danaparoid sodium lowers proteinuria in diabetic nephropathy

7
Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy JOHAN W. VAN DER PIJL,* FOKKO J. VAN DER WOUDE,* PETRONELLA H. L. M. GEELHOEDDUIJVESTIJN,t MARIJKE FROLICH, FELIX J. M. VAN DER MEER, HERMAN H. P.J. LEMKES,” and LEENDERT A. VAN ES,* *Department of Nephrology, Leiden University Hospital, P0 Box 9600, 2300 RC Leiden, The Netherlands; tDepartment of Internal Medicine, Den Haag, The Netherlands; *Department of Clinical Chemistry, Leiden University Hospital, Leiden, The Netherlands; Department of Hematology, Leiden University Hospital, Leiden, The Netherlands; ‘Department of Endocrinology, Leiden University Hospital, Leiden, The Netherlands. Abstract. Diabetic nephropathy is a progressive renal disease with thickening of the gbomerular basement membrane and mesangial expansion and proliferation as histological hall- marks. The presence of the glycosaminoglycan side chains of heparan sulfate proteoglycan, an important constituent of the glomerular basement membrane, is decreased in diabetic ne- phropathy proportionally to the degree of proteinuria. Danap- aroid sodium is a mixture of sulfated glycosaminoglycans consisting mainly of heparan sulfate. The study presented here involved performing a randomized placebo-controlled cross- over study with danaparoid sodium in diabetic patients with overt proteinuria. The aim of the study was to evaluate the effect on proteinuria and safety/tolerability. Nine patients com- pleted the study, without major side effects; the crossover study consisted of two 6-wk periods of treatment with 750 anti-Xa units danaparoid sodium subcutaneously once-daily or placebo. Following danaparoid sodium, significant declines of both albuminuria and proteinuria were found. After danaparoid sodium, the albumin excretion ratio standardized for urinary creatinine reduced with 17% in comparison with an increase of 23% after placebo (95% confidence interval of the difference, -75.9-3.9%; P = 0.03). The percentage change of the urinary protein excretion corrected for urinary creatinine differed at 8 wk significantly between both treatment arms (P 0.001). Additional parameters for safety as hematobogical, hemostasis, biochemical parameters, and fundusphotography did not show any clinically significant difference for both groups. Only two patients had minor skin hematomas at the injection site while using danaparoid sodium. In conclusion, the supplementation was found to be feasible and was not associated with side effects. A significant decline of proteinuria was found. More prospective dose-finding and long-term studies must be performed to see whether danap- aroid sodium could not only induce a reduction of proteinuria but also halt the progression of renal disease. (J Am Soc Nephrol 8: 456-462, 1997) Diabetic nephropathy occurs in 30%-40% of patients with insulin-dependent diabetes melbitus (DM I). This type of renal disease progresses over time and is strongly related to a high mortality and morbidity rate (1-4). Proteoglycans and espe- cially the glycosaminoglycan (OAO) side chains of heparan sulfate (HS) are considered to be involved in the pathogenesis of diabetic nephropathy. Heparan sulfate is thought to be important for the gbomerular basement membrane (OBM) in terms of structure and function. It prevents clogging of the membrane and determines the sieving-function (5,6). HS is mainly responsible for the negative-charge barrier in the OBM (7), which is of relevance for preventing the passage of albu- mm through the capillary wall. HS may also slow down mes- angial expansion and proliferation (8-10). This is of utmost Received September 5, 1996 Accepted November 1 1, 1996 Correspondence to Dr. J.W. van der Pijl, Department of Nephrobogy, C3-P, 1 Leiden University Hospital, P0 Box 9600, 2300 RC Leiden, The Netherlands. l046-6673/0803-0456$03.00/0 Journal of the American Society of Nephrology Copyright (C) 1997 by the American Society of Nephrobogy importance because mesangial expansion and proliferation are both strongly correlated with decline of renal function (4,1 1). A reduced synthesis and sulfatation of heparan sulfate proteo- glycans by podocytes and mesangial cells, when cultured under high glucose conditions, has been reported (12,13). The key role of HS for the normal function of the OBM is illustrated by the following findings: removal of HS by hepa- rinitase (14) or shielding of HS by a monoclonal antibody (15) generates albuminuria in vivo. In type I diabetic patients with nephropathy, staining for heparan sulfate OAOs in the OBM is reduced in proportion to the amount of proteinuria (16,17). In the context of such a pivotal role of HS in diabetic nephropathy, several studies have investigated whether supple- mentation of sulfated glycosaminoglycans could be of any benefit. Indeed, the development of diabetic nephropathy could be prevented by giving glycosaminoglycans to rats with strep- tozotocin-induced diabetes meblitus (18). Several clinical stud- ies have reported preliminary results in type I diabetics with micro- and macroalbuminuria. Myrup et a!. found a reduction of microalbuminuria after treatment with low molecular weight heparin (LMWH) and with standard heparin (19). In mac-

Upload: buiminh

Post on 04-Feb-2017

225 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy

Danaparoid Sodium Lowers Proteinuria in Diabetic

Nephropathy

JOHAN W. VAN DER PIJL,* FOKKO J. VAN DER WOUDE,*

PETRONELLA H. L. M. GEELHOED�DUIJVESTIJN,t MARIJKE FROLICH,�

FELIX J. M. VAN DER MEER,� HERMAN H. P.J. LEMKES,” and

LEENDERT A. VAN ES,**Department of Nephrology, Leiden University Hospital, P0 Box 9600, 2300 RC Leiden, The Netherlands;tDepartment of Internal Medicine, Den Haag, The Netherlands; *Department of Clinical Chemistry, Leiden

University Hospital, Leiden, The Netherlands; �Department of Hematology, Leiden University Hospital,

Leiden, The Netherlands; ‘Department of Endocrinology, Leiden University Hospital, Leiden, The Netherlands.

Abstract. Diabetic nephropathy is a progressive renal disease

with thickening of the gbomerular basement membrane and

mesangial expansion and proliferation as histological hall-

marks. The presence of the glycosaminoglycan side chains of

heparan sulfate proteoglycan, an important constituent of the

glomerular basement membrane, is decreased in diabetic ne-

phropathy proportionally to the degree of proteinuria. Danap-

aroid sodium is a mixture of sulfated glycosaminoglycans

consisting mainly of heparan sulfate. The study presented here

involved performing a randomized placebo-controlled cross-

over study with danaparoid sodium in diabetic patients with

overt proteinuria. The aim of the study was to evaluate the

effect on proteinuria and safety/tolerability. Nine patients com-

pleted the study, without major side effects; the crossover

study consisted of two 6-wk periods of treatment with 750

anti-Xa units danaparoid sodium subcutaneously once-daily or

placebo. Following danaparoid sodium, significant declines of

both albuminuria and proteinuria were found. After danaparoid

sodium, the albumin excretion ratio standardized for urinary

creatinine reduced with 17% in comparison with an increase of

23% after placebo (95% confidence interval of the difference,

-75.9-3.9%; P = 0.03). The percentage change of the urinary

protein excretion corrected for urinary creatinine differed at 8

wk significantly between both treatment arms (P 0.001).

Additional parameters for safety as hematobogical, hemostasis,

biochemical parameters, and fundusphotography did not show

any clinically significant difference for both groups. Only two

patients had minor skin hematomas at the injection site while

using danaparoid sodium.

In conclusion, the supplementation was found to be feasible

and was not associated with side effects. A significant decline

of proteinuria was found. More prospective dose-finding and

long-term studies must be performed to see whether danap-

aroid sodium could not only induce a reduction of proteinuria

but also halt the progression of renal disease. (J Am Soc

Nephrol 8: 456-462, 1997)

Diabetic nephropathy occurs in 30%-40% of patients with

insulin-dependent diabetes melbitus (DM I). This type of renal

disease progresses over time and is strongly related to a high

mortality and morbidity rate (1-4). Proteoglycans and espe-

cially the glycosaminoglycan (OAO) side chains of heparan

sulfate (HS) are considered to be involved in the pathogenesis

of diabetic nephropathy. Heparan sulfate is thought to be

important for the gbomerular basement membrane (OBM) in

terms of structure and function. It prevents clogging of the

membrane and determines the sieving-function (5,6). HS is

mainly responsible for the negative-charge barrier in the OBM

(7), which is of relevance for preventing the passage of albu-

mm through the capillary wall. HS may also slow down mes-

angial expansion and proliferation (8-10). This is of utmost

Received September 5, 1996 Accepted November 1 1, 1996

Correspondence to Dr. J.W. van der Pijl, Department of Nephrobogy, C3-P, 1Leiden University Hospital, P0 Box 9600, 2300 RC Leiden, The Netherlands.

l046-6673/0803-0456$03.00/0

Journal of the American Society of Nephrology

Copyright (C) 1997 by the American Society of Nephrobogy

importance because mesangial expansion and proliferation are

both strongly correlated with decline of renal function (4,1 1).

A reduced synthesis and sulfatation of heparan sulfate proteo-

glycans by podocytes and mesangial cells, when cultured under

high glucose conditions, has been reported (12,13).

The key role of HS for the normal function of the OBM is

illustrated by the following findings: removal of HS by hepa-

rinitase (14) or shielding of HS by a monoclonal antibody (15)

generates albuminuria in vivo. In type I diabetic patients with

nephropathy, staining for heparan sulfate OAOs in the OBM is

reduced in proportion to the amount of proteinuria (16,17).

In the context of such a pivotal role of HS in diabetic

nephropathy, several studies have investigated whether supple-

mentation of sulfated glycosaminoglycans could be of any

benefit. Indeed, the development of diabetic nephropathy could

be prevented by giving glycosaminoglycans to rats with strep-

tozotocin-induced diabetes meblitus (18). Several clinical stud-

ies have reported preliminary results in type I diabetics with

micro- and macroalbuminuria. Myrup et a!. found a reduction

of microalbuminuria after treatment with low molecular weight

heparin (LMWH) and with standard heparin (19). In mac-

Page 2: Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy

Danaparoid Sodium and Proteinuria 457

roalbuminuric patients treated with enoxaparin (a LMWH), a

significant decline of the urinary albumin excretion rate (AER)

was found, but significance was not reached in comparison

with the placebo treated group (20).

Danaparoid sodium is a new, commercially available, hep-

armnoid. It is a mixture of sulfated OAOs, consisting mainly of

HS with a small subfraction, which is highly sulfated. It is used

both for the prevention and treatment of venous thromboem-

bolism, where it has been shown to be efficacious and rela-

lively safe. It functions by augmenting the inhibitory action of

antithrombin on activated clotting factors Xa and ha. The high

ratio of anti-Xa/anti-IIa activity is thought to be responsible for

a good efficacy/safety profile. It is seldom associated with

heparin-induced thrombocytopenia. Clearance takes place

mainly by the kidneys (21-23). Therefore, and because dan-

aparoid sodium consists to a large extent of heparan sulfate, we

decided to study the effect of danaparoid sodium on proteinuna

in type I diabetic patients.

Materials and MethodsDesign

The study was designed as a phase II, randomized, double-blind,

placebo-controlled, crossover study. The medical ethical committee of

the Leiden University Hospital had approved the protocol of the study,

and all patients gave informed consent. Eligible patients were ran-

domly allocated to one of the two treatment groups: 750 anti-Xa units

danaparoid sodium (Orgaran#{174}, NV Organon, Oss, the Netherlands),

subcutaneously (SC) administered once daily for 6 wk; a wash-out

period of at least 4 wk; placebo (saline with sulfite), SC administered

once-daily for 6 wk, or the same scheme in the opposite direction.

Medical and laboratory assessments were performed every 2 wk (0 =

baseline; 2, 4, 6, and 8 wk after start of the respective treatments).

Patients

The study population consisted of nine patients who had nephrop-

athy due to DBM and fulfilled the following selection criteria: they

had to be > 18 years old; they had to have insulin-dependent diabetes

mellitus type I (DM I) with macroabbuminuria (AER >300 mg/24 h)

because of diabetic nephropathy and not because of other renal

disease; and they had to give informed consent. The use of angiotensin

I converting enzyme (ACE)-inhibitors and other antihypertensive

medications was only allowed if given at a stable dosage at least 6 wk

prior to start of the study.

Patients complying with the inclusion criteria were eligible if none

of the following exclusion criteria were present: pregnancy or wish to

become pregnant; hemorrhagic diathesis; use of medications known to

interfere with hemostasis and/or platelet function; use of corticoste-

roids; uncontrolled hypertension; active proliferative retinopathy; his-

tory of heparin-induced thrombocytopenia; severe hepatic failure;

creatinine clearance of <40 mL/min; hypersensivity to sulfite.

Medication

Danaparoid sodium is a mixture of sulfated GAGs, consisting of

84% heparan sulfate (HS), 12% dermatan sulfate, and 4% chondroitin

sulfate isolated from porcine intestinal mucosa. It has an average

molecular of weight 4000-7000 d, a specific anti-Xa activity of

11.0-17.0 U/mg, and an anti-Xa/anti-IIa ratio of >22. The elimina-

tion half-life of anti-Xa activity is -25 h. The half-life time is only

affected by severe renal failure, as seen in patients on chronic hemo-

dialysis. The placebo had the same appearance as the danaparoid

sodium containing ampoubes; it contained isotonic sodium chloride

and sodium sulfite. Danaparoid sodium (0.6 ml, 750 anti-Xa units)

and the placebo were administered once-daily by subcutaneous (SC)

injection for 6 wk, followed by a wash-out period of at least 4 wk. The

patients were trained to self-administer the study medication in an

abdominal skinfold. The date and time of each injection was recorded

daily by the patient on a list and checked by the investigator at the end

of each treatment period, together with the number of returned unused

ampoules. Protamine-containing insulin preparations were not al-

bowed to be injected at the same site, and study medication was not

allowed to be mixed with insulin.

Efficacy Assessments

In diabetic nephropathy, both proteinuria and macroalbuminuria

are associated with a steady decline of renal function. Taking the

relative short duration of treatment into account, we decided to use

proteinuria and albuminuria as surrogate markers. These parameters

were expressed per mmol of creatinine to correct for incomplete

urinary collections. The main parameters for efficacy were urinary

albumin excretion rate (AER) and urinary protein excretion rate

(PER) corrected for urinary creatinine excretion rate. Therefore, total

protein, albumin, and creatinine contents in 2 X 24-h urine samples

(collected by the subject at home) were assessed. Baseline measure-

ments were taken before both treatment periods. At 0, 4, 6, and 8 wk,

AER, PER, and creatinine clearance were measured twice, and the

means were compared with baseline (0 wk).

Safety Assessments

A general medical history (including duration of patients’ DM I),

height, weight, blood pressure, and heart rate after 3 mm in sitting

position were taken, and a medical examination was performed.

Fundusphotography (including staging of observed retinopathy) was

performed before the inclusion and at the end of the study period.

Sodium, potassium, urea, creatinine, glucose, total protein, albumin,

serum glutamic oxaboacetic transaminase (SOOT), serum glutamic

pyruvic transaminase (SOPT), alkaline phosphatase, yGT, HbA �,

hemoglobin, hematocrit, leukocytes, thrombocytes, prothrombin time,

antithrombin III, activated partial thromboplastin time (APTE’), and

plasma anti-Xa activity were tested regularly as safety and tolerability

parameters.

Laboratory Assessments

Urinary albumin was assessed using immunonephebometry on an

autoanalyser (Array Protein system, Beckman Instruments, Brea, CA)

with specific antibodies. Urinary protein, serum sodium, potassium,

urea, creatinine, protein, albumin, SGOT, SGPT, alkaline phospha-

tase, and yGT levels were assessed on a Hitachi 747 or 91 1 autoanal-

yser (Boehnnger, Mannheim, Germany). The Technicon H-l system

(Bayer Diagnostics, MUnchen, Germany) was used for the analysis of

hematobogical parameters. Prothrombin time was determined using

the Thromborel S reagent (Behringwerke AG, Marburg, Germany),

amd APTT was determined using the Cephotest reagent (Nyegaard,

Oslo, Norway), both on an Electra 1000C coagulometer (MLA, Pleas-

antville, NY). Antithrombin and anti-Xa activity were assessed on an

ACL 200 (Instrumentation Laboratory, Milan, Italy) with Coamatic

Antithrombin and Coatest LMWHeparin as reagents (Chromogenix,

M#{246}lndal, Sweden). HbAIC was assessed on high-performance liquid

chromatography (HPLC) after hemolysis.

Page 3: Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy

458 Journal of the American Society of Nephrology

Table 1. Demographic dataa

Patientno.

Age(y)

Sex DM(y)

ACEi BMI(kg/rn2)

MAP(mmHg)

HbA1C(%)

AER(mg/24 h)

AER/Creat(mg/mmol)

PER/Creat(mg/mmol)

CrCb(mi/mm)

1 43 M 20 No 32.8 99 8.3 1000 64 90 119

2 52 M 28 Yes 29.8 100 7.5 1032 91 122 70

3 32 F 20 Yes 22.4 107 7.6 3044 250 368 62

4 33 M 24 No 27.1 107 7.4 968 63 97 127

5 35 M 31 No 27.6 113 10.8 715 95 103 54

6 44 M 25 Yes 28.7 103 7.7 912 64 86 141

7 29 M 16 No 22.1 105 7.4 670 52 72 68

8 29 M 26 Yes 23.9 103 7.4 258 21 35 96

9 25 M 14 No 28.7 107 9.8 403 46 70 79

a DM, diabetes mellitus type I; ACEi, yes denotes the use of ACE inhibitor, and no denotes no ACE inhibition; BMI, body mass index;

BP, blood pressure; MAP, mean arterial pressure; AER/creat, urinary albumin excretion rate standardized for urinary creatinine excretionrate; PER/creat, urinary protein excretion rate standardized for urinary creatinine excretion rate; CrCl, creatinine clearance.

Statistical Analyses

The mean change of the primary and secondary parameters duringthe two treatment periods were analyzed using a mixed-model anal-

ysis of variance (ANOVA), with random patient factor to account for

the correlations between the repeated measurement, and fixed treat-ment and time factors. In addition, single degree-of-freedom (paired t)

tests were used to evaluate differences between and within the two

treatment periods. Because the distribution of the primary parameters

was extremely skewed, a logarithmic transformation was applied. �values (relative change) for AERlcreat and PER/creat were calculated

as follows:

(y-x/x)* 100% = 6, where y is the nth week value for AERicreat or

PER/creat and x is the 0 week value. Significance was accepted at the

P-value level of 0.05. The calculations were performed with the SPSS

package release 6.0 for Windows.

ResultsPatients

Nine patients were enrolled in the study, and all completed

both crossover treatment periods. Prior to the study, two pa-

tients were treated with lasercoagulation for proliferative reti-

nopathy for ophthalmologic reasons only. Demographic data

and characteristics are given in Table 1 . In general, the HbAlc

reflected an acceptable metabolic control of the diabetes. In

contrast, the blood pressure was rather high for these patients.

The albuminuna and proteinuria ranged from borderline

“overt” (patient 8) to proteinuna in the nephrotic range (patient

3). Four patients were on ACE-inhibitors, and one of these also

used amlodipine. Table 2 shows the primary parameters per

group and treatment, Tables 3a and 3b show individual results.

HbAlc was 8.5% before the treatment period with danap-

aroid sodium and 8.3% before placebo (P = 0.4). No major

changes were made for the insulin dosage during both periods.

The baseline values of the MAP did not differ between the two

groups (103 mmHg and 105 mmHg; P = 0.3). No major

adverse events occurred. One patient needed antibiotic treat-

ment during the placebo period because of sinusitis without

fever. Subcutaneous injections were performed once daily dur-

Table 2. Creatinine clearance, blood pressure, AER/creatinine, and PER/creatinine before and after treatment with placebo

and danaparoid sodiuma

Danaparoid Sodium Placebo

0 wk 8 wk P value 0 wk 8 wk P value

CrC1 (mi/mm) 102.9

(75.5-1 30.4)

96.9

(68.4-1 25.4)

0.37 90.4

(74.0-106.8)

100.5

(69.7-131.4)

0.20

MAP (mm Hg)

AERlcreat (mg/mmol)

PER/creat (mg/mmol)

103.0

(100.6-105.4)

74.8

(42.7-1 3 1 .2)

111.0

(65.5-1 87.9)

102.2

(98.5-106.0)

60.6

(33. 1-1 10.9)

89.3

(5 1 .9-1 53.8)

0.68

0.03

0.008

105.4

(98.9-1 1 1.8)

64.8

(36.7-1 14.7)

87.0

(5 1 .9-146.0)

98.5

(92.7-104)

75.8

(37.2-154.3)

110.6

(57.4-213.1)

0.26

0.18

0.12

a All values are expressed as mean and (95% confidence interval of the mean), except for AER/creat and PER/creat, which are

expressed as geometric mean (antilog 95% CI). CrCb, creatinine clearance; MAP, mean arterial pressure; AER/creat, urinary albumin

excretion rate standardized for urinary creatinine excretion rate; PER/creat, urinary protein excretion rate standardized for urinarycreatinine excretion rate. P values are obtained with paired t tests (within each treatment block).

Page 4: Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy

150.

100.

50.

8)

‘3

a)0)CCs

‘3

Tyvy,

AA�&

-50.

-100.

-150.

Danaparoid Sodium and Proteinuria 459

Table 3a. Individual results: AER/creat

. Danaparoid SodiumPatient R

No. � wk 4 (�) wk 6 (6) wk

Placebo

8 (3) wk 0 wk 4 (�) wk 6 (�) wk 8 (�) wk

1 D 64 83(+29%) 75(+17%) 53(-18%) 78 63(-20%) 77(-l%) 77(-l%)

2 P 133 1l4(-14%) lll(-l7%) 107(-l9%) 90 74(-19%) 138(+52%) l24(+36%)

3 D 250 205(-l8%) 238(-5%) 217(-13%) 280 292(+4%) 223(-20%) 337(+2l%)

4 P 75 78(+4%) 90(+l9%) 77(+3%) 63 87(+37%) 75(+18%) 73(+l5%)

5 P 144 b86(+29%) l29(-ll%) l13(-22%) 96 132(+38%) l36(+42%) ll8(+24%)

6 D 64 33(-49%) 42(-35%) 29(-54%) 39 44(+l4%) 55(+4l%) 47 (+21%)

7 D 52 56(+8%) 43(-l8%) 54(+3%) 60 38(-36%) 43(-28%) 42 (-30%)

8 P 21 l9(-lb%) 22(+4%) 15(-26%) 21 24(+13%) l3(-40%) 20(-6%)

9 D 46 26(-44%) 40(-l2%) 43(-7%) 34 nd 72(+112%) 78(+l27%)

Table 3b. Individual results: PER/creat�’

. Danaparoid SodiumPatient R

No. � wk 4 (�) wk 6 (�) wk

Placebo

8 (t�) wk 0 wk 4 (�) wk 6 (�) wk 8 (�) wk

1 D 90 l31(+46%) l0l(+l3%) 97(+8%) 119 105(-12%) l23(+3%) l23(+3%)

2 P 178 l9l(+8%) l52(-15%) l32(-26%) 122 9l(-26%) l7l(+40%) l63(+33%)

3 D 368 302(-l8%) 347(-6%) 323(-12%) 365 526(+44%) 351 (-4%) 459(+26%)

4 P 127 126(-l%) l30(+2%) l08(-l5%) 97 l30(+35%) llO(+14%) ll2(+l6%)

5 P 211 235(+ll%) l90(-bO%) l40(-34%) 52 195(+277%) l75(+237%) 15l(+l92%)

6 D 86 64(-25%) 62(-27%) 52(-40%) 62 73(+l8%) 80(+29%) 79(+28%)

7 D 72 67(-6%) 63(-l2%) 69(-4%) 83 50(-40%) 58(-29%) 52 (-37%)

8 P 38 34(-ll%) 39(+2%) 27(-29%) 35 43(+2b%) 29(-l9%) 35(-2%)

9 D 70 37(-48%) 58(-l7%) 60(-14%) 60 nd 89(+48%) l24(+105%)

a Note. � values (relative change) for AER/creat and PER/creat were calculated as follows: (y - x/x*lOO%) = 5, where y is the net’

week value for AER/creat or PER/creat and x is the 0 wk value. R (randomization) denotes whether danaparoid sodium (D) or placebo (P)was the first treatment block; AER/creat (and PER/creat), urinary albumin (protein) excretion rate standardized for urinary creatinine

excretion rate; nd, no data.

ing both treatment periods without clinically important side

effects. In two patients, small skin hematomas at the injection

site occurred during treatment with danaparoid sodium. Ac-

cording to the number of returned unused ampoules and the

compliance checklist, the compliance was excellent; only two

patients skipped one injection. The duration of treatment was

42 days (median) for danaparoid sodium (range, 41-47) and 42

days (range, 41-45) for the placebo treatment.

Efficacy Parameters

A significant decline of both albuminuria and proteinuria

was found after treatment with danaparoid sodium compared

with baseline and with the placebo treatment. Figure 1 shows

the percentage reduction of albuminuria for both groups. Com-

pared with baseline, the AER/creatinine at the end of the

treatment period was - I 7% for the danaparoid sodium group

and +23% for the placebo group (95% confidence interval (CI)

ofthe difference -75.9-3.9%, P = 0.03). Even after omitting

the outlier of 126% increase during placebo, a significant

difference was found (P <0.05). The protein excretion rate

standardized for creatinine excretion showed a decrease of

18% in the danaparoid sodium group, whereas an increase of

danaparoid placebo

Figure 1. A scatter diagram showing the percentage difference (�) of

the albumin excretion rate standardized for the urinary creatinine

excretion comparing 8-wk with baseline in both treatment arms. �

values for AER/creat and PER/creat were calculated as follows: (y -

x/x)*l00% = & where y is the 8-wk value for AER/creat and x is the

0-wk value. The difference is significant (P < 0.03).

40% was seen in the placebo group (95% CI of the difference

- 1 15.8-1.0%, P <0.05). Figure 2 shows the mean percentage

change of the urinary protein/creatinine ratios during both

treatment regimens. The difference of the overall change pat-

tern in both treatment groups was highly significant (P =

Page 5: Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy

‘I)>

�w

� 25

0).O 0CCs

U -25

weeks

Figure 2. The percentage change (�) of the protein excretion rate

standardized for urinary creatinine excretion from baseline in bothtreatment arms. The overall difference is P = 0.001 . The relative

change at the respective timepoints 4, 6, and 8 wk in comparison withbaseline was as follows: P = 0.22 (95% CI of the difference -118.3-

29.2%), P = 0.13 (95% CI ofthe difference - 100.1-14.1%), and P =

0.02 (95% CI of the difference - 108.3-9.5%). The bars are standard

errors of the mean. Triangles denote placebo, and squares denote thedanaparoid sodium treatment.

0.001). The relative change at the respective timepoints of 4, 6,

and 8 wk in comparison with baseline was P = 0.41 (95% CI

of the difference -39.6-17.2%), P = 0.15 (95% CI of the

difference -61.7-10.1%), and P = 0.02 (95% CI of the

difference -73.2-6.6%). Similar results were found for the

overall change pattern for urinary albumin/creatinine ratios

(P = 0.002). Especially Figure 2 demonstrates that the effects

on proteinuria (and albuminuria-figure not shown) become

more apparent after 2 months than after the first month. A

small and not significant difference was found comparing the

pre- and post-treatment values for the MAP: after placebo, a

decline of 4.7% was found, and after danaparoid sodium, a

decline of 0.9% was found (P = 0.4). Creatinine clearances did

not differ significantly, either: -5. 1% after danaparoid sodium

and + 16.6% after placebo (P = 0.2). Subanalysis respective-

lyof the use of ACE inhibition and the order of treatment

(danaparoid sodium/placebo or placebo/danaparoid sodium)

was not possible due to low figures

Safety Parameters

No changes in visual acuity occurred during treatment. Fun-

dusphotography did not show hemorrhages, and no progression

of retinopathy was found in any of the patients. Anti-Xa values

were detectable only once in two patients (respectively, 0.12

and 0.10 U/mL; bower limit of detection <0.10 U/mL); this

was not accompanied by any change of coagulation test results

(APTT). No changes occurred for hematological parameters,

and values within each patient during both treatment periods

remained about the same for hemoglobin, leukocytes and

thrombocytes. Liver enzymes (including alkaline phosphatase)

did not change, either.

DiscussionOptimizing the treatment of DM I with the goal of slowing

down the progression of vascular and renal damage has been

the subject of many studies. In the past , intensified insulin

treatment, antihypertensive treatment in general, and especially

ACE inhibition have been shown to slow the progression of

diabetic nephropathy (24-27). We decided to evaluate in a

clinical setting the applicability of proteoglycans as an addi-

tional treatment modality. All of our patients had macroabbu-

minuria, and they had, therefore, passed the point of revers-

ibility of this specific renal disease. The Danish group has

already shown a benefit of LMWH and heparin for microalbu-

minuric patients (19). A previous study with enoxaparin in

macroalbuminuric patients from our unit failed to demonstrate

a statistically significant difference between placebo and

LMWH (20), although a significant decrease in proteinuria was

seen in the treated group when pretreatment values were taken

into consideration. The difference between placebo and

LMWH may not have been found because of the small number

of patients studied and the short duration of the study. In the

study presented here, we observed a clear reduction for the

AER and PER after treatment with danaparoid sodium for 6

wk. Only one woman participated in this study (with a good

response on therapy); we acknowledge more women need to be

studied before our results may be applied to both sexes. Al-

though not clinically or statistically significant, MAP showed a

trend to decline in the placebo group. This might be explained

by regression to the mean. We found no effects on blood

pressure during danaparoid sodium treatment.

The most important result of our study is that the goal to

reduce AER and PER by HS therapy may be feasible. The

favorable chemical and clinical profile of danaparoid sodium in

comparison to heparin and LMWHs made us decide to study

this medication (28). Heparmn-induced thrombocytopenia and

thrombosis is a feared clinical picture with a dismal outcome.

Only danaparoid sodium in comparison to heparin and LM-

WHs is associated with a very low incidence of this compli-

cation (28). Osteoporosis is another drawback associated with

long-term heparin use. Limited experience with LMWHs

showed a more favorable outcome in this respect (29,30).

Heparins and HS both exert anti-inflammatory actions as

well as antiproliferative effects. An excellent short review on

this topic was recently published by Wardle (3 1). Heparin

prevents basic fibroblast growth factor induced proliferation

and may also stop smooth muscle cell proliferation by releas-

ing transforming growth factor �3 from its binding protein

(32,33). It also inhibits the synthesis and release of endothelin-I

by endothelial cells (34). The negative charge at the N position

is thought to be required for the antiproliferative action (35).

Danaparoid sodium is not a LMWH but a heparinoid. It

consists of 84% HS. Only a small fraction (4%-5%) of this HS

is highly sulfated and is considered to be important for the

anti-Xa activity. The fraction of HS with a low affinity for

antithrombin III does not affect coagulation factors Xa and lIa

but contributes substantially to the antithrombotic activity,

probably through an effect on endothelial cells (23). The dose-

related response to danaparoid sodium remains gradual and

linear over a wide range, which may contribute to its safety. It

has a 100% bioavailibility after subcutaneous administration.

Studies in humans have been using heparin or LMWH. We

thought that danaparoid sodium could have a more favorable

460 Journal of the American Society of Nephrology

Page 6: Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy

Danaparoid Sodium and Proteinuria 461

benefit/risk profile in case of long-term prescription in com-

parison to LMWH. The theoretical arguments of a bower sub-

fate content and, hence, less effect on proteinuria were not

validated by our findings. Whether only the 4%-5% high-

affinity HS fraction has been of relevance for the antiprotein-

uric effect or the low sulfated fraction has been of a comple-

mentary benefit has yet to be established. Based on the half-life

time of danaparoid sodium (25 h for the anti-Xa activity), a

4-wk wash-out period was thought-prior to the study-to be

reasonable and long enough. The results and especially the

increase of proteinuria during the placebo period suggest in

retrospect that this increase might, in part, be explained by a

carry-over effect. However, in the Danish study, the LMWH

and the placebo groups also showed 3 months after the study an

increase of albuminuria of 30% and 125% relative change,

respectively (19). For further crossover studies, not only the

drug half-life time, but also an additional lag-time because of

the mediated effects of danaparoid sodium should be taken in

consideration to prevent this putative confounding effect.

Our results are in agreement with previously reported results

of proteoglycans on proteinuria in diabetic nephropathy

(19,20). This short-term study demonstrates, as already seen in

animal models, that proteoglycans can exert a reversible effect

also at a late stage of nephropathy ( 18). Because we have not

taken any renal biopsies to substantiate the level of changes on

histological examinations, we can only hypothesize about the

mechanism of action. As danaparoid sodium is mainly cleared

by the kidneys, both replacement of “faulty” HS molecules in

the OBM as well, as a beneficial effect on smooth muscle cell

and mesangial cell proliferation, could have accounted for the

clinically observed effects. In previous studies using sulfated

glycosaminoglycans, no differences were found for gbomerular

filtration rate, renal plasma flow, and filtration fraction

(19,20,36). This suggests that the antiproteinuric effect of HS

is not related to altered renal hemodynamics.

In conclusion, the once-daily SC administration of 750 an-

ti-Xa u of danaparoid sodium resulted in a significant reduction

of proteinuria in patients with overt diabetic nephropathy.

More clinical studies are needed to confirm and extend our

findings. A dose-finding study should also be performed. It is

obvious that only long-term studies will prove that the reduc-

tion of proteinuria will be associated with a slower decline or

even maintenance of renal function in diabetic nephropathy.

AcknowledgmentsIan Egberts (NV Organon, Oss, the Netherlands) has contributed

with fruitful discussions and provided us with medication and pla-

cebo. We are indebted to Koos Zwinderman (Department of Medical

Statistics, University of Leiden, The Netherlands), who assisted in the

statistical analysis.

References1. Andersen AR, Christiansen IS, Andersen 1K, Kreiner S. Deckert

T: Diabetic nephropathy in type I (insulin-dependent) diabetes:

An epidemiobogical study. Diabetologia 25: 496-501, 1983

2. Mogensen CE, Christensen CK, Vittinghus E: The stages in

diabetic renal disease: With emphasis on the stage of incipient

diabetic nephropathy. Diabetes 32: 564-578, 1983

3. Deckert T, Feldt-Rasmussen B, Borch-lohnsen K, Kofoed-

Enevoldsen A: Abbuminuria reflects widespread vascular dam-

age: The Steno hypothesis. Diabetologia 32: 219-226, 1989

4. Osterby R, Gundersen HI, Horlyck A, Kroustrup IP, Nyberg 0,Westberg 0: Diabetic gbomerubopathy: Structural characteristics

of the early and advanced stages. Diabetes 32: 579-582, 1983

5. Kanwar YS, Rosenzweig I, lakubowski ML: Distribution of denovo synthesized sulfated glycosaminoglycans in the glomerular

basement membrane and the mesangial matrix. Lab Invest 49:

216-225, 1983

6. Kanwar YS, Rosenzweig U: Clogging of the gbomerubar base-

ment membrane. J Cell Biol 93: 489-494, 1982

7. Kanwar YS, Hascall VC, Farquhar MG: Partial characterization

of synthesized proteoglycans isolated from the glomerular base-

ment membrane. J Cell Biol 90: 527-532, 19818. Groggel OC, Marinides ON, Hovingh P, Hammond E, Linker A:

Inhibition of rat mesangiab cell growth by heparan sulfate. Am J

Physiol 258: F259-F260, 1990

9. Striker LI, Peten EP, Elliot SI, Doi T, Striker GE: Mesangiab cell

turnover: Effect of heparin and peptide growth factors. Lab

lnvest 64: 446-456, 1991

10. Coffey AK, Karnovsky Ml: Heparin inhibits mesangial cell

proliferation in habu-venom-induced gbomerular injury. Am J

Pathol 120: 248-255, 1985

1 1. Mauer SM, Steffes MW, Ellis EN, Sutherland DES, Brown DM,

Ooetz FC: Structural-functional relationships in diabetic ne-phropathy. J Clin Invest 74: 1 143-1 155, 1984

12. van Det NF, van den Born IT, Tamsma IT, Verhagen NAM, van

den Heuvel LPWI, Berden IHM, Bruijn JA, Daha MR. van der

Woude Fl: Proteoglycan production by human gbomerular vis-

ceral epithebial cells and mesangial cells in vitro. Biochem J 307:

759-768, 1995

13. van Det NF, van den Born I, Tamsma IT, Verhagen NAM,

Berden IHM, Bruijn IA, Daha MR. van der Woude Fl: Effects of

high glucose on the production of heparan sulfate proteoglycan

by human mesangial and gbomerular visceral epithebiab cells in

vitro. Kidney Int 49: 1079-1089, 1996

14. Rosenzweig LI, Kanwar YS: Removal of sulfated (heparan sulfate)

or nonsulfated (hyaluronic acid) glycosaminoglycans results in in-

creased permeability of the gbomerular basement membrane to ‘

bovine serum albumin. Lab Invest 47: 177-184, 1982

15. van den Born I, van den Heuvel LP, Bakker MA, Veerkamp IH,

Assmann IU, Berden IH: A monocbonab antibody against OBM

heparan sulfate induces an acute selective proteinuria in rats.

Kidney mt 4 1: 115-1 23, 1992

16. Vernier RL, Steffes MW, Sisson-Ross 5, Mauer SM: Heparan

sulfate proteoglycan in the gbomerubar basement membrane in

type I diabetes mellitus. Kidney mt 41: 1070-1080, 1992

17. Tamsma IT, van den Born I, Bruijn IA, Assmann KJM, Weening

IJ, Berden IHM, Wieslander I, Schrama E, Hermans I,

Veerkamp IH, Lemkes HHPJ, van der Woude Fl: Expression ofglomerular extracelbular matrix components in human nephrop-

athy: Decrease of heparan sulphate in the gbomerular basement

membrane. Diabetologia 37: 313-320, 1994

18. Oambaro 0, Cavazzana AO, Luzzi P, Piccoli A, Borsatti A,

Crepaldi 0, Marchi E, Venturini AP, Baggio B: Glycosamino-

glycans prevent morphological renal alterations and albuminuria

in diabetic rats. Kidney mt 42: 285-291, 1992

19. Myrup B, Hansen PM, Iensen T, Kofoed-Enevoldsen A, Feldt-

Rasmussen B, Gram I, KIuft C, Iespersen I, Deckert T: Effect of

Page 7: Danaparoid Sodium Lowers Proteinuria in Diabetic Nephropathy

462 Journal of the American Society of Nephrology

low-dose heparmn on urinary albumin excretion in insulin-depen-

dent diabetes mellitus. Lancet 345: 421-422, 1995

20. Tamsma IT, van der Woude FJ, Lemkes HHPI: Effect of sub-phated glycosaminoglycans on albumiuria in patients with overt

(type I) nephropathy. Nephrol Dial Transplant 1 1 : 182-185,

1996

21. de Valk HW, Banga ID, Wester 1W, Brouwer CB, van Hessen

MW, Meuwissen 01, Hart HC, Sixma II, Nieuwenhuis HK:Comparing subcutaneous danaparoid with intravenous unfrac-

tionated heparin for the treatment of venous thromboembobism:A randomized controlled trial. Ann Intern Med 123: 1-9, 1995

22. Bradbrook ID, Magnani HN, Moelker HCT, Morrison P1, Rob-

inson I, Rogers HJ, Spector RO, van Dinther T, Wijnand H:

ORG 10172: A low molecular weight heparinoid anticoagulantwith a long half-life in man. Br J Clin Pharmacol 23: 667-675,

1987

23. Nurmohamed MT. Fareed I, Hoppensteadt D, Wabenga IM, ten

Cate 1W: Pharmacological and clinical studies with bomoparan, alow molecular weight glycosaminoglycan. Semin Thromb He-

most 17 52: 205-213, 1991

24. The Diabetes Control and Complications Trial Research Group:

The effect of intensive treatment of diabetes on the developmentand progression of long-term complications in insulin-dependent

diabetes melbitus. N Engi J Med 329: 977-986, 1993

25. Viberti OC, Mogensen CE, Oroop L, Pauls IF, for the European

Microalbuminuria Captopril Study Group: Effect of captopril onprogression to clinical proteinuria in patients with insulin-depen-dent diabetes mellitus and microalbuminuria. JAMA 271: 275-

279, 1994

26. Parving H-H, Rossing P: The use of antihypertensive agents in

prevention and treatment of diabetic nephropathy. Curr OpinNephrol Hypertension 3: 292-300, 1994

27. Lewis El, Hunsicker LO, Bain RP, Rohde RD, for the Collabo-

rative Study Group: The effect of angiotensin-converting-en-

zyme inhibition on diabetic nephropathy. N Engi J Med 329:

1456-1462, 1993

28. Magnani HN: Heparin-induced thrombocytopenia (HIT): An

overview of 230 patients treated with orgaran (Org 10172).

Thromb Haemostasis 70: 554-561, 1993

29. Shaughnessy SO, Young E, Deschamps P. Hirsh I: The effects of

low molecular weight and standard heparin on calcium loss from

fetal rat calvaria. Blood 86: 1368-1373, 1995

30. Monreal M, Olive A, Lafoz E, del Rio L: Heparmns, coumarin,

and bone density [Letter]. Lancet 338: 706, 1991

31. Wardle EN: Heparmns for proliferative nephritides: Short review

on an advancing topic. Nephron 73: 515-519, 1996

32. McCaffrey TA, Falcone DF, Brayton CF. Agarwal LA: TOF-

beta activity is potentiated by heparin via dissociation of the

TOF-beta-a2-macrogbobubin inactive complex. J Cell Biol 109:441-448, 1989

33. Lindner V, Olson NE, Clowes AW, Reid MA: Inhibition of

smooth muscle cell proliferation in injured rat arteries. J Clin

Invest 90: 2044-2049, 1992

34. Imai T, Hirata Y, Emori T, Marumo F: Heparin has an inhibitory

effect on endothelin 1 synthesis and release by endothelial cells.

Hypertension 21: 353-358, 1993

35. Tiozzo R, Cingi MR, Reggiani D, Andreoli T, Calandra 5, Milani

MR, Piani 5, Marchi E, Barbanti M: Effect of desulfatation of

heparin on its anticoagulant and anti-proliferative effect. Thromb

Res 70: 99-106, 1993

36. Ichikawa I, Yoshida Y, Fogo A, Purkerson ML, Klahr 5: Effect

of heparin on the gbomerular structure and function of remnant

nephrons. Kidney mt 34: 638-644, 1988