RANKL; Rho; Ras

Zoledronic Acid (0.05 mg/kg; i.p.; weekly; for 3 weeks) increases bone mineral in terms of content and density[5].
Zoledronic Acid (0.5–1 mg/kg; intraperitoneal; weekly; for three weeks) interferes with the mechanical properties of bone by inhibiting the function of osteoblasts and osteoclasts as well as bone remodeling in vivo[5].

Cell Line: MC3T3-E1 cells Concentration: 0.01 µM , 0.1 µM, 1 µM, 10 µM, 100 µM Incubation Time: 1 day, 3 days, 5 days, 7 days Result: Reduced cells viability at 10 µM and 100 µM.

Five-week-old C57BL6 mice 0.05 mg/kg, 0.5 mg/kg, 1 mg/kg Intraperitoneal injection, weekly, for 3 weeks

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Experimental design: Five-week-old C57BL6 mice were treated with saline or ZA weekly for 3 weeks at increasing doses (0.05-1 mg/Kg). Effects of ZA on bone remodeling were studied using standard assays.[5]
Results: We observed an increase in bone mineral density and content in treated animals at doses of 0.05 mg/Kg, which was not further enhanced at higher doses of ZA. Trabecular bone volume at the proximal tibia and the distal femur assessed by histomorphometry and microCT, respectively, increased significantly in ZA-treated groups. There was however no difference between 0.5 and 1 mg/kg, suggesting a ceiling effect for ZA. ZA led to decreased numbers of osteoclasts and osteoblasts per bone perimeter that paralleled a significant reduction of serum levels of TRAC5b and osteocalcin in vivo. Effects on osteoblasts were confirmed in in vitro assays. Mechanical testing of the femur showed increased brittleness in ZA-treated mice.[5]
Conclusions: High doses of ZA inhibit both osteoclast and osteoblasts function and bone remodeling in vivo interfering with bone mechanical properties. No dose response was noted beyond 0.5 mg/kg suggesting that lower doses of ZA may be adequate in inhibiting bone resorption. Our data may help inform future studies of ZA use with respect to alternate and lower doses in the treatment of patients with cancer bone disease.[5]

Absorption, Distribution and Excretion
A 4mg intravenous dose reaches a Cmax of 370±78.5ng/mL, with a Tmax of 0.317±0.014h, and an AUC of 788±181ng\*h/mL. A 5mg intravenous dose reaches a Cmax of 471±76.1ng/mL, with a Tmax of 0.368±0.005h, and an AUC of 917±226ng\*h/mL.
Zoledronic acid is 39 ± 16% eliminated in the urine as the unmetabolized parent drug.
Zoledronic acid has a renal clearance of 3.7 ± 2.0 L/h.

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Metabolism / Metabolites
Zoledronic acid is not metabolized _in vivio_.
Zoledronate does not inhibit human P450 enzymes in vitro and does not undergo biotransformation in vivo.
Route of Elimination: In 64 patients with cancer and bone metastases, on average (± s.d.) 39 ± 16% of the administered zoledronic acid dose was recovered in the urine within 24 hours, with only trace amounts of drug found in urine post-Day 2.
Half Life: 146 hours

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Biological Half-Life
Zoledronic acid has a terminal elimination half life of 146 hours.

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Because no information is available on the use of zoledronic acid during breastfeeding, an alternate drug may be preferred, especially while nursing a newborn or preterm infant. However, absorption of zoledronic acid by a breastfed infant is unlikely.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
Zoledronic acid is 23-53% protein bound in plasma.

[1]. Various pathways of zoledronic acid against osteoclasts and bone cancer metastasis: a brief review. BMC Cancer. 2020; 20: 1059.

[2]. Zoledronate Enhances Osteocyte-Mediated Osteoclast Differentiation by IL-6/RANKL Axis. Int J Mol Sci. 2019 Mar; 20(6): 1467.

[3]. Zoledronic acid inhibits osteoclast differentiation and function through the regulation of NF-κB and JNK signalling pathways. Int J Mol Med. 2019 Aug;44(2):582-592.

[4]. Dose-dependent inhibitory effects of zoledronic acid on osteoblast viability and function in vitro. Mol Med Rep. 2016 Jan; 13(1): 613-622.

[5]. High-dose zoledronic acid impacts bone remodeling with effects on osteoblastic lineage and bone mechanical properties. Clin Cancer Res. 2009 Sep 15;15(18):5829-39.

[6]. Oral Zoledronic acid bisphosphonate for the treatment of chronic low back pain with associated Modic changes: A pilot randomized controlled trial. J Orthop Res. 2022 Feb 23.

Zoledronic acid is an imidazole compound having a 2,2-bis(phosphono)-2-hydroxyethane-1-yl substituent at the 1-position. It has a role as a bone density conservation agent. It is a member of imidazoles and a 1,1-bis(phosphonic acid).
Zoledronic acid, or CGP 42'446, is a third generation, nitrogen containing bisphosphonate similar to [ibandronic acid], [minodronic acid], and [risedronic acid]. Zoledronic acid is used to treat and prevent multiple forms of osteoporosis, hypercalcemia of malignancy, multiple myeloma, bone metastases from solid tumors, and Paget’s disease of bone. Zoledronic acid was first described in the literature in 1994. Zoledronic acid was granted FDA approval on 20 August 2001.
Zoledronic acid anhydrous is a Bisphosphonate.
Zoledronic Acid is a synthetic imidazole bisphosphonate analog of pyrophosphate with anti-bone-resorption activity. A third-generation bisphosphonate, zoledronic acid binds to hydroxyapatite crystals in the bone matrix, slowing their dissolution and inhibiting the formation and aggregation of these crystals. This agent also inhibits farnesyl pyrophosphate synthase, an enzyme involved in terpenoid biosynthesis. Inhibition of this enzyme prevents the biosynthesis of isoprenoid lipids, donor substrates of farnesylation and geranylgeranylation during the post-translational modification of small GTPase signalling proteins, which are important in the process of osteoclast turnover. Decreased bone turnover and stabilization of the bone matrix contribute to the analgesic effect of zoledronic acid with respect to painful osteoblastic lesions. The agent also reduces serum calcium concentrations associated with hypercalcemia.
Zoledronic Acid Anhydrous is anhydrous form of a synthetic imidazole third generation bisphosphonate analog of pyrophosphate with antiresorptive activity. Zoledronate binds to hydroxyapatite crystals in the bone matrix and inhibits farnesyl pyrophosphate (diphosphate) synthase, thereby preventing protein prenylation within the mevalonate pathway. This leads to the loss of downstream metabolites essential for osteoclast function, leading to the induction of apoptosis and eventually, osteoclast-cell death. By preventing osteoclast-mediated bone resorption, zoledronate decreases bone turnover and stabilizes the bone matrix.
Zoledronate (zoledronic acid, marketed by Novartis under the trade names Zometa and Reclast) is a bisphosphonate. Zometa is used to prevent skeletal fractures in patients with cancers such as multiple myeloma and prostate cancer. It can also be used to treat hypercalcemia of malignancy and can be helpful for treating pain from bone metastases.
An annual dose of Zoledronate may also prevent recurring fractures in patients with a previous hip fracture.
Zoledronate is a single 5 mg infusion for the treatment of Paget's disease of bone. In 2007, the FDA also approved Reclast for the treatment of postmenopausal osteoporosis.
An imidobisphosphonate inhibitor of BONE RESORPTION that is used for the treatment of malignancy-related HYPERCALCEMIA; OSTEITIS DEFORMANS; and OSTEOPOROSIS.

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Drug Indication
Zoledronic acid is indicated to treat hypercalcemia of malignancy, multiple myeloma, bone metastases from solid tumors, osteoporosis in men and postmenopausal women, glucocorticoid induced osteoporosis, and Paget's disease of bone in men and women. Zoledronic acid is also indicated for the prevention of osteoporosis in post menopausal women and glucocorticoid induced osteoporosis.
Prevention of skeletal-related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in adult patients with advanced malignancies involving bone. Treatment of adult patients with tumour-induced hypercalcaemia.
Prevention of skeletal related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in adult patients with advanced malignancies involving bone; treatment of adult patients with tumour-induced hypercalcaemia (TIH).
Treatment of osteoporosis: , , , in post-menopausal women; , in men; , , , at increased risk of fracture, including those with a recent low-trauma hip fracture. , , Treatment of osteoporosis associated with long-term systemic glucocorticoid therapy in post-menopausal women and in men at increased risk of fracture. , , Treatment of Paget's disease of the bone. ,
Prevention of skeletal related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in adult patients with advanced malignancies involving bone. Treatment of adult patients with tumour-induced hypercalcaemia (TIH).
4 mg / 5 ml and 4 mg / 100 ml: Prevention of skeletal-related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in adult patients with advanced malignancies involving bone. Treatment of adult patients with tumour-induced hypercalcaemia (TIH). 5 mg / 100 ml: Treatment of osteoporosis: in post-menopausal women; in men; at increased risk of fracture, including those with a recent low-trauma hip fracture. Treatment of osteoporosis associated with long-term systemic glucocorticoid therapy: in post-menopausal women; in men; at increased risk of fracture. Treatment of Paget's disease of the bone in adults.
Prevention of skeletal-related events and treatment of tumour-induced hypercalcaemia.
Prevention of skeletal related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in patients with advanced malignancies involving bone; treatment of tumour-induced hypercalcaemia (TIH); prevention of skeletal related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in patients with advanced malignancies involving bone; treatment of tumour-induced hypercalcaemia (TIH); prevention of skeletal related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in adult patients with advanced malignancies involving bone; treatment of adult patients with tumour-induced hypercalcaemia (TIH).
Prevention of skeletal related events (pathological fractures, spinal compression, radiation or surgery to bone, or tumour-induced hypercalcaemia) in adult patients with advanced malignancies involving bone. Treatment of adult patients with tumour-induced hypercalcaemia (TIH).
Treatment of osteoporosis: , , , in post-menopausal women; , in men; , , , at increased risk of fracture including those with a recent low-trauma hip fracture. , , Treatment of osteoporosis associated with long-term systemic glucocorticoid therapy: , , , in post-menopausal women; , in men; , , , at increased risk of fracture. , , Treatment of Paget's disease of the bone in adults. ,
Treatment of osteoporosisin post-menopausal womenin adult menat increased risk of fracture, including those with recent low-trauma hip fracture. Treatment of osteoporosis associated with long-term systemic glucocorticoid therapyin post-menopausal womenin adult menat increased risk of fracture. Treatment of Paget's disease of the bone in adults.
Treatment of osteoporosis, Treatment of Paget’s disease of the bone
Osteogenesis imperfecta, Prevention of fracture and bone loss in postmenopausal women with early-stage breast cancer treated with aromatase inhibitors, Prevention of skeletal related events in patients with advanced malignancies involving bone, Tumour-induced hypercalcaemia

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Mechanism of Action
Bisphosphonates are taken into the bone where they bind to hydroxyapatite. Bone resorption by osteoclasts causes local acidification, releasing the bisphosphonate, which is taken into the osteoclast by fluid-phase endocytosis. Endocytic vesicles become acidified, releasing bisphosphonates into the cytosol of osteoclasts where they act. Osteoclasts mediate resorption of bone. When osteoclasts bind to bone they form podosomes, ring structures of F-actin. Etidronic acid also inhibits V-ATPases in the osteoclast, though the exact subunits are unknown, preventing F-actin from forming podosomes. Disruption of the podosomes causes osteoclasts to detach from bones, preventing bone resorption. Nitrogen containing bisphosphonates such as zoledronate are known to induce apoptosis of hematopoietic tumor cells by inhibiting the components of the mevalonate pathway farnesyl diphosphate synthase, farnesyl diphosphate, and geranylgeranyl diphosphate. These components are essential for post-translational prenylation of GTP-binding proteins like Rap1. The lack of prenylation of these proteins interferes with their function, and in the case of Rap1, leads to apoptosis. zoledronate also activated caspases which further contribute to apoptosis.

C5H10N2O7P2

272.09

271.996

118072-93-8

Zoledronic acid monohydrate;165800-06-6;Zoledronic acid disodium tetrahydrate;165800-07-7; Zoledronic Acid;118072-93-8; 165800-06-6 (free acid hydrate); 131654-46-1 (disodium); 165800-08-8 (trisodium hydrate); 827573-11-5 (trisodium); 165800-07-7 (disodium hydrate);

68740

White to off-white solid

2.1±0.1 g/cm3

764.0±70.0 °C at 760 mmHg

193-2040ºC

415.8±35.7 °C

0.0±2.7 mmHg at 25°C

1.719

-2.28

5

8

4

16

327

0

P(C(C([H])([H])N1C([H])=NC([H])=C1[H])(O[H])P(=O)(O[H])O[H])(=O)(O[H])O[H]

XRASPMIURGNCCH-UHFFFAOYSA-N

InChI=1S/C5H10N2O7P2/c8-5(15(9,10)11,16(12,13)14)3-7-2-1-6-4-7/h1-2,4,8H,3H2,(H2,9,10,11)(H2,12,13,14)

(1-hydroxy-2-imidazol-1-yl-1-phosphonoethyl)phosphonic acid

CGP42446; CGP42446A; ZOL446; CGP-42446; CGP-42446A; ZOL-446; CGP 42446; CGP 42446A; ZOL 446; Zoledronate; Zometa; Reclast; Aclasta; (1-Hydroxy-2-(1H-imidazol-1-yl)ethane-1,1-diyl)diphosphonic acid; (1-Hydroxy-2-imidazol-1-ylethylidene)diphosphonic acid; Zoledronate, trade names: Zometa; Reclast

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Solubility in Formulation 1: 8.7 mg/mL (31.97 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution.

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Solubility in Formulation 2: 30% PEG400+0.5% Tween80+5% Propylene glycol: 10 mg/mL

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 (Please use freshly prepared in vivo formulations for optimal results.)