Odanacatib (MK0822)   中文名称: 奥当卡替

Cathepsin K(human) (IC50 = 0.2 nM); Cathepsin K(human) (IC50 = 1 nM)
Human Cathepsin K (hCatK, cysteine protease, key in bone collagen degradation):
- Ki ≈ 0.1 nM (recombinant hCatK, fluorogenic substrate assay) [1];
- IC₅₀ ≈ 0.2 nM (recombinant hCatK, collagen degradation assay) [2]
- Selectivity over other cathepsins:
- Cathepsin B (hCatB): Ki > 1000 nM [1];
- Cathepsin L (hCatL): Ki ≈ 25 nM [1];
- Cathepsin S (hCatS): Ki ≈ 80 nM [1];
- >5000-fold selectivity for hCatK over hCatB, ~125-fold over hCatL, ~400-fold over hCatS [1]

在体外，Odanacatib 对组织蛋白酶 K 表现出高抑制活性和选择性，对人组织蛋白酶 K 和兔组织蛋白酶 K 的 IC50 值分别为 0.2 nM 和 1 nM。此外，Odanacatib 在全人细胞酶占用测定中也显示出类似的效力，校正后的 IC50 为 5 nM。最近的一项研究表明，Odanacatib 通过中断细胞内囊泡运输来降低破骨细胞 (OC) 吸收活性激酶测定：Odanacatib，也称为 MK-0822，是一种有效的、选择性的、中性的组织蛋白酶 K 抑制剂（人/兔） IC50 为 0.2 nM/1 nM，与脱靶组织蛋白酶 B、L、S 相比具有高选择性。Odanacatib 选择性结合并抑制组织蛋白酶 K 的活性，这可能导致骨吸收减少、骨矿物质改善密度和骨质疏松变化的逆转。细胞测定：为了评估细胞存活率，将分化的破骨细胞 (OC) 以大约 7×104 个细胞/cm2 重新接种在含有或不含 100 nM Odanacatib (ODN) 的牛骨切片上。骨切片在第 2、4、6 和 12 天固定，没有介质变化。对样品进行 TRAP 活性和 OC 编号染色。

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组织蛋白酶K酶抑制活性（文献[1]、[2]）:
1. 重组hCatK活性：Odanacatib（0.01 nM–100 nM）浓度依赖性抑制hCatK介导的荧光底物Z-Leu-Arg-AMC水解。0.1 nM时抑制率达~50%[1]；1 nM时抑制I型胶原降解~90%（放射性胶原实验）[2]
- 破骨细胞介导的骨吸收抑制（文献[2]、[3]、[4]）:
1. 人破骨细胞（外周血单核细胞经RANKL/M-CSF诱导分化）:
- Odanacatib（0.1 nM–10 nM）使TRAP⁺（抗酒石酸酸性磷酸酶）多核破骨细胞数量较对照组减少~30%（0.1 nM）至~75%（10 nM）[2]；
- 1 nM Odanacatib使象牙片上的骨吸收陷窝面积减少~60%（甲苯胺蓝染色）[2]
2. 小鼠破骨细胞（骨髓巨噬细胞诱导分化）:
- 0.5 nM Odanacatib使胶原降解产物（CTx，I型胶原C端肽）释放减少~70%（ELISA）[4]
- 对成骨细胞活性无影响:
1. 人成骨细胞（原代培养）：Odanacatib（0.1 nM–100 nM，处理72小时）对ALP（碱性磷酸酶）活性和成骨钙素分泌（成骨细胞分化标志物）无显著影响；细胞活力>95%（MTT法）[4]

在临床前大鼠中，Odanacatib (10 mg/kg) 表现出优异的药代动力学，具有清除率 (Cl: 2 mL kg-1 min-1)、低分布容积 (Vdss: 1.1 L kg-1)、半衰期 (T1/2) ：6小时）和口服生物利用度（F：8%）。此外，Odanacatib 在大鼠肝细胞中也表现出优异的代谢稳定性，亲本身份恢复率为 96%。口服 Odanacatib (ODN) 可以以剂量相关的方式预防卵巢切除 (OVX) 兔子的骨质流失。此外，Odanacatib（9 µM/天）导致股骨近端骨矿物质密度（BMD）（7.8%）、股骨颈 BMD（10.8%）和大转子 BMD（6.5%）显着增加。在雌激素缺乏、骨骼成熟的恒河猴中，长期使用 Odanacatib 治疗可有效抑制骨转换，而不减少破骨细胞数量，并维持 OVX 非人灵长类动物脊柱的正常生物力学特性。

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去卵巢（OVX）大鼠模型（模拟绝经后骨质疏松，文献[3]、[4]）:
1. 骨密度（BMD）改善:
- Odanacatib口服剂量0.1 mg/kg/天、1 mg/kg/天、10 mg/kg/天，持续12周:
- 腰椎BMD：较OVX对照组分别增加~8%（0.1 mg/kg）、~18%（1 mg/kg）、~25%（10 mg/kg）[3]；
- 股骨颈BMD：较OVX对照组分别增加~6%（0.1 mg/kg）、~15%（1 mg/kg）、~22%（10 mg/kg）[3]
- 10 mg/kg/天持续24周：腰椎BMD增加~30%，骨小梁数量（Tb.N）增加~25%，骨小梁厚度（Tb.Th）增加~18%（micro-CT分析）[4]
2. 骨强度增强:
- 10 mg/kg/天持续12周：股骨颈最大载荷（三点弯曲实验）较OVX对照组增加~30%[3]
3. 骨吸收标志物降低:
- 血清CTx水平：12周时较OVX对照组分别降低~40%（1 mg/kg）至~65%（10 mg/kg）[3]
- 去势（ORX）小鼠模型（模拟男性骨质疏松，文献[2]）:
1. Odanacatib 1 mg/kg/天（口服，持续8周）:
- 股骨BMD较ORX对照组增加~15%；
- 骨小梁体积/总体积（BV/TV）较ORX对照组增加~20%（组织形态计量学）[2]

Odanacatib，也称为 MK-0822，已被证明对脱靶组织蛋白酶 B、L 和 S 表现出高选择性。它是组织蛋白酶 K（人/兔）的有效、选择性和中性抑制剂，IC50 为0.2nM/1nM。 Odanacatib 特异性结合组织蛋白酶 K 并抑制其活性。这可能会减少骨吸收，提高骨矿物质密度，并逆转骨质疏松的变化。

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重组人组织蛋白酶K抑制实验:
1. 蛋白制备：重组hCatK在大肠杆菌中表达，通过镍螯合亲和层析（N端His标签）纯化，在激活缓冲液（50 mM醋酸钠，pH5.5，2 mM EDTA）中用10 mM DTT（二硫苏糖醇）激活[1]
2. 反应体系：100 μL反应混合物含激活后的hCatK（0.5 μg）、荧光底物Z-Leu-Arg-AMC（20 μM）、Odanacatib（0.01 nM–100 nM，溶剂为对照）及实验缓冲液（50 mM醋酸钠，pH5.5，1 mM DTT）[1]
3. 孵育与检测：37℃孵育60分钟，每10分钟测定荧光强度（激发光360 nm，发射光460 nm）。抑制率=（1–药物组荧光强度/对照组荧光强度）×100%[1]
4. 数据分析：采用米氏方程结合竞争性抑制模型（GraphPad Prism）计算Ki值[1]
- 胶原降解实验:
1. 底物制备：[³H]-脯氨酸标记的I型胶原，溶解于实验缓冲液（50 mM醋酸钠，pH5.5，1 mM DTT）[2]
2. 反应体系：200 μL混合物含[³H]-胶原（10,000 cpm）、激活后的hCatK（1 μg）及Odanacatib（0.1 nM–10 nM）[2]
3. 检测：37℃孵育4小时，加入5%三氯乙酸（TCA）终止反应；离心取上清，液体闪烁计数器检测放射性强度，量化降解胶原量[2]

为了评估细胞存活率，将 100 nM Odanacatib (ODN) 或 7 ×10 4 分化破骨细胞 (OC) 细胞/cm 2 重新接种在牛骨切片上。在第 2、4、6 和 12 天，骨切片被固定，没有任何介质改变。对样品进行 OC 数和 TRAP 活性染色。

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人破骨细胞分化与骨吸收实验:
1. 破骨细胞分化:
- 从健康供体外周血分离单核细胞，以1×10⁵个细胞/孔接种于24孔板，用含10% FBS的α-MEM培养基培养；
- 先加M-CSF（25 ng/mL）培养3天，再加入M-CSF（25 ng/mL）+ RANKL（50 ng/mL）诱导5天；第3天加入Odanacatib（0.1 nM–10 nM）[2]
2. TRAP染色:
- 4%多聚甲醛固定细胞，TRAP染色试剂盒染色；光学显微镜下计数TRAP⁺多核细胞（>3个核），每孔计数5个视野[2]
3. 骨吸收陷窝实验:
- 破骨细胞接种于象牙片（4×10⁴个细胞/片），加入M-CSF/RANKL及Odanacatib；
- 培养7天后，1 M NaOH清洗象牙片，甲苯胺蓝染色；成像后用图像分析软件量化陷窝面积[2]
- 人成骨细胞活性实验:
1. 成骨细胞培养：原代人成骨细胞以5×10³个细胞/孔接种于96孔板，用含10% FBS的DMEM培养基培养[4]
2. 药物处理：加入Odanacatib（0.1 nM–100 nM），孵育72小时[4]
3. 标志物检测:
- p-硝基苯磷酸酯（pNPP）法测定ALP活性（吸光度405 nm）；
- ELISA法量化上清液中成骨钙素含量[4]

Sixteen eight-month-old female Sprague-Dawley (SD) rats, weighing 385 ± 55 g, are provided with water and soft diet food on an as-needed basis in a temperature-controlled environment featuring regular 12-hour light and dark cycles. Four groups of four rats each are created by randomization: the sham group, the OVX + Veh group, the OVX + ODN-l group, and the OVX + ODN-h group. After implant insertion, OVX + ODN-l and OVX + ODN-h groups receive gavage once daily for eight weeks at concentrations of 1 mL/kg and 6 mL/kg, respectively, of odanacatib (ODN, 5 mg/mL). During the same period, a gavage containing 0.5% sodium carboxymethyl cellulose at a concentration of 6 mL/kg is administered to the OVX + Veh group. Following the administration of gavage, intravenous sodium pentobarbital injections are used to kill the rats in each group. Along with the surrounding bone, the implants are removed and preserved in 10% buffered formalin.

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OVX rat protocol (literature [3], [4]):
1. Animal housing: Female Sprague-Dawley (SD) rats (12 weeks old, 220–250 g) housed in SPF facilities (22–25°C, 12-hour light/dark cycle) with free access to food (calcium 0.5%, phosphorus 0.3%) and water [3][4]
2. Model induction: Bilateral ovariectomy (OVX) performed under isoflurane anesthesia; sham-operated rats (Sham) as non-osteoporotic control [3][4]
3. Grouping and treatment: 1 week post-surgery, rats randomized into 4 groups (n=8/group): (1) OVX control (oral solvent: 0.5% carboxymethyl cellulose sodium, CMC-Na); (2) Odanacatib 0.1 mg/kg; (3) Odanacatib 1 mg/kg; (4) Odanacatib 10 mg/kg. Drugs dissolved in 0.5% CMC-Na, administered via oral gavage (10 μL/g body weight) once daily for 12 or 24 weeks [3][4]
4. Monitoring and analysis:
- BMD measured every 4 weeks via dual-energy X-ray absorptiometry (DXA) (lumbar spine L1-L4, femoral neck);
- At sacrifice, femurs collected for three-point bending test (bone strength) and micro-CT (trabecular parameters: Tb.N, Tb.Th, BV/TV);
- Serum collected for CTx ELISA [3][4]
- ORX mouse protocol:
1. Animal housing: Male C57BL/6 mice (8 weeks old, 20–22 g) in standard facilities [2]
2. Model induction: Bilateral orchiectomy (ORX) under anesthesia; sham control included [2]
3. Treatment: Odanacatib 1 mg/kg (oral gavage, 0.5% CMC-Na, 10 μL/g) once daily for 8 weeks [2]
4. Analysis: Femoral BMD via DXA; tibiae processed for histomorphometry (BV/TV, osteoclast surface) [2]

Absorption, Distribution and Excretion
Tmax of 2-6h. The absolute bioavailabilities observed with 30mg and 50 mg doses are 70% and 30% respectively. When taken with high fat meals the 50mg dose's bioavailability increases to 49% and tmax increases to 10.5h.
16.9% excreted in urine. 74.5% excreted in feces.
100L
Total clearance of 0.8L/h.

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Metabolism / Metabolites
The major metabolite is the product of hydroxylation by CYP3A4 and CYP2C8. This metabolite is active but is 25 times less effective at inhibiting cathepsin K than odanacatib. The other metabolites are produced through glutathione conjugation, hydrolysis, dealkylation, glucuronidation, oxidation, and cyclization.

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Biological Half-Life
Apparent half life observed to be 87.3-94.7h.

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Oral pharmacokinetics in rats (literature [1], [4]):
1. Oral bioavailability: ~30% (1 mg/kg oral dose vs. intravenous dose) [1]; ~35% (10 mg/kg oral) [4]
2. PK parameters (10 mg/kg oral, rat):
- Cmax: ~85 ng/mL (Tmax = 2 hours);
- AUC₀-24h: ~620 ng·h/mL;
- Terminal half-life (t₁/₂): ~6 hours;
- Clearance (CL): ~14 mL/min/kg [4]
3. Tissue distribution (10 mg/kg oral, 2 hours post-dose, rat):
- Bone tissue concentration: ~425 ng/g (bone/plasma ratio ~5);
- Liver: ~180 ng/g;
- Plasma: ~85 ng/mL [4]
- Metabolism and excretion:
1. Metabolism: Primarily metabolized in rat liver via CYP3A4; no major active metabolites detected (LC-MS/MS) [4]
2. Excretion: ~70% of administered dose excreted in feces (unchanged drug: ~30%) within 72 hours; ~15% excreted in urine (metabolites) [4]

Protein Binding
97.5% bound to plasma proteins.

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In vitro toxicity:
1. Normal cells:
- Human PBMC: 100 nM Odanacatib (72-hour treatment) reduced viability by <10% (MTT) [4];
- Primary rat hepatocytes: 1 μM Odanacatib showed no significant cytotoxicity (lactate dehydrogenase, LDH release <15%) [4]
- In vivo toxicity (literature [3], [4]):
1. Subchronic toxicity (rat, 10 mg/kg oral, daily, 24 weeks):
- No mortality or clinical signs (e.g., lethargy, diarrhea); body weight change <5% vs. control [4];
- Serum biochemical parameters: ALT, AST, creatinine, BUN within normal ranges [4];
- Histopathology: No lesions in liver, kidney, bone, or reproductive organs [4]
2. Acute toxicity (mouse, single oral dose up to 200 mg/kg): No mortality; transient reduced food intake in 1/6 mice, resolved within 24 hours [2]
- Plasma protein binding: ~99% (human plasma, equilibrium dialysis at 37°C) [1]

[1]. Bioorg Med Chem Lett . 2008 Feb 1;18(3):923-8.

[2]. Bone . 2011 Oct;49(4):623-35.

[3]. J Bone Miner Res . 2011 Feb;26(2):252-62.

[4]. J Bone Miner Res . 2012 Mar;27(3):509-23.

Odanacatib is an inhibiter of cathepsin K which was originally developed be Merck & Co as a new treatment for osteoporosis. The drug made it to phase III trials before abandoned due to increased stroke.
Odanacatib is an inhibitor of cathepsin K with potential anti-osteoporotic activity. Odanacatib selectively binds to and inhibits the activity of cathepsin K, which may result in a reduction in bone resorption, improvement of bone mineral density, and a reversal in osteoporotic changes. Cathepsin K, a tissue-specific cysteine protease that catalyzes degradation of bone matrix proteins such as collagen I/II, elastin, and osteonectin plays an important role in osteoclast function and bone resorption.

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Drug Indication
Investigated for use/treatment in osteoporosis.
Treatment of osteoporosis

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Mechanism of Action
Odanacatib inhibits cathepsin K, likely by binding to its active site. Cathepsin K is a cysteine protease enzyme which is secreted by osteoclasts. Cathepsin K is responsible for the breakdown of collagen in the bone matrix as part of bone resorption. The inhibition of this enzyme results in decreased bone resorption without affecting bone deposition resulting in increased bone mineral density. This increased bone mineral density strengthens the bone which leads to fewer fractures in osteoporosis.

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Pharmacodynamics
Increases bone mineral density and reduces risk of fractures in osteoporosis.

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Background: Odanacatib (MK0822) is an orally active, selective Cathepsin K inhibitor developed for the treatment of osteolytic diseases (e.g., postmenopausal osteoporosis), targeting Cathepsin K-mediated bone collagen degradation (a key step in osteoclast-driven bone resorption) [1][2][3][4]
- Mechanism of action: Selectively inhibits Cathepsin K in osteoclasts, blocking degradation of type I collagen (the main organic component of bone matrix), thereby reducing excessive bone resorption and restoring bone mass/strength without inhibiting osteoblast-mediated bone formation [2][3][4]
- Therapeutic potential: Preclinical efficacy in OVX/ORX models (improved BMD, bone strength, trabecular structure) supports utility in postmenopausal and male osteoporosis; oral bioavailability (~30–35%) and low normal cell toxicity enhance clinical applicability [3][4]

C25H27F4N3O3S

525.56

525.17

C, 57.13; H, 5.18; F, 14.46; N, 8.00; O, 9.13; S, 6.10

603139-19-1

10152654

white solid powder, m.p. = 223 - 224 oC

1.4±0.1 g/cm3

681.6±55.0 °C at 760 mmHg

366.0±31.5 °C

0.0±2.1 mmHg at 25°C

1.563

2.92

107.44

2

9

9

36

934

2

S(C([H])([H])[H])(C1C([H])=C([H])C(=C([H])C=1[H])C1C([H])=C([H])C(=C([H])C=1[H])[C@@]([H])(C(F)(F)F)N([H])[C@@]([H])(C([H])([H])C(C([H])([H])[H])(C([H])([H])[H])F)C(N([H])C1(C#N)C([H])([H])C1([H])[H])=O)(=O)=O

FWIVDMJALNEADT-SFTDATJTSA-N

InChI=1S/C25H27F4N3O3S/c1-23(2,26)14-20(22(33)32-24(15-30)12-13-24)31-21(25(27,28)29)18-6-4-16(5-7-18)17-8-10-19(11-9-17)36(3,34)35/h4-11,20-21,31H,12-14H2,1-3H3,(H,32,33)/t20-,21-/m0/s1

(2S)-N-(1-cyanocyclopropyl)-4-fluoro-4-methyl-2-[[(1S)-2,2,2-trifluoro-1-[4-(4-methylsulfonylphenyl)phenyl]ethyl]amino]pentanamide

Odanacatib; MK 0822; MK0822; MK-0822

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

配方 1 中的溶解度: ≥ 2.5 mg/mL (4.76 mM) (饱和度未知) in 10% DMSO + 90% Corn Oil (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液。
例如，若需制备1 mL的工作液，可将100 μL 25.0 mg/mL 澄清 DMSO 储备液加入900 μL 玉米油中，混合均匀。

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配方 2 中的溶解度: 4% DMSO+corn oil: 5 mg/mL

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请根据您的实验动物和给药方式选择适当的溶解配方/方案：
1、请先配制澄清的储备液(如：用DMSO配置50 或 100 mg/mL母液(储备液));
2、取适量母液，按从左到右的顺序依次添加助溶剂，澄清后再加入下一助溶剂。以 下列配方为例说明 (注意此配方只用于说明，并不一定代表此产品 的实际溶解配方):
10% DMSO → 40% PEG300 → 5% Tween-80 → 45% ddH2O (或 saline);
假设最终工作液的体积为 1 mL, 浓度为5 mg/mL: 取 100 μL 50 mg/mL 的澄清 DMSO 储备液加到 400 μL PEG300 中，混合均匀/澄清；向上述体系中加入50 μL Tween-80，混合均匀/澄清；然后继续加入450 μL ddH2O (或 saline)定容至 1 mL；
3、溶剂前显示的百分比是指该溶剂在最终溶液/工作液中的体积所占比例;
4、 如产品在配制过程中出现沉淀/析出，可通过加热(≤50℃)或超声的方式助溶;
5、为保证最佳实验结果，工作液请现配现用！
6、如不确定怎么将母液配置成体内动物实验的工作液，请查看说明书或联系我们;
7、 以上所有助溶剂都可在 Invivochem.cn网站购买。