英文药名：Zytiga(abiraterone acetate）

中文药名：醋酸阿比特龙片

品牌药生产商：Centocor公司奥托生物技术公司

药品介绍；

美国食品和药品监督管理局（FDA）批准Zytiga(abiraterone acetate，醋酸阿比特龙)与泼尼松联用治疗既往接受过多烯紫杉醇化疗的去势难治性晚期(转移性)前列腺癌患者。

男性的性激素睾丸酮能刺激前列腺肿瘤生长。药物或手术可用于减低睾丸酮生成或阻断睾丸酮的作用。但是，有时前列腺癌在睾丸酮水平很低的情况下仍可继续生长，这类肿瘤被称为去势难治性前列腺癌。

Zytiga是一种药片，作用靶点是一种被称为细胞色素P450 17A1(CYP17A1)的蛋白质，该蛋白在睾丸酮生成中起重要作用。Zytiga通过降低睾丸酮的生成来减少激素对癌细胞生长的促进作用。

FDA 通过优先审批程序批准了该药。FDA药物审评和研究中心的肿瘤药品室主任Richard Pazdur, M.D.表示：“Zytiga延长了既往接受过多种治疗的已经没有多少治疗选择的晚期前列腺癌患者的寿命”。

该批准是基于一项明确了Zytiga的安全性和有效性的临床研究结果。该研究纳入的1,195例晚期去势难治性前列腺癌既往曾接受多烯紫杉醇化疗。患者接受每天1次的Zytiga或安慰剂(糖丸)与每天2次的泼尼松治疗。

研究关注患者的总生存时间，即从治疗开始直至患者死亡的时间。接受Zytiga和泼尼松联用治疗的患者的中位生存时间为14.8个月，而接受安慰剂和泼尼松治疗患者的中位生存时间为10.9个月。

Zytiga治疗最常见的副作用包括关节肿胀或不适，低钾血症，体液潴留(脚和足常见)，肌肉不适，热潮红，腹泻，泌尿道感染，咳嗽，高血压，心跳紊乱，尿频，夜尿增加，胃不适或消化不良以及上呼吸道感染。

部分中文阿比特龙处方资料（仅供参考）

口服给药的ZYTIGA(醋酸阿比特龙)片

适应证和用途

ZYTIGA是一种CYP17抑制剂适用于与泼尼松联用为治疗既往接受含多烯紫杉醇[docetaxel]化疗转移去势难治性前列腺癌患者。

剂量和给药方法
推荐剂量：ZYTIGA1,000 mg口服给予每天1次与泼尼松联用5 mg口服给予每天2次。必须空腹服用ZYTIGA。在服用ZYTIGA 剂量前至少2小时和服用ZYTIGA剂量后至少1小时不应消耗食物。
（1）对基线中度肝受损(Child-Pugh类别B)患者，减低ZYTIGA开始剂量至250 mg每天1次.。
（2）对治疗期间发生肝毒性患者，不用ZYTIGA直至恢复。可在减低剂量再次治疗。如患者发生严重肝毒性应终止ZYTIGA。

剂型和规格
250 mg片
 
禁忌证
妊娠或可能成为妊娠妇女禁忌用ZYTIGA。

警告和注意事项
（1）盐皮质激素过量：有心血管疾病史患者谨慎使用ZYTIGA。尚未确定在有射血分量LVEF < 50%或NYHA类别III或IV心衰患者中ZYTIGA的安全性。治疗前控制高血压和纠正低钾血症。至少每月1次监查血压，血清钾和液体潴留症状。
（2）肾上腺皮质功能不全：监视肾上腺皮质功能不全的症状和征象。应急情况前，期间和后可能适应增加皮质激素剂量。
（3）肝毒性：肝酶增加曾导致药物中断，剂量调整和/或终止。监查肝功能和如建议调整，中断或终止ZYTIGA给药。
（4）食物影响：必须空腹服用ZYTIGA。当与食物同时服用醋酸阿比特龙[abiraterone acetate]阿比特龙的暴露(曲线下面积)增加达10倍。

不良反应
最常见不良反应(≥ 5%)是关节肿胀或不适，低钾血症，水肿，肌肉不适，热潮红，腹泻，泌尿道感染，咳嗽，高血压，心律失常，尿频，夜尿，消化不良，和上呼吸道感染。

为报告怀疑不良反应, 联系Centocor Ortho Biotech Inc电话 800-457-6399和www.centocororthobiotech.com或FDA电话1-800-FDA-1088或www.fda.gov/medwatch.

药物相互作用
ZYTIGA是一种肝药物代谢酶CYP2D6是抑制剂。因为治疗指数窄，避免ZYTIGA与CYP2D6底物共同给药。如果不能使用另外治疗，小心对待和考虑减低同时给予CYP2D6底物剂量。

INDICATION
ZYTIGATM (abiraterone acetate) in combination with prednisone is indicated for the treatment of patients with metastatic castration-resistant prostate cancer (CRPC) who have received prior chemotherapy containing docetaxel.

IMPORTANT SAFETY INFORMATION
Contraindications
ZYTIGATM may cause fetal harm (Pregnancy Category X) and is contraindicated in women who are or may become pregnant.

Warnings and Precautions
Hypertension, Hypokalemia and Fluid Retention Due to Mineralocorticoid Excess
Mineralocorticoid Excess - Use with caution in patients with a history of cardiovascular disease or with medical conditions that might be compromised by increases in hypertension, hypokalemia and fluid retention. Safety has not been established in patients with LVEF < 50% or NYHA Class III or IV heart failure. Control hypertension and correct hypokalemia before and during treatment. Monitor blood pressure, serum potassium, and symptoms of fluid retention at least monthly.

Adrenocortical Insufficiency
Adrenocortical Insufficiency (AI) has been reported in clinical trials after an interruption of daily steroids and/or with concurrent infection or stress. Use caution and monitor for symptoms and signs of AI if prednisone is stopped or withdrawn or if the patient experiences unusual stress. Perform appropriate tests, if indicated, to confirm AI. Increased dosages of corticosteroids may be used before, during and after stressful situations.

Hepatotoxicity
Hepatotoxicity - Increases in liver enzymes have led to drug interruption, dose modification and/or discontinuation. Monitor liver function and modify, withhold or discontinue ZYTIGATM dosing as recommended (See Prescribing Information for more information).

Food Effect
Food Effect - ZYTIGATM must be taken on an empty stomach. Exposure of abiraterone increases up to 10-fold when abiraterone acetate is taken with meals. No food should be eaten for at least two hours before the dose of ZYTIGATM is taken and for at least one hour after the dose of ZYTIGATM is taken.

Adverse Reactions
The most common adverse reactions (≥ 5%) reported in clinical trials were joint swelling or discomfort, hypokalemia, edema, muscle discomfort, hot flush, diarrhea, urinary tract infection, cough, hypertension, arrhythmia, urinary frequency, nocturia, dyspepsia and upper respiratory tract infection.

Drug Interactions
ZYTIGATM is an inhibitor of the hepatic drug-metabolizing enzyme CYP2D6. Avoid co-administration with CYP2D6 substrates that have a narrow therapeutic index. If an alternative cannot be used, exercise caution and consider a dose reduction of the CYP2D6 substrate. Additionally, abiraterone is a substrate of CYP3A4 in vitro. Strong inhibitors and inducers of CYP3A4 should be avoided or used with caution.