks and liraglutide was started at a dose of 0·6 mg per day, escalated to 1·2 mg per day after 1 week, and then again to 1·8 mg per day after another week. Intervals between dose increments could be extended at the discretion of the investigator. The primary endpoint was change in HbA1c from baseline to week 24. Secondary endpoints were changes in hypoglycaemic events, glycaemic variability, glycaemic excursions, insulin dose, bodyweight, postprandial plasma concentrations of glucagon and GLP-1, gastric emptying, blood pressure, heart rate, patient-reported outcome measures, time spent in hypoglycaemia, near-normoglycaemia, and hyperglycaemia, plasma fasting glucose, mean glucose, and cholesterol. Efficacy analyses were calculated by use of a mixed model, whereby a patient's data are used as long as the patient is in the study. The safety analyses were done in the intention-to-treat population, which consisted of all patients who received at least one dose of their randomly assigned study drug. This study is registered with ClinicalTrials.gov, number NCT01612468.

FINDINGS

Between July 10, 2012, and May 30, 2014, we enrolled 100 patients with type 1 diabetes, with 50 patients allocated liraglutide and 50 to placebo. Four patients from the liraglutide group and six patients from the placebo group discontinued treatment before 24 weeks. At the end of treatment, change in HbA1c from baseline did not differ between groups (-0·5%, 95% CI -0·8 to -0·4 [-6·0 mmol/mol, 95% CI -8·7 to -4·4] with liraglutide vs -0·3%, -0·6 to -0·2 [-4·0 mmol/mol, -6·6 to -2·3] with placebo; between-group difference -0·2% [-0·5 to 0·1; 2·2 mmol/mol, -5·5 to 1·1], p=0·1833). The number of hypoglycaemic events was reduced with liraglutide, with an incident rate ratio of 0·82 (95% CI 0·74 to 0·90). However, we detected no changes in glycaemic variability (continuous overall net glycaemic action per 60 min from 10·3 [95% CI 9·8 to 10·8] to 9·9 [9·2 to 10·6] in the liraglutide treated patients vs 10·2 [9·7 to 10·7] to 9·7 [9·1 to 10·3] in the placebo treated patients). Both bolus insulin (difference -5·8 IU, 95% CI -10·7 to -0·8, p=0·0227) and bodyweight (difference -6·8 kg, 95% CI -12·2 to -1·4, p=0·0145) decreased with liraglutide treatment compared with placebo. Heart rate increased with liraglutide, with a difference between groups of 7·5 bpm (95% CI 2·8-12·2, p=0·0019). Postprandial plasma glucagon and GLP-1 concentrations did not differ between groups (difference between groups at end of treatment: -408 mmol/L per 240 min [95% CI -941 to 125, p=0·1309] for glucagon and -266 mmol/L per 240 min [-1034 to 501, p=0·4899] for GLP-1). Gastric emptying was delayed after 3 weeks of treatment with liraglutide (19·9 min, 95% CI 0·8 to 39·0, p=0·0412), but we detected no difference after 24 weeks of treatment (-1·5 min, -20·5 to 17·6, p=0·8793). Patient-reported outcome measures differed between groups only with respect to perceived frequency of hypoglycaemia, which was higher with placebo, with a difference between groups of -0·6 (95% CI -1·1 to -0·07, p=0·0257). Liraglutide was associated with more frequent nausea (29 [58%] patients with liraglutide vs five [10%] with placebo), dyspepsia (11 [22%] patients with liraglutide vs one [2%] with placebo), diarrhoea (ten [20%] patients with liraglutide vs one [2%] with placebo), decreased appetite (seven patients [14%] with liraglutide vs none with placebo), and vomiting (seven [14%] patients with liraglutide vs one [2%] with placebo).

INTERPRETATION

In patients with type 1 diabetes, overweight, and insufficient glycaemic control, the reduction in HbA1c did not differ between insulin plus placebo and insulin plus liraglutide treatment. Liraglutide was associated with reductions in hypoglycaemic events, bolus and total insulin dose, and bodyweight, and increased heart rate.

FUNDING

Novo Nordisk.

GLP-1 receptor agonists in type 1 diabetes: a proof-of-concept approach

AIMS

To test potential efficacy of liraglutide, a GLP-1 receptor agonist, in subjects with type 1 diabetes (T1DM).

METHODS

We have recruited nine T1DM patients (age 40.1 ± 6.4 years, duration of diabetes 19.2 ± 8.8 years, BMI 24.3 ± 3.5 kg/m(2), HbA1c 8.2 ± 1.0 %-66 ± 11 mmol/mol, daily insulin dose: 0.6 ± 0.1 IU/kg) on continuous subcutaneous insulin therapy with undetectable C-peptide. In addition to existing treatment was administered in single-blind (a) therapy subcutaneously with 0.1 ml of saline solution for 3 days and (b) 0.1 ml of liraglutide (0.6 mg/day) for a further 3 days with daily glucose excursions recorded by continuous glucose monitoring.

RESULTS

Adding liraglutide resulted in a significant reduction in mean blood glucose (138 ± 29 vs. 163 ± 29 mg/dl, p < 0.0001) and standard deviation (42 ± 9 vs. 60 ± 15 mg/dl, p < 0.0001). The area under the curve (AUC) for blood glucose >140 mg/dl was also significantly reduced (22.2 ± 16.4 vs. 41.1 ± 19.7 mg/dl h, p < 0.05) with no difference in AUC for blood glucose <70 mg/dl (liraglutide 0.7 ± 0.9 mg/dl h; placebo: 0.8 ± 1.4 mg/dl h, p = NS). Finally, adding liraglutide reduced daily insulin requirement (37.5 ± 17.2 vs. 42.9 ± 22.4 UI/day, p < 0.01).

CONCLUSIONS

Short-term treatment with liraglutide, in T1DM, reduces average blood glucose, blood glucose variability and daily insulin requirement without increasing risk of hypoglycemia.

Twelve-Week Treatment With Liraglutide as Add-on to Insulin in Normal-Weight Patients With Poorly Controlled Type 1 Diabetes: A Randomized, Placebo-Controlled, Double-Blind Parallel Study

OBJECTIVE

This study investigated the efficacy and safety of once-daily liraglutide 1.2 mg versus placebo as add-on to insulin treatment in normal-weight patients with poorly controlled type 1 diabetes.

RESEARCH DESIGN AND METHODS

In a randomized (1:1), double-blind, placebo-controlled design, 40 patients with type 1 diabetes (HbA1c ≥8% [64 mmol/mol]) received once-daily liraglutide 1.2 mg or placebo for 12 weeks. Continuous glucose monitoring was performed before and at the end of treatment. The primary end point was change in HbA1c. Secondary end points included change in insulin dose, weight, glycemic excursions, heart rate, and blood pressure.

RESULTS

Baseline HbA1c was similar in the liraglutide and placebo group (8.8 ± 0.2 and 8.7 ± 0.1% [72.5 ± 2.2 and 71.8 ± 1.5 mmol/mol]). Change in HbA1c from baseline was -0.6 ± 0.2% (-6.22 ± 1.71 mmol/mol) with liraglutide and -0.5 ± 0.2% (-5.56 ± 1.67 mmol/mol) with placebo (P = 0.62). Variation in glycemic excursions did not change in either group. Change in body weight was -3.13 ± 0.58 and +1.12 ± 0.42 kg (P < 0.0001) with liraglutide and placebo, respectively. The bolus insulin dose decreased in liraglutide-treated patients and did not change with placebo treatment (4.0 ± 1.3 vs. 0.0 ± 1.0 IU, P = 0.02). Heart rate increased within the liraglutide group (P = 0.04) but not compared with placebo, whereas mean systolic blood pressure decreased compared with placebo (between-group difference 3.21 mmHg [95% CI -8.31 to 1.90], P = 0.04). Liraglutide was more frequently associated with gastrointestinal adverse effects. The incidence of hypoglycemia did not differ between groups.

CONCLUSIONS

Liraglutide significantly reduces body weight and insulin requirements but has no additional effect on HbA1c in normal-weight patients with type 1 diabetes inadequately controlled on insulin alone.

[Nonglycemic effects of incretins in patients with long-term type 1 diabetes mellitus and chronic kidney disease]

AIM

To investigate the nonglycemic effects of incretins in patients with type 1 diabetes mellitus (DM1) of long duration (for more than 20 years) and chronic kidney disease.

MATERIAL AND METHODS

Seventy-five patients with varying degrees of diabetic nephropathy (DN) and without this condition, including patients receiving renal replacement therapy with programmed hemodialysis and those who had undergone kidney transplantation were examined. The levels of phosphorus-calcium metabolic indicators (calcium, phosphorus, parathyroid hormone, vitamin D, and fibroblast growth factor 23 (FGF-23)), the cardiac damage marker atrial natriuretic peptide, the proinflammatory markers monocyte chemoattractant protein 1 (MCP-1) and C-reactive protein (CRP) and the fibrotic marker transforming growth factor-β, as well as those of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) were estimated in addition to conventional examination methods. All the patients underwent cardiac multislice spiral computed tomography, by calculating the Agatston index (calcium index (CI)) reflecting the degree of coronary artery calcification.

RESULTS

The investigation revealed no relationship of GLP-1 and GIP levels to the presence and degree of DN in the patients of the study groups. GLP-1 was noted to be inversely related to patient age, indicating the diminished secretion of this peptide in older people. There was evidence that GLP-1 positively affected blood lipid composition (total cholesterol: r=-0,320; p<0.05) and the magnitude of coronary artery calcification (CI: r=-0.308; p<0.05). GIP showed a differently directed effect on the proinflammatory factors: fibrinogen (r=-0.264; p<0.05), CRP (r=-0.626; p<0.05), and FGF-23 (r=-0.341; p<0.05).

CONCLUSION

The investigation has demonstrated the nonglycemic effects of incretins that favorably affect the pathogenetic processes underlying the late complications of DM1. The findings point to the potential efficacy of incretin-based drugs in preventing and treating the late complications of DM, which necessitates the conduction of larger investigations.