The costs and benefits of SGLT2 inhibitors & GLP-1 RAs

The options for treating type 2 diabetes without insulin have grown beyond metformin to include a long list of sodium-glucose cotransporter 2 (SGLT2) inhibitors and glucagonlike peptide–1 (GLP-1) receptor agonists that can be taken with or without metformin. These new drugs have cardiovascular and kidney benefits and help with weight loss, but they also carry risks and, according to some experts, their costs can be prohibitively expensive.
 

Given the medical community’s long-term experience with treating patients with metformin, and metformin’s lower cost, most of the physicians interviewed for this article advise using SGLT2 inhibitors and GLP-1 receptor agonists as second-line treatments. Others said that they would prefer to use the newer drugs as first-line therapies in select high-risk patients, but prior authorization hurdles created by insurance companies make that approach too burdensome.

“The economics of U.S. health care is stacked against many of our patients with diabetes in the current era,” Robert H. Hopkins Jr., MD, said in an interview.

Even when their insurance approves the drugs, patients still may not be able to afford the copay, explained Dr. Hopkins, professor of internal medicine and pediatrics and director of the division of general internal medicine at the University of Arkansas for Medical Sciences, Little Rock. “Sometimes patients can purchase drugs at a lower cost than the copay to purchase with the ‘drug coverage’ in their insurance plan – unfortunately, this is not the case with the newer diabetes medications we are discussing here.”

“SGLT2 inhibitors and GLP-1 agonists can cost several hundred dollars a month, and insurers often balk at paying for them. They’ll say, ‘Have you tried metformin?’ ” explained endocrinologist Victor Lawrence Roberts, MD, in a interview. “We have to work with insurance companies the best we can in a stepwise fashion.”

According to Dr. Roberts, 80% of his patients with diabetes struggle with the cost of medicine in general. “They’re either underinsured or not insured or their formulary is limited.

Douglas S. Paauw, MD, agreed in an interview that the newer drugs can be problematic on the insurance front.

“For some patients they aren’t affordable, especially for the uninsured if you can’t get them on an assistance program,” said Dr. Paauw, who is professor of medicine in the division of general internal medicine at the University of Washington, Seattle, and serves as third-year medical student clerkship director at the university.

Dr. Hopkins, who is on the Internal Medicine News board, noted that “unfortunately, the treatment of type 2 diabetes in patients who cannot achieve control with metformin, diet, weight control, and exercise is a story of the ‘haves’ and the ‘have nots.’ The ‘haves’ are those who have pharmacy benefits which make access to newer agents like SGLT2 inhibitors and GLP-1 agonists a possibility.”

“I have had very few of the ‘have nots’ who have been able to even consider these newer agents, which carry price tags of $600-$1,300 a month even with the availability of discounting coupons in the marketplace,” he added. “Most of these patients end up requiring a sulfonylurea or TZD [thiazolidinedione] as a second agent to achieve glycemic control. This makes it very difficult to achieve sufficient weight and metabolic control to avoid an eventual switch to insulin.”

Fatima Z. Syed, MD, an endocrine-trained general internist at DukeHealth in Durham, N.C., said she prescribes SGLT2 inhibitors and GLP-1 receptor agonists in combination with metformin. “I prescribe them frequently, but they are not first-line treatments,” she explained.

“Nothing replaces diet and exercise” as therapy for patients with type 2 diabetes, she added.

Neil S. Skolnik, MD, said that insurance companies were not preventing patients from using these drugs in his experience. He also provided an optimistic take on the accessibility of these drugs in the near future.

“Most insurance companies are now covering select SGLT2 inhibitors and GLP-1 receptor agonists for appropriate patients and those companies that currently do not will soon have to,” said Dr. Skolnik, who is a professor of family and community medicine at Jefferson Medical College, Philadelphia, and an associate director of the family medicine residency program at Abington (Pa.) Jefferson Health.

“The outcomes [associated with use of the new drugs] are robust, the benefits are large, and are well worth the cost,” he added.
 

 

The side effects

While others praised these drugs for their beneficial effects, they also noted that the side effects of these drugs are serious and must be discussed with patients.

GLP-1 receptor agonists are linked to gastrointestinal symptoms, especially nausea, while SGLT2 inhibitors have been linked to kidney failure, ketoacidosis, and more. The Food and Drug Administration warned in 2018 that the SGLT2 inhibitors can cause a rare serious infection known as Fournier’s gangrene – necrotizing fasciitis of the perineum.

“We have to tell our patients to let us know right away if they get pain or swelling in the genital area,” Dr. Paauw, who is on the Internal Medicine News board, noted. “The chance that an infection could explode quickly is higher in those who take these drugs.”

Amputation risks also are associated with taking the SGLT2 inhibitor canagliflozin (Invokana). The FDA requires the manufacturer of this drug to include a black-box warning about the risk of “lower-limb amputations, most frequently of the toe and midfoot,” but also the leg. In approval trials, the risk doubled versus placebo.

These amputation risks “put a damper on some of the enthusiasm on behalf of physicians and patients ... for taking this drug,” noted Dr. Roberts, who is a professor of internal medicine at the University of Central Florida, Orlando.

While a manufacturer-funded study released last year found no link to amputations, the results weren’t powerful enough to rule out a moderately increased risk.

“[If] you are at high risk for having an amputation, we really have to take this risk very seriously,” said John B. Buse, MD, chief of the division of endocrinology at the University of North Carolina at Chapel Hill, in a presentation about the study at the 2018 annual scientific sessions of the American Diabetes Association.
 

The benefits

Despite these risks of adverse events, most interviewed agreed that the many benefits observed in those taking SGLT2 inhibitors or GLP-1 receptor agonists make them worth prescribing, at least to those who are able to afford them.

Both SGLT2 inhibitors and GLP-1 receptor agonists appear to have significant cardiovascular benefits. A 2019 meta-­analysis and systematic review found that both drugs reduced major adverse cardiac events by about 12% (Circulation. 2019 Apr 23;139[17]:2022-31).

“They don’t cause hypoglycemia, they lower blood pressure, they don’t cause weight gain, and they might promote weight loss,” noted Dr. Paauw.

SGLT2 inhibitors also have shown signs of kidney benefits. The CREDENCE trial linked canagliflozin to a lowering of kidney disorders versus placebo (N Engl J Med. 2019 Jun 13;380[24]:2295-306). “The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% confidence interval, 0.53-0.81; P less than .001), and the relative risk of end-stage kidney disease was lower by 32% (HR, 0.68; 95% CI, 0.54-0.86; P = .002),” the trial investigators wrote.

“They showed very nicely that the drug improved the kidney function of those patients and reduced the kidney deterioration,” said Yehuda Handelsman, MD, an endocrinologist in Tarzana, Calif., who chaired the 2011 and 2015 American Association of Clinical Endocrinologists’ Comprehensive Diabetes Guidelines. The study was especially impressive, he added, because it included patients with low kidney function.

SGLT2 inhibitors’ “diuretic mechanism explains why there is a substantial reduction in heart failure hospitalizations in patients who take these drugs,” said cardiologist Marc E. Goldschmidt, MD, director of the Heart Success Program at Atlantic Health System’s Morristown (N.J.) Medical Center, in an interview. “Both the EMPA-REG Outcome and the CREDENCE trials demonstrated substantial benefit of this class of medications by showing a lower risk of cardiovascular death as well as death from any cause and a lower risk of hospitalization for heart failure."

Overall, the SGLT2 trial data have been very consistent with a benefit for cardiovascular risk reduction, particularly in regard to heart failure hospitalizations and even in potentially preventing heart failure in diabetics,” he added.

Dr. Skolnik, a columnist for Family Practice News, cited SGLT2 inhibitors and GLP-1 receptor agonists’ ability to slow renal disease progression, promote weight loss, and prevent poor cardiac outcomes.“These drugs should be used, in addition to metformin, in all patients with diabetes and vascular disease. These proven outcomes are far better than we ever were able to achieve previously and the strength of the evidence at this point is very strong,” said Dr. Skolnik. “In addition to the benefits of decreasing the development of cardiovascular disease, serious heart failure, and slowing progression of renal disease, these two classes of medication have additional benefits. Both classes help patients lose weight, which is very different from what was found with either sulfonylureas or insulin, which cause patients to gain weight. Also both the SGLT2 inhibitors and the GLP-1 RAs [receptor agonists] have a low incidence of hypoglycemia. For all these reasons, these have become important medications for us to use in primary care.”

Other recent trials offer “very powerful data” about SGLT2 inhibitors, Dr. Roberts said. That’s good news, since “our approach needs to be toward cardiovascular protection and preservation as well as managing blood sugar.”An Israeli trial, whose results were released in May 2019 at the annual meeting of the American College of Cardiology, found that, compared with other glucose-lowering drugs, taking an SGLT2 inhibitor was associated with lower risks of heart failure hospitalization and all-cause mortality (HR, 0.54; 95% CI, 0.44-0.65; P less than .001). This trial also offered a new detail: The patients gained the benefit regardless of whether their baseline left ventricular ejection fraction was preserved or reduced (J Coll Cardiol. 2019 Mar;73[9]:suppl 1). The SGLT2 inhibitors used in this trial included dapagliflozin (Farxiga) and empagliflozin (Jardiance).

In another study released this year, a subanalysis of the DECLARE-TIMI 58 trial, researchers reported that the SGLT2 inhibitor dapagliflozin reduced risks of both major adverse cardiovascular events and heart failure hospitalization in the subset of patients with type 2 diabetes and prior myocardial infarction versus controls (Circulation. 2019 May 28;139[22]:2516-27). The absolute risk reduction for major adverse cardiovascular events was 1.9% (HR, 0.81; 95% CI, 0.65-1.00; P = .046), while it was 0.6% for heart failure hospitalization (HR, 0.85; 95% CI, 0.72-1.00; P = .055).

These and other studies “speak volumes about the efficacy of managing blood sugar and addressing our biggest nemesis, which is cardiovascular disease,” Dr. Roberts said. “It’s irrefutable. The data [are] very good.”

Dr. Paauw said an SGLT2 inhibitor or GLP-1 receptor agonist is best reserved for use in select patients with cardiovascular risks and type 2 diabetes that need management beyond metformin.

For example, they might fit a 70-year-old with persistent hypertension who’s already taking a couple of blood pressure medications. “If they have another cardiovascular risk factor, the cardiovascular protection piece will be a bigger deal,” he said. Also, “it will probably help lower their blood pressure so they can avoid taking another blood pressure medicine.”

Trials of both GLP-1 receptor agonists and SGLT2 inhibitors have shown benefits “in improving [major adverse cardiac events], with the SGLT2 class showing substantial benefit in improving both heart failure and renal outcomes as well,” noted Dr. Skolnik. “It is in this context that one must address the question of whether the price of the medications are worthwhile. With such substantial benefit, there is no question in my mind that – for patients who have underlying cardiovascular illness, which includes patients with existent coronary disease, history of stroke, transient ischemic attack, or peripheral vascular disease – it is far and away worth it to prescribe these classes of medications.”

Indeed, the American Diabetes Association and the European Association for the Study of Diabetes’ most recent guidelines now call for a GLP-1 receptor agonist – instead of insulin – to be the first injectable used to treat type 2 diabetes (Diabetes Care 2018 Dec; 41[12]:2669-701).

“For the relatively small number of my patients who have been able to access and use these medications for months or longer, more have tolerated the GLP-1 agonists than SGLT2 inhibitors primarily due to urinary issues,” noted Dr. Hopkins.

Dipeptidyl peptidase–4 inhibitors are another option in patients with type 2 diabetes, but research suggests they may not be a top option for patients with cardiovascular risk. A 2018 review noted that cardiovascular outcome trials for alogliptin (Nesina), saxagliptin (Onglyza), and sitagliptin (Januvia) showed noninferiority but failed to demonstrate any superiority, compared with placebo in patients with type 2 diabetes mellitus and high cardiovascular risk (Circ Res. 2018 May 11;122[10]:1439-59).
 

 

The combination therapies

Many of the newer drugs are available as combinations with other types of diabetes drugs. In some cases, physicians create their own form of combination therapy by separately prescribing two or more diabetes drugs. Earlier this year, a study suggested the benefits of this kind of add-on therapy: Diabetes outcomes improved in patients who took the GLP-1 receptor agonist semaglutide and an SGLT2 inhibitor (Lancet Diabetes Endocrinol. 2019 Mar 1. doi: 10.1016/S2213-8587[19]30066-X).

 

Dr. Roberts suggested caution, however, when prescribing combination therapies. “My recommendation is always to begin with the individual medications to see if the patient tolerates the drugs and then decide which component needs to be titrated. It’s hard to titrate a combination drug, and it doesn’t leave a lot of flexibility. You never know which drug is doing what.
 

Dr. Handelsman said some patients may need to take three medications such as metformin, an SGLT2 inhibitor, and a GLP-1 receptor agonist.

“I don’t recommend using the combinations if you’re not familiar with the drugs ... These are relatively new pharmaceuticals, and most of us are on a learning curve as to how they fit into the armamentarium. If a drug is tolerated with a good response, you can certainly consider going to the combination tablets,” he added.

There is at least one drug that combines these three classes: The newly FDA-approved Qternmet XR, which combines dapagliflozin (an SGLT2 inhibitor), saxagliptin (a GLP-1 receptor agonist), and metformin. As of mid-June 2019, it was not yet available in the United States. Its sister drug Qtern, which combines dapagliflozin and saxagliptin, costs more than $500 a month with a free coupon, according to goodrx.com. In contrast, metformin is extremely inexpensive, costing just a few dollars a month for a common starting dose.
 

What about adding insulin?

“Both [SGLT2 inhibitors and GLP-1 receptor agonists] work very well with insulin,” Dr. Handelsman said. “There is a nice additive effect on the reduction of [hemoglobin] A_1c. The only caution is that, although neither SGLT2 inhibitors nor GLP-1 receptor agonists cause hypoglycemia, in combination with insulin they do increase the risk of hypoglycemia. You may have to adjust the dose of insulin.”

Dr. Hopkins warned that cost becomes an even bigger issue when you add insulin into the mix.

“When insulin comes into the discussion, we are again stuck with astronomical costs which many struggle to afford,” he explained.

Indeed, the price tag on these drugs seems to be the biggest problem physicians have with them.

“The challenges in managing patients with diabetes aren’t the risks associated with the drugs. It’s dealing with their insurers,” noted Dr. Roberts.

Dr. Hopkins, Dr. Paauw, Dr. Roberts, and Dr. Syed reported no disclosures. Dr. Buse is an investigator for Johnson and Johnson. Dr. Goldschmidt is paid to speak by Novartis. Dr. Handelsman reported research grants, consulting work, and speaker honoraria from Amgen, Gilead, Lilly, Merck, Novo Nordisk, and others. Dr Skolnik reported nonfinancial support from AstraZeneca, Boehringer Ingelheim, Sanofi, and GlaxoSmithKline and personal fees from AstraZeneca, Boehringer Ingelheim, and Eli Lilly. He also serves on the advisory boards of AstraZeneca, Boehringer Ingelheim, Teva Pharmaceutical, Eli Lilly, Sanofi, Janssen Pharmaceuticals, Intarcia, Mylan, and GlaxoSmithKline.

Dr. Paauw and Dr. Skolnik are columnists for Family Practice News and Internal Medicine News.

M. Alexander Otto contributed to this report.

klennon@mdedge.com

The options for treating type 2 diabetes without insulin have grown beyond metformin to include a long list of sodium-glucose cotransporter 2 (SGLT2) inhibitors and glucagonlike peptide–1 (GLP-1) receptor agonists that can be taken with or without metformin. These new drugs have cardiovascular and kidney benefits and help with weight loss, but they also carry risks and, according to some experts, their costs can be prohibitively expensive.
 

Given the medical community’s long-term experience with treating patients with metformin, and metformin’s lower cost, most of the physicians interviewed for this article advise using SGLT2 inhibitors and GLP-1 receptor agonists as second-line treatments. Others said that they would prefer to use the newer drugs as first-line therapies in select high-risk patients, but prior authorization hurdles created by insurance companies make that approach too burdensome.

“The economics of U.S. health care is stacked against many of our patients with diabetes in the current era,” Robert H. Hopkins Jr., MD, said in an interview.

Even when their insurance approves the drugs, patients still may not be able to afford the copay, explained Dr. Hopkins, professor of internal medicine and pediatrics and director of the division of general internal medicine at the University of Arkansas for Medical Sciences, Little Rock. “Sometimes patients can purchase drugs at a lower cost than the copay to purchase with the ‘drug coverage’ in their insurance plan – unfortunately, this is not the case with the newer diabetes medications we are discussing here.”

“SGLT2 inhibitors and GLP-1 agonists can cost several hundred dollars a month, and insurers often balk at paying for them. They’ll say, ‘Have you tried metformin?’ ” explained endocrinologist Victor Lawrence Roberts, MD, in a interview. “We have to work with insurance companies the best we can in a stepwise fashion.”

According to Dr. Roberts, 80% of his patients with diabetes struggle with the cost of medicine in general. “They’re either underinsured or not insured or their formulary is limited.

Douglas S. Paauw, MD, agreed in an interview that the newer drugs can be problematic on the insurance front.

“For some patients they aren’t affordable, especially for the uninsured if you can’t get them on an assistance program,” said Dr. Paauw, who is professor of medicine in the division of general internal medicine at the University of Washington, Seattle, and serves as third-year medical student clerkship director at the university.

Dr. Hopkins, who is on the Internal Medicine News board, noted that “unfortunately, the treatment of type 2 diabetes in patients who cannot achieve control with metformin, diet, weight control, and exercise is a story of the ‘haves’ and the ‘have nots.’ The ‘haves’ are those who have pharmacy benefits which make access to newer agents like SGLT2 inhibitors and GLP-1 agonists a possibility.”

“I have had very few of the ‘have nots’ who have been able to even consider these newer agents, which carry price tags of $600-$1,300 a month even with the availability of discounting coupons in the marketplace,” he added. “Most of these patients end up requiring a sulfonylurea or TZD [thiazolidinedione] as a second agent to achieve glycemic control. This makes it very difficult to achieve sufficient weight and metabolic control to avoid an eventual switch to insulin.”

Fatima Z. Syed, MD, an endocrine-trained general internist at DukeHealth in Durham, N.C., said she prescribes SGLT2 inhibitors and GLP-1 receptor agonists in combination with metformin. “I prescribe them frequently, but they are not first-line treatments,” she explained.

“Nothing replaces diet and exercise” as therapy for patients with type 2 diabetes, she added.

Neil S. Skolnik, MD, said that insurance companies were not preventing patients from using these drugs in his experience. He also provided an optimistic take on the accessibility of these drugs in the near future.

“Most insurance companies are now covering select SGLT2 inhibitors and GLP-1 receptor agonists for appropriate patients and those companies that currently do not will soon have to,” said Dr. Skolnik, who is a professor of family and community medicine at Jefferson Medical College, Philadelphia, and an associate director of the family medicine residency program at Abington (Pa.) Jefferson Health.

“The outcomes [associated with use of the new drugs] are robust, the benefits are large, and are well worth the cost,” he added.
 

 

The side effects

While others praised these drugs for their beneficial effects, they also noted that the side effects of these drugs are serious and must be discussed with patients.

GLP-1 receptor agonists are linked to gastrointestinal symptoms, especially nausea, while SGLT2 inhibitors have been linked to kidney failure, ketoacidosis, and more. The Food and Drug Administration warned in 2018 that the SGLT2 inhibitors can cause a rare serious infection known as Fournier’s gangrene – necrotizing fasciitis of the perineum.

“We have to tell our patients to let us know right away if they get pain or swelling in the genital area,” Dr. Paauw, who is on the Internal Medicine News board, noted. “The chance that an infection could explode quickly is higher in those who take these drugs.”

Amputation risks also are associated with taking the SGLT2 inhibitor canagliflozin (Invokana). The FDA requires the manufacturer of this drug to include a black-box warning about the risk of “lower-limb amputations, most frequently of the toe and midfoot,” but also the leg. In approval trials, the risk doubled versus placebo.

These amputation risks “put a damper on some of the enthusiasm on behalf of physicians and patients ... for taking this drug,” noted Dr. Roberts, who is a professor of internal medicine at the University of Central Florida, Orlando.

While a manufacturer-funded study released last year found no link to amputations, the results weren’t powerful enough to rule out a moderately increased risk.

“[If] you are at high risk for having an amputation, we really have to take this risk very seriously,” said John B. Buse, MD, chief of the division of endocrinology at the University of North Carolina at Chapel Hill, in a presentation about the study at the 2018 annual scientific sessions of the American Diabetes Association.
 

The benefits

Despite these risks of adverse events, most interviewed agreed that the many benefits observed in those taking SGLT2 inhibitors or GLP-1 receptor agonists make them worth prescribing, at least to those who are able to afford them.

Both SGLT2 inhibitors and GLP-1 receptor agonists appear to have significant cardiovascular benefits. A 2019 meta-­analysis and systematic review found that both drugs reduced major adverse cardiac events by about 12% (Circulation. 2019 Apr 23;139[17]:2022-31).

“They don’t cause hypoglycemia, they lower blood pressure, they don’t cause weight gain, and they might promote weight loss,” noted Dr. Paauw.

SGLT2 inhibitors also have shown signs of kidney benefits. The CREDENCE trial linked canagliflozin to a lowering of kidney disorders versus placebo (N Engl J Med. 2019 Jun 13;380[24]:2295-306). “The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% confidence interval, 0.53-0.81; P less than .001), and the relative risk of end-stage kidney disease was lower by 32% (HR, 0.68; 95% CI, 0.54-0.86; P = .002),” the trial investigators wrote.

“They showed very nicely that the drug improved the kidney function of those patients and reduced the kidney deterioration,” said Yehuda Handelsman, MD, an endocrinologist in Tarzana, Calif., who chaired the 2011 and 2015 American Association of Clinical Endocrinologists’ Comprehensive Diabetes Guidelines. The study was especially impressive, he added, because it included patients with low kidney function.

SGLT2 inhibitors’ “diuretic mechanism explains why there is a substantial reduction in heart failure hospitalizations in patients who take these drugs,” said cardiologist Marc E. Goldschmidt, MD, director of the Heart Success Program at Atlantic Health System’s Morristown (N.J.) Medical Center, in an interview. “Both the EMPA-REG Outcome and the CREDENCE trials demonstrated substantial benefit of this class of medications by showing a lower risk of cardiovascular death as well as death from any cause and a lower risk of hospitalization for heart failure."

Overall, the SGLT2 trial data have been very consistent with a benefit for cardiovascular risk reduction, particularly in regard to heart failure hospitalizations and even in potentially preventing heart failure in diabetics,” he added.

Dr. Skolnik, a columnist for Family Practice News, cited SGLT2 inhibitors and GLP-1 receptor agonists’ ability to slow renal disease progression, promote weight loss, and prevent poor cardiac outcomes.“These drugs should be used, in addition to metformin, in all patients with diabetes and vascular disease. These proven outcomes are far better than we ever were able to achieve previously and the strength of the evidence at this point is very strong,” said Dr. Skolnik. “In addition to the benefits of decreasing the development of cardiovascular disease, serious heart failure, and slowing progression of renal disease, these two classes of medication have additional benefits. Both classes help patients lose weight, which is very different from what was found with either sulfonylureas or insulin, which cause patients to gain weight. Also both the SGLT2 inhibitors and the GLP-1 RAs [receptor agonists] have a low incidence of hypoglycemia. For all these reasons, these have become important medications for us to use in primary care.”

Other recent trials offer “very powerful data” about SGLT2 inhibitors, Dr. Roberts said. That’s good news, since “our approach needs to be toward cardiovascular protection and preservation as well as managing blood sugar.”An Israeli trial, whose results were released in May 2019 at the annual meeting of the American College of Cardiology, found that, compared with other glucose-lowering drugs, taking an SGLT2 inhibitor was associated with lower risks of heart failure hospitalization and all-cause mortality (HR, 0.54; 95% CI, 0.44-0.65; P less than .001). This trial also offered a new detail: The patients gained the benefit regardless of whether their baseline left ventricular ejection fraction was preserved or reduced (J Coll Cardiol. 2019 Mar;73[9]:suppl 1). The SGLT2 inhibitors used in this trial included dapagliflozin (Farxiga) and empagliflozin (Jardiance).

In another study released this year, a subanalysis of the DECLARE-TIMI 58 trial, researchers reported that the SGLT2 inhibitor dapagliflozin reduced risks of both major adverse cardiovascular events and heart failure hospitalization in the subset of patients with type 2 diabetes and prior myocardial infarction versus controls (Circulation. 2019 May 28;139[22]:2516-27). The absolute risk reduction for major adverse cardiovascular events was 1.9% (HR, 0.81; 95% CI, 0.65-1.00; P = .046), while it was 0.6% for heart failure hospitalization (HR, 0.85; 95% CI, 0.72-1.00; P = .055).

These and other studies “speak volumes about the efficacy of managing blood sugar and addressing our biggest nemesis, which is cardiovascular disease,” Dr. Roberts said. “It’s irrefutable. The data [are] very good.”

Dr. Paauw said an SGLT2 inhibitor or GLP-1 receptor agonist is best reserved for use in select patients with cardiovascular risks and type 2 diabetes that need management beyond metformin.

For example, they might fit a 70-year-old with persistent hypertension who’s already taking a couple of blood pressure medications. “If they have another cardiovascular risk factor, the cardiovascular protection piece will be a bigger deal,” he said. Also, “it will probably help lower their blood pressure so they can avoid taking another blood pressure medicine.”

Trials of both GLP-1 receptor agonists and SGLT2 inhibitors have shown benefits “in improving [major adverse cardiac events], with the SGLT2 class showing substantial benefit in improving both heart failure and renal outcomes as well,” noted Dr. Skolnik. “It is in this context that one must address the question of whether the price of the medications are worthwhile. With such substantial benefit, there is no question in my mind that – for patients who have underlying cardiovascular illness, which includes patients with existent coronary disease, history of stroke, transient ischemic attack, or peripheral vascular disease – it is far and away worth it to prescribe these classes of medications.”

Indeed, the American Diabetes Association and the European Association for the Study of Diabetes’ most recent guidelines now call for a GLP-1 receptor agonist – instead of insulin – to be the first injectable used to treat type 2 diabetes (Diabetes Care 2018 Dec; 41[12]:2669-701).

“For the relatively small number of my patients who have been able to access and use these medications for months or longer, more have tolerated the GLP-1 agonists than SGLT2 inhibitors primarily due to urinary issues,” noted Dr. Hopkins.

Dipeptidyl peptidase–4 inhibitors are another option in patients with type 2 diabetes, but research suggests they may not be a top option for patients with cardiovascular risk. A 2018 review noted that cardiovascular outcome trials for alogliptin (Nesina), saxagliptin (Onglyza), and sitagliptin (Januvia) showed noninferiority but failed to demonstrate any superiority, compared with placebo in patients with type 2 diabetes mellitus and high cardiovascular risk (Circ Res. 2018 May 11;122[10]:1439-59).
 

 

The combination therapies

Many of the newer drugs are available as combinations with other types of diabetes drugs. In some cases, physicians create their own form of combination therapy by separately prescribing two or more diabetes drugs. Earlier this year, a study suggested the benefits of this kind of add-on therapy: Diabetes outcomes improved in patients who took the GLP-1 receptor agonist semaglutide and an SGLT2 inhibitor (Lancet Diabetes Endocrinol. 2019 Mar 1. doi: 10.1016/S2213-8587[19]30066-X).

 

Dr. Roberts suggested caution, however, when prescribing combination therapies. “My recommendation is always to begin with the individual medications to see if the patient tolerates the drugs and then decide which component needs to be titrated. It’s hard to titrate a combination drug, and it doesn’t leave a lot of flexibility. You never know which drug is doing what.
 

Dr. Handelsman said some patients may need to take three medications such as metformin, an SGLT2 inhibitor, and a GLP-1 receptor agonist.

“I don’t recommend using the combinations if you’re not familiar with the drugs ... These are relatively new pharmaceuticals, and most of us are on a learning curve as to how they fit into the armamentarium. If a drug is tolerated with a good response, you can certainly consider going to the combination tablets,” he added.

There is at least one drug that combines these three classes: The newly FDA-approved Qternmet XR, which combines dapagliflozin (an SGLT2 inhibitor), saxagliptin (a GLP-1 receptor agonist), and metformin. As of mid-June 2019, it was not yet available in the United States. Its sister drug Qtern, which combines dapagliflozin and saxagliptin, costs more than $500 a month with a free coupon, according to goodrx.com. In contrast, metformin is extremely inexpensive, costing just a few dollars a month for a common starting dose.
 

What about adding insulin?

“Both [SGLT2 inhibitors and GLP-1 receptor agonists] work very well with insulin,” Dr. Handelsman said. “There is a nice additive effect on the reduction of [hemoglobin] A_1c. The only caution is that, although neither SGLT2 inhibitors nor GLP-1 receptor agonists cause hypoglycemia, in combination with insulin they do increase the risk of hypoglycemia. You may have to adjust the dose of insulin.”

Dr. Hopkins warned that cost becomes an even bigger issue when you add insulin into the mix.

“When insulin comes into the discussion, we are again stuck with astronomical costs which many struggle to afford,” he explained.

Indeed, the price tag on these drugs seems to be the biggest problem physicians have with them.

“The challenges in managing patients with diabetes aren’t the risks associated with the drugs. It’s dealing with their insurers,” noted Dr. Roberts.

Dr. Hopkins, Dr. Paauw, Dr. Roberts, and Dr. Syed reported no disclosures. Dr. Buse is an investigator for Johnson and Johnson. Dr. Goldschmidt is paid to speak by Novartis. Dr. Handelsman reported research grants, consulting work, and speaker honoraria from Amgen, Gilead, Lilly, Merck, Novo Nordisk, and others. Dr Skolnik reported nonfinancial support from AstraZeneca, Boehringer Ingelheim, Sanofi, and GlaxoSmithKline and personal fees from AstraZeneca, Boehringer Ingelheim, and Eli Lilly. He also serves on the advisory boards of AstraZeneca, Boehringer Ingelheim, Teva Pharmaceutical, Eli Lilly, Sanofi, Janssen Pharmaceuticals, Intarcia, Mylan, and GlaxoSmithKline.

Dr. Paauw and Dr. Skolnik are columnists for Family Practice News and Internal Medicine News.

M. Alexander Otto contributed to this report.

klennon@mdedge.com

The options for treating type 2 diabetes without insulin have grown beyond metformin to include a long list of sodium-glucose cotransporter 2 (SGLT2) inhibitors and glucagonlike peptide–1 (GLP-1) receptor agonists that can be taken with or without metformin. These new drugs have cardiovascular and kidney benefits and help with weight loss, but they also carry risks and, according to some experts, their costs can be prohibitively expensive.
 

Given the medical community’s long-term experience with treating patients with metformin, and metformin’s lower cost, most of the physicians interviewed for this article advise using SGLT2 inhibitors and GLP-1 receptor agonists as second-line treatments. Others said that they would prefer to use the newer drugs as first-line therapies in select high-risk patients, but prior authorization hurdles created by insurance companies make that approach too burdensome.

“The economics of U.S. health care is stacked against many of our patients with diabetes in the current era,” Robert H. Hopkins Jr., MD, said in an interview.

Even when their insurance approves the drugs, patients still may not be able to afford the copay, explained Dr. Hopkins, professor of internal medicine and pediatrics and director of the division of general internal medicine at the University of Arkansas for Medical Sciences, Little Rock. “Sometimes patients can purchase drugs at a lower cost than the copay to purchase with the ‘drug coverage’ in their insurance plan – unfortunately, this is not the case with the newer diabetes medications we are discussing here.”

“SGLT2 inhibitors and GLP-1 agonists can cost several hundred dollars a month, and insurers often balk at paying for them. They’ll say, ‘Have you tried metformin?’ ” explained endocrinologist Victor Lawrence Roberts, MD, in a interview. “We have to work with insurance companies the best we can in a stepwise fashion.”

According to Dr. Roberts, 80% of his patients with diabetes struggle with the cost of medicine in general. “They’re either underinsured or not insured or their formulary is limited.

Douglas S. Paauw, MD, agreed in an interview that the newer drugs can be problematic on the insurance front.

“For some patients they aren’t affordable, especially for the uninsured if you can’t get them on an assistance program,” said Dr. Paauw, who is professor of medicine in the division of general internal medicine at the University of Washington, Seattle, and serves as third-year medical student clerkship director at the university.

Dr. Hopkins, who is on the Internal Medicine News board, noted that “unfortunately, the treatment of type 2 diabetes in patients who cannot achieve control with metformin, diet, weight control, and exercise is a story of the ‘haves’ and the ‘have nots.’ The ‘haves’ are those who have pharmacy benefits which make access to newer agents like SGLT2 inhibitors and GLP-1 agonists a possibility.”

“I have had very few of the ‘have nots’ who have been able to even consider these newer agents, which carry price tags of $600-$1,300 a month even with the availability of discounting coupons in the marketplace,” he added. “Most of these patients end up requiring a sulfonylurea or TZD [thiazolidinedione] as a second agent to achieve glycemic control. This makes it very difficult to achieve sufficient weight and metabolic control to avoid an eventual switch to insulin.”

Fatima Z. Syed, MD, an endocrine-trained general internist at DukeHealth in Durham, N.C., said she prescribes SGLT2 inhibitors and GLP-1 receptor agonists in combination with metformin. “I prescribe them frequently, but they are not first-line treatments,” she explained.

“Nothing replaces diet and exercise” as therapy for patients with type 2 diabetes, she added.

Neil S. Skolnik, MD, said that insurance companies were not preventing patients from using these drugs in his experience. He also provided an optimistic take on the accessibility of these drugs in the near future.

“Most insurance companies are now covering select SGLT2 inhibitors and GLP-1 receptor agonists for appropriate patients and those companies that currently do not will soon have to,” said Dr. Skolnik, who is a professor of family and community medicine at Jefferson Medical College, Philadelphia, and an associate director of the family medicine residency program at Abington (Pa.) Jefferson Health.

“The outcomes [associated with use of the new drugs] are robust, the benefits are large, and are well worth the cost,” he added.
 

 

The side effects

While others praised these drugs for their beneficial effects, they also noted that the side effects of these drugs are serious and must be discussed with patients.

GLP-1 receptor agonists are linked to gastrointestinal symptoms, especially nausea, while SGLT2 inhibitors have been linked to kidney failure, ketoacidosis, and more. The Food and Drug Administration warned in 2018 that the SGLT2 inhibitors can cause a rare serious infection known as Fournier’s gangrene – necrotizing fasciitis of the perineum.

“We have to tell our patients to let us know right away if they get pain or swelling in the genital area,” Dr. Paauw, who is on the Internal Medicine News board, noted. “The chance that an infection could explode quickly is higher in those who take these drugs.”

Amputation risks also are associated with taking the SGLT2 inhibitor canagliflozin (Invokana). The FDA requires the manufacturer of this drug to include a black-box warning about the risk of “lower-limb amputations, most frequently of the toe and midfoot,” but also the leg. In approval trials, the risk doubled versus placebo.

These amputation risks “put a damper on some of the enthusiasm on behalf of physicians and patients ... for taking this drug,” noted Dr. Roberts, who is a professor of internal medicine at the University of Central Florida, Orlando.

While a manufacturer-funded study released last year found no link to amputations, the results weren’t powerful enough to rule out a moderately increased risk.

“[If] you are at high risk for having an amputation, we really have to take this risk very seriously,” said John B. Buse, MD, chief of the division of endocrinology at the University of North Carolina at Chapel Hill, in a presentation about the study at the 2018 annual scientific sessions of the American Diabetes Association.
 

The benefits

Despite these risks of adverse events, most interviewed agreed that the many benefits observed in those taking SGLT2 inhibitors or GLP-1 receptor agonists make them worth prescribing, at least to those who are able to afford them.

Both SGLT2 inhibitors and GLP-1 receptor agonists appear to have significant cardiovascular benefits. A 2019 meta-­analysis and systematic review found that both drugs reduced major adverse cardiac events by about 12% (Circulation. 2019 Apr 23;139[17]:2022-31).

“They don’t cause hypoglycemia, they lower blood pressure, they don’t cause weight gain, and they might promote weight loss,” noted Dr. Paauw.

SGLT2 inhibitors also have shown signs of kidney benefits. The CREDENCE trial linked canagliflozin to a lowering of kidney disorders versus placebo (N Engl J Med. 2019 Jun 13;380[24]:2295-306). “The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% confidence interval, 0.53-0.81; P less than .001), and the relative risk of end-stage kidney disease was lower by 32% (HR, 0.68; 95% CI, 0.54-0.86; P = .002),” the trial investigators wrote.

“They showed very nicely that the drug improved the kidney function of those patients and reduced the kidney deterioration,” said Yehuda Handelsman, MD, an endocrinologist in Tarzana, Calif., who chaired the 2011 and 2015 American Association of Clinical Endocrinologists’ Comprehensive Diabetes Guidelines. The study was especially impressive, he added, because it included patients with low kidney function.

SGLT2 inhibitors’ “diuretic mechanism explains why there is a substantial reduction in heart failure hospitalizations in patients who take these drugs,” said cardiologist Marc E. Goldschmidt, MD, director of the Heart Success Program at Atlantic Health System’s Morristown (N.J.) Medical Center, in an interview. “Both the EMPA-REG Outcome and the CREDENCE trials demonstrated substantial benefit of this class of medications by showing a lower risk of cardiovascular death as well as death from any cause and a lower risk of hospitalization for heart failure."

Overall, the SGLT2 trial data have been very consistent with a benefit for cardiovascular risk reduction, particularly in regard to heart failure hospitalizations and even in potentially preventing heart failure in diabetics,” he added.

Dr. Skolnik, a columnist for Family Practice News, cited SGLT2 inhibitors and GLP-1 receptor agonists’ ability to slow renal disease progression, promote weight loss, and prevent poor cardiac outcomes.“These drugs should be used, in addition to metformin, in all patients with diabetes and vascular disease. These proven outcomes are far better than we ever were able to achieve previously and the strength of the evidence at this point is very strong,” said Dr. Skolnik. “In addition to the benefits of decreasing the development of cardiovascular disease, serious heart failure, and slowing progression of renal disease, these two classes of medication have additional benefits. Both classes help patients lose weight, which is very different from what was found with either sulfonylureas or insulin, which cause patients to gain weight. Also both the SGLT2 inhibitors and the GLP-1 RAs [receptor agonists] have a low incidence of hypoglycemia. For all these reasons, these have become important medications for us to use in primary care.”

Other recent trials offer “very powerful data” about SGLT2 inhibitors, Dr. Roberts said. That’s good news, since “our approach needs to be toward cardiovascular protection and preservation as well as managing blood sugar.”An Israeli trial, whose results were released in May 2019 at the annual meeting of the American College of Cardiology, found that, compared with other glucose-lowering drugs, taking an SGLT2 inhibitor was associated with lower risks of heart failure hospitalization and all-cause mortality (HR, 0.54; 95% CI, 0.44-0.65; P less than .001). This trial also offered a new detail: The patients gained the benefit regardless of whether their baseline left ventricular ejection fraction was preserved or reduced (J Coll Cardiol. 2019 Mar;73[9]:suppl 1). The SGLT2 inhibitors used in this trial included dapagliflozin (Farxiga) and empagliflozin (Jardiance).

In another study released this year, a subanalysis of the DECLARE-TIMI 58 trial, researchers reported that the SGLT2 inhibitor dapagliflozin reduced risks of both major adverse cardiovascular events and heart failure hospitalization in the subset of patients with type 2 diabetes and prior myocardial infarction versus controls (Circulation. 2019 May 28;139[22]:2516-27). The absolute risk reduction for major adverse cardiovascular events was 1.9% (HR, 0.81; 95% CI, 0.65-1.00; P = .046), while it was 0.6% for heart failure hospitalization (HR, 0.85; 95% CI, 0.72-1.00; P = .055).

These and other studies “speak volumes about the efficacy of managing blood sugar and addressing our biggest nemesis, which is cardiovascular disease,” Dr. Roberts said. “It’s irrefutable. The data [are] very good.”

Dr. Paauw said an SGLT2 inhibitor or GLP-1 receptor agonist is best reserved for use in select patients with cardiovascular risks and type 2 diabetes that need management beyond metformin.

For example, they might fit a 70-year-old with persistent hypertension who’s already taking a couple of blood pressure medications. “If they have another cardiovascular risk factor, the cardiovascular protection piece will be a bigger deal,” he said. Also, “it will probably help lower their blood pressure so they can avoid taking another blood pressure medicine.”

Trials of both GLP-1 receptor agonists and SGLT2 inhibitors have shown benefits “in improving [major adverse cardiac events], with the SGLT2 class showing substantial benefit in improving both heart failure and renal outcomes as well,” noted Dr. Skolnik. “It is in this context that one must address the question of whether the price of the medications are worthwhile. With such substantial benefit, there is no question in my mind that – for patients who have underlying cardiovascular illness, which includes patients with existent coronary disease, history of stroke, transient ischemic attack, or peripheral vascular disease – it is far and away worth it to prescribe these classes of medications.”

Indeed, the American Diabetes Association and the European Association for the Study of Diabetes’ most recent guidelines now call for a GLP-1 receptor agonist – instead of insulin – to be the first injectable used to treat type 2 diabetes (Diabetes Care 2018 Dec; 41[12]:2669-701).

“For the relatively small number of my patients who have been able to access and use these medications for months or longer, more have tolerated the GLP-1 agonists than SGLT2 inhibitors primarily due to urinary issues,” noted Dr. Hopkins.

Dipeptidyl peptidase–4 inhibitors are another option in patients with type 2 diabetes, but research suggests they may not be a top option for patients with cardiovascular risk. A 2018 review noted that cardiovascular outcome trials for alogliptin (Nesina), saxagliptin (Onglyza), and sitagliptin (Januvia) showed noninferiority but failed to demonstrate any superiority, compared with placebo in patients with type 2 diabetes mellitus and high cardiovascular risk (Circ Res. 2018 May 11;122[10]:1439-59).
 

 

The combination therapies

Many of the newer drugs are available as combinations with other types of diabetes drugs. In some cases, physicians create their own form of combination therapy by separately prescribing two or more diabetes drugs. Earlier this year, a study suggested the benefits of this kind of add-on therapy: Diabetes outcomes improved in patients who took the GLP-1 receptor agonist semaglutide and an SGLT2 inhibitor (Lancet Diabetes Endocrinol. 2019 Mar 1. doi: 10.1016/S2213-8587[19]30066-X).

 

Dr. Roberts suggested caution, however, when prescribing combination therapies. “My recommendation is always to begin with the individual medications to see if the patient tolerates the drugs and then decide which component needs to be titrated. It’s hard to titrate a combination drug, and it doesn’t leave a lot of flexibility. You never know which drug is doing what.
 

Dr. Handelsman said some patients may need to take three medications such as metformin, an SGLT2 inhibitor, and a GLP-1 receptor agonist.

“I don’t recommend using the combinations if you’re not familiar with the drugs ... These are relatively new pharmaceuticals, and most of us are on a learning curve as to how they fit into the armamentarium. If a drug is tolerated with a good response, you can certainly consider going to the combination tablets,” he added.

There is at least one drug that combines these three classes: The newly FDA-approved Qternmet XR, which combines dapagliflozin (an SGLT2 inhibitor), saxagliptin (a GLP-1 receptor agonist), and metformin. As of mid-June 2019, it was not yet available in the United States. Its sister drug Qtern, which combines dapagliflozin and saxagliptin, costs more than $500 a month with a free coupon, according to goodrx.com. In contrast, metformin is extremely inexpensive, costing just a few dollars a month for a common starting dose.
 

What about adding insulin?

“Both [SGLT2 inhibitors and GLP-1 receptor agonists] work very well with insulin,” Dr. Handelsman said. “There is a nice additive effect on the reduction of [hemoglobin] A_1c. The only caution is that, although neither SGLT2 inhibitors nor GLP-1 receptor agonists cause hypoglycemia, in combination with insulin they do increase the risk of hypoglycemia. You may have to adjust the dose of insulin.”

Dr. Hopkins warned that cost becomes an even bigger issue when you add insulin into the mix.

“When insulin comes into the discussion, we are again stuck with astronomical costs which many struggle to afford,” he explained.

Indeed, the price tag on these drugs seems to be the biggest problem physicians have with them.

“The challenges in managing patients with diabetes aren’t the risks associated with the drugs. It’s dealing with their insurers,” noted Dr. Roberts.

Dr. Hopkins, Dr. Paauw, Dr. Roberts, and Dr. Syed reported no disclosures. Dr. Buse is an investigator for Johnson and Johnson. Dr. Goldschmidt is paid to speak by Novartis. Dr. Handelsman reported research grants, consulting work, and speaker honoraria from Amgen, Gilead, Lilly, Merck, Novo Nordisk, and others. Dr Skolnik reported nonfinancial support from AstraZeneca, Boehringer Ingelheim, Sanofi, and GlaxoSmithKline and personal fees from AstraZeneca, Boehringer Ingelheim, and Eli Lilly. He also serves on the advisory boards of AstraZeneca, Boehringer Ingelheim, Teva Pharmaceutical, Eli Lilly, Sanofi, Janssen Pharmaceuticals, Intarcia, Mylan, and GlaxoSmithKline.

Dr. Paauw and Dr. Skolnik are columnists for Family Practice News and Internal Medicine News.

M. Alexander Otto contributed to this report.

klennon@mdedge.com