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de Nijs RNJ, Jacobs JWG, Lems WF, Laan RFJ, Algra A, Huisman AM, Buskens E, de Laet CED, Oostveen ACM, Geusens PPMM, Bruyn GAW, Dijkmans BAC, Bijlsma JWJ. Alendronate or alfacalcidol in glucocorticoid-induced osteoporosis. N Engl J Med 2006; 355:675-84. [PMID: 16914703 DOI: 10.1056/nejmoa053569] [Citation(s) in RCA: 166] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Treatment with glucocorticoids is associated with bone loss starting soon after therapy is initiated and an increased risk of fracture. METHODS We performed a randomized, double-placebo, double-blind clinical trial of 18 months' duration among patients with a rheumatic disease who were starting glucocorticoids at a daily dose that was equivalent to at least 7.5 mg of prednisone. A total of 201 patients were assigned to receive either alendronate (10 mg) and a placebo capsule of alfacalcidol daily or alfacalcidol (1 microg) and a placebo tablet of alendronate daily. The primary outcome was the change in bone mineral density of the lumbar spine in 18 months; the secondary outcome was the incidence of morphometric vertebral deformities. RESULTS A total of 100 patients received alendronate, and 101 received alfacalcidol; 163 patients completed the study. The bone mineral density of the lumbar spine increased by 2.1 percent in the alendronate group (95 percent confidence interval, 1.1 to 3.1 percent) and decreased by 1.9 percent in the alfacalcidol group (95 percent confidence interval, -3.1 to -0.7 percent). At 18 months, the mean difference of change in bone mineral density between the two groups was 4.0 percent (95 percent confidence interval, 2.4 to 5.5 percent). Three patients in the alendronate group had a new vertebral deformity, as compared with eight patients in the alfacalcidol group (of whom three had symptomatic vertebral fractures) (hazard ratio, 0.4; 95 percent confidence interval, 0.1 to 1.4). CONCLUSIONS During this 18-month trial in patients with rheumatic diseases, alendronate was more effective in the prevention of glucocorticoid-induced bone loss than was alfacalcidol. (ClinicalTrials.gov number, NCT00138983 [ClinicalTrials.gov].).
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Affiliation(s)
- Ron N J de Nijs
- Department of Rheumatology and Clinical Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.
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de Nijs RNJ, Jacobs JWG, Algra A, Lems WF, Bijlsma JWJ. Prevention and treatment of glucocorticoid-induced osteoporosis with active vitamin D3 analogues: a review with meta-analysis of randomized controlled trials including organ transplantation studies. Osteoporos Int 2004; 15:589-602. [PMID: 15138667 DOI: 10.1007/s00198-004-1614-5] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2003] [Accepted: 02/09/2004] [Indexed: 10/26/2022]
Abstract
The aim of this review with meta-analysis was to determine if there is a rationale to use activated forms of vitamin D3 to treat or prevent glucocorticoid-induced osteoporosis, and to compare the effect of active vitamin D3 metabolites with that of other anti-osteoporosis therapies. We performed a systemic search using MEDLINE/PubMed (1966-2003). Animal studies and clinical trials involving humans with data on therapy to treat or prevent glucocorticoid-induced osteoporosis with active vitamin D3 analogues were included. Animal studies and basic research studies with active vitamin D3 were reviewed (qualitative review). Meta-analysis (quantitative review) on clinical trials (including organ transplantation studies) was performed with percent change in lumbar spine bone mineral density or bone mineral content as the primary outcome measure; the secondary outcome measure was incidence of vertebral fractures. Fifty-four articles were found. Animal and basic research studies showed that active vitamin D3 analogues can inhibit bone loss during treatment with glucocorticoids. Concerning the effect on bone mineral density, the pooled effect size of active vitamin D3 analogues compared with no treatment, placebo, plain vitamin D3 and/or calcium was 0.35 (95% confidence interval (CI) 0.18, 0.52). Compared with bisphosphonates, the pooled effect size was -1.03 (95% CI -1.71, -0.36). The pooled estimate of the relative risk for vertebral fractures of active vitamin D3 analogues compared with no treatment, placebo, plain vitamin D3 and/or calcium was 0.56 (95% CI 0.34, 0.92) and compared with bisphosphonates it was 1.20 (95% CI 0.32, 4.55). Active vitamin D3 analogues not only preserve bone during glucocorticoid therapy more effectively than no treatment, placebo, plain vitamin D3 and/or calcium, but are also more effective in decreasing the risk of vertebral fractures. Bisphosphonates, however, are more effective in preserving bone and decreasing the risk of vertebral fractures than active vitamin D3 analogues.
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Affiliation(s)
- R N J de Nijs
- Department of Rheumatology & Clinical Immunology, F02.127, University Medical Center Utrecht, PO Box 85500, 3508 GA, The Netherlands.
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Abstract
The review provides an evaluation of the therapeutic potential of vitamin D analogues in the context of the current understanding of vitamin D biochemistry, molecular biology and physiology. Vitamin D activity results from several circulating and intracellular physiological metabolites acting simultaneously through at least three receptors. Common analogues are reviewed. Although most vitamin D analogues have traditionally been analogues of 1,25-dihydroxyvitamin D, it may be better to deliver high doses of base vitamin or (analogues) of 25-hydroxyvitamin D. This would permit physiological endocrine, paracrine and autocrine vitamin D metabolism. Agonists or antagonists of tissue-specific vitamin D metabolic pathways could be coadministered. The importance of measuring endogenous vitamin D metabolites during in vivo studies and the pitfalls of extending data across species and time are emphasised. Human vitamin D analogue trials should include direct comparison against the related endogenous metabolite.
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Affiliation(s)
- Mark S Stein
- Department of Diabetes and Endocrinology, The Royal Melbourne Hospital, Parkville, Victoria 3050, Australia
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Toyran N, Severcan F. Competitive effect of vitamin D2 and Ca2+ on phospholipid model membranes: an FTIR study. Chem Phys Lipids 2003; 123:165-76. [PMID: 12691849 DOI: 10.1016/s0009-3084(02)00194-9] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The interaction of Ca(2+), with dipalmitoyl phosphatidylcholine (DPPC) model membranes was studied in the presence and absence of vitamin D(2) by using Fourier transform infrared spectroscopy. Addition of vitamin D(2) and/or Ca(2+) into pure DPPC liposomes shifts the phase transition to higher temperature, orders and decreases the dynamics of the acyl chains in both phases and does not induce hydrogen bond formation in the interfacial region. Moreover, the dynamics of the head group of the phospholipid decreases in both phases. The addition of vitamin D(2) into DPPC liposomes containing Ca(2+), decreases the effect of Ca(2+) at all the functional groups under investigation. Similarly, the effect of vitamin D(2) also decreases in the presence of Ca(2+). This behavior is dominant at high Ca(2+) concentrations. Our results show how simultaneous presence of vitamin D(2) and Ca(2+) alter the behavior of each other, which is reflected as a decrease in the interactions between the ions and vitamin D(2) within the membrane.
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Affiliation(s)
- Neslihan Toyran
- Department of Biology, Middle East Technical University, 06531 Ankara, Turkey
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Finch JL, Dusso AS, Pavlopoulos T, Slatopolsky EA. Relative potencies of 1,25-(OH)(2)D(3) and 19-Nor-1,25-(OH)(2)D(2) on inducing differentiation and markers of bone formation in MG-63 cells. J Am Soc Nephrol 2001; 12:1468-1474. [PMID: 11423575 DOI: 10.1681/asn.v1271468] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
19-Nor-1,25-(OH)(2)D(2), an analog of 1,25-(OH)(2)D(3), is used to treat secondary hyperparathyroidism because it suppresses parathyroid hormone synthesis and secretion with lower calcemic and phosphatemic activities. 19-Nor-1,25-(OH)(2)D(2) is approximately 10 times less active than 1,25-(OH)(2)D(3) in promoting bone resorption, which accounts in part for the low potency of this analog in increasing serum calcium and phosphorus. Concern that 19-nor-1,25-(OH)(2)D(2) also could be less potent than 1,25-(OH)(2)D(3) on bone formation led to a comparison of the potency of both compounds on osteoblasts. In the human osteoblast-like cell line MG-63, 1,25-(OH)(2)D(3) and 19-nor-1,25-(OH)(2)D(2) had a similar potency in upregulating vitamin D receptor content and suppressing proliferation. Both sterols caused a similar reduction in DNA content and proliferating cell nuclear antigen protein expression. Time-course and dose-response studies on 1,25-(OH)(2)D(3) and 19-nor-1,25-(OH)(2)D(2) induction of the marker of bone formation, osteocalcin, showed overlapping curves. The effects on alkaline phosphatase (ALP) activity also were studied in MG-63 cells that had been co-treated with either sterol and transforming growth factor-beta, an enhancer of 1,25-(OH)(2)D(3)-induced ALP activity in this cell line. Transforming growth factor-beta alone had no effect, whereas 1,25-(OH)(2)D(3) and 19-nor-1,25-(OH)(2)D(2) increased ALP activity similarly. These studies demonstrate that 19-nor-1,25-(OH)(2)D(2) has the same potency as 1,25-(OH)(2)D(3) not only in inducing vitamin D receptor content, osteocalcin levels, and ALP activity but also in controlling osteoblastic growth. Therefore, it is unlikely that 19-nor-1,25-(OH)(2)D(2) would have deleterious effects on bone remodeling.
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Affiliation(s)
- Jane L Finch
- Renal Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Adriana S Dusso
- Renal Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Tricia Pavlopoulos
- Renal Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Eduardo A Slatopolsky
- Renal Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
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Frazão JM, Elangovan L, Maung HM, Chesney RW, Acchiardo SR, Bower JD, Kelley BJ, Rodriguez HJ, Norris KC, Robertson JA, Levine BS, Goodman WG, Gentile D, Mazess RB, Kyllo DM, Douglass LL, Bishop CW, Coburn JW. Intermittent doxercalciferol (1alpha-hydroxyvitamin D(2)) therapy for secondary hyperparathyroidism. Am J Kidney Dis 2000; 36:550-61. [PMID: 10977787 DOI: 10.1053/ajkd.2000.16193] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Hypercalcemia and hyperphosphatemia frequently necessitate vitamin D withdrawal in hemodialysis patients with secondary hyperparathyroidism. In short-term trials, doxercalciferol (1alpha-hydroxyvitamin D(2) [1alphaD(2)]) suppressed intact parathyroid hormone (iPTH) effectively with minimal increases in serum calcium and phosphorus (P) levels. This modified, double-blinded, controlled trial examined the efficacy and safety of 1alphaD(2) use in 138 hemodialysis patients with moderate to severe secondary hyperparathyroidism by using novel dose titration; 99 patients completed the study. Hemodialysis patients with secondary hyperparathyroidism were enrolled onto this study, consisting of washout (8 weeks), open-label 1alphaD(2) treatment (16 weeks), and randomized, double-blinded treatment with 1alphaD(2) or placebo (8 weeks). Oral 1alphaD(2) was administered at each hemodialysis session, with doses titrated to achieve target iPTH levels of 150 to 300 pg/mL. Baseline iPTH levels (897 +/- 52 [SE] pg/mL) decreased by 20% +/- 3.4% by week 1 (P: < 0.001) and by 55% +/- 2.9% at week 16; iPTH levels returned to baseline during placebo treatment but remained suppressed with 1alphaD(2) treatment. In 80% of the patients, iPTH level decreased by 70%, reaching the target level in 83% of the patients. Grouping patients by entry iPTH level (<600, 600 to 1,200, and >1,200 pg/mL) showed rapid iPTH suppression in the group with the lowest level; greater doses and longer treatment were required in the group with the highest level. During open-label treatment, serum calcium and P levels were 9.2 +/- 0.84 (SD) to 9.7 +/- 1.05 mg/dL and 5.4 +/- 1.10 to 5.9 +/- 1.55 mg/dL, respectively. During double-blinded treatment, serum calcium levels were slightly greater with 1alphaD(2) than placebo, but P levels did not differ. During double-blinded treatment, 3.26% and 0.46% of serum calcium measurements exceeded 11.2 mg/dL with 1alphaD(2) and placebo, respectively (P: < 0.01); median level was 11.6 mg/dL during hypercalcemia. Intermittent oral 1alphaD(2) therapy effectively suppresses iPTH in hemodialysis patients with secondary hyperparathyroidism, with acceptable mild hypercalcemia and hyperphosphatemia.
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Affiliation(s)
- J M Frazão
- Medical and Research Services, Veterans Affairs West Los Angeles Healthcare Center, Los Angeles, CA, USA
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Knutson JC, LeVan LW, Valliere CR, Bishop CW. Pharmacokinetics and systemic effect on calcium homeostasis of 1 alpha,24-dihydroxyvitamin D2 in rats. Comparison with 1 alpha,25-dihydroxyvitamin D2, calcitriol, and calcipotriol. Biochem Pharmacol 1997; 53:829-37. [PMID: 9113104 DOI: 10.1016/s0006-2952(97)00004-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
1 alpha,24-Dihydroxyvitamin D2 (1 alpha,24(OH)2D2) is a metabolite of 1 alpha-hydroxyvitamin D2 (1 alpha-OH-D2), a prodrug in development as a treatment for secondary hyperparathyroidism occurring in end stage renal disease. This prodrug has a broader therapeutic index than the corresponding vitamin D3 analogue, possibly because hepatic metabolism of 1 alpha-OH-D2 shifts at higher dose levels from 1 alpha,25-dihydroxyvitamin D2 (1 alpha,25(OH)2D2) to 1 alpha,24(OH)2D2. In this report, we present the pharmacokinetics of 1 alpha,24(OH)2D2 and its systemic effects on serum and urine calcium in rats. These properties were compared with those of 1 alpha,25(OH)2D2, calcitriol, the active metabolite of endogenous vitamin D3, and calcipotriol, a vitamin D analogue noted for its rapid clearance and minimal effect on calcium homeostasis. Comparison of the blood concentration curves from time zero to infinity indicated that 1 alpha,24(OH)2D2 had about one-fifth the systemic exposure of 1 alpha,25(OH)2D2 or calcitriol, but almost 30 times that of calcipotriol. The oral bioavailabilities and circulating half-lives of 1 alpha,24(OH)2D2 and calcitriol were similar, whereas those of calcipotriol were much less. In vitamin D-deficient rats, oral doses of 1 alpha,25(OH)2D2 and calcitriol produced similar dose-dependent increases in serum calcium, whereas an oral dose 30 times greater was required for 1 alpha,24(OH)2D2 to produce a similar response. Dose-response curves generated after oral and subcutaneous administration of 1 alpha,24(OH)2D2, calcitriol, and calcipotriol to normal rats indicated that 1 alpha,24(OH)2D2 increases serum and urine calcium to a much lesser extent than calcitriol, and to a slightly greater extent than calcipotriol. These properties of 1 alpha,24(OH)2D2 suggest that production of this metabolite from 1 alpha-OH-D2 contributes to the lowered toxicity of 1 alpha-OH-D2 and indicate that 1 alpha,24(OH)2D2 contributes to the lowered toxicity of 1 alpha-OH-D2 and indicate that 1 alpha,24(OH)2D2 itself has therapeutic potential.
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Affiliation(s)
- J C Knutson
- Bone Care International, Inc., Madison, WI 53713, USA
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Tan AU, Levine BS, Mazess RB, Kyllo DM, Bishop CW, Knutson JC, Kleinman KS, Coburn JW. Effective suppression of parathyroid hormone by 1 alpha-hydroxy-vitamin D2 in hemodialysis patients with moderate to severe secondary hyperparathyroidism. Kidney Int 1997; 51:317-23. [PMID: 8995749 DOI: 10.1038/ki.1997.39] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Calcitriol, as used for treating secondary hyperparathyroidism, has a low therapeutic index. The safety and efficacy of the vitamin D analog, 1 alpha (OH)-vitamin D2, (1 alpha D2), which has less toxicity in animals than 1 alpha (OH)-vitamin D3, was tested in a multicenter study of 24 hemodialysis patients with secondary hyperparathyroidism [serum intact (i) PTH > 400 pg/ml]. Calcium-based phosphate binders alone were used to maintain serum phosphorus < or = 6.9 mg/dl. After eight weeks without calcitriol (washout), oral 1 alpha D2, 4 micrograms/day or 4 micrograms thrice weekly, was started, with the dose adjusted over 12 weeks to maintain serum iPTH between 130 and 250 pg/ml. Pre-treatment serum iPTH fell from 672 +/- 70 pg/ml (SEM) to 289 +/- 36 after treatment (P < 0.05). The maximal decrease in serum iPTH was 48 to 96%, with 87.5% of patients reaching target iPTH levels. The final dose of 1 alpha D2 average 14.2 micrograms/week. Pre-treatment serum calcium rose modestly from 8.8 +/- 0.2 mg/dl to 9.5 +/0 0.2 after treatment (P < 0.001). Only once did modest hypercalcemia (serum Ca > 11.2 mg/dl) necessitate stopping treatment. Neither the average serum P level, the incidence of hyperphosphatemia, nor the dose of phosphate binders changed from washout to treatment. Thus, oral 1 alpha D2 is highly efficacious in suppressing secondary hyperparathyroidism in hemodialysis patients and is safe despite exclusive use of calcium-based phosphate-binders. Future studies should clarify the optimal dosage regimen.
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Affiliation(s)
- A U Tan
- Medical Service, West Los Angeles Veterans Affairs Medical Center (Wadsworth Division), California, USA
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Gallagher JC, Bishop CW, Knutson JC, Mazess RB, DeLuca HF. Effects of increasing doses of 1 alpha-hydroxyvitamin D2 on calcium homeostasis in postmenopausal osteopenic women. J Bone Miner Res 1994; 9:607-14. [PMID: 8053388 DOI: 10.1002/jbmr.5650090504] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This study is the first reported administration of 1 alpha-hydroxyvitamin D2 (1 alpha-OHD2) to human subjects. A total of 15 postmenopausal osteopenic women were given increasing oral doses of 1 alpha-OHD2, beginning with a low dose of 0.5 microgram/day. In 15 subjects, the doses were raised at weekly intervals to 1.0, 2.0, 4.0, and 5.0 micrograms/day, and in 5 of these subjects, the dose was further increased to 8.0 or 10.0 micrograms/day. Mean urine calcium +/- SEM showed a dose-related increase from 134 +/- 17 mg/24 h on 0.5 microgram/day to 198 +/- 21 mg/24 h on 4.0 micrograms/day (p < 0.05) and to 241 +/- 35 mg/24 h on 5.0 micrograms/day (p < 0.05). No subjects had hypercalciuria (> 350 mg/24 h, the upper limit of the laboratory normal range) at doses less than 5.0 micrograms/day; 5 subjects had hypercalciuria at or above 5.0 micrograms/day (3 at 5.0 micrograms/day, 1 at 8.0 micrograms/day, and 1 at 10.0 micrograms/day). Mean serum calcium increased slightly on the 4.0 micrograms dose only (p < 0.05) but remained well within the normal range. Mean creatinine clearance and BUN, used as measures of renal function, showed no significant changes. Routine blood and urine assays also showed no significant changes.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J C Gallagher
- Bone Metabolism Unit, Creighton University School of Medicine, Omaha, Nebraska
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