2013年4月23日讯 /生物谷BIOON/ --梯瓦（Teva）和Xenon制药今天宣布，FDA已授予实验性药物XEN402孤儿药地位，该药旨在发用于红斑性肢痛（erythromelalgia，EM）的治疗。
EM是一种罕见的常染色体显性遗传疾病，是肢端远端皮肤阵发性皮温升高，皮肤潮红、肿胀，并产生剧烈灼热痛为特征的一种植物神经系统疾病。环境温度升高可诱发或加剧疼痛；温度降低可使疼痛缓解。
英文原文：
Teva pain treatment gets FDA orphan drug status
Teva Pharmaceutical Industries Ltd. (NYSE: TEVA; TASE: TEVA) and Xenon Pharmaceuticals Inc. announced today that the US Food and Drug Administration (FDA) has granted orphan-drug status to the investigational drug XEN402 being developed for the treatment of pain associated with erythromelalgia (EM).
EM is a rare autosomal dominant condition characterized by debilitating spontaneous or easily evoked attacks of symmetrical burning pain in the feet and hands, typically associated with elevated skin temperature and erythema (redness of the skin). Symptoms are generally induced by exercise, prolonged standing, exposure to heat, and changes in humidity. The pain can be so severe that it can lead to suicide, and adequate treatment remains very challenging.
Orphan drug status is awarded by the FDA to novel drugs intended to treat rare diseases or conditions affecting fewer than 200,000 people in the US. This designation confers special incentives on the drug developer, including tax credits towards the cost of clinical trials, prescription drug user fee waivers and may entitle a period of seven years US market exclusivity after FDA approval.
In December 2012, Teva and Xenon signed a collaborative development and exclusive worldwide license for XEN402. Under the agreement, Teva paid Xenon an upfront fee of $41 million and will pay development, regulatory, and sales-based milestones totaling up to $335 million. Xenon is entitled to royalties payable on sales and an option to participate in commercialization in the US.
