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Effects of teriparatide on quality of life in postmenopausal women with osteoporosis
ABSTRACTS / Bone 42 (2008) S17–S110
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tion through accumulation of mevalonate pathway intermediates, such as IPP/DMAPP, selectively in CD14 + ve monocytes. The accumulation of the metabolites selectively in this cell type is probably due to highly efficient drug uptake by endocytosis compared to other cell types.
be exposed to BP. In conclusion, these results show that osteoclasts are the only cell type in bone that internalise substantial quantities of BP in vivo, although FAM–RIS labelling of some osteocytic lacunae suggests that osteocytes could also be affected by BPs in vivo.
doi:10.1016/j.bone.2007.12.159
doi:10.1016/j.bone.2007.12.160
150 Use of a fluorescent analogue of risedronate to study localisation and cellular uptake of bisphosphonates in vivo Anke J. Roelofs a, Fraser P. Coxon a, Frank H. Ebetino b, Joy F. Bala c, Boris A. Kashemirov c, Charles E. McKenna c, Michael J. Rogers a a Department of Medicine and Therapeutics, University of Aberdeen, Aberdeen, United Kingdom b Procter and Gamble Pharmaceuticals, Cincinnati, USA c Department of Chemistry, University of Southern California, Los Angeles, USA
151 Effects of teriparatide on quality of life in postmenopausal women with osteoporosis Jan Rosa a, Petr Kasalicky a, Ivana Mala b a Department of Osteology, DC MEDISCAN-Euromedic, Prague, Czech Republic b Department of Informatic Science, University of Economics, Prague, Czech Republic
Bisphosphonates (BPs) are effective anti-resorptive agents due to their bone-targetting properties and efficient internalisation by bone-resorbing osteoclasts. However, it is still unclear exactly where BPs localise within the skeleton, and whether any non-osteoclast cells are directly affected by these drugs in vivo. We have used fluorescein–risedronate (FAM–RIS) to investigate cellular uptake and localisation of BP in newborn rabbits. Three-day-old rabbits were subcutaneously injected with 0.5 mg/kg FAM–RIS and sacrificed 24 h later. Using confocal microscopy, FAM-RIS uptake could be clearly detected in osteoclasts in vivo, both in histological sections of ulnae, and in osteoclasts purified ex vivo using immunomagnetic bead separation. In contrast, uptake by other bone marrow cells (BMCs) in vivo was very limited. Flow cytometry demonstrated only a slight increase in mean fluorescence of BMCs in 3 out of 4 experiments (± 0.5 fold mean increase) in FAM–RIS-treated animals as compared to vehicle-treated controls, and apart from multinucleated osteoclasts and a very small proportion of mononuclear cells, no intracellular uptake could be detected by confocal microscopy, either in cells isolated ex vivo, or in histological sections. In comparison, ex vivo treatment of BMCs isolated from the same animals with 1 μM or 5 μM FAM–RIS for 2 h resulted in an approximately 5–10 fold and a 20–25-fold increase, respectively, in mean fluorescence as compared to vehicle-treated cells, and intracellular uptake was confirmed by confocal microscopy. Histological analysis of the ulnae and vertebrae revealed clear FAM–RIS labelling of bone surfaces in vivo, especially around the growth plate. More detailed analysis further revealed strong labelling around vascular channels within the bone matrix. Interestingly, osteocytic lacunae in close proximity to these vascular channels also showed evidence of FAM–RIS binding. Moreover, FAM–RIS was also localized to the lacunae of newly embedded osteocytes. This suggests that BPs may exert direct effects on osteocytes in vivo through extracellular mechanisms, as previously suggested, although our findings indicate that only a small subset of osteocytes may
Background: Vertebral fractures are most abundant fragility fractures thereby representing most frequent clinical manifestation of osteoporosis. Vertebral fragility fractures are frequently associated with pain, functional limitation and decreased quality of life, which may deeply influence general health status, in particular in patients with severe and/or multiple vertebral fractures. Chronic back pain is associated with depression, loss of independence and inability to work. Teriparatide [TPTD, recombinant 1–34 aminoterminal fragment of human parathormone, rhPTH (1–34)] significantly decreases risk of both vertebral and nonvertebral fractures. Osteoporotic women receiving TPTD experience significantly less back pain including its most severe forms compared to placebo, alendronate and hormonal replacement therapy. The aim of our study was to evaluate influence of therapy with TPTD on quality of life in a clinical practice. Patients: 12 patients with postmenopausal osteoporosis who met local criteria for therapy with TPTD, i.e. Total Hip BMD (T-score) b − 2.9 & multiple vertebral fractures. Data from 3 months follow-up since treatment initiation are presented. Methods: BMD (GE Lunar Prodigy, German Reference Database), questionnaires: EQ-5D: descriptive system and selfreported health status (visual analogue scale, VAS); back pain (VAS); SF-36. Results: Mean patient’s age was 71.6 ± 4.7 years, mean BMD values (T/Z-score): Lumbar Spine − 4.1/− 2.5, Femoral Neck − 3.5/− 1.9, Total Hip − 3.4/− 2.2. Mean number of vertebral fractures 5.4 ± 2.8, history of nonvertebral fragility fracture: 83.3% (10 out of 12 patients), history of hip fracture: 16.7% (2 out of 12). EQ-5D: some degree of improvement was noted in 10 out of 12 patients (83.33%), back pain relief reported 11 out of 12 patients (91.67%). There were significant improvements (month 3 compared to baseline) for both selfreported health state (60.0 vs. 48.7) and back pain (45.6 vs. 70.8) /p b 0.05 for both comparisons/. SF-36: improvements were noted for all items, statistical significance was reached for following domains: physical functioning, pain, overall health status, vitality, functional limitation for emotional reasons and mental status /p b 0.05/.
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ABSTRACTS / Bone 42 (2008) S17–S110
Conclusion: We conclude that even short treatment with TPTD significantly reduces back pain (VAS), improves selfreported health status (EQ-5D-VAS) and results in improvement of quality of life in 6 out of 8 domains of the SF-36 questionnaire.
this subgroup is representative of the majority of patients usually treated for PMO. Reference [1] Chesnut CH, et al. J Bone Miner Res 2004;19:1241–9.
doi:10.1016/j.bone.2007.12.161 doi:10.1016/j.bone.2007.12.162
152 Oral ibandronate reduces non-vertebral fracture risk in postmenopausal osteoporosis: Results from a sub-analysis of a pivotal study Jacob A. Stakkestad a, Ronald Emkey b, Colin Neate c, Charles H. Chesnut d a CECOR, Haugesund, Norway b Radiant Research, Wyomissing, USA c Roche Products Limited, Welwyn Garden City, United Kingdom d Osteoporosis Research Group, University of Washington, Seattle, USA The nitrogen-containing bisphosphonate, ibandronate (Bonviva®), has proven efficacy for the treatment of postmenopausal osteoporosis (PMO). The 3-year, randomised, double-blind BONE (Bonviva Osteoporosis Trial in North America and Europe) study assessed the effect of daily (2.5 mg) or intermittent (20 mg every other day for 12 doses every 3 months) oral ibandronate versus placebo on vertebral fracture risk. The eligible participants were women (n = 2946) aged between 55– 80 years with PMO (≥ 5 years’ onset; 1–4 prevalent vertebral fractures; lumbar spine BMD T-score b − 2.0 SD). All patients received vitamin D (400IU) and oral calcium (500 mg daily). Daily ibandronate showed significant antifracture efficacy versus placebo, reducing the incidence of vertebral fractures (primary endpoint) by 62% (p = 0.0001) [1]. The study population was at relatively low risk for non-vertebral fractures, only 30.5% had a low femoral neck BMD T-score ≤ − 2.5 SD whereas N 30% had femoral neck BMD T-score N −1.6 SD at baseline. Unsurprisingly, no statistically significant effect on non-vertebral fractures was seen in the overall population, as it is not possible to detect a true reduction in fractures without appropriate fracture risk and a sufficient number of events. Therefore, a sub-analysis was carried out in 282 women at higher risk for non-vertebral fractures, who had a lumbar spine BMD T-score b −2.5 and a history of clinical fractures in the past 5 years. The results of this sub-analysis are presented here. Daily oral ibandronate reduced the risk of non-vertebral fractures to 6.2% (n = 154) versus 15.4% (n = 128) with placebo. This corresponds to a significant relative risk reduction of 62% (p = 0.025) for daily ibandronate versus placebo. These findings are consistent with a previously completed BONE study subgroup analysis in patients with similar non-vertebral fracture risk,1 which demonstrated a 69% (p = 0.012) relative risk reduction. The current analysis confirms that 2.5 mg daily oral ibandronate significantly reduces non-vertebral fracture risk versus placebo in a BONE study higher-risk subgroup. Importantly,
153 Structure activity relationships of phosphonocarboxylate inhibitors of rab geranylgeranyl transferase Charlotte A. Stewart a, Rudi Baron b, Mong S. Marma c, Katarzyna M. Blazewska c, Boris A. Kashemirov c, Frank H. Ebetino d, Charles E. McKenna c, Michael J. Rogers a, Fraser P. Coxon a a Bone Research Programme, University of Aberdeen, Aberdeen, United Kingdom b Cell and Molecular Biology, Imperial College, London, United Kingdom c Department of Chemistry, University of Southern California, Los Angeles, USA d Procter & Gamble Pharmaceuticals, Mason, USA Phosphonocarboxylates (PCs) are analogues of bisphosphonates in which one of the phosphonate groups has been replaced with a carboxylate group. We have found that these drugs have no effect on farnesyl diphosphate synthase (FPPS), but selectively inhibit a different enzyme of the mevalonate pathway, Rab geranylgeranyl transferase (RGGT), which is responsible for the prenylation of Rab GTPases. Since the first inhibitor that we identified (3-PEHPC) also inhibits bone resorption, it is likely that PCs disrupt osteoclast function by inhibiting Rab-dependent vesicular trafficking pathways in these cells. We have now compared the ability of five PCs to inhibit RGGT, disrupt Rab prenylation in cells, reduce macrophage viability and inhibit bone resorption in vitro. We found that 3-PEHPC and 3-PEPC were of similar potency (IC50 values 336 μM and 387 μM, respectively) for inhibiting RGGT in isolated enzyme assays, while 3-IPEHPC, the PC of minodronate (PG1401135) was 25–30× more potent (IC50 13 μM). The remaining 2 PCs were unable to inhibit RGGT. Similar differences were found in the ability of the PCs to inhibit Rab prenylation in J774 macrophages, while the ability of the PCs to reduce the viability of these cells also correlated with inhibition of Rab prenylation. Moreover, macrophages isolated from gunmetal mice, which have a mutation in RGGT that results in a 80% decrease in enzyme activity, were much more sensitive to 3-PEHPC and 3-IPEHPC than macrophages from heterozygous animals (in which RGGT activity is similar to wild-type animals). This strongly suggests that the cytotoxicity of the PCs is the result of inhibition of Rab prenylation. Interestingly, treatment of osteoclasts with PCs for 48 h dose-dependently caused the accumulation of large, actin-bound vacuoles, which were not seen in untreated osteoclasts. This appears to be the result of inhibition of RGGT, since only those PCs that inhibited Rab
S85
tion through accumulation of mevalonate pathway intermediates, such as IPP/DMAPP, selectively in CD14 + ve monocytes. The accumulation of the metabolites selectively in this cell type is probably due to highly efficient drug uptake by endocytosis compared to other cell types.
be exposed to BP. In conclusion, these results show that osteoclasts are the only cell type in bone that internalise substantial quantities of BP in vivo, although FAM–RIS labelling of some osteocytic lacunae suggests that osteocytes could also be affected by BPs in vivo.
doi:10.1016/j.bone.2007.12.159
doi:10.1016/j.bone.2007.12.160
150 Use of a fluorescent analogue of risedronate to study localisation and cellular uptake of bisphosphonates in vivo Anke J. Roelofs a, Fraser P. Coxon a, Frank H. Ebetino b, Joy F. Bala c, Boris A. Kashemirov c, Charles E. McKenna c, Michael J. Rogers a a Department of Medicine and Therapeutics, University of Aberdeen, Aberdeen, United Kingdom b Procter and Gamble Pharmaceuticals, Cincinnati, USA c Department of Chemistry, University of Southern California, Los Angeles, USA
151 Effects of teriparatide on quality of life in postmenopausal women with osteoporosis Jan Rosa a, Petr Kasalicky a, Ivana Mala b a Department of Osteology, DC MEDISCAN-Euromedic, Prague, Czech Republic b Department of Informatic Science, University of Economics, Prague, Czech Republic
Bisphosphonates (BPs) are effective anti-resorptive agents due to their bone-targetting properties and efficient internalisation by bone-resorbing osteoclasts. However, it is still unclear exactly where BPs localise within the skeleton, and whether any non-osteoclast cells are directly affected by these drugs in vivo. We have used fluorescein–risedronate (FAM–RIS) to investigate cellular uptake and localisation of BP in newborn rabbits. Three-day-old rabbits were subcutaneously injected with 0.5 mg/kg FAM–RIS and sacrificed 24 h later. Using confocal microscopy, FAM-RIS uptake could be clearly detected in osteoclasts in vivo, both in histological sections of ulnae, and in osteoclasts purified ex vivo using immunomagnetic bead separation. In contrast, uptake by other bone marrow cells (BMCs) in vivo was very limited. Flow cytometry demonstrated only a slight increase in mean fluorescence of BMCs in 3 out of 4 experiments (± 0.5 fold mean increase) in FAM–RIS-treated animals as compared to vehicle-treated controls, and apart from multinucleated osteoclasts and a very small proportion of mononuclear cells, no intracellular uptake could be detected by confocal microscopy, either in cells isolated ex vivo, or in histological sections. In comparison, ex vivo treatment of BMCs isolated from the same animals with 1 μM or 5 μM FAM–RIS for 2 h resulted in an approximately 5–10 fold and a 20–25-fold increase, respectively, in mean fluorescence as compared to vehicle-treated cells, and intracellular uptake was confirmed by confocal microscopy. Histological analysis of the ulnae and vertebrae revealed clear FAM–RIS labelling of bone surfaces in vivo, especially around the growth plate. More detailed analysis further revealed strong labelling around vascular channels within the bone matrix. Interestingly, osteocytic lacunae in close proximity to these vascular channels also showed evidence of FAM–RIS binding. Moreover, FAM–RIS was also localized to the lacunae of newly embedded osteocytes. This suggests that BPs may exert direct effects on osteocytes in vivo through extracellular mechanisms, as previously suggested, although our findings indicate that only a small subset of osteocytes may
Background: Vertebral fractures are most abundant fragility fractures thereby representing most frequent clinical manifestation of osteoporosis. Vertebral fragility fractures are frequently associated with pain, functional limitation and decreased quality of life, which may deeply influence general health status, in particular in patients with severe and/or multiple vertebral fractures. Chronic back pain is associated with depression, loss of independence and inability to work. Teriparatide [TPTD, recombinant 1–34 aminoterminal fragment of human parathormone, rhPTH (1–34)] significantly decreases risk of both vertebral and nonvertebral fractures. Osteoporotic women receiving TPTD experience significantly less back pain including its most severe forms compared to placebo, alendronate and hormonal replacement therapy. The aim of our study was to evaluate influence of therapy with TPTD on quality of life in a clinical practice. Patients: 12 patients with postmenopausal osteoporosis who met local criteria for therapy with TPTD, i.e. Total Hip BMD (T-score) b − 2.9 & multiple vertebral fractures. Data from 3 months follow-up since treatment initiation are presented. Methods: BMD (GE Lunar Prodigy, German Reference Database), questionnaires: EQ-5D: descriptive system and selfreported health status (visual analogue scale, VAS); back pain (VAS); SF-36. Results: Mean patient’s age was 71.6 ± 4.7 years, mean BMD values (T/Z-score): Lumbar Spine − 4.1/− 2.5, Femoral Neck − 3.5/− 1.9, Total Hip − 3.4/− 2.2. Mean number of vertebral fractures 5.4 ± 2.8, history of nonvertebral fragility fracture: 83.3% (10 out of 12 patients), history of hip fracture: 16.7% (2 out of 12). EQ-5D: some degree of improvement was noted in 10 out of 12 patients (83.33%), back pain relief reported 11 out of 12 patients (91.67%). There were significant improvements (month 3 compared to baseline) for both selfreported health state (60.0 vs. 48.7) and back pain (45.6 vs. 70.8) /p b 0.05 for both comparisons/. SF-36: improvements were noted for all items, statistical significance was reached for following domains: physical functioning, pain, overall health status, vitality, functional limitation for emotional reasons and mental status /p b 0.05/.
S86
ABSTRACTS / Bone 42 (2008) S17–S110
Conclusion: We conclude that even short treatment with TPTD significantly reduces back pain (VAS), improves selfreported health status (EQ-5D-VAS) and results in improvement of quality of life in 6 out of 8 domains of the SF-36 questionnaire.
this subgroup is representative of the majority of patients usually treated for PMO. Reference [1] Chesnut CH, et al. J Bone Miner Res 2004;19:1241–9.
doi:10.1016/j.bone.2007.12.161 doi:10.1016/j.bone.2007.12.162
152 Oral ibandronate reduces non-vertebral fracture risk in postmenopausal osteoporosis: Results from a sub-analysis of a pivotal study Jacob A. Stakkestad a, Ronald Emkey b, Colin Neate c, Charles H. Chesnut d a CECOR, Haugesund, Norway b Radiant Research, Wyomissing, USA c Roche Products Limited, Welwyn Garden City, United Kingdom d Osteoporosis Research Group, University of Washington, Seattle, USA The nitrogen-containing bisphosphonate, ibandronate (Bonviva®), has proven efficacy for the treatment of postmenopausal osteoporosis (PMO). The 3-year, randomised, double-blind BONE (Bonviva Osteoporosis Trial in North America and Europe) study assessed the effect of daily (2.5 mg) or intermittent (20 mg every other day for 12 doses every 3 months) oral ibandronate versus placebo on vertebral fracture risk. The eligible participants were women (n = 2946) aged between 55– 80 years with PMO (≥ 5 years’ onset; 1–4 prevalent vertebral fractures; lumbar spine BMD T-score b − 2.0 SD). All patients received vitamin D (400IU) and oral calcium (500 mg daily). Daily ibandronate showed significant antifracture efficacy versus placebo, reducing the incidence of vertebral fractures (primary endpoint) by 62% (p = 0.0001) [1]. The study population was at relatively low risk for non-vertebral fractures, only 30.5% had a low femoral neck BMD T-score ≤ − 2.5 SD whereas N 30% had femoral neck BMD T-score N −1.6 SD at baseline. Unsurprisingly, no statistically significant effect on non-vertebral fractures was seen in the overall population, as it is not possible to detect a true reduction in fractures without appropriate fracture risk and a sufficient number of events. Therefore, a sub-analysis was carried out in 282 women at higher risk for non-vertebral fractures, who had a lumbar spine BMD T-score b −2.5 and a history of clinical fractures in the past 5 years. The results of this sub-analysis are presented here. Daily oral ibandronate reduced the risk of non-vertebral fractures to 6.2% (n = 154) versus 15.4% (n = 128) with placebo. This corresponds to a significant relative risk reduction of 62% (p = 0.025) for daily ibandronate versus placebo. These findings are consistent with a previously completed BONE study subgroup analysis in patients with similar non-vertebral fracture risk,1 which demonstrated a 69% (p = 0.012) relative risk reduction. The current analysis confirms that 2.5 mg daily oral ibandronate significantly reduces non-vertebral fracture risk versus placebo in a BONE study higher-risk subgroup. Importantly,
153 Structure activity relationships of phosphonocarboxylate inhibitors of rab geranylgeranyl transferase Charlotte A. Stewart a, Rudi Baron b, Mong S. Marma c, Katarzyna M. Blazewska c, Boris A. Kashemirov c, Frank H. Ebetino d, Charles E. McKenna c, Michael J. Rogers a, Fraser P. Coxon a a Bone Research Programme, University of Aberdeen, Aberdeen, United Kingdom b Cell and Molecular Biology, Imperial College, London, United Kingdom c Department of Chemistry, University of Southern California, Los Angeles, USA d Procter & Gamble Pharmaceuticals, Mason, USA Phosphonocarboxylates (PCs) are analogues of bisphosphonates in which one of the phosphonate groups has been replaced with a carboxylate group. We have found that these drugs have no effect on farnesyl diphosphate synthase (FPPS), but selectively inhibit a different enzyme of the mevalonate pathway, Rab geranylgeranyl transferase (RGGT), which is responsible for the prenylation of Rab GTPases. Since the first inhibitor that we identified (3-PEHPC) also inhibits bone resorption, it is likely that PCs disrupt osteoclast function by inhibiting Rab-dependent vesicular trafficking pathways in these cells. We have now compared the ability of five PCs to inhibit RGGT, disrupt Rab prenylation in cells, reduce macrophage viability and inhibit bone resorption in vitro. We found that 3-PEHPC and 3-PEPC were of similar potency (IC50 values 336 μM and 387 μM, respectively) for inhibiting RGGT in isolated enzyme assays, while 3-IPEHPC, the PC of minodronate (PG1401135) was 25–30× more potent (IC50 13 μM). The remaining 2 PCs were unable to inhibit RGGT. Similar differences were found in the ability of the PCs to inhibit Rab prenylation in J774 macrophages, while the ability of the PCs to reduce the viability of these cells also correlated with inhibition of Rab prenylation. Moreover, macrophages isolated from gunmetal mice, which have a mutation in RGGT that results in a 80% decrease in enzyme activity, were much more sensitive to 3-PEHPC and 3-IPEHPC than macrophages from heterozygous animals (in which RGGT activity is similar to wild-type animals). This strongly suggests that the cytotoxicity of the PCs is the result of inhibition of Rab prenylation. Interestingly, treatment of osteoclasts with PCs for 48 h dose-dependently caused the accumulation of large, actin-bound vacuoles, which were not seen in untreated osteoclasts. This appears to be the result of inhibition of RGGT, since only those PCs that inhibited Rab