Long-term (52-week) efficacy and safety of ipragliflozin add-on therapy to insulin in Japanese patients with type 1 diabetes mellitus: An uncontrolled, open-label extension of a phase III study

Glucagon secretion and its association with glycaemic control and ketogenesis during sodium-glucose cotransporter 2 inhibition by ipragliflozin in people with type 1 diabetes: Results from the multicentre, open-label, prospective study

AIM

Clinical trials showed the efficacy of sodium-glucose cotransporter 2 inhibitors for type 1 diabetes (T1D) by significant reductions in body weight and glycaemic variability, but elevated susceptibility to ketoacidosis via elevated glucagon secretion was a potential concern. The Suglat-AID evaluated glucagon responses and its associations with glycaemic control and ketogenesis before and after T1D treatment with the sodium-glucose cotransporter 2 inhibitor, ipragliflozin.

METHODS

Adults with T1D (n = 25) took 50-mg open-labelled ipragliflozin daily as adjunctive to insulin. Laboratory/clinical data including continuous glucose monitoring were collected until 12 weeks after the ipragliflozin initiation. The participants underwent a mixed-meal tolerance test (MMTT) twice [before (first MMTT) and 12 weeks after ipragliflozin treatment (second MMTT)] to evaluate responses of glucose, C-peptide, glucagon and β-hydroxybutyrate.

RESULTS

The area under the curve from fasting (0 min) to 120 min (AUC0-120min) of glucagon in second MMTT were significantly increased by 14% versus first MMTT. The fasting and postprandial β-hydroxybutyrate levels were significantly elevated in second MMTT versus first MMTT. The positive correlation between postprandial glucagon secretion and glucose excursions observed in first MMTT disappeared in second MMTT, but a negative correlation between fasting glucagon and time below range (glucose, <3.9 mmol/L) appeared in second MMTT. The percentage changes in glucagon levels (fasting and AUC0-120min) from baseline to 12 weeks were significantly correlated with those in β-hydroxybutyrate levels.

CONCLUSIONS

Ipragliflozin treatment for T1D increased postprandial glucagon secretion, which did not exacerbate postprandial hyperglycaemia but might protect against hypoglycaemia, leading to reduced glycaemic variability. The increased glucagon secretion might accelerate ketogenesis when adequate insulin is not supplied.

The emergence of obesity in type 1 diabetes

Obesity, a chronic low-grade inflammatory disease represented by multifactorial metabolic dysfunctions, is a significant global health threat for adults and children. The once-held belief that type 1 diabetes is a disease of people who are lean no longer holds. The mounting epidemiological data now establishes the connection between type 1 diabetes and the subsequent development of obesity, or vice versa. Beyond the consequences of the influx of an obesogenic environment, type 1 diabetes-specific biopsychosocial burden further exacerbates obesity. In the course of obesity management discussions, recurring challenges surfaced. The interplay between weight gain and escalating insulin dependence creates a vicious cycle from which patients struggle to break free. In the absence of weight management guidelines and regulatory approval for this population, healthcare professionals must navigate the delicate balance between benefits and risks. The gravity of this circumstance highlights the importance of bringing these topics to the forefront. In this Review, we discuss the changing trends and the biopsychosocial aspects of the intersection between type 1 diabetes and obesity. We highlight the evidence supporting the therapeutic means (i.e., exercise therapy, nutritional therapy, adjunct pharmacotherapy, and bariatric surgery) and directions for establishing a more robust and safer evidence-based approach.

Glucose-Lowering Therapy beyond Insulin in Type 1 Diabetes: A Narrative Review on Existing Evidence from Randomized Controlled Trials and Clinical Perspective

Background: In Type 1 diabetes (T1D), according to the most recent guidelines, the everyday glucose-lowering treatment is still restricted to the use of subcutaneous insulin, while multiple therapeutic options exist for Type 2 diabetes (T2D). Methods: For this narrative review we unsystematically screened PubMed and Embase to identify clinical trials which investigated glucose-lowering agents as an adjunct to insulin treatment in people with T1D. Published studies up to March 2022 were included. We discuss the safety and efficacy in modifying cardiovascular risk factors for each drug, the current status of research, and provide a clinical perspective. Results: For several adjunct agents, in T1D, the scientific evidence demonstrates improvements in HbA1c, reductions in the risk of hypoglycemia, and achievements of lower insulin requirements, as well as positive effects on cardiovascular risk factors, such as blood lipids, blood pressure, and weight. As the prevalence of obesity, the major driver for double diabetes, is rising, weight and cardiovascular risk factor management is becoming increasingly important in people with T1D. Conclusions: Adjunct glucose-lowering agents, intended to be used in T2D, bear the potential to beneficially impact on cardiovascular risk factors when investigated in the T1D population and are suggested to be more extensively considered as potentially disease-modifying drugs in the future and should be investigated for hard cardiovascular endpoints.

Do the benefits of sodium-glucose cotransporter 2 inhibitors exceed the risks in patients with type 1 diabetes?

Sodium-glucose cotransporter 2 inhibitors (SGLT2is) are well-established means of improving glycemia and preventing cardio-renal events in patients with type 2 diabetes. However, their efficacy and safety have yet to be fully characterized in patients with type 1 diabetes (T1D). We studied patients with T1D who regularly attended one of five diabetes centers and treated with an SGLT2i (ipragliflozin or dapagliflozin) for >52 weeks, and the changes in HbA1c, body mass, insulin dose, and laboratory data were retrospectively evaluated and adverse events (AEs) recorded during December 2018 to April 2021. A total of 216 patients with T1D were enrolled during the period. Of these, 42 were excluded owing to short treatment periods and 15 discontinued their SGLT2i. The mean changes in glycated hemoglobin (HbA1c), body mass, and insulin dose were -0.4%, -2.1 kg, and -9.0%, respectively. The change in HbA1c was closely associated with the baseline HbA1c (p < 0.001), but not with the baseline body mass or renal function. The basal and bolus insulin doses decreased by 18.2% and 12.6%, respectively, in participants with a baseline HbA1c <8%. The most frequent AE was genital infection (2.8%), followed by diabetic ketoacidosis (DKA; 1.4%). None of the participants experienced severe hypoglycemic events. In conclusion, the administration of an SGLT2i in addition to intensive insulin treatment in patients with T1D improves glycemic control and body mass, without increasing the incidence of hypoglycemia or DKA.

Efficacy and safety of adding ipragliflozin to insulin in Japanese patients with type 1 diabetes mellitus: a retrospective study

Advances in insulin preparations and administration methods have produced a gradual improvement in glycemic control in patients with type 1 diabetes mellitus (DM). Nevertheless, glycated hemoglobin (HbA1c) levels in patients with type 1 DM are still poor compared to those in patients with type 2 DM. Here, we sought to assess the efficacy and safety of the sodium-glucose cotransporter 2 (SGLT2) inhibitor ipragliflozin (IPRA) in patients with type 1 DM. This study was retrospectively conducted with data from type 1 DM patients who had a history of IPRA therapy. The primary endpoint was HbA1c level at 24 weeks. The baseline characteristics of a total of 12 subjects were as follows: age, 50.1 ± 13.2 years; diabetes duration, 17.3 ± 10.5 years; body mass index (BMI), 22.9 ± 2.1 kg/m²; HbA1c, 8.8 ± 1.3%; and daily insulin dose, 0.60 ± 0.21 units/kg. IPRA decreased HbA1c levels to 8.2 ± 1.2% (p < 0.05) and reduced insulin dose to 0.52 ± 0.17 units/kg (p < 0.01) after 24 weeks. HbA1c value was particularly reduced in subjects with preserved C-peptide index. IPRA significantly reduced body weight by -1.4 ± 1.4 kg (p < 0.01) 16 weeks after starting treatment, with no further weight loss after 24 weeks. There were no instances of diabetic ketoacidosis or severe hypoglycemia. IPRA exerted beneficial effects on glycemic control without any severe adverse effects, and should be safe and effective when used in patients with type 1 DM with understanding of correspondence in sick day.

Sodium/glucose cotransporter 2 inhibitors for the treatment of type 1 diabetes: what are the latest developments?

Despite the improvements in insulin therapy, many patients with type 1 diabetes mellitus (T1DM) do not achieve glycemic targets. Hypoglycemia and weight gain are important barriers in reaching these targets. Sodium/glucose cotransporter 2 (SGLT2) inhibitors lack these side effects and have an insulin-independent mechanism of action. Therefore, they might be useful in patients with T1DM. The authors discuss the safety and efficacy of SGLT2 inhibitors in T1DM. Several randomized controlled trials have evaluated dapagliflozin, sotagliflozin and empagliflozin in this population whereas fewer data are available for other members of this class. In these studies, SGLT2 inhibitors reduced HbA_1c levels and body weight without a greater risk of hypoglycemia. However, a higher incidence of diabetic ketoacidosis (DKA) was observed in patients treated with these agents. SGLT2 inhibitors improve glycemic control in patients with T1DM but this effect is modest. Even though weight loss and the neutral effect on the incidence of hypoglycemia are advantages of these agents, the increased risk of DKA is a cause of concern. Overall, SGLT2 inhibitors should be used with caution and only in carefully selected patients with T1DM who are motivated, adherent to treatment, well-trained in recognizing DKA and are closely followed-up.

Sodium-Glucose Transporter Inhibition in Adult and Pediatric Patients with Type 1 Diabetes Mellitus

Adjunctive therapies to insulin for treatment of type 1 diabetes mellitus (T1D) have gained popularity in efforts to achieve glycemic targets, and sodium-glucose transporter (SGLT) inhibitors are an appealing option due to associated weight loss, low risk of hypoglycemia, and improved cardiorenal outcomes seen in persons with type 2 diabetes mellitus. The increased risk of diabetic ketoacidosis (DKA), including euglycemic DKA, has led many to be wary of their use in T1D, especially given limited pediatric data and data regarding cardiorenal protection in this population. The phase 3 trials of these agents in T1D have yielded lower HbA1c, decreased total daily insulin dose, and small but significant weight loss with no increase in hypoglycemia. These trials also reported increased risks of genital mycotic infection and DKA. SGLT inhibitors have been approved as adjunctive therapy to insulin in adults with T1D in Europe and Japan, but the United States Food and Drug Administration has rejected similar applications. Although approaches to mitigate the risk of DKA have been developed, no randomized trials using such tools have been conducted. More research is needed to minimize the risk of DKA and to better evaluate the cardiorenal impact of these agents in persons with T1D.