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：ZYTIGA 1,000 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。
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。
特殊人群中使用
在基线严重肝受损(Child-Pugh类别 C)患者中不要使用ZYTIGA。

醋酸阿比特龙脂（Zytiga）可延长前列腺癌患者生命

最近由FDA批准的用于治疗前列腺癌的一个药物，被证实是给一些患者生存时间的礼物。一项新的研究显示醋酸阿比特龙脂（Zytiga）可使最晚期前列腺癌患者的生命延长约4个月。

这个研究发表在5月的《新英格兰医学杂志》上，科罗拉多医院泌尿肿瘤科的肿瘤内科医生、科罗拉多大学医学院的助理教授ThomasW.Flaig博士是其作者之一。
ThomasW.Flaig说：“醋酸阿比特龙脂（Zytiga）是一种用于治疗晚期前列腺癌并可延长患者生命的新药。有别于用于这些疾病的传统化疗药物，醋酸阿比特龙脂（Zytiga）耐受性非常好。”
有1195名患者参与了该3期多中心临床试验，该试验着重观察了醋酸阿比特龙脂（Zytiga）和强的松联合用药对先前接受化疗的患者的有效性。在发起这项试验时，并没有明确地延长晚期前列腺癌患者生存的治疗措施。患者每天都随机接受醋酸阿比特龙脂（Zytiga）加泼尼松或安慰剂加泼尼松的治疗。该治疗持续到癌症出现进展，恶化，开始一个新的治疗或病人退出试验时。
研究表明服用醋酸阿比特龙脂（Zytiga）的患者生存时间比服用安慰剂的患者延长约4个月的时间。此外，接受醋酸醋酸阿比特龙脂（Zytiga）治疗的患者中PSA水平显著下降的人数多于服用安慰剂的患者。
ThomasW.Flaig说：“在这项研究中观察到的对于生存的益处，尤其值得注意，因为这是在前列腺癌最晚期的病例中发现的。有其他研究正在检验应用醋酸阿比特龙脂（Zytiga）对较早期患者的益处，这种情况下可能会更加有效。”

FDA在4月底批准了醋酸阿比特龙脂（Zytiga）。片剂有很少的副作用，但仍需小心的监测潜在的副作用，包括肝功能血清学指标的变化、低血钾、腿部肿胀和高血压。

ZYTIGA® APPROVED IN THE EUROPEAN UNION FOR METASTATIC CASTRATION-RESISTANT PROSTATE CANCER
First once-daily, oral treatment inhibits androgen production at all sources
Beerse, Belgium, September 7, 2011 /PRNewswire/ — Janssen-Cilag International NV announced today that, after an accelerated regulatory review process by the European Medicines Agency (EMA) and following a positive CHMP opinion on the 22 July 2011, the European Commission has approved the marketing authorisation for ZYTIGA® (abiraterone acetate), a novel, once-daily, oral, androgen biosynthesis inhibitor. Abiraterone acetate is approved, in combination with prednisone or prednisolone, for the treatment of metastatic castration-resistant prostate cancer (mCRPC) in adult men whose disease has progressed on or after a docetaxel-based chemotherapy regimen.1

"The European Commission approval of abiraterone acetate gives new hope to men who are suffering from this late stage of prostate cancer with very few treatment options left," said Professor Karim Fizazi, Department of Cancer Medicine, Institut Gustave Roussy, France, who was an investigator in the abiraterone acetate pivotal Phase 3 study. "The efficacy, safety and ease of use of abiraterone acetate, a medicine that can be taken at home, will address an important unmet medical need for many patients, helping them to live longer with a better quality of life and less pain."

Abiraterone acetate is an androgen biosynthesis inhibitor that inhibits the CYP17 enzyme complex which is required for the production of androgens.1 Androgens (e.g. testosterone) are hormones that promote the development and maintenance of male sex characteristics.2 However, in prostate cancer, androgens can fuel the tumour’s growth.3 Androgen production primarily occurs in the testes and adrenal glands but, in men with prostate cancer, the tumour tissue is an additional source of androgens.1 Abiraterone acetate is the first oral treatment for metastatic castration-resistant prostate cancer that inhibits androgen production at all three sources.1

Results of the pivotal Phase 3, randomised, placebo-controlled, multicentre study showed that at a pre-specified interim analysis, after a follow-up of 12.8 months, treatment with abiraterone acetate in combination with prednisone or prednisolone resulted in a 35.4 percent reduction in the risk of death [hazard ratio (HR) = 0.65; 95 percent CI: 0.54, 0.77; p<0.001] and an improvement of 3.9 months in median overall survival (14.8 months vs. 10.9 months) compared to placebo plus prednisone or prednisolone.4 In an updated analysis (with follow-up period of 20.2 months), results were consistent with those from the interim analysis with a 4.6 month improvement in median overall survival between the two arms (15.8 months vs. 11.2 months [HR = 0.74]) in favour of abiraterone acetate. The effect of abiraterone acetate and prednisone on overall survival was consistent across all subgroups.4

In patients who reported significant pain from their disease (a baseline pain score of 4 or more using the Brief Pain Inventory-Short Form [BPI-SF] scale of 0 to 10) and with at least one post-baseline pain score, the percentage experiencing pain relief (at least a 30% reduction from baseline in the BPI-SF worst pain intensity score over 24 hours without any increase in analgesic usage score observed at two consecutive eva luations four weeks apart) was higher in the abiraterone acetate group than in the placebo group (44% versus 27%, p=0.002).4

A lower proportion of patients receiving abiraterone acetate had skeletal related events compared with those given placebo (18% vs 28% at six months, 30% vs 40% at 12 months and 35% vs 40% at 18 months).1 A skeletal related event was defined as a pathological fracture (a broken bone caused by disease weakening the bone), spinal cord compression, palliative radiation to bone (used to lessen bone pain), or surgery to bone.4

"In patients who have exhausted standard treatment options, including chemotherapy, abiraterone acetate offers a novel, well tolerated option for treating this devastating disease,” explained Professor Johann S. de Bono, MD, FRCP, MSc, PhD, The Institute of Cancer Research, The Royal Marsden NHS Foundation Trust, and one of the co-lead investigators for the Phase 3 clinical study. “In Europe, prostate cancer is the third most common cause of cancer deaths so it is essential that new treatments options like abiraterone acetate are developed."

Overall, compliance with abiraterone acetate treatment was high, and side effects were easily manageable and reversible, despite the advanced age and level of frailty of the study population.4 The most common adverse reactions seen with abiraterone acetate are peripheral oedema, hypokalaemia, hypertension and urinary tract infection.1

Abiraterone acetate should be taken once a day on an empty stomach, at least two hours after eating, and no food should be eaten for at least one hour after taking the tablets.1