HCV NS3 protease(Ki=14 nM)
Boceprevir (EBP-520; SCH-503034): Targets hepatitis C virus (HCV) NS3 protease; it shows potent inhibitory activity with a Ki value of 14 nM in enzyme assay and an EC₉₀ value of 0.35 μM in cell-based replicon assay. It also exhibits high selectivity, with a 2200-fold higher inhibitory effect against HCV NS3 protease compared to human neutrophil elastase (HNE) [1]
- Boceprevir (EBP-520; SCH-503034): Targets HCV NS3/4A protease; it can inhibit the activity of NS3/4A protease in transgenic mouse models, thereby reducing the secretion of Gaussia luciferase (Gluc) into the plasma [2]

体外活性：在 HCV NS3 蛋白酶连续测定中，Boceprevir (SCH 503034) 的平均 Ki 值为 14 nM。在 HuH-7 细胞中进行 72 小时双顺反子亚基因组细胞复制子测定时，EC50 和 EC90 值分别确定为 0.20 µM 和 0.35 µM。 Boceprevir 还被发现是一种非常弱的 HNE 抑制剂 (Ki=26 µM)，选择性为 2200。 激酶测定：Boceprevir 是一种新型、有效、高选择性、口服生物可利用的 HCV NS3 蛋白酶抑制剂，两种药物的 Ki 均为 14 nM基于细胞的复制子测定中酶测定和 EC90 为 350 nM。细胞测定：J774A.1细胞（鼠巨噬细胞系）以5×104个细胞/孔接种在96多孔板中，在补充有10%胎牛血清（FBS）的RPMI培养基中培养24小时。将细胞用大肠杆菌 0111:B4 LPS (1 μg/ml) 引发 4 小时，然后用 ATP (5 mM) 引发 30 分钟，以诱导 NLRP3 炎性体形成。收集上清液并使用小鼠 IL-1β ELISA 试剂盒测量 IL-1β 水平。为了测试 16673-34-0 对 NLRP3 炎性体激活的抑制作用，在 ATP 时与 16673-34-0 (400μM) 或格列本脲 (400μM) 共同处理细胞 30 分钟，IL-1β 水平为用作读出。

---

酶活及细胞水平抑制活性：博赛泼维（Boceprevir, EBP-520; SCH-503034） 是HCV NS3蛋白酶的强效抑制剂。在酶活实验中，其Ki值为14 nM，表明对靶点酶具有强结合亲和力；在细胞复制子实验中，展现出显著的抗病毒活性，EC₉₀值为0.35 μM。此外，它对HCV NS3蛋白酶具有高选择性，对该病毒蛋白酶的抑制活性是人中性粒细胞弹性蛋白酶（HNE）的2200倍，有助于降低潜在的脱靶效应[1]
- 细胞转染实验中的活性验证：将pBI-NS3/4A质粒（携带NS3/4A基因）与pTet-On-rtTA、pBI-Cre质粒共转染至CHO细胞，同时以单独转染pBI-NS3/4A质粒作为对照。转染6小时后，用多西环素（Dox，1 μg/mL）处理细胞，48小时后收获细胞。通过检测细胞裂解液中的萤火虫荧光素酶（Fluc）活性和培养基中的Gluc活性，验证该系统的功能性。随后，在该体外系统中加入博赛泼维，可观察到培养基中Gluc活性降低，表明其能抑制NS3/4A蛋白酶活性，证实了其在体外对NS3/4A蛋白酶的抑制作用[2]

Boceprevir 是一种 HCV 蛋白酶抑制剂，用于治疗 HCV 感染。博普瑞韦的药代动力学特征在多种动物物种中进行了评估。口服给药后，Boceprevir 在大鼠（10 mg/kg）、狗（3 mg/kg）和猴子（3 mg/kg）中被中等程度吸收。狗的吸收相对较快，但小鼠 (10 mg/kg)、大鼠和猴子的吸收较慢，平均吸收时间 (MAT) 范围为 0.5 至 1.4 小时即可证明。狗和大鼠的 AUC 较高，小鼠的 AUC 适中，猴子的 AUC 较低。小鼠、大鼠和狗的绝对口服生物利用度较低（26-34%），但猴子的绝对口服生物利用度较低（4%）。 Boceprevir（100 mg/kg，口服）可抑制三重转基因小鼠中的 HCV NS3/4A 蛋白酶活性。

---

三重转基因小鼠模型中的活性：构建条件诱导型NS3/4A/Lap/LC-1三重转基因小鼠模型。给小鼠饮用含Dox（1 mg/mL Dox + 50 g/L蔗糖）的水3天，诱导NS3/4A蛋白酶表达，此时小鼠血浆Gluc活性较未诱导小鼠升高70倍。对经Dox诱导的三重转基因小鼠，口服给予博赛泼维（Boceprevir, EBP-520; SCH-503034）（100 mg/kg，每日两次，从Dox诱导第3天开始，持续7天），与DMSO处理对照组相比，血浆Gluc活性降低65%。该结果表明博赛泼维在体内可有效抑制转基因小鼠肝脏中的NS3/4A蛋白酶活性[2]
- HCV复发肝移植患者中的疗效：在5例基因型1型HCV复发的肝移植患者中，经过4周导入期后，给予博赛泼维（Boceprevir, EBP-520; SCH-503034） 800 mg，每日三次，联合聚乙二醇干扰素（PegIFN）和利巴韦林（RBV）治疗，同时联用免疫抑制剂（3例用环孢素，2例用他克莫司，1例用依维莫司）。在平均14.8±3.1周的随访期内，所有患者均出现病毒学应答：基线时平均HCV病毒载量（HVL）为6.87±0.70 log₁₀ IU/mL，至第12周时，平均HVL下降6.64±0.35 log₁₀ IU/mL，显示出在该特定患者群体中显著的体内抗病毒疗效[3]
- 不同人群中的疗效差异：在基因型1型慢性HCV感染治疗中，博赛泼维（Boceprevir, EBP-520; SCH-503034） 联合PegIFN和RBV的三联疗法，相比标准双联疗法（PegIFN+RBV）显著提高了持续病毒学应答（SVR）率。标准双联疗法SVR率仅为40%-50%，而含博赛泼维的三联疗法可将SVR率提升至70%。但在非洲裔美国人基因型1型慢性HCV患者中，临床试验显示其接受博赛泼维三联疗法的SVR率低于白人患者，且可能需要更长的治疗疗程才能达到与白人患者相当的SVR率[4, 5]

pBI-NS3/4A转基因体外功能验证[2]
中国仓鼠卵巢（CHO）细胞在添加了10%胎牛血清的RPMI-1640培养基中培养。通过与pTet-On和pBI-G//Cre质粒共转染来测试pBI-NS3/4A的功能。为了实现这一点，根据制造商的方案，使用Lipofectamine 2000试剂转染CHO细胞。共转染6小时后，用含有1μg/mL Dox的新鲜培养基替换培养基，并诱导48小时。随后，分别收集细胞培养基和细胞，通过生物发光成像（BLI）检测萤光素酶活性，并通过蛋白质印迹分析检测萤光素素酶表达。

---

HCV NS3蛋白酶活性检测实验：
1. 酶与底物制备：分离纯化HCV NS3蛋白酶，获得具有活性的酶蛋白；制备模拟NS3蛋白酶天然切割位点的肽底物，底物可标记可检测基团（如荧光基团），便于活性检测。
2. 反应体系构建：在适宜的反应缓冲液中，将纯化的NS3蛋白酶与不同浓度的博赛泼维（Boceprevir, EBP-520; SCH-503034） 混合，在特定温度（如37°C）下孵育一定时间，使抑制剂与酶充分结合。
3. 底物加入与检测：向反应体系中加入制备好的肽底物，继续孵育；使用检测仪器（如荧光酶标仪）监测底物标记基团信号（如荧光强度）随时间的变化，反映底物的切割情况。
4. 数据分析：根据检测到的信号变化，计算不同博赛泼维浓度下的酶活性；采用合适的动力学模型拟合数据，确定博赛泼维对NS3蛋白酶的Ki值（14 nM），评估其对酶的抑制 potency[1]
- 人中性粒细胞弹性蛋白酶（HNE）选择性检测实验：
1. HNE与底物制备：获取人中性粒细胞弹性蛋白酶，制备HNE特异性底物（同样标记可检测基团用于活性测定）。
2. 反应与检测：构建含HNE和不同浓度博赛泼维（Boceprevir, EBP-520; SCH-503034） 的反应体系，孵育后加入HNE底物，采用与NS3蛋白酶检测相同的方法，通过测定底物标记基团信号变化检测酶活性。
3. 选择性计算：比较博赛泼维对HCV NS3蛋白酶和HNE的抑制浓度，计算抑制50% HNE活性所需浓度与抑制50% NS3蛋白酶活性所需浓度的比值，得到2200倍的选择性比例，证实博赛泼维对病毒蛋白酶的高选择性[1]

HCV复制子细胞实验：
1. 细胞培养：培养HCV复制子细胞（稳定含HCV复制子、可在细胞内独立复制的细胞）于含必需营养物质和抗生素的适宜培养基中，维持细胞生长及复制子稳定性。
2. 药物处理：将复制子细胞以适宜密度接种于96孔板，贴壁后向培养基中加入不同浓度的博赛泼维（Boceprevir, EBP-520; SCH-503034），同时设溶剂对照组（如DMSO）；在37°C、5% CO₂培养箱中孵育特定时间（如72小时），使药物发挥作用。
3. 病毒复制检测：采用适宜的RNA提取方法提取细胞总RNA，通过实时定量逆转录聚合酶链反应（qRT-PCR）检测细胞内HCV RNA水平，以管家基因（如GAPDH）为内参校正RNA上样量。
4. 数据分析：计算各博赛泼维处理组相对于对照组的HCV RNA相对水平，通过剂量-效应曲线拟合确定抑制90%病毒复制的药物浓度（EC₉₀=0.35 μM），评估其体外抗病毒活性[1]
- NS3/4A蛋白酶活性CHO细胞共转染实验：
1. 细胞制备：培养CHO细胞至对数生长期，调整细胞密度至适宜浓度（如1×10⁵ cells/mL）以备转染。
2. 转染操作：采用转染试剂将pBI-NS3/4A质粒（含NS3/4A基因及带NS3/4A切割位点的Gluc报告基因）与pTet-On-rtTA（表达rtTA蛋白）、pBI-Cre（表达Cre重组酶）质粒共转染至CHO细胞，同时设单独转染pBI-NS3/4A质粒的对照组。
3. 诱导与药物处理：转染6小时后，向培养基中加入Dox（1 μg/mL），诱导Cre和NS3/4A蛋白表达；同时向实验组加入不同浓度的博赛泼维（Boceprevir, EBP-520; SCH-503034），细胞继续孵育48小时。
4. 活性检测：收集细胞培养基，采用Gluc检测试剂盒和发光仪测定Gluc活性；裂解细胞制备细胞裂解液，检测Fluc活性以验证Cre介导的重组效率；对细胞裂解液用抗NS3/4A抗体进行Western blot分析，确认NS3/4A蛋白表达；对浓缩后的培养基用抗Gluc抗体进行Western blot分析，检测Gluc分泌情况；通过比较药物处理组与对照组的Gluc活性，分析博赛泼维对NS3/4A蛋白酶活性的影响[2]

Mice
Triple-transgenic mice (n = 5 per group) are induced with Doxycycline (Dox) for 10 days in order to assess the impact of Boceprevir. The mice receive oral gavage twice daily for seven days with either Boceprevir (100 mg/kg) or DMSO after plasma Gluc activity peaks on the third day following Dox induction. Every day during this time, blood is drawn from the caudal vein in order to measure plasma Gluc activity.

---

Using triple-transgenic mice to evaluate the effects of NS3/4A inhibitors[2]
Telaprevir and boceprevir were used. To evaluate the effect of telaprevir, triple-transgenic mice were randomized into two groups (n = 5 per group) and administered either telaprevir (200 mg/kg) or vehicle (dimethyl sulfoxide, DMSO) via oral gavage twice daily for 10 days. At the same time, the mice were continuously induced with Dox (1 mg/mL Dox and 50 g/L sugar were dissolved in their drinking water).
To evaluate the effect of boceprevir, triple-transgenic mice were induced with Dox for 10 days (n = 5 per group). On the third day after Dox induction, when plasma Gluc activity reached its peak, the mice were administered either boceprevir (100 mg/kg) or DMSO via oral gavage twice daily for 7 days. During this period, blood was collected from the caudal vein daily to detect plasma Gluc activity.[2]

---

In vivo efficacy evaluation in triple-transgenic mice:
1. Mouse preparation: Use NS3/4A/Lap/LC-1 triple-transgenic mice (containing rtTA, Cre, and NS3/4A transgenes). Maintain the mice under specific pathogen-free (SPF) conditions with a 12-hour light/dark cycle and free access to food and water.
2. Dox induction: Dissolve Dox (1 mg/mL) and sugar (50 g/L) in the drinking water of the triple-transgenic mice to induce NS3/4A protease expression. Continue the induction for 3 days, with non-induced triple-transgenic mice and wild-type (WT) mice as controls.
3. Drug administration: On the 3rd day of Dox induction, divide the induced triple-transgenic mice into two groups: the Boceprevir (EBP-520; SCH-503034) treatment group and the DMSO control group. Administer Boceprevir orally via gavage at a dose of 100 mg/kg twice daily for 7 days; the control group receives the same volume of DMSO. During the drug treatment period, continue the Dox induction by providing Dox-containing drinking water.
4. Sample collection and detection: Collect blood samples from the caudal vein of the mice daily to separate plasma. Measure the Gluc activity in the plasma using a Gluc detection kit and a luminometer to monitor the inhibitory effect of Boceprevir on NS3/4A protease activity in real time. After the treatment, sacrifice the mice, collect liver tissue, and perform Western blot analysis with anti-NS3 antibody to confirm NS3/4A protein expression, and histological examination to assess liver tissue changes [2]

Absorption, Distribution and Excretion
Boceprevir reaches peak plasma concentration 2 hours after administration. Absolute bioavailability has not been determined. When taken with food exposure increases up to 65%. In capsule, Boceprevir consists of two diaseromers in a 1:1 ratio. In plasma this ratio changes to 2:1 favoring the active diastereomer.
Boceprevir is mainly eliminated in the feces (79%) with a small amount eliminated in the urine (9%). Approximately 8% and 3% is excreted as the parent compound in the feces and urine respectively.
The mean apparent volume of distribution for Bocepravir is 772 litres at steady state.
Boceprevir has a mean total body clearance of 161 liters per hour.
In healthy subjects who received 800 mg three times daily alone, boceprevir drug exposure was characterized by AUC(T) of 5408 ng. hr per mL (n=71), Cmax of 1723 ng per mL (n=71), and Cmin of 88 ng per mL (n=71). Pharmacokinetic results were similar between healthy subjects and HCV-infected subjects.
Boceprevir was absorbed following oral administration with a median Tmax of 2 hours. Steady state AUC, Cmax, and Cmin increased in a less-than-dose-proportional manner and individual exposures overlapped substantially at 800 mg and 1200 mg, suggesting diminished absorption at higher doses. Accumulation is minimal (0.8- to 1.5-fold) and pharmacokinetic steady state is achieved after approximately 1 day of three times daily dosing.
Boceprevir should be administered with food. Food enhanced the exposure of boceprevir by up to 65% at the 800 mg three times daily dose, relative to the fasting state. The bioavailability of boceprevir was similar regardless of meal type (e.g., high-fat vs. low-fat) or whether taken 5 minutes prior to eating, during a meal, or immediately following completion of the meal. Therefore, boceprevir may be taken without regard to either meal type or timing of the meal.
Boceprevir has a mean apparent volume of distribution (Vd/F) of approximately 772 L at steady state in healthy subjects.
For more Absorption, Distribution and Excretion (Complete) data for Boceprevir (10 total), please visit the HSDB record page.

---

Metabolism / Metabolites
Bocepravir is primarily metabolized via the aldo-ketoreductase-mediated pathway producing a diastereomeric mix of metabolites at a 4 fold greater exposure than the parent compound. Boceprevir also undergoes oxidative metabolism via CYP3A4/5, although to a lesser extent.
Studies in vitro indicate that boceprevir primarily undergoes metabolism through the aldo-ketoreductase (AKR)-mediated pathway to ketone-reduced metabolites that are inactive against HCV. After a single 800-mg oral dose of (14)C-boceprevir, the most abundant circulating metabolites were a diasteriomeric mixture of ketone-reduced metabolites with a mean exposure approximately 4-fold greater than that of boceprevir. Boceprevir also undergoes, to a lesser extent, oxidative metabolism mediated by CYP3A4/5.

---

Biological Half-Life
Boceprevir has a mean half-life of elimination of 3.4 hours.
Boceprevir is eliminated with a mean plasma half-life (t1/2) of approximately 3.4 hours.

---

Effect on oral clearance of immunosuppressive agents: In liver transplant patients with HCV recurrence, when Boceprevir (EBP-520; SCH-503034) (800 mg three times a day) is co-administered with immunosuppressive agents (IT), it inhibits cytochrome P450 3A enzyme, thereby reducing the oral clearance of IT. The mean estimated oral clearance of cyclosporine decreases by approximately 50%, that of tacrolimus decreases by up to 80%, and that of everolimus decreases by 52% compared to when IT is administered alone. This indicates that Boceprevir affects the metabolism of these immunosuppressive agents by inhibiting the relevant metabolic enzyme [3]

Hepatotoxicity
In large randomized controlled trials, triple therapy with boceprevir, peginterferon and ribavirin was associated with a high rate of adverse events that often required dose adjustments and led to early discontinuation in 5% to 20% of patients. However, serum ALT elevations and clinically apparent liver injury were not generally mentioned as adverse events of therapy. The exception to this occurred in patients with preexisting cirrhosis in whom de novo, seemingly spontaneous hepatic decompensation occurred in a proportion of treated subjects. The cause of the decompensation was not clear and the separate role of boceprevir from peginterferon and ribavirin and from what might happen even without therapy could not be easily defined. Nevertheless, in postmarketing studies of triple therapy of chronic hepatitis C with cirrhosis, decompensation was reported in 3% to 8% of patients and deaths from hepatic failure in 1% to 3%.
Likelihood score for the combination of boceprevir, peginterferon and ribavirin: B (likely cause of liver injury and hepatic decompensation in patients with preexisting cirrhosis or advanced fibrosis).

---

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Boceprevir has been removed from the US market. It has not been studied in nursing mothers being treated for hepatitis C infection. Because it must be used with ribavirin and peginterferon alfa, it is not considered a good choice during breastfeeding. Until more data become available, an alternate drug may be preferred, especially while nursing a newborn or preterm infant.
Hepatitis C is not transmitted through breastmilk and breastmilk has been shown to inactivate hepatitis C virus (HCV). However, the Centers for Disease Control recommends that mothers with HCV infection should consider abstaining from breastfeeding if their nipples are cracked or bleeding. It is not clear if this warning would apply to mothers who are being treated for hepatitis C.
Infants born to mothers with HCV infection should be tested for HCV infection; because maternal antibody is present for the first 18 months of life and before the infant mounts an immunologic response, nucleic acid testing is recommended.
◉ 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.

---

Protein Binding
Bocepravir is approximately 75% bound to human plasma proteins following a single dose.

---

Hematological toxicity in liver transplant patients: In five liver transplant patients treated with Boceprevir (EBP-520; SCH-503034) combined with PegIFN and RBV, all patients developed anemia. The mean hemoglobin level decreased from 13.18 ± 1.18 g/dL at baseline to 10.4 ± 1.5 g/dL at week 12, with a mean decrease of 3.12 ± 2.27 g/dL. All five patients required administration of β-erythropoietin to alleviate anemia; three patients needed a reduction in ribavirin dose (by 33%-75%), and one patient required a blood transfusion due to a hemoglobin level dropping below 8 g/dL. This suggests that the combination therapy including Boceprevir may induce hematological toxicity, mainly manifested as anemia [3]
- Drug-drug interactions: Boceprevir (EBP-520; SCH-503034) inhibits cytochrome P450 3A enzyme, leading to drug-drug interactions when co-administered with immunosuppressive agents metabolized by this enzyme (such as cyclosporine, tacrolimus, everolimus). As a result, the plasma concentrations of these immunosuppressive agents increase due to reduced oral clearance, which may increase the risk of adverse effects related to immunosuppressive agents. Therefore, dose adjustments of immunosuppressive agents are necessary when co-administered with Boceprevir [3]

[1]. Challenges in modern drug discovery: a case study of boceprevir, an HCV protease inhibitor for the treatment of hepatitis C virus infection. Acc Chem Res. 2008 Jan;41(1):50-9.

[2]. Conditional Inducible Triple-Transgenic Mouse Model for Rapid Real-Time Detection of HCV NS3/4A ProteaseActivity. PLoS One. 2016 Mar 4;11(3):e0150894.

[3]. Practical management of boceprevir and immunosuppressive therapy in liver transplant recipients with hepatitis C virus recurrence. Antimicrob Agents Chemother. 2012 Nov;56(11):5728-34.

[4]. New developments in the management of hepatitis C virus infection: focus on boceprevir. Biologics. 2012;6:249-56.

[5]. Telaprevir and boceprevir in african americans with genotype 1 chronic hepatitis C: implications for patients and providers. South Med J. 2012 Aug;105(8):431-6.

Boceprevir is a synthetic tripeptide consisting of N-(tert-butylcarbamoyl)-3-methyl-L-valyl, a cyclopropyl-fused prolyl and 3-amino-4-cyclobutyl-2-oxobutanamide residues joined in sequence. Used for treatment of chronic hepatitis C virus genotype 1 infection. It has a role as a hepatitis C protease inhibitor, a peptidomimetic and an antiviral drug. It is a tripeptide and a member of ureas.
Boceprevir is a direct acting antiviral medication used as part of combination therapy to treat chronic Hepatitis C, an infectious liver disease caused by infection with Hepatitis C Virus (HCV). HCV is a single-stranded RNA virus that is categorized into nine distinct genotypes, with genotype 1 being the most common in the United States, and affecting 72% of all chronic HCV patients. Treatment options for chronic Hepatitis C have advanced significantly since 2011, with the development of Direct Acting Antivirals (DAAs) such as Boceprevir. Boceprevir is an inhibitor of NS3/4A, a serine protease enzyme, encoded by HCV genotypes 1 and 4 [synthesis]. These enzymes are essential for viral replication and serve to cleave the virally encoded polyprotein into mature proteins like NS4A, NS4B, NS5A and NS5B. The barrier for develoment of resistance to NS3/4A inhibitors is lower than that of NS5B inhibitors, another class of DAAs. Subtitutions at amino acid positions 155, 156, or 168 are known to confer resistance. The substitutions of the enzyme's catalytic triad consisting of H58, D82, and S139 are also likely to alter the affinity of the drug for NS3/4A or the activity of the enzyme itself. Despite this disadvantage Boceprevir is still effective against HCV when paired with [DB00811], [DB00008], and [DB00022]. In a joint recommendation published in 2016, the American Association for the Study of Liver Diseases (AASLD) and the Infectious Diseases Society of America (IDSA) do not reccomend Boceprevir in combination with [DB00811], [DB00008], and [DB00022] as first line therapy for Hepatitis C. Boceprevir, [DB00811], [DB00008], and [DB00022] are used with the intent to cure, or achieve a sustained virologic response (SVR), after 48 weeks of daily therapy. SVR and eradication of HCV infection is associated with significant long-term health benefits including reduced liver-related damage, improved quality of life, reduced incidence of Hepatocellular Carcinoma, and reduced all-cause mortality. Boceprevir is available as a fixed dose product (tradename Victrelis) used for the treatment of chronic Hepatitis C. Approved in May 2011 by the FDA, Victrelis is indicated for the treatment of HCV genotype 1 in combination with [DB00811], [DB00008], and [DB00022]. Victrelis is no longer widely used as interferon-free therapies have been developed.
Boceprevir is a Hepatitis C Virus NS3/4A Protease Inhibitor. The mechanism of action of boceprevir is as a HCV NS3/4A Protease Inhibitor, and Cytochrome P450 3A4 Inhibitor, and Cytochrome P450 3A5 Inhibitor.
Boceprevir is an oral, direct acting hepatitis C virus (HCV) protease inhibitor that was used in combination with peginterferon and ribavirin in the treatment of chronic hepatitis C, genotype 1. Initially approved for use in 2012, it was withdrawn in 2015 because of the availability of more effective and better tolerated all oral regimens of direct acting antiviral agents. Boceprevir was not linked to instances of acute liver injury during therapy but, when combined with peginterferon and ribavirin, was associated with cases of hepatic decompensation in patients with preexisting cirrhosis.
Boceprevir is an orally bioavailable, synthetic tripeptide inhibitor of the nonstructural protein 3 and 4A complex (NS3/NS4A), with potential activity against hepatitis C virus (HCV) genotype 1. Upon administration, boceprevir reversibly binds to the active center of the HCV NS3/NS4A and prevents NS3/NS4A protease-mediated polyprotein maturation. This disrupts the processing of viral proteins and the formation of a viral replication complex, which inhibits viral replication in HCV genotrype 1-infected host cells. NS3, a serine protease, is essential for the proteolytic cleavages within the HCV polyprotein and plays a key role during HCV viral RNA replication. NS4A is an activating factor for NS3. HCV is a small, enveloped, single-stranded RNA virus belonging to the Flaviviridae family.

---

Drug Indication
Boceprevir, when used in combination with [DB00811], [DB00008], and [DB00022] is indicated for use in the treatment of chronic HCV genotype 1 infection in adults.
FDA Label
Victrelis is indicated for the treatment of chronic hepatitis-C (CHC) genotype-1 infection, in combination with peginterferon alfa and ribavirin, in adult patients with compensated liver disease who are previously untreated or who have failed previous therapy.
Treatment of chronic hepatitis C

---

Mechanism of Action
Boceprevir is a NS3/4a protease inhibitor used to inhibit viral HCV replication. NS3/4a protease is an integral part of viral replication and mediates the cleavage the virally encoded polyprotein to mature proteins (NS4A, NS4B, NS5A and NS5B). Boceprevir covalently but reversibly binds the serine (S139) resiude in the active site via a (α)-ketoamide functional group. This inhibits the proteolytic acitvity of the HCV 1a and 1b encoded enzyme.
Boceprevir is a selective hepatitis C virus (HCV) nonstructural (NS) 3/4A protease inhibitor. The drug is a direct-acting antiviral agent with activity against HCV. Boceprevir contains an alpha-ketoamide functional group that selectively, covalently, and reversibly binds the active serine site of HCV NS3 protease. By blocking proteolytic cleavage of NS4A, NS4B, NS5A, and NS5B from the HCV-encoded polyprotein, the drug inhibits HCV replication in host cells. Boceprevir has in vitro activity against HCV genotypes 1a and 1b, but is less active against genotypes 2, 2a, and 3a.
Boceprevir is an inhibitor of the HCV NS3/4A protease that is necessary for the proteolytic cleavage of the HCV encoded polyprotein into mature forms of the NS4A, NS4B, NS5A and NS5B proteins. Boceprevir covalently, yet reversibly, binds to the NS3 protease active site serine (S139) through an (alpha)-ketoamide functional group to inhibit viral replication in HCV-infected host cells. In a biochemical assay, boceprevir inhibited the activity of recombinant HCV genotype 1a and 1b NS3/4A protease enzymes, with Ki values of 14 nM for each subtype.
... Boceprevir is a ketoamide protease inhibitor that binds reversibly to the HCV nonstructural NS3 protease active site inhibiting intracellular viral replication. Phase III clinical studies have demonstrated that, in combination with the current standard of care, boceprevir significantly increases the a sustained virological response rate in both treatment-naive and previously treated patients with genotype 1 CHC. ...

---

Drug discovery and design process: Boceprevir (EBP-520; SCH-503034) was developed through a structure-based drug design approach. Since no lead compounds were obtained from initial screening, an α-ketoamide-type electrophile was designed to covalently bind to the serine hydroxyl group of HCV NS3 protease, thereby inhibiting enzyme activity. Early ketoamide inhibitors mimicked the structure of peptide substrates of NS3 protease. With the assistance of X-ray crystallography, the lead compound was gradually optimized: starting from an undecapeptide with a molecular weight of 1265 Da, it was stepwise truncated to a tripeptide with a molecular weight of 500 Da. To reduce the peptidic nature of the inhibitor, strategies such as replacing amide bonds with hydrazine urea and macrocyclization at P2-P4 and P1-P3 positions were explored. Further optimization of the tripeptide inhibitor identified the optimal moieties for each site: primary ketoamide at P', cyclobutylalanine at P1, gem-dimethylcyclopropylproline at P2, tert-leucine at P3, and tert-butyl urea as the capping group. The combination of these moieties led to the discovery of Boceprevir, which entered clinical development [1]
- Clinical development status: Boceprevir (EBP-520; SCH-503034) was well-tolerated in phase I clinical trials and demonstrated antiviral activity. At the time of the literature publication, it was in phase II clinical trials for the treatment of HCV infection [1]. Later, it was approved by the US Food and Drug Administration (FDA) for clinical use as a triple therapy with PegIFN and RBV for genotype 1 chronic HCV infection, marking an important advancement in HCV treatment [4, 5]
- Treatment regimen considerations: In the treatment of HCV recurrence in liver transplant patients, Boceprevir (EBP-520; SCH-503034) is administered at a dose of 800 mg three times a day, starting after a 4-week lead-in phase of PegIFN/RBV therapy. Due to its interaction with immunosuppressive agents, close monitoring of the plasma concentrations of immunosuppressive agents is required during co-administration, and the doses of these agents should be reduced (e.g., a 50% reduction in cyclosporine dose, a more significant reduction in tacrolimus dose) to avoid excessive immunosuppression and related adverse effects [3]
- Efficacy in specific populations: In African American patients with genotype 1 chronic HCV infection, although Boceprevir (EBP-520; SCH-503034)-based triple therapy improves SVR rates compared to the standard dual therapy, their SVR rates are still lower than those in white patients. Clinical evidence suggests that African American patients may need a longer duration of Boceprevir-containing therapy to achieve the same SVR rate as white patients. However, due to the small number of African American patients included in early clinical trials, further studies with larger sample sizes are needed to accurately evaluate the efficacy of Boceprevir in this population and provide more targeted treatment recommendations [5]

C27H45N5O5

519.68

519.342

C, 62.40; H, 8.73; N, 13.48; O, 15.39

394730-60-0

Boceprevir-d9;1256751-11-7

10324367

Off-white to pale yellow solid powder

1.2±0.1 g/cm3

1.533

2.05

150.7

4

5

10

37

959

4

O=C(N1[C@@H]([C@@]2([H])C(C)([C@]2(C1)[H])C)C(NC(C(C(N)=O)=O)CC3CCC3)=O)[C@@H](NC(NC(C)(C)C)=O)C(C)(C)C

LHHCSNFAOIFYRV-DOVBMPENSA-N

InChI=1S/C27H45N5O5/c1-25(2,3)20(30-24(37)31-26(4,5)6)23(36)32-13-15-17(27(15,7)8)18(32)22(35)29-16(19(33)21(28)34)12-14-10-9-11-14/h14-18,20H,9-13H2,1-8H3,(H2,28,34)(H,29,35)(H2,30,31,37)/t15-,16?,17-,18-,20+/m0/s1

(1R,2S,5S)-N-(4-amino-1-cyclobutyl-3,4-dioxobutan-2-yl)-3-((S)-2-(3-(tert-butyl)ureido)-3,3-dimethylbutanoyl)-6,6-dimethyl-3-azabicyclo[3.1.0]hexane-2-carboxamide

EBP 520; EBP-520; EBP520; SCH-503034; SCH503034; SCH 503034; trade name: Victrelis;

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)

DMSO : 16.67 ~100 mg/mL ( 32.08~192.42 mM )
H2O : < 0.1 mg/mL
Ethanol : ~100 mg/mL

配方 1 中的溶解度: ≥ 1.67 mg/mL (3.21 mM) (饱和度未知) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (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 16.7 mg/mL澄清的DMSO储备液加入到400 μL PEG300中，混匀；再向上述溶液中加入50 μL Tween-80，混匀；然后加入450 μL生理盐水定容至1 mL。
*生理盐水的制备：将 0.9 g 氯化钠溶解在 100 mL ddH₂O中，得到澄清溶液。

---

配方 2 中的溶解度: 1.67 mg/mL (3.21 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (这些助溶剂从左到右依次添加，逐一添加), 悬浊液; 超声助溶。
例如，若需制备1 mL的工作液，可将 100 μL 16.7mg/mL澄清的DMSO储备液加入到900μL 20％SBE-β-CD生理盐水中，混匀。
*20% SBE-β-CD 生理盐水溶液的制备（4°C，1 周）：将 2 g SBE-β-CD 溶解于 10 mL 生理盐水中，得到澄清溶液。

---

View More

配方 3 中的溶解度: ≥ 1.67 mg/mL (3.21 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 16.7 mg/mL 澄清 DMSO 储备液加入到 900 μL 玉米油中并混合均匀。

---

配方 4 中的溶解度: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: ≥ 1.67 mg/mL (3.21 mM)

---

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。