ST LOUIS (MD Consult) - On May 12, 2010, the US Food and Drug Administration, along with GlaxoSmithKline, issued a notification about a new safety finding that emerged during a study of patients treated with Promacta (eltrombopag), a thrombopoietin receptor agonist.

In a study of thrombocytopenic patients with chronic liver disease of diverse etiology, patients were treated with eltrombopag 75 mg or matching placebo for 14 days before undergoing an elective invasive procedure. Six patients (4%) in the eltrombopag group and 1 (1%) in the placebo group experienced a thrombotic event of the portal venous system. Five of the six patients treated with eltrombopag experienced the portal venous thrombosis when their platelet counts exceeded 200,000/μL. On the basis of these findings, the study was terminated.

 

Promacta is indicated for the treatment of thrombocytopenia in adult patients with chronic immune (idiopathic) thrombocytopenic purpura (ITP). It is not indicated for the treatment of thrombocytopenia in patients with chronic liver disease.

The manufacturer states that treatment with Promacta should be aimed at increasing a platelet count to a level that reduces the risk of bleeding, and should not be used in an attempt to normalize a platelet count. The product should be used with caution in patients with known risk factors for thromboembolism.

In addition, clinicians should use caution when administering Promacta to patients with hepatic disease, and a lower starting dose (25 mg once daily) should be used in patients with moderate to severe liver disease. These patients should be closely monitored.

 

The manufacturer plans to conduct an in-depth analysis of data from the study in question. Furthermore, it plans to add this new safety information to Promacta's label.

圣路易斯(MD Consult)——2010年5月12日，美国食品药品管理局(FDA)联合葛兰素史克公司(GSK)发布了一则有关一项新安全性结果的通告，此结果出现在一项以促血小板生成素受体激动剂Promacta (艾曲波帕)治疗患者的研究中。

 

在对伴发慢性肝病(多种病因所致)的血小板减少症患者进行的一项研究中，行择期有创手术前以艾曲波帕 75mg或匹配的安慰剂对患者治疗了14天。艾曲波帕治疗组有6例(4%)患者、安慰剂对照组有1例(1%)患者发生了门静脉系统血栓形成事件。这6例接受艾曲波帕治疗的患者中有5例在血小板计数超过200,000/μl时发生了门静脉血栓栓塞。基于上述结果，该研究被终止。

Promacta适用于治疗成人慢性免疫性(特发性)血小板减少性紫癜(ITP)患者的血小板减少症，不适用于治疗慢性肝病患者的血小板减少症。

生产厂家声明，Promacta治疗应旨在将血小板计数增至可减少出血风险的水平，故不应该用于尝试使血小板计数恢复正常。有已知血栓形成危险因素的患者应慎用本品。

另外，医生在将Promata用于有肝病的患者时应谨慎，用于有中、重度肝病的患者时应降低该药的起始剂量(25 mg/d)，并应对这类患者进行密切监测。

生产厂家计划对受质疑的研究数据开展深入分析，此外，它还计划将这条新的安全性信息添加至Promacta的说明书中。