Diabetes Care Volume 37, July 2014 1797 IBTSCARE SYMPOSIUM

Signe H. Østoft,1,2,3 Jonatan I. Bagger,1,2,3 Glucose-Lowering Effects and Low Torben Hansen,3,4 Oluf Pedersen,3 Jens Faber,5,6 Jens J. Holst,2,3 Risk of Hypoglycemia in Patients Filip K. Knop,1,2,3 and Tina Vilsbøll1,6 With Maturity-Onset Diabetes of the Young When Treated With a GLP-1 Agonist: A Double- Blind, Randomized, Crossover Trial Diabetes Care 2014;37:1797–1805 | DOI: 10.2337/dc13-3007

OBJECTIVE The most common form of maturity-onset diabetes of the young (MODY), hepa- tocyte nuclear factor 1a (HNF1A diabetes: MODY3) is often treated with sulfonyl- ureas that confer a high risk of hypoglycemia. We evaluated treatment with GLP-1 receptor agonists (GLP-1RAs) in patients with HNF1A diabetes.

RESEARCH DESIGN AND METHODS Sixteen patients with HNF1A diabetes (8 women; mean age 39 years [range 23–67 years]; BMI 24.9 6 0.5 kg/m2 [mean 6 SEM]; fasting plasma glucose [FPG] 9.9 6

0.9 mmol/L; HbA1c 6.4 6 0.2% [47 6 3 mmol/mol]) received 6 weeks of treatment with a GLP-1RA (liraglutide) and placebo (tablets), as well as a sulfonylurea (gli- 1Diabetes Research Division, Department of mepiride) and placebo (injections), in randomized order, in a double-blind, cross- Medicine, Gentofte Hospital, University of Co- over trial. Glimepiride was up-titrated once weekly in a treat-to-target manner; penhagen, Hellerup, Denmark liraglutide was up-titrated once weekly to 1.8 mg once daily. At baseline and at the 2Department of Biomedical Sciences, Faculty end of each treatment period a standardized liquid meal test was performed, of Health Sciences, University of Copenhagen, Copenhagen, Denmark including a 30-min light bicycle test. 3NNF Center for Basic Metabolic Research, Uni- versity of Copenhagen, Copenhagen, Denmark RESULTS 4Faculty of Health Sciences, University of South- FPG decreased during the treatment periods (21.6 6 0.5 mmol/L liraglutide ern Denmark, Odense, Denmark 5 [P = 0.012] and 22.8 6 0.7 mmol/L glimepiride [P = 0.003]), with no difference Department of Medicine, Herlev Hospital, Uni- P versity of Copenhagen, Herlev, Denmark between treatments ( = 0.624). Postprandial plasma glucose (PG) responses 6Faculty of Health Sciences, University of Copen- (total area under the curve) were lower with both glimepiride (2,136 6 292 hagen, Copenhagen, Denmark min 3 mmol/L) and liraglutide (2,624 6 340 min 3 mmol/L) compared with Corresponding author: Signe H. Østoft, s.ostoft@ baseline (3,127 6 291 min 3 mmol/L; P < 0.001, glimepiride; P = 0.017, liraglutide), dadlnet.dk. with no difference between treatments (P = 0.121). Eighteen episodes of hypogly- Received 23 December 2013 and accepted 23 cemia (PG £3.9 mmol/L) occurred during glimepiride treatment and one during April 2014. liraglutide treatment. Clinical trial reg. nos. EudraCT2012-000592-17, http://eudract.ema.europa.eu/, and NCT01610934, CONCLUSIONS clinicaltrials.gov. Six weeks of treatment with glimepiride or liraglutide lowered FPG and postpran- A slide set summarizing this article is available online. dial glucose excursions in patients with HNF1A diabetes. The glucose-lowering © 2014 by the American Diabetes Association. effect was greater with glimepiride at the expense of a higher risk of exclusively See http://creativecommons.org/licenses/by- mild hypoglycemia. nc-nd/3.0/ for details. 1798 GLP-1R Agonist vs. Sulfonylurea in MODY3 Diabetes Care Volume 37, July 2014

Maturity-onset diabetes of the young hypoglycemia for 12 h. In contrast to IV); plasma creatinine concentrations (MODY) is responsible for 1–2% of all the glucose-independent insulinotropic .130 mmol/L and/or albuminuria; cases of diabetes. MODY is a heritable, effect of SUs, GLP-1 receptor agonists disease (alanine aminotransferase and/or monogenic form of diabetes, is not in- (GLP-1RAs) exert an insulinotropic effect aspartate aminotransferase more than sulin dependent at onset, and often is in a strictly glucose-dependent manner, twice the upper limit of normal serum diagnosed at a young age (1). It is genet- with no effect at PG concentrations concentrations); anemia; acute or ically heterogeneous; mutations in ,4–5 mmol/L (12,13), translating into a chronic pancreatitis; goiter or thyroid more than eight different give low risk of hypoglycemia. Therefore, GLP- cancer; pregnancy or breast feeding; in- rise to specific forms of MODY. The ma- 1RA treatment might be safe and effica- ability to complete the trial; treatment- jority of patients who are diagnosed cious for patients with HNF1A diabetes, na¨ıve patients with HbA1c ,7.0% (53 with MODY have mutations in the hepa- but so far only a few cases have been mmol/mol); treatment with medicine tocyte nuclear factor 1a (HNF1A) reported (14–16). that could not be paused for 12 h; and (HNF1A diabetes, or MODY3) (2–5). The objectives of this trial were to knownallergytotrialmedication. HNF1Adiabetesischaracterizedby compare the effects of 6 weeks of treat- rapid progression from impaired glu- ment with the GLP-1RA liraglutide and Trial Medication cose tolerance to a progressive diabetes glimepiride on fasting PG (FPG) and the After a 1-week washout of blood glucose– due to a continuous loss of b-cell func- risk of hypoglycemia in patients with lowering drugs, patients were random- tion (4,6). HNF1A diabetes often devel- HNF1A diabetes. ized to receiving either 1) once-daily ops abruptly with classic hyperglycemic injections of liraglutide plus placebo tab- symptoms such as polyuria and polydip- RESEARCH DESIGN AND METHODS lets or 2) once-daily injections of placebo sia, which is why misclassification as Trial Design and End Points plus glimepiride tablets for 6 weeks. After type 1 diabetes (7) frequently occurs. This double-blind, randomized, cross- ending the first treatment period and Patients with HNF1A diabetes have the over trial was conducted from Septem- following a 1-week washout, patients re- same risk of developing diabetic micro- ber 2012 to August 2013 in accordance ceived the treatment that they were not and macrovascular complications as pa- with the International Conference on randomized to in period 1. Randomiza- tients with , and strict Harmonization Guidelines for Good Clini- tion codes were provided by the central glycemic control combined with proper cal Practice and the Declaration of Helsinki. hospital pharmacy, and the patients were treatment of complications is crucial All clinical visits and experiments were allocated to treatment groups by a non- for a good prognosis. The HNF1A defect conducted at Diabetes Research Center, blinded colleague who was otherwise not results in reduced concentrations of ATP Department of Medicine, Gentofte Hos- involved in the trial. Adequate randomi- in b-cells, which in turn lowers insulin pital, University of Copenhagen, Copen- zation was ensured by stratification based secretion. Sulfonylureas (SUs) bind to a hagen, Denmark. on a computer-generated random num- membrane closely related to the The primary end point was FPG after ber sequence. The principal investigator ATP-dependent potassium (K+)channel 6 weeks of treatment. Secondary end (S.H.Ø.) enrolled the patients but re- (KATP channel) in the b-cell, thereby points encompassed the number and mained blinded throughout the trial pe- closing the channel (8). Closing the severity of hypoglycemic episodes, riod and data analyses. Eight patients KATP channel causes membrane depolar- serum fructosamine, and responses started taking liraglutide plus placebo ization, leading to the opening of of pancreatic hormones (insulin, and 8 patients started taking glimepiride the voltage-gated calcium (Ca2+)chan- C-peptide, and glucagon) and counter- plus placebo. Liraglutide (Victoza) and nel and increasing intracellular Ca2+ con- regulatory hormones (growth hormone, placebo injection pens were indistin- centration, eliciting insulin secretion. cortisol, epinephrine, and norepineph- guishable (provided in sequentially num- Hence, the use of SUs in patients with rine) following a test meal combined bered containers) and provided by Novo HNF1A diabetes can bypass their re- with a 30-min bicycle test. Nordisk A/S; identical appearing glimepir- duced concentrations of ATP and stimu- After receiving thorough information ide and placebo tablets (encapsulation) late insulin secretion. Because of a high about the trial and signing informed were provided by the central hospital sensitivity to SUs (4,9,10) combined with consent, each patient was screened pharmacy. Capsules with glimepiride normal or even increased insulin sensi- and evaluated according to inclusion and placebo were each provided in 0.5 tivity, this treatment is effective in low- and exclusion criteria. Inclusion criteria and 1.0 mg doses. Patients were initiated ering of plasma glucose (PG). However, included Caucasian race, presence of on a dose of glimepiride, which was because of the glucose-independent HNF1A diabetes, older than 18 years of 0.5 mg lower than their regular daily mechanism of SUs, treatment often is age; BMI .19 kg/m2; normal hemoglobin dose of glimepiride (or the analogous associated with hypoglycemia even of .8.2 mmol/L (males) and .7.2 dose of another SU), and up-titrated when using relatively low doses (4,11). mmol/L (females); normal blood pres- with 0.5 mg glimepiride/placebo daily ev- In 2006, Tuomi et al. (11) demonstrated sure (,160/100 mmHg); informed con- ery week in a treat-to-target manner that during physical exercise in patients sent; capability of performing a light (weekly mean FPG goal in the range of with HNF1A diabetes (light cycling for 30 cycling test (heart rate 100–120 5.0–5.9 mmol/L). Liraglutide/placebo min approximately 2 h after ingesting a bpm during 30 min); use of intrauterine was initiated at 0.6 mg once daily and meal), hypoglycemia was observed in or hormonal contraception (women). escalated by 0.6 mg every week to the 40% of subjects treated with an SU (gli- Exclusion criteria included heart failure target dose of 1.8 mg once daily. During benclamide); one patient experienced (New York Heart Association class III or the full trial period of 14 weeks (2 periods care.diabetesjournals.org Østoft and Associates 1799

of 6 weeks of treatment and 2 1-week Each patient was served a standardized Blood Samples washouts) the patients self-monitored liquid test meal consisting of 250 mL Blood was collected into dry tubes for blood glucose (SMBG) and registered epi- Nutridrink Compact (Nutricia, Allerød, coagulation (20 min at room tempera- sodes of hypoglycemia and trial medica- Denmark) containing 375 kcal (46 g car- ture) for analyses of insulin, C-peptide, tion dosages in a diary. Hypoglycemia was bohydrate, 14.5 g fat, 15 g protein). fructosamine, cortisol, and growth hor- classified as 1) mild hypoglycemia (docu- Acetaminophen (Panodil) 1.5 g dis- mone (somatotropine). To analyze glu- mented symptomatic hypoglycemia con- solved in 50 mL water was added to cagon, blood was collected into chilled firmed by PG reading ,4.0 mmol/L or evaluate gastric emptying. The patients tubes containing EDTA and aprotinin asymptomatic hypoglycemia with PG were examined after a 10-h overnight (500 kIU/mL blood; Trasylol; Bayer, ,4.0 mmol/L) or 2) severe hypoglycemia fast. The trial medication was taken 30 Leverkusen, Germany). To analyze (symptoms of hypoglycemia with need min before the test meal (ingested from catecholamines (epinephrine and nor- for assistance from another person). If time 0–10min).Nomedicationwas epinephrine), blood was collected into no PG value was available, neurological taken at the baseline visit. A 30-min bi- chilled tubes containing a mixture of recovery following normalization of cycling test (target heart rate 100–120 ethyleneglycol tetraacetic acid, re- PG was considered sufficient evidence bpm) was performed at time 150–180 duced glutathione, sodium hydroxide, of hypoglycemia. min. Symptoms of hypoglycemia were and water. To analyze acetaminophen monitored, and PG concentrations (Panodil; GlaxoSmithKline A/S, Copen- Clinical Visits were measured at prespecified time hagen, Denmark), blood was collected Experiments took place on three occa- points and in the event of symptoms into chilled tubes containing heparin. sions: at baseline (after washout of of hypoglycemia. Blood samples also EDTA, heparin, and tubes for analysis blood glucose–lowering drugs) and at were drawn at prespecified time points, of catecholamines were immediately the end of both treatment periods. as indicated in Fig. 1. cooled and kept on ice until centrifugation.

Figure 1—Glucose and hormone responses: PG (A), plasma glucagon (B), plasma acetaminophen (C), serum insulin (D), serum C-peptide (E), ISR (F), serum somatotropine (growth hormone) (G), serum cortisol (H), serum norepinephrine (I). Data are mean values 6 SEMs derived from a standard- ized liquid meal test at baseline (black line; after a 1-week washout of blood glucose–lowering drugs) and at the end of each period of treatment with liraglutide (orange line) and glimepiride (purple line). *Significant difference (P , 0.05) from baseline with both treatments, but no difference between treatments. †Significant difference (P , 0.05) between baseline and glimepiride. ‡Significant difference (P , 0.05) from glimepiride of both baseline and liraglutide but no difference between baseline and liraglutide. Further details are provided in Tables 2 and 3. iAUC, incremental area under the curve. 1800 GLP-1R Agonist vs. Sulfonylurea in MODY3 Diabetes Care Volume 37, July 2014

All samples were centrifuged for 20 min according to likelihood ratios. Bonfer- from the trial 4 days after randomization at 1,200g and 48C. Serum samples for in- roni adjustments were used as post because of diarrhea, nausea, and vomit- sulin, C-peptide, fructosamine, cortisol, hoc analysis. Baseline, peak, and area ing during initiation of the first treat- and growth hormone analyses and under the curve (AUC) values are ex- ment period (liraglutide), but the rest plasma samples for catecholamine anal- pressed as mean 6 SEM. Differences (15 patients) adhered to the protocol. yses were stored at 2808C until analysis; resulting in P values ,0.05 were consid- Data from the withdrawn patient are ex- plasma samples for acetaminophen and ered significant. AUC values were calcu- cluded from the analyses. Patients 1 and glucagon analyses were stored at 2208C lated using the trapezoidal rule and are 14, as well as patients 6 and 11 (Table 1), until analysis. For bedside glucose mea- presented as total AUCs (tAUCs) if not were first-degree relatives (mother/ surements, blood was collected into fluo- otherwise stated. Insulin secretion rate daughter). ride tubes followed by immediate (ISR) values were calculated by decon- centrifugation at 7,400g for 2 min at voluting measured C-peptide concentra- Glycemic Regulation Time courses for PG from the meal tests room temperature. tions and applying population-based are illustrated in Fig. 1A. FPG, minimum, parameters for C-peptide kinetics, as de- peak, AUC, fructosamine, HbA ,and Analytical Procedures scribed previously (21–23). ISR is ex- 1c During the meal tests, PG concentra- HOMA-IR values are given in Table 2. pressed as picomoles of insulin secreted tions were measured by the glucose ox- Both treatments resulted in significantly per minute per kilogram body weight. In- idase method, using a glucose analyzer lower FPG compared with baseline. FPG sulin resistance was calculated according (Yellow Springs Instrument Model 2300 tended to be lower during glimepiride to HOMA (HOMA-IR) from fasting plasma STAT Plus analyzer; YSI Inc., Yellow treatment than during treatment with insulin and FPG (24). The number and se- Springs, OH). SMBGs were measured us- liraglutide. Both treatments exhibited verity of hypoglycemic episodes was reg- ing standard glucose meters (Contour lower minimum values compared with istered on experimental days and from next USB glucose meter; Bayer, Ger- baseline; glimepiride lowered peak PG. SMBG and diaries. many). Serum insulin and C-peptide For minimum values, glimepiride treat- The primary outcome (FPG) was used concentrations were measured using a ment showed lower values than liraglu- to calculate the sample size. With an two-sided electrochemiluminescence tide treatment, but no difference in the expected end-of-treatment value of 8.4 immunoassay (Siemens Healthcare, peak values of the treatments was mmol/L (SD 2.5) (25), and with a set to Ballerup, Denmark) (17,18). Serum found. Glucose responses (tAUC) were 5% and statistical power to 80%, the es- fructosamine concentrations were mea- different from baseline, but only glime- timated sample size was 12 in each arm sured using a colorimetric assay (Roche, piride lowered incremental AUC, and to detect a difference in FPG of 2 mmol/L. Germany). Serum somatotropine (growth no difference between the treatments We included 16 patients in each arm to hormone) was measured using chemilu- was found. Fructosamine, HbA ,and increase the statistical power of the pri- 1c minescence immunoassay (IDS Nordic, HOMA-IR levels were unaltered from mary end point. Denmark), and serum cortisol was mea- baseline to the end of each treatment sured using a competitive immunoassay RESULTS period, and no difference was found be- (ADVIA Centaur CP; Siemens Healthcare). tween the treatments. Participants The glucagon assay is directed against Anthropometric data (from screening Hypoglycemia the COOH-terminal of the glucagon mol- visit) are given in Table 1. Sixteen pa- A total of 19 hypoglycemic events were ecule (antibody code no. 4305) (19). tients were included (8 women, 8 men) reported; 10 events were reported by Plasma acetaminophen was measured with the following characteristics at the SMBG and 9 events were reported on by the Vitros ACET slide method (Ortho- screening visit: age 39 years (range 23– experimental days. One event was re- Clinical Diagnostics, Johnson & Johnson, 67 years); mean BMI 6 SEM 24.9 6 ported during treatment with liraglutide Denmark). Plasma catecholamines were 0.5 kg/m2;HbA 6.4 6 0.2% (47 6 3 (minimum value 3.5 mmol/L) and 18 measured using noradrenaline and adren- 1c mmol/mol). All patients had a disease- events during treatment with glimepir- alineresearchELISAs(LaborDiagnostika causing heterozygous loss-of-function ide (mean minimum value 6 SEM 3.3 6 Nord, Germany). Heart rate was moni- mutation in HNF1A confirmed by Sanger 0.1 mmol/L). All episodes of hypoglyce- tored with a Garmin Forerunner310XT sequencing of the gene. Fifteen patients mia were mild. In 17 of the events, blood watch and heart rate sensor. were treated with oral blood glucose– glucose was in the range of 3.1–3.9 Statistical Methods lowering drugs at inclusion (glimepiride mmol/L, and in 2 events it was in the Linear mixed-effect modeling was [n = 11]; repaglinide [n = 2]; tolbutamide range of 2.0–3.0 mmol/L. Symptoms of used for analysis of repeated measures [n = 1]; gliclazide [n = 1]), and one patient hypoglycemia were present during 14 using R statistical software (R Foun- was treated with diet only. Apart from events, including the 2 events in dation for Statistical Computing, their regular blood glucose–lowering the lower range and the single event Wirtschaftsuniversitat,¨ Vienna, Austria). drugs, none of the patients used any during liraglutide treatment. No symp- Data were transformed according to drugs suspected of influencing glucose toms were present during the five distribution pattern. A “top-down” tolerance or insulin, C-peptide, or incre- events measured during experimental modeling strategy, with family identity tin hormone responses. One patient days. During glimepiride treatment, 10 as random variable, was used (20). (woman, age 24 years, BMI 20.5 kg/m2, patients (67%) experienced a hypoglyce- A homogeneous or heterogeneous re- HbA1c 5.6% [38 mmol/mol], treated with mic event: 6 patients had 1 event, 1 pa- sidual variance structure was chosen glimepiride before inclusion) withdrew tient had 2 events, 2 patients had 3 care.diabetesjournals.org Østoft and Associates 1801 aaaedrvdfo h cenn ii ( visit screening the from derived are Data Mean 6M2 4473(6 lmprd . mg 1.0 Glimepiride (56) 7.3 24.4 28 M 16 5M4 7963(5 lmprd . mg 3.0 Glimepiride (45) 6.3 27.9 42 M 15 4 62. . 6)Gieiie40mg 4.0 Glimepiride (63) 7.9 24.5 56 F 14* 3M2 6055(7 lmprd . mg 1.5 Glimepiride (37) 5.5 26.0 29 M 13 2M3 7570(3 lmprd . mg 1.0 Glimepiride (53) 7.0 27.5 34 M 12 11 9F2 1354(6 ealnd mg 1 Repaglinide (36) 5.4 21.3 25 F 09 0F6 2966(9 lmprd . mg 4.0 Glimepiride (49) 6.6 22.9 67 F 10 5M2 5170(3 otetet181.0 1.8 mg 30 Gliclazide treatment No (51) 6.8 mg 0.5 Repaglinide (53) 7.0 (48) 6.5 26.7 25.1 24.4 71 24 38 M M M 08 07 06 05 04 2F5 6565(8 obtmd 0 5 5 g182.5 1.8 mg mg 1.5 250 + Glimepiride 250 + 500 Tolbutamide (36) 5.4 (48) 6.5 24.3 26.5 27 54 M F 03 02 1 72. . 6)Gieiie15mg 1.5 Glimepiride (65) 8.1 24.0 27 F 01* al 1 Table irhadrn h ntaino the of initiation the during diarrhea ain Sex Patient events, and 1 patient had 4 events. In † ‡ † contrast, only one patient (7%) experi-

6 enced hypoglycemia during liraglutide — E 9(ag 23 (range 39 SEM

nhooercdt fptet ( patients of data Anthropometric treatment (this patient experienced three events during glimepiride treat- ment). No hypoglycemic episodes oc- 32. . 4)Gieiie15mg 1.5 Glimepiride (46) 6.4 26.4 53 F 42. . 3)Gieiie10mg 1.0 Glimepiride mg 0.5 Glimepiride (38) 5.6 (28) 4.7 20.5 25.4 24 23 F F curred during washout weeks and at the experimental day at baseline. The two events in the low range occurred during glimepiride treatment but were not related to physical activity. In total, (years) fi s ramn eid(ialtd . g nedaily). once mg, 0.6 (liraglutide period treatment rst Age six episodes occurred during the cycling

n test (mean minimum value 6 SEM 3.4 6 – 6.F eae ,ml;N,ntapial.* applicable. not NA, male; M, female; F, 16). = 7 24.9 67) 0.1 mmol/L), including the single event during liraglutide treatment. n women, 8 = Insulin, C-peptide, and ISR (kg/m

BMI Figure 1 illustrates time courses for in- 6 2 . 6.4 0.5 sulin (panel D), C-peptide (panel E), and ) ISR (panel F), and fasting, peak, and AUC n

men) 8 = serum values are given in Table 2. No differences in fasting values of insulin (mmol/mol)

6 were found from baseline or between HbA

. (47 0.2 treatments, but similarly higher fasting 1c

,% C-peptide and ISR values were found

6 during both treatments compared with

)1.8 3) baseline. Both treatments exhibited † ainsaerltd(ohraddaughter). and (mother related are Patients higher peak values and responses of in- sulin and C-peptide compared with baseline but no differences between treatments. Both treatments resulted rg tinclusion at drugs Glucose-lowering in superior peak ISR values and re- sponses (tAUC) compared with baseline;

3 there was no difference in peak values 3 . 3.0 1.8 1 3 3 3 3 3 3 3 3 3 3 3 3

. 1.0 1.8 1 between the treatments, but glimepir- . 1.0 1.8 1 . . 3 1 2.0 1.8 1 . 4.0 1.8 1 . 1.5 1.8 1 . 3.5 1.8 1 . 4.0 1.8 1 . 3.5 1.8 1 . 4.0 1.8 1 . 1.0 1.8 1NANA1 . 4.0 1.8 1 . 3.0 1.8 2 ide treatment showed a higher ISR re- sponse (incremental AUC) than with liraglutide treatment. Glimepiride gen- erally exhibited a greater insulin secre- tory response than liraglutide, although ‡ ain ihrwfo h ra eas fitlrbevmtn and vomiting intolerable of because trial the from withdrew Patient ialtd lmprd ialtd Glimepiride Liraglutide Glimepiride Liraglutide the differences in tAUC were not statis- tically significant. 6 n oe(mg) dose End 02.5 Glucagon Time courses for glucagon are illus- trated in Fig. 1B, and fasting, peak, and AUC plasma values are given in Table 2. 6

. 18 1 0.3 Similar fasting and peak glucagon values and responses were found at baseline and during both treatments. During the bicycle test (150–180 min) (Fig. 1B), there was a tendency toward a yolcmcevents, Hypoglycemic d dd dd d dd d d d d d d dd d dd dd higher glucagon response during glime- ialtd ( liraglutide piride treatment.

Acetaminophen Time courses for acetaminophen are il- n ) 2 3 4 1 1 1 1 1 1 lustratedinFig.1C, and fasting, peak, and AUC plasma values are given in Table 3. No differences in gastric emp- tying were found from baseline or 1802 GLP-1R Agonist vs. Sulfonylurea in MODY3 Diabetes Care Volume 37, July 2014

Table 2—Glucose, insulin, C-peptide, ISR, and glucagon values by treatment group Baseline (0) Liraglutide (1) Glimepiride (2) (n =15) (n =15) (n =15) P* Glucose FPG (mmol/L) 9.9 6 0.8†(1,2) 8.2 6 0.8†(0) 7.2 6 0.6†(0) 0.002 Minimum PG (mmol/L) 9.3 6 0.9†(1,2) 7.5 6 0.9†(0,2) 5.2 6 0.7†(0,1) ,0.001 Peak PG (mmol/L) 15.8 6 1.3†(2) 14.2 6 1.5 12.7 6 1.2†(0) 0.029 tAUC (min 3 mmol/L) 3,127 6 291†(1,2) 2,624 6 340†(0) 2,136 6 292†(0) ,0.001 iAUC (min 3 mmol/L) 746 6 131†(2) 637 6 164 430 6 171†(0) 0.018 Fructosamine (mmol/L) 294 6 16 296 6 20 273 6 14 0.170

HbA1c (%) 6.6 6 0.3 6.7 6 0.4 6.2 6 0.3 0.260 HbA1c (mmol/mol) 48 6 3496 5446 30.223 HOMA-IR 3.0 6 0.5 2.6 6 0.5 2.5 6 0.3 0.501 Insulin Fasting (pmol/L) 46 6 6506 7576 70.372 Peak values (pmol/L) 216 6 29†(1,2) 314 6 54†(0) 354 6 46†(0) ,0.001 tAUC (min 3 nmol/L) 23 6 3†(1,2) 34 6 7†(0) 36 6 3†(0) ,0.001 iAUC (min 3 nmol/L) 12 6 2†(1,2) 22 6 5†(0) 23 6 3†(0) ,0.001 C-peptide Fasting (pmol/L) 376 6 46 443 6 44†(0) 452 6 39†(0) 0.012 Peak values (pmol/L) 1,000 6 130†(1,2) 1,345 6 177†(0) 1,408 6 132†(0) ,0.001 tAUC (min 3 nmol/L) 163 6 22†(1,2) 207 6 30†(0) 219 6 19†(0) ,0.001 iAUC (min 3 nmol/L) 73 6 12†(1,2) 100 6 21†(0) 110 6 14†(0) ,0.001 ISR Fasting (pmol/kg/min) 1.3 6 0.2†(1,2) 1.5 6 0.2†(0) 1.5 6 0.1†(0) 0.035 Peak values (pmol/kg/min) 5.4 6 0.8†(1,2) 7.1 6 0.9†(0) 8.1 6 1.1†(0) 0.002 tAUC (pmol/kg) 613 6 89†(1,2) 783 6 127†(0) 821 6 80†(0) ,0.001 iAUC (pmol/kg) 268 6 44†(2) 382 6 93†(2) 421 6 61†(0,1) 0.011 Glucagon Fasting (pmol/L) 26 6 7236 5216 60.434 Peak values (pmol/L) 58 6 15 51 6 12 47 6 11 0.104 tAUC (min 3 nmol/L) 8 6 376 276 20.473 iAUC (min 3 nmol/L) 2 6 126 126 10.565 Data are mean values 6 SEM derived from a standardized liquid meal test at baseline (0) (after a 1-week washout of blood glucose–lowering drugs) and at the end of each period of treatment with liraglutide (1) and glimepiride (2). iAUC, incremental area under the curve. *P values are derived from repeated-measures ANOVA for variations between treatments and baseline. †Significant difference (P , 0.05) from the period given in parentheses (post hoc analysis).

between the treatments according to response was found compared with vomiting and diarrhea, which was mod- peak acetaminophen, AUC, or to time baseline, and this response was similar erate and made the patient withdraw to peak values. to that found after glimepiride treat- from the trial) and transient. Except for ment. Both treatments tended to sup- the report of tiredness and one report of Counterregulatory Hormones press cortisol responses (Fig. 1H and reduced appetite, all nonhypoglycemic Time courses for the counterregulatory Table 3). No differences in fasting or events occurred during liraglutide hormones are illustrated in Fig. 1 peak plasma concentrations of norepi- treatment. (growth hormone [panel G]; cortisol nephrine (Fig. 1I and Table 3) or epi- [panel H]; norepinephrine [panel I]), nephrine (Table 3) were found. An and fasting, peak, and AUC values are CONCLUSIONS increased counterregulatory response given in Table 3. Similar fasting serum The primary findings of this randomized, of epinephrine, but not norepinephrine, growth hormone concentrations, peak double-blind, crossover trial were 1) was seen during glimepiride treatment values, and responses were found at FPG was reduced after 6 weeks of treat- (Table 3). baseline and during both treatments. A ment with liraglutide and glimepiride, 2) tendency toward an increased counter- Adverse Events glimepiride treatment had a more pro- regulatory growth hormone response Adverse events reported during the trial nounced effect on glucose excursions was seen during the bicycle test (150– period primarily concerned hypoglyce- compared with liraglutide treatment, 180 min) (Fig. 1G) during glimepiride mia; other events included tiredness and 3) there was an almost 10-fold treatment. The interventions did not af- (one report), reduced appetite (two re- higher risk of exclusively mild hypogly- fect fasting serum cortisol concentra- ports), heartburn (one report), nausea cemia during glimepiride treatment tions, but comparably lower peak (one report), and vomiting and diarrhea compared with liraglutide treatment. values were observed during both treat- (one report). All events were evaluated A crossover design was chosen be- ments compared with baseline. During as being related to trial medication and cause of the low prevalence of HNF1A liraglutide treatment, a lower cortisol weremild(exceptforthecaseof diabetes. Patients were included only care.diabetesjournals.org Østoft and Associates 1803

fi Table 3—Acetaminophen, growth hormone, cortisol, norepinephrine, others and may bene t from alternative and epinephrine values by treatment group treatment (i.e., liraglutide). Baseline (0) Liraglutide (1) Glimepiride (2) GLP-1 receptor activation on b-cells (n =15) (n =15) (n =15) P* results in activation of adenylate cyclase Acetaminophen and subsequent elevation of cAMP. Fasting (mmol/L) 0 6 006 006 00.524Both cAMP and activated protein kinase Peak values (mmol/L) 0.11 6 0.01 0.11 6 0.01 0.11 6 0.01 0.535 Amayinfluence secretory events distal tAUC (min 3 mmol/L) 17 6 1186 1186 10.345to the generation of ATP by glucose me- iAUC (min 3 mmol/L) 16 6 1176 1176 10.320tabolism (28–30). Our hypothesis was Time to peak (min) 82 6 6966 8856 50.138that, like SUs, a GLP-1RA might be capa- Growth hormone ble of bypassing the decreased concen- m 6 6 6 Fasting ( g/L) 1.4 0.6 1.9 0.8 1.6 0.5 0.591 trations of ATP and thereby stimulate Peak values (mg/L) 4.1 6 1.0 4.2 6 1.1 5.2 6 1.0 0.288 tAUC (min 3 mg/L) 368 6 81 446 6 125 499 6 112 0.098 secretion of insulin and consequently iAUC (min 3 mg/L) 24 6 96 27 6 127 119 6 153 0.717 reduce PG. In addition, GLP-1 may Cortisol have direct effect on the KATP channel Fasting (nmol/L) 390 6 34 327 6 30 336 6 19 0.074 (31,32). Peak values (nmol/L) 505 6 32†(1,2) 398 6 34†(0) 415 6 22†(0) 0.011 In this trial, treatment with both an tAUC (min 3 mmol/L) 78 6 5†(1,2) 67 6 5†(0) 69 6 5†(0) 0.039 SU and a GLP-1RA reduced FPG and iAUC (min 3 mmol/L) 215 6 7 211 6 5 211 6 40.780postprandial glucose excursions; this Norepinephrine occurred to the greatest extent during 6 6 6 Fasting (ng/mL) 0.33 0.04 0.26 0.04 0.25 0.03 0.125 glimepiride treatment. These results Peak values (ng/mL) 0.95 6 0.09 0.99 6 0.12 0.86 6 0.10 0.238 correlate well with the theory that glime- tAUC (min 3 ng/mL) 100 6 9996 10 87 6 90.151 iAUC (min 3 ng/mL) 21 6 6376 6286 50.095piride bypasses the glucose-dependence Epinephrine of insulin secretion, whereas the GLP-1 Fasting (ng/mL) 0.03 6 0.00 0.03 6 0.01 0.02 6 0.01 0.509 effects are strictly glucose dependent. Peak values (ng/mL) 0.11 6 0.04 0.10 6 0.04 0.17 6 0.05 0.099 However, since GLP-1 may enhance the 3 6 6 6 tAUC (min ng/mL) 8 2921330.677sensitivity of the KATP channels to ATP, it iAUC (min 3 ng/mL) 2 6 1†(2) 2 6 1†(2) 7 6 2†(0,1) 0.028 may still amplify the weaker signals gen- Data are mean values 6 SEM derived from a standardized liquid meal test at baseline (0) (after erated in HNF1A diabetes (33). In addi- a 1-week washout of blood glucose–lowering drugs) and at the end of each period of treatment tion, as mentioned earlier, GLP-1 may with liraglutide (1) and glimepiride (2). iAUC: incremental area under the curve. *P values are effect b-cell secretion downstream of derived from repeated-measurement ANOVA for variations between treatments and baseline. †Significant difference (P , 0.05) from the period given in parentheses (post hoc analysis). the KATP channels. These differential ef- fects of glimepiride and liraglutide also are reflected in the postprandial ISR re- sponse, which was more pronounced when in a stable condition, and no ad- during acute treatment with glibencla- during glimepiride treatment. justments to medicine were made mide and nateglinide in patients with GLP-1 has been shown to have dose- 2 months before inclusion. To reduce a HNF1A diabetes has previously been in- dependent inhibitory effects on gluca- potential carryover effect, treatment vestigated (11); after receiving a single gon secretion in patients with type 2 periods were preceded by a 1-week dose of test medicine immediately diabetes and in healthy individuals washout period. In addition, a rather before a test meal, in combination (18). Therefore, we expected reduced short treatment duration (6 weeks) with a mild cycling test (30 min), 6 of glucagon responses during treatment was chosen to minimize inadequate 15 patients experienced hypoglycemia with liraglutide. However, neither of compliance and patient withdrawal during glibenclamide treatment, whereas the treatments had any significant due to potential side effects. no events of hypoglycemia occurred effect on glucagon concentrations. SU acts by closing the KATP channels in during nateglinide treatment. In our tri- Whether patients with HNF1A defects b-cells, which causes depolarization al, we chose glimepiride because it is the have an altered a-cell function remains with subsequent influx of calcium and most commonly prescribed glucose- unknown. We previously showed that insulin secretion. Because of the specific lowering drug for patients with HNF1A patients with HNF1A diabetes suppress HNF1A b-cell defect reducing glucose diabetes. The glimepiride treatment al- glucagon normally following intravenous metabolism and ATP production, com- gorithm may have been too aggressive glucose but have an inappropriate hy- bined with a high sensitivity to SU during the study, since many patients perglucagonemic response to oral glu- (4,9,10), patients with HNF1A diabetes ended at a higher dose than they started cose (34), similar to patients with type treated with these drugs often are with at inclusion (Table 1). Since the 2 diabetes (35,36). prone to hypoglycemia (4,11). In addi- included patients were young and had No difference in gastric emptying was tion, preclinical studies indicated that no complications, target HbA1c was seen with any of the treatments. This SU therapy may lead to an accelerated 6.5% (48 mmol/mol) or less. This may can be due to the rather crude measure- loss of b-cell function and/or b-cell explain the majority of the hypoglyce- ment of gastric emptying using acet- mass, which may lead to treatment fail- mic events, but, clearly, some patients aminophen (in contrast to more exact ure (26,27). The risk of hypoglycemia are more prone to hypoglycemia than methods such as scintigraphy), to the 1804 GLP-1R Agonist vs. Sulfonylurea in MODY3 Diabetes Care Volume 37, July 2014

limited number of patients, or simply for patients with HNF1A diabetes to ob- the manuscript. T.H. designed the trial, recruited because of a declining effect of GLP- tain acceptable glycemic regulation MODY patients, and reviewed and edited the 1RAs on gastric emptying with time with a low risk of hypoglycemia and manuscript. O.P. recruited MODY patients and reviewed and edited the manuscript. J.F. ana- because of receptor desensitization or any other side effects (9,10,16). In con- lyzed plasma for catecholamines and reviewed tachyphylaxis (37–39). Furthermore, no clusion, GLP-1RAs may have a place in the manuscript. J.J.H. analyzed plasma for incre- previous reports have indicated differen- the treatment of patients with HNF1A tin hormones and glucagon and reviewed and ces in gastric emptying in patients with diabetes, especially when hypoglycemia edited the manuscript. F.K.K. and T.V. designed the trial and reviewed and edited the manu- HNF1A diabetes compared with healthy is a problem. script. S.H.Ø. is the guarantor of this work and, control subjects (25,34). as such, had full access to all the data in the trial No previous controlled studies pro- and takes responsibility for the integrity of the data and the accuracy of the data analysis. spectively examined the effect of GLP- Acknowledgments. The authors thank all Parts of this study were 1RAs in patients with HNF1A diabetes. participants for spending time on this project, Prior Presentation. presented at the 74th Scientific Sessions of the fi and they are grateful for expert technical The ndings in our trial are, however, American Diabetes Association, San Francisco, assistance from Jytte Purtoft, Nina Kjeldsen, consistent with recent case studies re- CA, 13–17 June 2014. fi and Sisse Schmidt, Diabetes Research Divi- porting bene cial effects of dipeptidyl sion, Gentofte Hospital, Denmark; Lene peptidase-4 inhibitors in patients with Albæk, Department of Biomedical Sciences, References HNF1A diabetes when combined with University of Copenhagen, Denmark; and 1. Andersen G, Hansen T, Pedersen O. Genetics other oral glucose-lowering drugs Ulla Kjærulff-Hansen, Department of Medi- of common forms of glycaemia with pathologi- (14,15) or with liraglutide as adjunct cine, Herlev Hospital, Denmark. The authors cal impact on vascular biology: are we on the thank Louise Vedtofte, Diabetes Research right track? Curr Mol Med 2005;5:261–274 therapy to SU and basal insulin (16). Center, Gentofte Hospital, Denmark, for 2. Johansen A, Ek J, Mortensen HB, Pedersen O, Whether monotherapy with GLP-1RA is proofreading the manuscript. Finally, the au- Hansen T. Half of clinically defined maturity- sufficiently effective to maintain an ac- thors are grateful for the cooperation of monitor onset diabetes of the young patients in Den- ceptable long-term glycemic regulation Stine Hovgaard, the GCP unit of Copenhagen mark do not have mutations in HNF4A, GCK, in patients with HNF1A diabetes is not University, Denmark. and TCF1. J Clin Endocrinol Metab 2005;90: Funding and Duality of Interest. The trial 4607–4614 clear from our trial. Because of the dif- was supported by Novo Nordisk A/S, which 3. Hansen SK, Parrizas´ M, Jensen ML, et al. Ge- ferent modes of action, a combination sponsored the liraglutide and the placebo pens, netic evidence that HNF-1alpha-dependent therapy using low or submaximal doses and by grants from The Augustinus Foundation transcriptional control of HNF-4alpha is essen- of SU (e.g., 0.5 mg of glimepiride once and The Aase og Ejnar Danielsen Foundation. The tial for human pancreatic function. Novo Nordisk Foundation Center for Basic Meta- – daily) and low or submaximal doses of J Clin Invest 2002;110:827 833 bolic Research is an independent Research Center 4. Pearson ER, Starkey BJ, Powell RJ, Gribble GLP-1RA (e.g., 0.6 mg liraglutide once at the University of Copenhagen and is partially FM, Clark PM, Hattersley AT. Genetic cause of daily) in patients with HNF1A diabetes funded by an unrestricted donation from the hyperglycaemia and response to treatment in might be an interesting option to ex- Novo Nordisk Foundation (http://metabol.ku.dk/). diabetes. Lancet 2003;362:1275–1281. plore further. This combination is based S.H.Ø. and J.I.B. have served on the speaker 5. McCarthy MI, Hattersley AT. Learning from on the hypothesis that SUs will effec- bureau for Merck, Sharp & Dohme. O.P. holds molecular genetics: novel insights arising from stocks in Novo Nordisk. J.F. has served on scien- the definition of genes for monogenic and type 2 tively close KATP channels, thereby syn- tific advisory panels for Sanofi, Novo Nordisk, diabetes. Diabetes 2008;57:2889–2898 ergizing with the effects of GLP-1RA, and Otsuka and has served as a consultant to 6. Pearson ER, Velho G, Clark P, et al. Beta-cell resulting in enhanced b-cell function Otsuka and Novo Nordisk. J.J.H. has served on genes and diabetes: quantitative and qualitative in a glucose-dependent fashion and low- speaker bureaus for Novo Nordisk, Merck, Sharp differences in the pathophysiology of hepatic & Dohme, and GlaxoSmithKline; has served as nuclear factor-1alpha and glucokinase muta- ering PG, with a reduced risk of hypogly- consultant for Novartis Pharmaceuticals, Novo tions. Diabetes 2001;50(Suppl 1):S101–S107 cemia. Many patients with HNF1A Nordisk, Merck, Sharp & Dohme, and Roche; 7. Møller AM, Dalgaard LT, Pociot F, Nerup J, diabetes are well treated with SU mono- and has received research support from Novo Hansen T, Pedersen O. Mutations in the hepa- therapy, but GLP-1RA monotherapy Nordisk and Merck, Sharp & Dohme. F.K.K. has tocyte nuclear factor-1alpha gene in Caucasian fi fi could be considered in patients who served on scienti c advisory panels for Bristol- families originally classi ed as having Type I di- Myers Squibb/AstraZeneca, Eli Lilly, Sanofi,and abetes. Diabetologia 1998;41:1528–1531 are particularly prone to hypoglycemia Zealand Pharma; has served as a consultant to 8. Boyd AE 3rd. The role of ion channels in insulin or are gaining weight. Patients with AstraZeneca, Gilead Sciences, Ono Pharmaceuti- secretion. J Cell Biochem 1992;48:235–241 HNF1A diabetes are known to have a cals, and Zealand Pharma; and has received re- 9. Søvik O, Njølstad P, Følling I, Sagen J, continuous loss of b-cells and b-cell search support from Sanofi.T.V.hasservedon Cockburn BN, Bell GI. Hyperexcitability to sul- scientific advisory panels for AstraZeneca, Boeh- phonylurea in MODY3. Diabetologia 1998;41: function (6), and GLP-1RAs are known – b ringer Ingelheim Pharmaceuticals, Eli Lilly and 607 608 to reduce -cell apoptosis in preclinical Company, GI Dynamics Inc., Novo Nordisk, Merck, 10. Pearson ER, Liddell WG, Shepherd M, settings (40); therefore treatment with Sharp & Dohme, Bristol-Myers Squibb, Sanofi, Corrall RJ, Hattersley AT. Sensitivity to sulpho- GLP-1RAs might slow the rate of b-cell and Takeda; has served as a consultant to Astra- nylureas in patients with hepatocyte nuclear loss in HNF1A diabetes. Zeneca, Boehringer Ingelheim Pharmaceuticals, Eli factor-1alpha gene mutations: evidence for When considering GLP-1RAs as a po- Lilly and Company, Novo Nordisk, Merck, Sharp & pharmacogenetics in diabetes. Diabet Med Dohme, Bristol-Myers Squibb, Sanofi, Novartis, 2000;17:543–545 tential treatment in patients with Zealand Pharma, and Takeda; and has received 11. Tuomi T, Honkanen EH, Isomaa B, Sarelin L, HNF1A diabetes, the glucose-lowering research support from Novo Nordisk. No other Groop LC. Improved prandial glucose control effects, side effects, and the method potential conflicts of interest relevant to this arti- with lower risk of hypoglycemia with nategli- of administration (oral vs. injection) as clewerereported. nide than with glibenclamide in patients with Author Contributions. S.H.Ø. designed the tri- maturity-onset diabetes of the young type 3. well as the cost of the drug must always al, performed all experiments, researched the Diabetes Care 2006;29:189–194 be considered for each individual pa- data, and wrote the manuscript. J.I.B. performed 12. Vilsbøll T, Krarup T, Madsbad S, Holst JJ. tient. Individualized therapy is crucial the statistical analyses and reviewed and edited Both GLP-1 and GIP are insulinotropic at basal care.diabetesjournals.org Østoft and Associates 1805

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