0021-972X/90/7004-0957$02.00/0 Journal of Clinical Endocrinology and Metabolism Copyright© 1990 by The Endocrine Society
Vol. 70, No. 4 Printed in U.S.A.
Changes in the Pharmacokinetics of Plasma Total and Free Prednisolone during Daily and Intermittent Regimens* KEIGO YASUDA, EIICHI GOSHIMA, KAYOKO ADACHI, YOSHIYUKI FUWA, NORIYOSHI YAMAKITA, AND KIYOSHI MIURA Third Department of Internal Medicine, Gifu University School of Medicine, Gifu, Japan
periods compared with the pretreatment values. The decreased MCR during the on-day period was restored to the pretreatment level during the off-day period. A similar trend was observed in the changes in half-life, prolongation in the daily and on-day periods compared with the pretreatment value, and restoration to the pretreatment level during the off-day period. These alterations were not associated with the total duration or the total dosage of prednisolone administered. The results indicate that the pharmacokinetic parameters of prednisolone may periodically change during the intermittent regimen, and that off-day and on-day parameters are similar to those before therapy and during the daily period, respectively. (J Clin Endocrinol Metab 70: 957-964, 1990)
ABSTRACT. To determine the pharmacokinetic changes of prednisolone associated with differing therapy regimens, we studied 15 patients with various diseases who were treated with daily doses of prednisolone and were then placed on an intermittent regimen, [administration for 4 consecutive days (on-day period), followed by 3 days cessation (off-day period)]. The mean duration of the study and the mean total dosage were 1.6 months and 2.4 g in the daily period, respectively, and 4.7 months and 3.5 g in the intermittent period, respectively. Blood was drawn for 6 h after iv administration of 20 mg prednisolone (average, 0.36 mg/kg). Plasma total and free prednisolone concentrations were measured by RIA. On-day and off-day tests were performed during the same week. The mean MCR of both total and free prednisolone decreased significantly in the daily and on-day
P
REDNISOLONE is one of the most commonly prescribed drugs in the treatment of a wide variety of diseases and is often administered for long periods of time. Several modes of long term steroid therapy, including intermittent and alternate day regimens, have been tried in an effort to avoid undesired effects of long term treatment while maintaining its therapeutic effectiveness. However, pharmacokinetic analysis of these regimens has not yet been performed. In general, pharmacokinetic data provide a theoretical basis for quantitative analysis of drug therapy regimens. Although controversial, earlier investigations demonstrated the association of prednisolone-induced Cushingoid appearance with pharmacokinetic changes (1-4). On the other hand, no attempts have been made to determine the best therapeutic regimen of prednisolone based on a pharmacokinetic study. Various factors, such
as age, body size, and hepatic or renal function, affect the pharmacokinetics of the drug, thereby resulting in relatively wide patient to patient variability (2, 3, 5-7). To prevent the influence of the aforementioned variables on the pharmacokinetic analysis of a prednisolone therapeutic regimen, a longitudinal, but not cross-sectional, study should prove superior. However, such a long term investigation has been limited. The present study was undertaken to evaluate and compare the longitudinal changes in pharmacokinetics of plasma total and free prednisolone in each patient treated first on a daily basis and then on an intermittent regimen consisting of 4 consecutive days on therapy (onday period) and 3 days off therapy (off-day period) every week. Subjects and Methods The present study included 15 patients (15 in the total prednisolone study and 11 in the free prednisolone study), 4 men and 11 women, aged 14-59 yr (mean ± SD, 39.1 ± 13.6). Patient weight ranged from 43-67 kg (56 ± 7.2 kg). Six patients presented with systemic lupus erythematosus, 2 with nephrotic syndrome, 2 with sarcoidosis, and 1 each with Crohn's disease associated with Hashimoto's disease, aortitis syndrome, hemolytic anemia, multiple myeloma, and idiopathic thrombocy-
Received March 10, 1989. Address requests for reprints to: Dr. Keigo Yasuda, M.D., Third Department of Internal Medicine, 40 Tsukasa-machi, Gifu MZ 500, Japan. * This work was supported in part by grants from the Ministry of Health and Welfare. Disorders of the Hypothalamo-Pituitary gland, 1986-1987, and Disorders of the Adrenal Gland, 1986-1987, Japan. Presented in part at the 70th Annual Meeting of The Endocrine Society, New Orleans, LA, June 1988.
957
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 19 June 2015. at 09:41 For personal use only. No other uses without permission. . All rights reserved.
958
YASUDA ET AL.
topenic purpura (Table 1). The investigation was performed in accordance with the Helsinki Declaration, and informed consent was obtained from each subject. Prednisolone (mean total dose, 2.4 ± 1.7 g; range, 0.4-6.9 g) was initially administered daily to control the disease as quickly as possible for a period of 0.7-3.5 months (mean, 1.6 ± 0.9 months, Table 1). After attaining clinical remission, the weekly maintenance dose was divided and administered on 4 consecutive days on therapy (on-day period), followed by 3 days off therapy (off-day period) during each week (intermittent period). The intermittent regimen was started without daily administration in two patients. The duration of the intermittent period ranged from 1.2-15 months (mean, 4.4 ± 3.7 months); the mean total dose of prednisolone administered was 3.5 ± 2.7 g (range, 1.1-8.6 g; Table 1). Two thirds of the daily dose were administered in the morning, and the remaining one third at noon. Laboratory data, including renal and hepatic function tests with the duration and total dose of prednisolone administered for all patients, are shown in Table 1. There were few differences in the laboratory data among the test periods, except for the serum albumin level in the patients with nephrotic syndrome. The maximal difference in the body weights of each patient during the investigation was 2 kg. At the time of the test each patient was graded (Cushing score) for clinical glucocorticoid toxicity by the degree of Cushingoid facial features (roundness, rubor, and acne): 0, not noticeable; 1, mild; 2, moderate; and 3, marked, as shown by Bergrem et al. (3) (Table 1). For the pharmacokinetic study, prednisolone sodium hemisuccinate salt equivalent to 20 mg prednisolone (Shionogi Co. Ltd., Osaka, Japan) was iv administered to each patient for 10 s between 0800-0900 h. The body weights of the patients at the time of the test ranged from 43-67 kg (55 ± 6.8 kg), yielding a mean iv dose of 0.36 ± 0.05 mg/kg (range, 0.30-0.47 mg/kg). Blood was drawn through an antecubital vein before the iv injection and at 5, 10, 15, 30, 45, 60, 90, 120, 240, and 360 min afterward. Plasma was stored at -20 C until assayed. The pharmacokinetic study was performed in each treatment period (before therapy, daily period, on-day, and off-day in the intermittent period) for a total of two to four times. During the daily period, an iv prednisolone test was performed in the morning before ingestion of the drug. During the intermittent period, the test was performed on the last day of the on-day period (on-day test) and on the first day of the on-day period (off-day test) before the intake of prednisolone; both tests were carried out during the same week. The periods when the tests were performed in each patient are shown in Table 1. Plasma free prednisolone was measured by a modified method originally described by Hammond et al. (8) and later modified by Longcope et al. (9) in which [14C]glucose was used to monitor the movement of unbound components in plasma (8). About 1.2 x 104 dpm [14C]glucose (New England Nuclear Corp., Boston, MA) in 6 nL distilled water were incubated with plasma for 30 min at 37 C. A 0.5-mL aliquot was transferred to a MPS-3 unit containing a YMT membrane (Amicon Corp., Danvers, MA) and centrifuged at 1100 x g at 37 C for 30 min by a centrifuge with a special delicate controller for maintaining a constant temperature (Kokusan Centrifuge Co., Tokyo, Ja-
JCE & M • 1990 Vol 70 • No 4
pan). After centrifugation 30 ^L ultrafiltrate and plasma were pipetted into scintillation vials, and [14C] glucose was counted in a liquid scintillation spectrophotometer (PR-2650, Packard, Downers Grove, IL). To calculate the plasma free prednisolone level, the prednisolone concentration of the ultrafiltrate, measured by RIA, the method of which is described below, was multiplied by the ratio of [14C]glucose (disintegrations per min) in plasma to [14C]glucose (disintegrations per min) in ultrafiltrate as follows: FC = C J T C x {([14C]P/[14C]u x TC) = Cu x ([14C]p/[14C]u), where FC is the apparent free concentration of plasma prednisolone, TC is the total concentration of plasma prednisolone measured by RIA, Cu is the prednisolone concentration of ultrafiltrate measured by RIA, and [14C]P and [14C]u are the [14C]glucose counts of plasma and ultrafiltrate, respectively. Plasma free prednisolone measured by this method was compared with that measured by equilibrium dialysis (10). In equilibrium dialysis, prednisolone concentrations in plasma and dialysate were measured by RIA, and the free prednisolone concentration was calculated (11) as follows: FC = Cd x Vt -s[(TC X VP) - (Cd x Vo)] x TC, where FC is the apparent free concentration of plasma prednisolone, TC is the total concentration of plasma prednisolone measured by RIA, Cd is the prednisolone concentration in the dialysate measured by RIA, Vi is the internal volume at the end of dialysis calculated from the weight difference, Vo is the volume of dialysate, and VP is the volume of plasma sample. There was a good correlation between the two methods (r = 0.98), and the observed slope was 1.03, as shown in Fig. 1. Plasma total prednisolone and the concentration of free prednisolone in ultrafiltrate were measured in triplicate by RIA using the method of Miyachi et al. (12). Antiprednisolone rabbit serum was raised against prednisolone conjugated with BSA (13). The percent cross-reactivities of this antiserum with the various steroids, calculated using the method of Meikle et al. (14), were as follows: cortisol, 16%; cortisone, 0.2%; prednisone, 2.6%; deoxycorticosterone, 1.0%; corticosterone, 1.7%; progesterone, 0.5%; and testosterone, 0.1%. Antiprednisolone serum was used with a dilution ratio of 1:20,000. Each 50 /iL plasma, ultrafiltrate, or standard sample added to cortisol free serum (0-2.78 /imol/L) were extracted with dichloromethane. The extracted aliquot of 100 nh for plasma or 100-500 /iL for ultrafiltrate was dried and incubated with 500 (iL antiprednisolone serum and 500 nL [2,4,6,7-3H]prednisolone (~2 x 104 dpm; Amersham Corp., Arlington Heights, IL; 61 Ci/mmol) constituted in phosphate-buffered saline (pH 7.4; 0.1% BSA) at 4 C for 16 h. Bound and free [3H]prednisolone were separated with dextran-coated charcoal. Inter- and intraassay coefficients of variation were 10.7% and 7.6%, respectively. The sensitivity of this assay system was 83.2 fmol (30 pg)/tube, and the least detectable concentration of prednisolone was 13.9 nmol/L. All samples from each patient obtained in every test period were measured in the same assay to minimize variability among the tests. Pharmacokinetic parameters, such as MCR, apparent volume of distribution (Vd), and half-life in the /3-phase (distribution phase) of disappearance (T1/4j8), were determined using two compartmental models. Distribution volumes of inner
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 19 June 2015. at 09:41 For personal use only. No other uses without permission. . All rights reserved.
PREDNISOLONE KINETICS AND TREATMENT
959
TABLE 1. Laboratory data and the dose and duration of prednisolone administered Subject no. 1°
2°
3°
4°
5"
6*
Sex
K.M., 59 yr, F Crohn's + Hashimoto's diseases
K.I., 49 yr, SLE
M.O., 42 yr, nephrotic syndrome
I.O., 42 yr, sarcoidosis
Y.N., 46 yr, SLE
M.K., 52 yr,
F
M
M
F
F
BW (kg)
TP(alb) (g/dL)
Ccr
Cr
(mg/dL)
GPT (IU)
GOT
(mL/min)
(IU)
Chol-E (APH)
B
46
6.4 (3.2)
63
0.8
11
14
0.77
D On/off
47 46
6.5 (3.8) 6.7 (4.0)
1.0 1.0
22 13
16 20
0.88 1.26
B
52
7.7 (3.3)
66
0.9
14
28
0.45
D On/off
52 52
7.0 (3.8) 7.1 (3.8)
67 62
1.0 1.0
19 15
34 19
0.88 1.02
B
67
5.1 (2.8)
69
1.0
28
22
1.54
D
On/off
65 67
5.8 (3.6) 6.1 (4.0)
73 65
1.0 1.1
37 35
18 16
0.89 1.04
B
58
7.5 (3.9)
67
1.2
25
24
0.85
D On/off
58 58
7.4 (4.4)
1.2
17
25
0.77
B
54
7.6 (4.5)
1.0
13
18
1.06
D On/off
53 54
6.6 (3.8) 6.9 (4.5)
0.9 1.2
18 18
10 13
0.58 0.80
B
54
4.3 (2.8)
84
0.6
18
26
0.75
D
55 54
5.3 (3.3) 5.9 (3.6)
71
0.6
29
22
On/off
122
0.9
30
13
0.56 0.76
B
54
7.2 (4.2)
73
0.8
8
18
On/off
54
6.5 (4.0)
66
1.2
8
D
43
5.9 (3.6)
56
0.8
On/off
43
5.5 (3.6)
46
Test period
57
Duration (months)
Dose (g)
Cushing score
0.7 2.5
0.4 1.1
2 2
1.5 2.5
2.3 3.3
0 0
1.0 5.0
1.9 5.8
3 2
0.8 3.5
0.7 2.2
2 2
1.0 9.1
2.0 8.6
3 2
3.5 2.0
6.9 1.3
3 2
11
2.3
1.9
2
25
13
2.7
3.6
3
0.9'
19
14
0.70
1.2
1.2
3
SLE
7°
8°
Y.H., 21 yr, SLE
N.T., 23 yr, SLE
F
F
9°
M.N., 47 yr, hemolytic anemia
F
On/off
46
5.5 (3.9)
106
0.9
20
17
0.58
4.0
2.0
3
10°
Y.S., 14 yr, nephrotic syndrome
F
D
66
5.3 (3.3)
94
0.6
24
12
0.69
2.0
2.3
3
On/off
66
5.6 (3.6)
79
0.6
10
10
0.75
6.0
7.9
2
D
48
5.8 (3.7)
1.0
22
13
0.82
2.5
2.6
3
On/off
47
5.9 (3.6)
1.0
15
14
0.67
2.3
2.0
2
On/off
62
6.9 (3.9)
1.3
25
19
0.82
15.0
6.8
0
11*
12*
T.T., 19 yr, aortitis syndrome
K.O., 45 yr, multiple myeloma
F
M
60
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 19 June 2015. at 09:41 For personal use only. No other uses without permission. . All rights reserved.
YASUDA ET AL.
960
JCE & M • 1990 Vol 70 • No 4
TABLE 1—Continued
Subject no. 13 6
N.K., 31 yr, ITP T.I., 40 yr, SLE
14°
F.M., 56 yr, sarcoidosis
15°
Sex
Test period
M
F
F
BW (kg)
TP(alb) (g/dL)
B
57
7.2 (4.2)
On/off
57
7.2 (4.2)
B
52
7.8 (3.8)
D
52
7.2 (3.8)
B
62
6.6 (4.3)
Ccr
Cr
(mL/min)
(mg/dL)
GPT (IU)
1.1
25
22
0.82
1.1
35
15
0.72
0.8
11
19
0.9
14
20
1.2
21
19
80
90
53
GOT Chol-E Duration (IU) (APH) (months)
Dose (g)
1.5
1.9
0.7
1.3
Cushing score
24 13 2.7 1.2 0.9 62 5.1 (3.4) D M and F, Male and female; SLE, systemic lupus erythematosus; ITP, idiopathic thrombocytopenic purpura; B, D, On, and Off, before treatment, daily period, and on-day and off-day during intermittent period, respectively; TP, serum total protein; (alb), serum albumin; Ccr, creatinine clearance; Cr, serum creatinine; Chol-E, choline esterase; duration and dose, those of prednisolone administration in each period. " Both total and free prednisolone were studied. 0 Only total prednisolone was studied. (nmol/L)
500 ^* c o
0=1.O3JC+28
I 400
r =0.98 P
Vol. 70, No. 4 Printed in U.S.A.
Changes in the Pharmacokinetics of Plasma Total and Free Prednisolone during Daily and Intermittent Regimens* KEIGO YASUDA, EIICHI GOSHIMA, KAYOKO ADACHI, YOSHIYUKI FUWA, NORIYOSHI YAMAKITA, AND KIYOSHI MIURA Third Department of Internal Medicine, Gifu University School of Medicine, Gifu, Japan
periods compared with the pretreatment values. The decreased MCR during the on-day period was restored to the pretreatment level during the off-day period. A similar trend was observed in the changes in half-life, prolongation in the daily and on-day periods compared with the pretreatment value, and restoration to the pretreatment level during the off-day period. These alterations were not associated with the total duration or the total dosage of prednisolone administered. The results indicate that the pharmacokinetic parameters of prednisolone may periodically change during the intermittent regimen, and that off-day and on-day parameters are similar to those before therapy and during the daily period, respectively. (J Clin Endocrinol Metab 70: 957-964, 1990)
ABSTRACT. To determine the pharmacokinetic changes of prednisolone associated with differing therapy regimens, we studied 15 patients with various diseases who were treated with daily doses of prednisolone and were then placed on an intermittent regimen, [administration for 4 consecutive days (on-day period), followed by 3 days cessation (off-day period)]. The mean duration of the study and the mean total dosage were 1.6 months and 2.4 g in the daily period, respectively, and 4.7 months and 3.5 g in the intermittent period, respectively. Blood was drawn for 6 h after iv administration of 20 mg prednisolone (average, 0.36 mg/kg). Plasma total and free prednisolone concentrations were measured by RIA. On-day and off-day tests were performed during the same week. The mean MCR of both total and free prednisolone decreased significantly in the daily and on-day
P
REDNISOLONE is one of the most commonly prescribed drugs in the treatment of a wide variety of diseases and is often administered for long periods of time. Several modes of long term steroid therapy, including intermittent and alternate day regimens, have been tried in an effort to avoid undesired effects of long term treatment while maintaining its therapeutic effectiveness. However, pharmacokinetic analysis of these regimens has not yet been performed. In general, pharmacokinetic data provide a theoretical basis for quantitative analysis of drug therapy regimens. Although controversial, earlier investigations demonstrated the association of prednisolone-induced Cushingoid appearance with pharmacokinetic changes (1-4). On the other hand, no attempts have been made to determine the best therapeutic regimen of prednisolone based on a pharmacokinetic study. Various factors, such
as age, body size, and hepatic or renal function, affect the pharmacokinetics of the drug, thereby resulting in relatively wide patient to patient variability (2, 3, 5-7). To prevent the influence of the aforementioned variables on the pharmacokinetic analysis of a prednisolone therapeutic regimen, a longitudinal, but not cross-sectional, study should prove superior. However, such a long term investigation has been limited. The present study was undertaken to evaluate and compare the longitudinal changes in pharmacokinetics of plasma total and free prednisolone in each patient treated first on a daily basis and then on an intermittent regimen consisting of 4 consecutive days on therapy (onday period) and 3 days off therapy (off-day period) every week. Subjects and Methods The present study included 15 patients (15 in the total prednisolone study and 11 in the free prednisolone study), 4 men and 11 women, aged 14-59 yr (mean ± SD, 39.1 ± 13.6). Patient weight ranged from 43-67 kg (56 ± 7.2 kg). Six patients presented with systemic lupus erythematosus, 2 with nephrotic syndrome, 2 with sarcoidosis, and 1 each with Crohn's disease associated with Hashimoto's disease, aortitis syndrome, hemolytic anemia, multiple myeloma, and idiopathic thrombocy-
Received March 10, 1989. Address requests for reprints to: Dr. Keigo Yasuda, M.D., Third Department of Internal Medicine, 40 Tsukasa-machi, Gifu MZ 500, Japan. * This work was supported in part by grants from the Ministry of Health and Welfare. Disorders of the Hypothalamo-Pituitary gland, 1986-1987, and Disorders of the Adrenal Gland, 1986-1987, Japan. Presented in part at the 70th Annual Meeting of The Endocrine Society, New Orleans, LA, June 1988.
957
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 19 June 2015. at 09:41 For personal use only. No other uses without permission. . All rights reserved.
958
YASUDA ET AL.
topenic purpura (Table 1). The investigation was performed in accordance with the Helsinki Declaration, and informed consent was obtained from each subject. Prednisolone (mean total dose, 2.4 ± 1.7 g; range, 0.4-6.9 g) was initially administered daily to control the disease as quickly as possible for a period of 0.7-3.5 months (mean, 1.6 ± 0.9 months, Table 1). After attaining clinical remission, the weekly maintenance dose was divided and administered on 4 consecutive days on therapy (on-day period), followed by 3 days off therapy (off-day period) during each week (intermittent period). The intermittent regimen was started without daily administration in two patients. The duration of the intermittent period ranged from 1.2-15 months (mean, 4.4 ± 3.7 months); the mean total dose of prednisolone administered was 3.5 ± 2.7 g (range, 1.1-8.6 g; Table 1). Two thirds of the daily dose were administered in the morning, and the remaining one third at noon. Laboratory data, including renal and hepatic function tests with the duration and total dose of prednisolone administered for all patients, are shown in Table 1. There were few differences in the laboratory data among the test periods, except for the serum albumin level in the patients with nephrotic syndrome. The maximal difference in the body weights of each patient during the investigation was 2 kg. At the time of the test each patient was graded (Cushing score) for clinical glucocorticoid toxicity by the degree of Cushingoid facial features (roundness, rubor, and acne): 0, not noticeable; 1, mild; 2, moderate; and 3, marked, as shown by Bergrem et al. (3) (Table 1). For the pharmacokinetic study, prednisolone sodium hemisuccinate salt equivalent to 20 mg prednisolone (Shionogi Co. Ltd., Osaka, Japan) was iv administered to each patient for 10 s between 0800-0900 h. The body weights of the patients at the time of the test ranged from 43-67 kg (55 ± 6.8 kg), yielding a mean iv dose of 0.36 ± 0.05 mg/kg (range, 0.30-0.47 mg/kg). Blood was drawn through an antecubital vein before the iv injection and at 5, 10, 15, 30, 45, 60, 90, 120, 240, and 360 min afterward. Plasma was stored at -20 C until assayed. The pharmacokinetic study was performed in each treatment period (before therapy, daily period, on-day, and off-day in the intermittent period) for a total of two to four times. During the daily period, an iv prednisolone test was performed in the morning before ingestion of the drug. During the intermittent period, the test was performed on the last day of the on-day period (on-day test) and on the first day of the on-day period (off-day test) before the intake of prednisolone; both tests were carried out during the same week. The periods when the tests were performed in each patient are shown in Table 1. Plasma free prednisolone was measured by a modified method originally described by Hammond et al. (8) and later modified by Longcope et al. (9) in which [14C]glucose was used to monitor the movement of unbound components in plasma (8). About 1.2 x 104 dpm [14C]glucose (New England Nuclear Corp., Boston, MA) in 6 nL distilled water were incubated with plasma for 30 min at 37 C. A 0.5-mL aliquot was transferred to a MPS-3 unit containing a YMT membrane (Amicon Corp., Danvers, MA) and centrifuged at 1100 x g at 37 C for 30 min by a centrifuge with a special delicate controller for maintaining a constant temperature (Kokusan Centrifuge Co., Tokyo, Ja-
JCE & M • 1990 Vol 70 • No 4
pan). After centrifugation 30 ^L ultrafiltrate and plasma were pipetted into scintillation vials, and [14C] glucose was counted in a liquid scintillation spectrophotometer (PR-2650, Packard, Downers Grove, IL). To calculate the plasma free prednisolone level, the prednisolone concentration of the ultrafiltrate, measured by RIA, the method of which is described below, was multiplied by the ratio of [14C]glucose (disintegrations per min) in plasma to [14C]glucose (disintegrations per min) in ultrafiltrate as follows: FC = C J T C x {([14C]P/[14C]u x TC) = Cu x ([14C]p/[14C]u), where FC is the apparent free concentration of plasma prednisolone, TC is the total concentration of plasma prednisolone measured by RIA, Cu is the prednisolone concentration of ultrafiltrate measured by RIA, and [14C]P and [14C]u are the [14C]glucose counts of plasma and ultrafiltrate, respectively. Plasma free prednisolone measured by this method was compared with that measured by equilibrium dialysis (10). In equilibrium dialysis, prednisolone concentrations in plasma and dialysate were measured by RIA, and the free prednisolone concentration was calculated (11) as follows: FC = Cd x Vt -s[(TC X VP) - (Cd x Vo)] x TC, where FC is the apparent free concentration of plasma prednisolone, TC is the total concentration of plasma prednisolone measured by RIA, Cd is the prednisolone concentration in the dialysate measured by RIA, Vi is the internal volume at the end of dialysis calculated from the weight difference, Vo is the volume of dialysate, and VP is the volume of plasma sample. There was a good correlation between the two methods (r = 0.98), and the observed slope was 1.03, as shown in Fig. 1. Plasma total prednisolone and the concentration of free prednisolone in ultrafiltrate were measured in triplicate by RIA using the method of Miyachi et al. (12). Antiprednisolone rabbit serum was raised against prednisolone conjugated with BSA (13). The percent cross-reactivities of this antiserum with the various steroids, calculated using the method of Meikle et al. (14), were as follows: cortisol, 16%; cortisone, 0.2%; prednisone, 2.6%; deoxycorticosterone, 1.0%; corticosterone, 1.7%; progesterone, 0.5%; and testosterone, 0.1%. Antiprednisolone serum was used with a dilution ratio of 1:20,000. Each 50 /iL plasma, ultrafiltrate, or standard sample added to cortisol free serum (0-2.78 /imol/L) were extracted with dichloromethane. The extracted aliquot of 100 nh for plasma or 100-500 /iL for ultrafiltrate was dried and incubated with 500 (iL antiprednisolone serum and 500 nL [2,4,6,7-3H]prednisolone (~2 x 104 dpm; Amersham Corp., Arlington Heights, IL; 61 Ci/mmol) constituted in phosphate-buffered saline (pH 7.4; 0.1% BSA) at 4 C for 16 h. Bound and free [3H]prednisolone were separated with dextran-coated charcoal. Inter- and intraassay coefficients of variation were 10.7% and 7.6%, respectively. The sensitivity of this assay system was 83.2 fmol (30 pg)/tube, and the least detectable concentration of prednisolone was 13.9 nmol/L. All samples from each patient obtained in every test period were measured in the same assay to minimize variability among the tests. Pharmacokinetic parameters, such as MCR, apparent volume of distribution (Vd), and half-life in the /3-phase (distribution phase) of disappearance (T1/4j8), were determined using two compartmental models. Distribution volumes of inner
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 19 June 2015. at 09:41 For personal use only. No other uses without permission. . All rights reserved.
PREDNISOLONE KINETICS AND TREATMENT
959
TABLE 1. Laboratory data and the dose and duration of prednisolone administered Subject no. 1°
2°
3°
4°
5"
6*
Sex
K.M., 59 yr, F Crohn's + Hashimoto's diseases
K.I., 49 yr, SLE
M.O., 42 yr, nephrotic syndrome
I.O., 42 yr, sarcoidosis
Y.N., 46 yr, SLE
M.K., 52 yr,
F
M
M
F
F
BW (kg)
TP(alb) (g/dL)
Ccr
Cr
(mg/dL)
GPT (IU)
GOT
(mL/min)
(IU)
Chol-E (APH)
B
46
6.4 (3.2)
63
0.8
11
14
0.77
D On/off
47 46
6.5 (3.8) 6.7 (4.0)
1.0 1.0
22 13
16 20
0.88 1.26
B
52
7.7 (3.3)
66
0.9
14
28
0.45
D On/off
52 52
7.0 (3.8) 7.1 (3.8)
67 62
1.0 1.0
19 15
34 19
0.88 1.02
B
67
5.1 (2.8)
69
1.0
28
22
1.54
D
On/off
65 67
5.8 (3.6) 6.1 (4.0)
73 65
1.0 1.1
37 35
18 16
0.89 1.04
B
58
7.5 (3.9)
67
1.2
25
24
0.85
D On/off
58 58
7.4 (4.4)
1.2
17
25
0.77
B
54
7.6 (4.5)
1.0
13
18
1.06
D On/off
53 54
6.6 (3.8) 6.9 (4.5)
0.9 1.2
18 18
10 13
0.58 0.80
B
54
4.3 (2.8)
84
0.6
18
26
0.75
D
55 54
5.3 (3.3) 5.9 (3.6)
71
0.6
29
22
On/off
122
0.9
30
13
0.56 0.76
B
54
7.2 (4.2)
73
0.8
8
18
On/off
54
6.5 (4.0)
66
1.2
8
D
43
5.9 (3.6)
56
0.8
On/off
43
5.5 (3.6)
46
Test period
57
Duration (months)
Dose (g)
Cushing score
0.7 2.5
0.4 1.1
2 2
1.5 2.5
2.3 3.3
0 0
1.0 5.0
1.9 5.8
3 2
0.8 3.5
0.7 2.2
2 2
1.0 9.1
2.0 8.6
3 2
3.5 2.0
6.9 1.3
3 2
11
2.3
1.9
2
25
13
2.7
3.6
3
0.9'
19
14
0.70
1.2
1.2
3
SLE
7°
8°
Y.H., 21 yr, SLE
N.T., 23 yr, SLE
F
F
9°
M.N., 47 yr, hemolytic anemia
F
On/off
46
5.5 (3.9)
106
0.9
20
17
0.58
4.0
2.0
3
10°
Y.S., 14 yr, nephrotic syndrome
F
D
66
5.3 (3.3)
94
0.6
24
12
0.69
2.0
2.3
3
On/off
66
5.6 (3.6)
79
0.6
10
10
0.75
6.0
7.9
2
D
48
5.8 (3.7)
1.0
22
13
0.82
2.5
2.6
3
On/off
47
5.9 (3.6)
1.0
15
14
0.67
2.3
2.0
2
On/off
62
6.9 (3.9)
1.3
25
19
0.82
15.0
6.8
0
11*
12*
T.T., 19 yr, aortitis syndrome
K.O., 45 yr, multiple myeloma
F
M
60
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 19 June 2015. at 09:41 For personal use only. No other uses without permission. . All rights reserved.
YASUDA ET AL.
960
JCE & M • 1990 Vol 70 • No 4
TABLE 1—Continued
Subject no. 13 6
N.K., 31 yr, ITP T.I., 40 yr, SLE
14°
F.M., 56 yr, sarcoidosis
15°
Sex
Test period
M
F
F
BW (kg)
TP(alb) (g/dL)
B
57
7.2 (4.2)
On/off
57
7.2 (4.2)
B
52
7.8 (3.8)
D
52
7.2 (3.8)
B
62
6.6 (4.3)
Ccr
Cr
(mL/min)
(mg/dL)
GPT (IU)
1.1
25
22
0.82
1.1
35
15
0.72
0.8
11
19
0.9
14
20
1.2
21
19
80
90
53
GOT Chol-E Duration (IU) (APH) (months)
Dose (g)
1.5
1.9
0.7
1.3
Cushing score
24 13 2.7 1.2 0.9 62 5.1 (3.4) D M and F, Male and female; SLE, systemic lupus erythematosus; ITP, idiopathic thrombocytopenic purpura; B, D, On, and Off, before treatment, daily period, and on-day and off-day during intermittent period, respectively; TP, serum total protein; (alb), serum albumin; Ccr, creatinine clearance; Cr, serum creatinine; Chol-E, choline esterase; duration and dose, those of prednisolone administration in each period. " Both total and free prednisolone were studied. 0 Only total prednisolone was studied. (nmol/L)
500 ^* c o
0=1.O3JC+28
I 400
r =0.98 P
