Biosimilars and New Insulin Versions

Objective: To provide clinicians with an overview of similar biologic products including biosimilars and new insulin versions available in the U.S. and of key issues associated with such products, including differences in manufacturing and regulatory approaches and their impact on clinical use.Methods: We reviewed the relevant clinical and regulatory literature.Results: Patent protections for many biologics including several insulin preparations have or will expire shortly. This opens the door for new insulin versions to enter the U.S. and global marketplace. The development, manufacturing, and approval process for similar biologic products is more complex than for generic versions of small molecules. Most similar biologic products in the U.S. will be submitted for approval under section 351(k), a newly created biosimilar regulatory pathway. However, some biologics, including new insulin versions, will be submitted via the existing 505(b) regulatory pathway. These regulatory pathways have implications for how such products may be labeled, how they may be dispensed, and how patients may perceive them. The immunogenicity of biologics can affect safety and efficacy and can be altered through subtle changes in manufacturing. With the arrival of new insulin versions, health care providers will need to understand the implications of interchangeability, therapeutic equivalence, substitution, switching, and new delivery devices.Conclusion: An understanding of the above topics will be important as physicians, payers, and patients choose between similar versions of a reference listed biologic product.Abbreviations:BLA = biologics license applicationBPCIA = Biologics Price Competition and Innovation ActEU = European UnionFDA = Food and Drug AdministrationINN = international nonproprietary nameNDA = new drug applicationPD = pharmacodynamicPK = pharmacokineticPRCA = pure red cell aplasia     

Worldwide experience with biosimilar development

Limited access for high-quality biologics due to cost of treatment constitutes an unmet medical need in the United States (US) and other regions of the world. The term “biosimilar” is used to designate a follow-on biologic that meets extremely high standards for comparability or similarity to the originator biologic drug that is approved for use in the same indications. Use of biosimilar products has already decreased the cost of treatment in many regions of the world, and now a regulatory pathway for approval of these products has been established in the US. The Food and Drug Administration (FDA) led the world with the regulatory concept of comparability, and the European Medicines Agency (EMA) was the first to apply this to biosimilars. Patents on the more complex biologics, especially monoclonal antibodies, are now beginning to expire and biosimilar versions of these important medicines are in development. The new Biologics Price Competition and Innovation Act allows the FDA to approve biosimilars, but it also allows the FDA to lead on the formal designation of interchangeability of biosimilars with their reference products. The FDA’s approval of biosimilars is critical to facilitating patient access to high-quality biologic medicines, and will allow society to afford the truly innovative molecules currently in the global biopharmaceutical industry’s pipeline.     

Worldwide experience with biosimilar development

Limited access for high-quality biologics due to cost of treatment constitutes an unmet medical need in the US and other regions of the world. The term “biosimilar” is used to designate a follow-on biologic that meets extremely high standards for comparability or similarity to the originator biologic drug that is approved for use in the same indications. Use of biosimilar products has already decreased the cost of treatment in many regions of the world and now a regulatory pathway for approval of these products has been established in the US. The Food and Drug Administration (FDA) led the world with the regulatory concept of comparability and the European Medicines Agency (EMA) was the first to apply this to biosimilars. Patents on the more complex biologics, especially monoclonal antibodies, are now beginning to expire and biosimilar versions of these important medicines are in development. The new Biologics Price Competition and Innovation Act (BPCIA) allows the FDA to approve biosimilars and allows the FDA to lead on the formal designation of interchangeability of biosimilars with their reference products. The FDA''s approval of biosimilars is critical to facilitating patient access to high-quality biologic medicines and will allow society to afford the truly innovative molecules currently in the global biopharmaceutical industry''s pipeline.Key words: monoclonal antibodies (mAbs), biosimilars, recombinant biopharmaceuticals     

Follow-on Biologics: A New Play for Big Pharma: Healthcare 2010

The U.S. pharmaceutical industry plays a vital role in shaping the face of American healthcare. As an industry rooted in innovation, its continued evolution is inherent. With major patent expirations looming and thin product pipelines, the industry now must consider new directions to maintain growth and stability. Follow-on biologics, derived from living organisms and marketed after the patent expiration of similar therapies, represent a growing opportunity for big pharmaceutical firms, as discussed during Yale’s Healthcare 2010 conference in April. Key characteristics of follow-on biologics make them a worthwhile investment for big pharma companies: They command high prices, will likely have fewer entrants than generics due to high barriers to entry, and play to the existing strengths of big pharma firms. With the recent healthcare legislation providing the way for consistent Food and Drug Administration (FDA) regulation, the timing seems right to continue the push into this new and growing market.At a time when healthcare issues are on the mind of every American, it would serve us well to consider the future of one of the most influential players in the sector: pharmaceutical companies. National health expenditures for pharmaceutical products are hovering around 10 percent, meaning that one out of every 10 dollars that we, as a nation, spend on healthcare goes toward drugs. These drugs regulate our cholesterol levels, promote the growth of white blood cells in cancer patients, manage our restless leg syndrome, help us sleep better at night, and provide myriad other benefits to our health and well-being. Yet, for all the benefits that the pharmaceutical industry provides, it is also criticized by many for the expense of its products and the high profit margins that these products command. The growing popularity of biologics — treatments derived from living organisms, such as antibodies and interleukins — has particularly increased the price of drugs in the United States. The current price of the average biologic is more than 20 times that of a traditional, chemically synthesized small-molecule drug. There is a trade-off between high prices and innovative new therapies. Moreover, pharmaceutical companies themselves argue justifiably that prices account not only for the price of production, but also for the research and development (R&D) for that therapy as well as numerous others that did not make it all the way through the regulatory process and to the clinic.In recent years, we have witnessed the breakdown of the well-oiled innovation machinery of the traditional big pharma company. While R&D departments spent more and more (well over $1B per drug), they did not see promising results in the form of late-stage drug candidates [1]. Over time, this led to a strategic shift in portfolio management within big pharma companies toward an acquisition-heavy plan to build up their pipeline of drugs. In-house R&D projects were cut, and layoffs of scientific staff were rampant. This phenomenon continues, with 2009 bearing witness to the most mergers and acquisitions in the pharmaceutical industry to date. Industry-wide consolidation aimed to find complementary development projects and synergies in manufacturing and emerging markets. What has been the effect of all of this? The answer is not as hopeful as the pharmaceutical industry would have liked. A giant “patent cliff” still persists, referring to a number of blockbuster drugs that will go off patent over the next two years and cause a dramatic decrease in sales for big pharma firms. Without a strong pipeline to fill in the valley with new product sales, big pharma companies have begun scrambling to find new ways to generate revenue.Meanwhile, the biotech industry’s foray into therapeutics has been a wild success story. From the 1980s to the present, biologics have reshaped the face of medicine in many disease areas. The spawn of highly innovative, nimble biotech firms, biologic drugs are large, complex molecules grown in living cells rather than synthesized chemically like small molecules. For example, Enbrel is a fusion protein that acts as a tumor necrosis factor (TNF) inhibitor to stop inflammation. This drug is being widely prescribed for rheumatoid arthritis as well as psoriasis, among other indications, with sales last year reaching $5.9 billion, up 9.3 percent from 2008 [2]. Enbrel was first developed by Immunex and released in 1998. Immunex was acquired by a rival biotech firm, Amgen, in 2001 [3], and subsequent marketing of the drug in the United States was jointly undertaken by Amgen and Wyeth (now taken over by Pfizer in the mega-merger of 2009). Enbrel’s is the classic story of the modern biologic: a novel therapy developed at a small biotech firm and acquired or licensed up the food chain to feed bigger firms’ appetites for late-stage assets.Enbrel is by no means unique; there are many blockbuster biologics on the market. Like Enbrel, many of them will reach the end of their patent life soon. Enbrel’s patent expiration is set for 2012, at which time it will be exposed to potential competition from generic versions. Therefore, though there are many novel biologics therapies that can provide new ways of treating patients, there is also a huge opportunity for generic versions of biologics that did not exist even one decade ago. This opportunity is hard to quantify, but one recent estimate shows that biologics responsible for $20B in annual sales will go off patent by 2015 [4]. Unsurprisingly, small-molecule generics firms are flocking to this space. Teva, the world’s largest generics manufacturer, has partnered with the Lonza Group to make and sell so-called follow-on biologics. These treatments are similar, but not identical, to preceding biologics whose patents expired. Meanwhile, Novartis’s generics arm, Sandoz, has increased capacity in biomanufacturing to ramp up its efforts. Big pharma itself has made motions of interest in the business of follow-on biologics, as witnessed by the dedicated division of Merck, BioVentures, established in late 2008 for the development of follow-on biologics. Interestingly, even Pfizer is testing a follow-on version of Enbrel, now in phase 2 clinical trials [5]. With a big market opportunity and a number of firms interested, follow-on biologics will surely play an important role in shaping the future of the pharma industry.For large pharmaceutical firms, what is needed is a way to diversify and mitigate risk, a way to supplement their rollercoaster sales figures year after year. Follow-on biologics may be a smart play for big pharma companies. Like their generic cousins, biologics manufacturing has strong economies of scale that big pharma firms can leverage. But unlike generics, there are higher barriers to entry because of the technical challenges of manufacturing biologics and the necessary clinical proofs of equivalency. Pharmaceutical companies already are practiced at navigating the global clinical-trials arena and should be able to exercise a significant competitive advantage in this area, especially over the existing generics manufacturers attempting a play in the follow-on biologics market. It has been estimated that the investment necessary to bring a follow-on biologic to market is eight to 10 years and will cost $100-$200M [6]. This investment of time and capital is substantial and tends to favor larger firms with significant R&D budgets. However, to put the investment into perspective, this is only one-tenth of the cost of developing a full-scale innovative pharmaceutical product and has less associated risk of failure — a proposition that the big pharma industry should find appealing. Additionally, the trend for current follow-on biologics on the market in the European Union (EU) and United States has been to use traditional detailing and marketing practices to compete with branded products. This, too, puts big pharma at a competitive advantage over other players lacking an army of detailing pharmaceutical reps, who can use their established relationships with doctors and medical personnel to promote new follow-on biologics.One counter-argument to the case for a move into follow-on biologics is that the new healthcare reform, the Patient Protection and Affordable Care Act (PPACA), passed in March of this year will harm any would-be generic biologics makers with its 12-year exclusivity for branded biologics. However, while this length of time is significantly longer than the proposed five years that generics proponents pushed for, the surety of a secure path forward through the FDA for follow-on biologics outweighs the downside of lengthy biologics exclusivity. It is reasonable to hope that within two to three years, the FDA will have functional guidelines for the regulation of this nascent market. Now more than at any other time in the past, the ambiguity associated with government regulation is manageable. And if big pharma becomes more intentional about entering the follow-on biologics market, its powerful lobby, PhRMA, could influence the way that the details of the FDA regulations are written.If the pharma industry does find the follow-on biologics market appealing and makes a bet on it for supplementary revenue, what can we expect from the patient perspective? It could mean greater access at cheaper prices, but the dynamics are much more nuanced. The economics of the small-molecule generics market likely will not be transferrable to the follow-on biologics market. High barriers to entry, high fixed costs of manufacturing, and marketing expenses will more likely manifest themselves in a market that has a small number of firms with relatively small price drops upon introduction of follow-on therapies. In small-molecule generics, the price typically decreases by about 80 percent from the original branded drug price after one year of generic competition. However, in current follow-on markets in the EU, this has not been the case. Since its introduction of biosimilars regulation in 2004, the EU has successfully introduced numerous follow-on biologics for three classes of branded drugs. The results hint at what might be expected for U.S. firms: By 2008 in Germany, biosimilars had captured an estimated 14 percent to 30 percent market share and discounted prices by 25 percent [7]. The U.S. story of follow-on biologics will likely mirror that of EU biosimilars rather than that of small-molecule generics.With healthcare legislation passed and the inevitable refocusing on bending the cost curve in healthcare expenditures, big pharma firms may be able to boost their reputation with the public as well as their bottom line with a continued push into follow-on biologics. The decreased risk of approval and steady returns will help diversify pharmaceutical companies’ volatile revenue streams, while concurrently winning favorable public opinion by promoting price reductions for some of the most expensive drugs available. The cost savings to consumers will increase access for patients as FDA regulation is finalized and more and more follow-on biologics enter the market. This could be a win-win scenario for big pharma and for patients.     

The challenge of indication extrapolation for infliximab biosimilars

A biosimilar is intended to be highly similar to a reference biologic such that any differences in quality attributes (i.e., molecular characteristics) do not affect safety or efficacy. Achieving this benchmark for biologics, especially large glycoproteins such as monoclonal antibodies, is challenging given their complex structure and manufacturing. Regulatory guidance on biosimilars issued by the U.S. Food and Drug Administration, Health Canada and European Medicines Agency indicates that, in addition to a demonstration of a high degree of similarity in quality attributes, a reduced number of nonclinical and clinical comparative studies can be sufficient for approval. Following a tiered approach, clinical studies are required to address concerns about possible clinically significant differences that remain after laboratory and nonclinical evaluations. Consequently, a critical question arises: can clinical studies that satisfy concerns regarding safety and efficacy in one condition support “indication extrapolation” to other conditions? This question will be addressed by reviewing the case of a biosimilar to infliximab that was approved recently in South Korea, Europe, and Canada for multiple indications through extrapolation. The principles discussed should also apply to biosimilars of other monoclonal antibodies that are approved to treat multiple distinct conditions.     

Flash Glucose Monitoring: A Patient's and Clinician's Caveats and Concerns

Abbreviations: CGM = continuous glucose monitor; FDA = U.S. Food and Drug Administration; iCGM = intermittently scanned CGM; MBG = mean blood glucose; rtCGM = real-time CGM; T1D = type 1 diabetes     

American Association of Clinical Endocrinologists and American College of Endocrinology Position Statement on the Association of SGLT-2 Inhibitors and Diabetic Ketoacidosis

Abbreviations:AACE = American Association of Clinical EndocrinologistsACE = American College of EndocrinologyDKA = diabetic ketoacidosisEMA = European Medicines AgencyFDA = U.S. Food and Drug AdministrationSGLT-2 = sodium glucosecotransporter 2T1D = type 1 diabetesT2D = type 2 diabetes     

Historical and Current Perspective in the Use of Thyroid Extracts for the Treatment of Hypothyroidism

Objective: To describe the history, refinements, implementation, physiology, and clinical outcomes achieved over the past several centuries of thyroid hormone replacement strategies.Methods: A Medline search was initiated using the following search terms: bioidentical thyroid hormone, thyroid hormone extract, combination thyroxine (T4) and tri-iodothyronine (T3) therapy, homeopathic thyroid hormone therapy, and thyroid hormone replacement. Pertinent articles of interest were identified by title (and where available abstract) for further review. Additional references were identified during a review of the identified literature.Results: A rich history of physician intervention in thyroid dysfunction was identified dating back more than 2 millennia. Although not precisely documented, thyroid ingestion from animal sources had been used for centuries but was finally scientifically described and documented in Europe over 130 years ago. Since the reports by Bettencourt and Murray, there has been a continuous documentation of outcomes, refinement of hormone preparation production, and updating of recommendations for the most effective and safe use of these hormones for relieving the symptoms of hypothyroidism. As the thyroid extract preparations contain both levothyroxine (LT4) and liothyronine (LT3), current guidelines do not endorse their use as controlled studies do not clearly document enhanced objective outcomes compared with LT4 monotherapy. Among current issues cited, the optimum ratio of LT4 to LT3 has yet to be determined, and the U.S. Food and Drug Administration (FDA) does not appear to be monitoring the thyroid hormone ratios or content in extract preparations on the market. Taken together, these limitations are important detriments to the use of thyroid extract products.Conclusion: The evolution of thyroid hormone therapies has been significant over the extended period of time they have been in use to treat hypothyroidism. Although numerous websites continue to advocate the use of thyroid hormone extracts as a superior therapy for hypothyroidism, none of the most recent guidelines of major endocrine societies recommend thyroid extract use for hypothyroidism.Abbreviations: AACE = American Association of Clinical Endocrinologists ATA = American Thyroid Association BMR = basal metabolic rate FDA = Food and Drug Administration FT4 = free thyroxine 131-I = radioactive iodine 131 LT3 = liothyronine LT4= levothyroxine NDA = new drug application PBI = proteinbound iodine T3 = triiodothyronine T4 = thyroxine TSH = thyroid-stimulating hormone TT3 = total triiodothyronine USP = U.S. Pharmacopeia     

American Association of Clinical Endocrinologists and American College of Endocrinology Disease State Clinical Review: A Neuroendocrine Approach to Patients With Traumatic Brain Injury

Objective: Traumatic brain injury (TBI) is now recognized as a major public health concern in the United States and is associated with substantial morbidity and mortality in both children and adults. Several lines of evidence indicate that TBI-induced hypopituitarism is not infrequent in TBI survivors and may contribute to the burden of illness in this population. The goal of this article is to review the published data and propose an approach for the neuroendocrine evaluation and management of these patients.Methods: To identify pertinent articles, electronic literature searches were conducted using the following keywords: “traumatic brain injury,” “pituitary,” “hypopituitarism,” “growth hormone deficiency,” “hypogonadism,” “hypoadrenalism,” and “hypothyroidism.” Relevant articles were identified and considered for inclusion in the present article.Results: TBI-induced hypopituitarism appears to be more common in patients with severe TBI. However, patients with mild TBI or those with repeated, sports-, or blast-related TBI are also at risk for hypopituitarism. Deficiencies of growth hormone and gonadotropins appear to be most common and have been associated with increased morbidity in this population. A systematic approach is advised in order to establish the presence of pituitary hormone deficiencies and implement appropriate replacement therapies.Conclusion: The presence of traumatic hypopituitarism should be considered during the acute phase as well as during the rehabilitation phase of patients with TBI. All patients with moderate to severe TBI require evaluation of pituitary function. In addition, symptomatic patients with mild TBI and impaired quality of life are at risk for hypopituitarism and should be offered neuroendocrine testing.Abbreviations: CBG = corticosteroid-binding globulin DI = diabetes insipidus GH = growth hormone IGF-1 = insulin-like growth factor 1 SIADH = syndrome of inappropriate antidiuretic hormone T₄ = thyroxine TBI = traumatic brain injury TSH = thyroid-stimulating hormone     

Clinical considerations for the development of biosimilars in oncology

Despite availability of biologic therapies, limited patient access to many of the most-effective cancer treatments affects overall health outcomes. To address this issue, many governments have enacted legislation for the approval of biosimilars. The term “biosimilar” refers to a biologic product that is developed to be highly similar, as opposed to identical, to a licensed biologic product (the reference or innovator product), such that, per US Food and Drug administration draft guidelines, “no clinically meaningful differences [exist] between the biological product and the reference product in terms of safety, purity, and potency.” This article presents some considerations about the development of biosimilars in cancer treatment through an overview of biosimilars from a clinical perspective. Topics covered include the development requirements and unique regulatory requirements for biosimilars, labeling considerations, potential limitations to the uptake of biosimilars, and review of some biosimilars in development for oncology indications.     

Integrated Insulin Pump and Continuous Glucose Monitoring Technology in Diabetes Care Today: A Perspective of Real-Life Experience With the Minimed™ 670G Hybrid Closed-Loop System

Objective: Intensive glucose management with insulin pump and continuous glucose monitoring therapy in insulin-treated patients with diabetes poses many challenges in all aspects of daily life. Automated insulin delivery (AID) is the ultimate goal of insulin replacement therapy to reduce the burden of managing this condition. Many systems are being tested in the clinical research setting, and one hybrid closed-loop (HCL) system has received Food and Drug Administration (FDA) approval for use in type 1 diabetes patients above the age of 14 years.Methods: Literature review and clinical practice experience from the Diabetes and Technology Program at an academic medical center.Results: This review outlines recent advances in AID systems, focusing on the FDA-approved MiniMed™ 670G HCL system and the real-life experience 1-year post-release in an academic medical center with over 60 patients on this system. The unique challenges of adapting to this new system outside the clinical trial setting are highlighted, and a training protocol designed specifically for the onboarding of first-time users is described.Conclusion: HCL insulin therapy offers several advantages, at the same time posing unique challenges to the user. Systematic training of patients with diabetes transitioning to this system is essential for retention and success of use.Abbreviations: AID = automated insulin delivery; CGM = continuous glucose monitoring; FDA = Food and Drug Administration; HbA1c = glycated hemoglobin; HCL = hybrid closed-loop; ICR = insulin to carbohydrate ratio; SAP = sensor augmented pump; T1DM = type 1 diabetes     

Biosimilars in oncology and inflammatory diseases: current and future considerations for clinicians in Latin America

Biological therapies have revolutionized the treatment of several cancers and systemic immune-mediated inflammatory conditions. Expiry of patents protecting a number of biologics has provided the opportunity to commercialize highly similar versions, known as biosimilars. Biosimilars are approved by regulatory agencies via an independent pathway that requires extensive head-to-head comparison with the originator product. Biosimilars have the potential to provide savings to healthcare systems and expand patient access to biologics. In Latin American countries, regulatory frameworks for biosimilar approval have been introduced in recent years, and biosimilars of monoclonal antibody and fusion protein therapies are now emerging. However, the situation in this region is complicated by the presence of “non-comparable biotherapeutics” (also known as “intended copies”), which have not been rigorously compared with the originator product. We review the considerations for clinicians in Latin American countries, focusing on monoclonal antibody biosimilars relevant to oncology, rheumatology, gastroenterology, and dermatology.     

Biosimilars: a regulatory perspective from America

Biosimilars are protein products that are sufficiently similar to a biopharmaceutical already approved by a regulatory agency. Several biotechnology companies and generic drug manufacturers in Asia and Europe are developing biosimilars of tumor necrosis factor inhibitors and rituximab. A biosimilar etanercept is already being marketed in Colombia and China. In the US, several natural source products and recombinant proteins have been approved as generic drugs under Section 505(b)(2) of the Food, Drug, and Cosmetic Act. However, because the complexity of large biopharmaceuticals makes it difficult to demonstrate that a biosimilar is structurally identical to an already approved biopharmaceutical, this Act does not apply to biosimilars of large biopharmaceuticals. Section 7002 of the Patient Protection and Affordable Care Act of 2010, which is referred to as the Biologics Price Competition and Innovation Act of 2009, amends Section 351 of the Public Health Service Act to create an abbreviated pathway that permits a biosimilar to be evaluated by comparing it with only a single reference biological product. This paper reviews the processes for approval of biosimilars in the US and the European Union and highlights recent changes in federal regulations governing the approval of biosimilars in the US.     

Endocrine Complications in Patients with Gvhd

Objective: Graft-versus-host disease (GVHD) is an immune phenomenon that occurs in 30 to 70% of patients after allogeneic hematopoietic stem cell transplantation (HST). Chronic GVHD is a state of immune dysregulation wherein, depending on the severity and organ involved, patients may require prolonged treatment with additional or higher corticosteroids and other immunosuppressive agents. The objective of this study was to review the endocrine manifestations following HST that can arise as a consequence of the primary disease or its treatment, including chemotherapeutic agents, corticosteroids, radiation, or GVHD.Methods: We performed a narrative review of GVHD after HST. An English-language search for relevant studies was conducted on PubMed from inception to August 1, 2018, using the following search terms: “endocrine complications,” “bone marrow transplantation,” “graft-versus-host disease,” and “GVHD.” The reference lists of relevant studies were also reviewed.Results: Chronic GVHD may be associated with considerable pediatric growth impairment and may also contribute to thyroid gland dysfunction and thyroid cancer. These patients may also be at increased risk for low bone mineral density, reduced fertility, metabolic syndrome, and suppression of the pituitary-adrenal axis with adrenal insufficiency.Conclusion: This review indicates the importance of monitoring, diagnosing, and properly treating the endocrine complications in this population. More studies are needed to investigate the independent impact of GVHD on the endocrine system and treatment for complications.Abbreviations: BMD = bone mineral density; GH = growth hormone; GVHD = graft-versus-host disease; HST = hematopoietic stem cell transplantation; IGF-1 = insulin-like growth factor 1     

Use of Metformin in Clinical Endocrinology

Abbreviations:CKD = chronic kidney diseaseDM = diabetes mellituseGFR = estimated glomerular filtration rateFDA = Food & Drug Administration     

Potential Place of SGLT2 Inhibitors in Treatment Paradigms for type 2 Diabetes Mellitus

Objective: Following the first Food and Drug Administration (FDA) approval in 2013, sodium glucose cotransporter 2 (SGLT2) inhibitors have generated much interest among physicians treating patients with type 2 diabetes mellitus (T2DM). Here, the role in treatment with this drug class is considered in the context of T2DM treatment paradigms.Methods: The clinical trials for the SGLT2 inhibitors are examined with a focus on canagliflozin, dapagliflozin, and empagliflozin.Results: Evidence from clinical trials in patients with T2DM supports the use of SGLT2 inhibitors either as monotherapy or in addition to other glucose-lowering treatments as adjuncts to diet and exercise, and we have gained significant clinical experience in a relatively short time.Conclusion: The drugs appear to be useful in a variety of T2DM populations, contingent primarily on renal function. Most obviously, SGLT2 inhibitors appear to be well suited for patients with potential for hypoglycemia or weight gain. In clinical trials, patients treated with SGLT2 inhibitors have experienced moderate weight loss and a low risk of hypoglycemic events except when used in combination with an insulin secretagogue. In addition, SGLT2 inhibitors have been shown to reduce blood pressure, so they may be beneficial in patients with T2DM complicated by hypertension. SGLT2 inhibitors were incorporated into the 2015 American Diabetes Association (ADA)/European Association for the Study of Diabetes (EASD) position statement on the management of hyperglycemia and received an even more prominent position in the American Association of Clinical Endocrinologists (AACE)/American College of Endocrinology (ACE) comprehensive diabetes management guidelines and algorithm.Abbreviations: AE = adverse event A1C = glycated hemoglobin CI = confidence interval CKD = chronic kidney disease DKA = diabetic ketoacidosis DPP-4 = dipeptidyl peptidase 4 eGFR = estimated glomerular filtration rate FDA = Food and Drug Administration FPG = fasting plasma glucose GLP-1 = glucagon-like peptide 1 HDL-C = high-density lipoprotein cholesterol HR = hazard ratio LADA = late-onset autoimmune diabetes of adulthood LDL-C = low-density lipoprotein cholesterol MACE = major adverse cardiovascular events SGLT1 = sodium glucose cotransporter 1 SGLT2 = sodium glucose cotransporter 2 T1DM = type 1 diabetes mellitus T2DM = type 2 diabetes mellitus UACR = urine albumin to creatinine ratio     

Adipsic Diabetes Insipidus: A Review

Objective: Adipsic diabetes insipidus (ADI) is a rare disorder consisting of central diabetes insipidus (CDI) and a deficient or absent thirst response to hyperosmolality. Patients with ADI experience marked morbidity and mortality. Diagnosis and management of these patients is quite challenging, even in expert hands. In this review, we aim to provide an updated overview of this difficult clinical scenario.Methods: We conducted a PubMed search for articles related to ADI. The search terms “adipsia,” “adipsic,” “thirst,” and “diabetes insipidus” were used to identify relevant literature.Results: ADI has been described in only approximately 100 patients. This rarity has limited the quality and quantity of literature to case reports, case series, and expert opinion. Diagnosis focuses on confirmation of CDI followed by documenting subnormal or completely absent thirst in response to a hypertonic stimulus. Among the described patients with ADI, the majority experience morbidity (e.g., severe hypernatremia, sleep apnea, venous thromboembolism [VTE], and obesity) and an increased mortality risk. Management focuses on frequent reassessment of daily prescribed water intake with fixed antidiuretic therapy (desmopressin) and comorbidity screening.Conclusion: The complexity of patients with ADI provides a difficult challenge for clinicians. Prompt recognition of thirst disorders in patients with CDI should lead to appropriately regimented management strategies and can result in safe outpatient care for these unique patients.Abbreviations:ACoA = anterior communicating arteryADI = adipsic diabetes insipidusAVP = arginine vasopressinCDI = central diabetes insipidusDDAVP = desmopressinDI = diabetes insipidusSDB = sleep-disordered breathingVTE = venous thromboembolism