Pramlintide Research & Studies

People with type 1 diabetes (T1D) are usually considered to exclusively exhibit β-cell failure, but they frequently also feature insulin resistance. This review discusses the mechanisms, clinical features, and therapeutic relevance of insulin resistance by focusing mainly on human studies using gold-standard techniques (euglycemic-hyperinsulinemic clamp). In T1D, tissue-specific insulin resistance can develop early and sustain throughout disease progression. The underlying pathophysiology is complex, involving both metabolic- and autoimmune-related factors operating synergistically. Insulin treatment may play an important pathogenic role in predisposing individuals with T1D to insulin resistance. However, the established lifestyle-related risk factors and peripheral insulin administration inducing glucolipotoxicity, hyperinsulinemia, hyperglucagonemia, inflammation, mitochondrial abnormalities, and oxidative stress cannot always fully explain insulin resistance in T1D, suggesting a phenotype distinct from type 2 diabetes. The mutual interaction between insulin resistance and impaired endothelial function further contributes to diabetes-related complications. Insulin resistance should therefore be considered a treatment target in T1D. Aside from lifestyle modifications, continuous subcutaneous insulin infusion can ameliorate insulin resistance and hyperinsulinemia, thereby improving glucose toxicity compared with multiple injection insulin treatment. Among other concepts, metformin, pioglitazone, incretin-based drugs such as GLP-1 receptor agonists, sodium-glucose cotransporter inhibitors, and pramlintide can improve insulin resistance, either directly or indirectly. However, considering the current issues of high cost, side effects, limited efficacy, and their off-label status, these agents in people with T1D are not widely used in routine clinical care at present.

Precision diabetology is increasingly becoming diabetes phenotype-driven, whereby the specific hormonal imbalances involved are taken into consideration. Concomitantly, body weight-favorable therapeutic approaches are being dictated by the obesity pandemic, which extends to all diabetes subpopulations. Amylin, an anorexic neuroendocrine hormone co-secreted with insulin, is deficient in individuals with diabetes and plays an important role in postprandial glucose homeostasis, with additional potential cardiovascular and neuroprotective functions. Its actions include suppressing glucagon secretion, delaying gastric emptying, increasing energy expenditure and promoting satiety. While amylin holds promise as a therapeutic agent, its translation into clinical practice is hampered by complex receptor biology, the limitations of animal models, its amyloidogenic properties and pharmacokinetic challenges. In individuals with advanced β-cell dysfunction, supplementing insulin therapy with pramlintide, the first and currently only approved injectable short-acting selective analog of amylin, has demonstrated efficacy in enhancing both postprandial and overall glycemic control in both type 2 diabetes (T2D) and type 1 diabetes (T1D) without increasing the risk of hypoglycemia or weight gain. Current research focuses on several key strategies, from enhancing amylin stability by attaching polyethylene glycol or carbohydrate molecules to amylin, to developing oral amylin formulations to improve patients' convenience, as well as developing various combination therapies to enhance weight loss and glucose regulation by targeting multiple receptors in metabolic pathways. The novel synergistically acting glucagon-like peptide-1 (GLP-1) receptor agonist combined with the amylin agonist, CagriSema, shows promising results in both glucose regulation and weight management. As such, amylin agonists (combined with other members of the incretin class) could represent the elusive drug candidate to address the multi-hormonal dysregulations of diabetes subtypes and qualify as a precision medicine approach that surpasses the long overdue division into T1DM and T2DM. Further development of amylin-based therapies or delivery systems is crucial to fully unlock the therapeutic potential of this intriguing hormone.Graphical abstract available for this article.

The identification of amylin as a glucoregulatory peptide hormone with roles in meal-ending satiation sparked a surge of experimental development, which culminated in the amylin mimetic drug pramlintide. Pramlintide was approved by the FDA in 2005 for the treatment of type 1 diabetes mellitus and insulin-requiring type 2 diabetes, and was also explored as a novel anti-obesity treatment. Despite this exciting potential, efforts to develop an amylin-based anti-obesity therapeutic stalled owing to challenges around dosage frequency, safety and formulation. Generally, anti-obesity therapies have displayed modest efficacy and mixed safety profiles, leaving a clear unmet clinical need that requires addressing. Advances in peptide chemistry have reinvigorated the amylin field by enabling the manufacture of effective new amylin-based molecules, resulting in therapeutics that are now on the cusp of approval. At present, there are growing concerns around GLP1 receptor agonist-based therapeutics, in particular their association with loss of lean body mass. Additionally, treatment of patients with overweight or obesity without associated comorbidities is increasingly common. The widespread pharmacotherapy of otherwise healthy populations with overweight or obesity with the goal of improving future health requires further regulatory and ethical consideration. This Review describes how amylin controls energy homeostasis and provides a current overview of amylin-based therapeutic development.

The International Society for Pediatric and Adolescent Diabetes (ISPAD) guidelines represent a rich repository that serves as the only comprehensive set of clinical recommendations for children, adolescents, and young adults living with diabetes worldwide. This chapter builds on the 2022 ISPAD guidelines, and updates recommendations on the principles of intensive insulin regimens, including more intensive forms of multiple daily injections with new-generation faster-acting and ultra-long-acting insulins; a summary of adjunctive medications used alongside insulin treatment that includes details on pramlintide, metformin, glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RA) and sodium-glucose cotransporter inhibitors; and key considerations with regard to access to insulin and affordability to ensure that all persons with diabetes who need insulin can obtain it without financial hardship.

Obesity is an epidemic in the United States with serious concomitant co-morbid conditions; people living with type 1 diabetes mellitus (T1D) are not immune to the risk either. Weight gain in T1D is likely multifactorial, due to genetic, environmental and treatment-related factors. FDA-approved and other adjunctive weight loss therapies may benefit people living with T1D but there are risks to consider when providing recommendations or prescribing medications.

Dysregulation of various glucoregulatory hormones lead to failure of insulin monotherapy in patients with diabetes mellitus due to various reasons, including severe hypoglycemia, glycemic hypervariability, and an increased risk of microvascular complications. However, pramlintide as an adjunct to insulin therapy enhances glucagon suppression and thereby offers improved glycemic control. Clinical studies have shown that pramlintide improves glycemic control, reduces postprandial glucose excursions, and promotes weight loss in patients with type 1 and type 2 diabetes. Although clinical benefits of pramlintide are well reported, there still exists a high patient resistance for the therapy, as separate injections for pramlintide and insulin must be administered. Although marketed insulin formulations generally demonstrate a peak action in 60-90 minutes, pramlintide elicits its peak concentration at around 20-30 minutes after administration. Thus, owing to the significant differences in pharmacokinetics of exogenously administered pramlintide and insulin, the therapy fails to elicit its action otherwise produced by the endogenous hormones. Hence, strategies such as delaying the release of pramlintide by using inorganic polymers like silica, synthetic polymers like polycaprolactone, and lipids have been employed. Also, approaches like noncovalent conjugation, polyelectrolyte complexation, and use of amphiphilic excipients for codelivery of insulin and pramlintide have been explored to address the issues with pramlintide delivery and improve patient adherence to the therapy. This approach may usher in a new era of diabetes management, offering patients multiple options to tailor their treatment and improve their quality of life. SIGNIFICANCE STATEMENT: To our knowledge, this is the first report that summarizes various challenges in insulin and pramlintide codelivery and strategies to overcome them. The paper also provides deeper insights into various novel formulation strategies for pramlintide that could further broaden the reader's understanding of peptide codelivery.

The aim of this study was to examine the hypothesis that pramlintide would reduce hypoglycaemia by slowing gastric emptying and reducing postprandial glucagon secretion, thus limiting postprandial glycaemic excursions and insulin secretion, and thus to determine the efficacy of pramlintide on frequency and severity of hypoglycaemia in post-bariatric hypoglycaemia (PBH).

The role of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) in the treatment of type 1 diabetes mellitus (T1DM), including efficacy and safety evidence, is reviewed.

Amylin is a pancreatic β-cell hormone that produces effects in several different organ systems. Here, we review the literature in rodents and in humans on amylin research since its discovery as a hormone about 25 years ago. Amylin is a 37-amino-acid peptide that activates its specific receptors, which are multisubunit G protein-coupled receptors resulting from the coexpression of a core receptor protein with receptor activity-modifying proteins, resulting in multiple receptor subtypes. Amylin's major role is as a glucoregulatory hormone, and it is an important regulator of energy metabolism in health and disease. Other amylin actions have also been reported, such as on the cardiovascular system or on bone. Amylin acts principally in the circumventricular organs of the central nervous system and functionally interacts with other metabolically active hormones such as cholecystokinin, leptin, and estradiol. The amylin-based peptide, pramlintide, is used clinically to treat type 1 and type 2 diabetes. Clinical studies in obesity have shown that amylin agonists could also be useful for weight loss, especially in combination with other agents.

Postprandial glucose excursions negatively affect glycemic control and markers of cardiovascular health. Pramlintide, an amylinomimetic, is approved for treatment of elevated postprandial glucose levels in type 1 and type 2 diabetes mellitus.

Pramlintide has a high molecular weight, so it is unlikely to pass into breastmilk in clinically important amounts. It also has a short half-life and it is a peptide that is likely digested in the infant's gastrointestinal tract, so it is unlikely to reach the clinically important levels in infant serum. However, because no information is available on the use of pramlintide during breastfeeding an alternate drug may be preferred, especially while nursing a newborn or preterm infant. Monitor breastfed infants for signs of hypoglycemia such as jitteriness, excessive sleepiness, poor feeding, seizures cyanosis, apnea, or hypothermia. If there is concern, monitoring of the breastfed infant's blood glucose is advisable during maternal therapy with pramlintide.[1]

Recognizing that type 1 diabetes was characterized not only by insulin deficiency, but also by amylin deficiency, Cooper (Cooper, 1991) predicted that certain features of the disease could be related thereto, and he proposed amylin/insulin co-replacement therapy. Although the early physiological rationale was flawed, the idea that glucose control could be improved over that attainable with insulin alone without invoking the ravages of worsening insulin-induced hypoglycemia was vindicated. The proposal spawned a first-in-class drug development program that ultimately led to marketing approval by the U.S. Food and Drug Administration of the amylinomimetic pramlintide acetate in March 2005. The prescribers' package insert (Amylin Pharmaceuticals Inc., 2005), which includes a synopsis of safety and efficacy of pramlintide, is included as Appendix 1. Pramlintide exhibited a terminal t1/2, in humans of 25-49 min and, like amylin, was cleared mainly by the kidney. The dose-limiting side effect was nausea and, at some doses, vomiting. These side effects usually subsided within the first days to weeks of administration. The principal risk of pramlintide co-therapy was an increased probability of insulin-induced hypoglycemia, especially at the initiation of therapy. This risk could be mitigated by pre-emptive reduction in insulin dose. Pramlintide dosed at 30-60 microg three to four times daily in patients with type 1 diabetes, and at doses of 120 microg twice daily in patients with type 2 diabetes, invoked a glycemic improvement, typically a decrease in HbA1c of 0.4-0.5% relative to placebo, that was sustained for at least 1 year. This change relative to control subjects treated with insulin alone typically was associated with a reduction in body weight and insulin use, and was not associated with an increase in rate of severe hypoglycemia other than at the initiation of therapy. Effects observed in animals, such as slowing of gastric emptying, inhibition of nutrient-stimulated glucagon secretion, and inhibition of food intake, generally have been replicated in humans. A notable exception appears to be induction of muscle glycogenolysis and increase in plasma lactate.

The pharmacology, pharmacokinetics, clinical efficacy, adverse effects, and dosage and administration of pramlintide are reviewed.

While lifestyle changes such as dietary modification and increased physical activity can be very effective in improving glycemic control, over the long-term most individuals with Type 2 diabetes (T2DM) will require medications to achieve and maintain glycemic control. The purpose of this chapter is to provide the healthcare practitioner with an overview of the existing oral and injectable (non-insulin) pharmacological options available for the treatment of patients with T2DM. Currently, there are ten classes of orally available pharmacological agents to treat T2DM: 1) sulfonylureas, 2) meglitinides, 3) metformin (a biguanide), 4) thiazolidinediones (TZDs), 5) alpha glucosidase inhibitors, 6) dipeptidyl peptidase IV (DPP-4) inhibitors, 7) bile acid sequestrants, 8) dopamine agonists, 9) sodium-glucose transport protein 2 (SGLT2) inhibitors and 10) oral glucagon like peptide 1 (GLP-1) receptor agonists. In addition, glucagon like peptide 1 (GLP-1) receptor agonists, dual GLP-1 receptor and GIP receptor agonists, and pramlintide can be administered by injection. Medications from these distinct classes of pharmaceutical agents may be used as treatment by themselves (monotherapy) or in a combination of 2 or more drugs from multiple classes with different mechanisms of action. A variety of fixed combinations of 2 agents are available in the US and in many other countries. In this chapter we discuss the administration, mechanism of action, effect on glycemic control, other benefits, side effects, and the contraindications of the use of these glucose lowering drugs. For complete coverage of all related areas of Endocrinology, please visit our on-line FREE web-text, WWW.ENDOTEXT.ORG.

Insulin resistance in liver and muscle tissue, together with beta-cell secretory defects, leads to overt type 2 diabetes mellitus. In the early stages of this progressive disorder, glycaemic control can be established through diet and exercise alone. Indeed, in some patients, marked weight reduction can lead to normalized fasting blood glucose. As a consequence, pharmacological approaches to weight loss have been investigated as a new option for the management of type 2 diabetes in obese patients. The serotonin- and noradrenaline-reuptake inhibitor sibutramine has emerged as the most promising agent in the treatment of obesity, although it appears to be less effective in diabetic patients than in non-diabetic patients. Other weight-reducing agents of potential benefit include noradrenergic anorexiants, orlistat, leptin, and beta3-agonists. Insulin and insulin secretagogues, the oldest available antidiabetic drugs, have been used to compensate for beta-cell secretory defects in patients with type 2 diabetes. Repaglinide, a new, fast-acting insulin secretagogue with a short duration of action, reduces postprandial hyperglycaemia when taken shortly before meals. Other novel antidiabetic agents are currently under development, including pramlintide (an amylin analogue) and glucagon-like peptide. Pramlintide slows gastric emptying and delays glucose absorption, and glucagon-like peptide is the most potent endogenous stimulator of glucose-induced insulin release. Recent advances in type 2 diabetes therapy have seen the development of the thiazolidinediones (troglitazone, rosiglitazone, and pioglitazone), which improve insulin resistance in patients whose diabetes is poorly controlled by diet and exercise therapy. Thiazolidinediones bind to peroxisome proliferator-activated receptor-gamma (PPAR-gamma) and act through a process involving gene regulation at a transcriptional level. Troglitazone, the first approved drug in the class, has been shown to decrease plasma glucose levels as monotherapy but is more effective in combination with sulphonylureas, metformin, or insulin. However, despite its generally good safety profile, troglitazone has been associated with severe idiosyncratic hepatocellular injury. There have been more than 150 spontaneous reports of serious hepatic events, including at least 25 instances in which patients died or required a liver transplant. Rosiglitazone, the most potent thiazolidinedione, is still in clinical development, as is pioglitazone. To date, rosiglitazone has been shown to have no reported cases of idiosyncratic drug reactions leading to jaundice or liver failure and no clinically significant drug interactions with cytochrome P450 3A4-metabolized drugs such as nifedipine. Although the available data for pioglitazone are limited to the results of short-term studies, it is reported to be safe and well tolerated. Combination therapy is increasingly important in type 2 diabetes management following failure of monotherapy because complementary mechanisms of action of the different classes of oral agents demonstrate synergistic effects when used in combination. Oral agents may also be used as adjuncts to insulin for achieving glycaemic control.