————FDA 批准了首个用于治疗亨廷顿舞蹈症的药物

美国食品与药品管理局 (FDA) 最近批准了Xenazine (丁苯那嗪) 用于治疗亨廷顿病 (Huntington’s disease) 的舞蹈症。舞蹈症是发生在患有这种疾病的人身上的不自主的抽动症状。

Xenazine 是美国 FDA 批准的可用于治疗亨廷顿病的首个药物。目前尚没有其它药物获得 FDA 批准用于治疗舞蹈症。服用 Xenazine 可能带来的严重副作用包括抑郁症和自杀倾向。因此 Xenazine 不能用于有自杀倾向的人或者没有得到治疗的抑郁症病人。

Xenazine 能够减少脑部多巴胺的量。多巴胺是一种用于神经细胞间进行信息传递的化学物质。在亨廷顿病人身上，这种信息传递过度活跃并导致身体异常运动，称为舞蹈症。Xenazine 通过减少多巴胺的量来达到减少身体不自主运动的疗效。

这种药物可以在短期内改善舞蹈症，但研究人员在临床试验中也发现，它可能会引起病人在情绪、认知、稳定性以及个体能力的恶化。因此病人在服用该药物时，医生以及病人家属需要留心病人在各个方面的表现和可能出现的副作用。

XENAZINE - 丁苯片
Lundbeck公司

xenazine®（丁苯）片，口服

最初美国批准：2008
 
警告：抑郁症与自杀

请参阅完整的处方资料完整的黑框警告。

增加抑郁症和自杀念头和行为（自杀）在亨廷顿氏症患者的风险。
抑郁症和自杀与控制考虑使用XENAZINE时choreiform运动的临床需要平衡风险。
监测患者的抑郁症，自杀倾向或行为中的不寻常的变化，出现或恶化。
告知患者，护理人员和家属的抑郁症和自杀倾向的风险，并责成报告关注的行为，及时向主治医生。
治疗病人之前，抑郁症或自杀企图或意念的历史时谨慎行事。
XENAZINE禁忌积极自杀的病人，在未经处理或处理不当的抑郁症患者。
 
适应症
XENAZINE 1囊泡单胺转运体2（VMAT）抑制剂为治疗亨廷顿氏症相关的舞蹈病表示。
 
剂量和用法
每周仔细滴定剂量的个性化要求。第一周的起始剂量是12.5毫克，每日2周，25毫克（12.5 mg，每天两次），然后慢慢滴定一个耐受剂量减少舞蹈病12.5毫克，每周一班。
最大的推荐单次剂量不超过25毫克，37.5毫克和50毫克，每天的剂量应每天分三个剂量管理。
应病人需要每天50毫克以上剂量药物代谢酶CYP2D6的基因来确定，如果病人是一个贫穷的代谢（PM）或广泛代谢（EM）的。
PMS中的最大剂量为每日25毫克的最大单剂量为50毫克。
EMS和中间代谢（IMS），最高为37.5毫克单剂量100毫克的每日最大剂量。
如果发生严重不良反应事件，滴定应该停止和的XENAXINE剂量应减少。如果不解决不良事件（S），考虑撤出的XENAZINE。

剂型和优势
12.5毫克和25毫克内服XENAZINE片（12.5毫克非入一球，25毫克得分）。
 
禁忌
XENAZINE禁忌的患者积极自杀，或有抑郁症，这是未经处理或undertreated。
XENAZINE在肝功能受损的患者禁忌。
XENAZINE禁忌患者在服用单胺氧化抑制剂或利血平。
 
注意事项：
定期重新评估的XENAZINE和潜在的不利影响，如情绪，认知，刚性和功能的能力恶化的利益。
不超过50毫克/天，最大的单剂量不应超过25毫克，如果具有较强的CYP2D6抑制剂（如氟西汀，帕罗西汀）联合管理。
抗精神病药物恶性症候群（NMS）。 停止XENAZINE如果发生这种情况。
烦躁不安，情绪激动，静坐不能和帕金森。减少剂量或停止XENAZINE如果发生这种情况。
吞咽困难及吸入性肺炎。吞咽困难的监测。
镇静/嗜睡。可能会损害病人的驾驶或操作复杂机械的能力。
酒精或其他镇静药物可加重镇静和嗜睡。
QT间期延长。没有规定延长QT间期与其他药物结合。
夸大锥体外系疾病时，使用药物，减少或拮抗多巴胺。停止XENAZINE如果发生这种情况。
 
不良反应
最常见的不良反应（> 10％，至少有5％大于安慰剂）：镇静/嗜睡，乏力，失眠，抑郁症，静坐不能，焦虑，恶心。

报告疑似不良反应，请致电1-888-882-6013或FDA在1-800-FDA-1088或www.fda.gov / medwatch XENAZINE信息中心。
 
在特殊人群中使用

妊娠：根据动物数据，，丁苯可能导致胎儿造成伤害。

日期：05/2011

XENAZINE®: 25 mg, scored tablets
(INN: tetrabenazine)
Xenazine® is indicated for the treatment of Huntington’s chorea.
GENERIC NAME: Tetrabenazine
BRAND NAME: Xenazine
How does it work?
Xenazine (Tetrabenazine) works by depleting the stores of certain chemicals called neurotransmitters within nerve cells in the brain. These neurotransmitters include dopamine, serotonin and noradrenaline and are normally involved with the passage of messages between nerve cells in the brain and the normal functioning of the brain and nervous system.
Depleting the brain of these neurotransmitters can help control movement disorders caused by diseases of the brain and nervous system, although the exact mechanism of action is not fully understood.
Xenazine (Tetrabenazine) is mainly used to control movement disorders associated with diseases of the brain and nervous system, such as Huntington's chorea, but can also be used to control movement disorders caused by antipsychotic medicines.
The older antipsychotic medicines such as chlorpromazine, haloperidol and flupentixol can cause side effects involving involuntary movement of the tongue, face, mouth and jaw, which may sometimes be accompanied by involuntary movements of the arms and legs (tardive dyskinesia). If this is disabling or socially embarrasing, and persists despite stopping or reducing the dose of the antipsychotic, the symptoms can be treated using tetrabenazine. Xenazine (Tetrabenazine) can also be used if it is not possible to stop or change the antipsychotic.
What is it used for?
Movement disorders associated with disease of the brain and spinal cord
Nerve cell breakdown resulting in irregular involuntary movements and brain disease (Huntington's chorea)
Rhythmical involuntary movement of the tongue, face, mouth and jaw, which may sometimes be accompanied by involuntary movements of the arms and legs (tardive dyskinesia)
Warning!
Do not drink alcohol whilst taking this medicine.
This medicine may cause drowsiness. If affected do not drive or operate machinery.
Not to be used in: No known conditions
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and Breastfeeding: Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
There is no information about the safety of this medicine during pregnancy, but it has been widely used for many years without apparent ill consequence.
As there is no safety information available, the manufacturer does not recommend the use of this medicine when breastfeeding. Alternatively, if this medicine must be used, the mother should not breastfeed. Seek medical advice from your doctor.
Label warnings: This medication may cause drowsiness. If affected do not drive or operate machinery. Avoid alcoholic drink.
Side effects: Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
Disturbances of the gut such as diarrhoea, constipation, nausea, vomiting or abdominal pain
Low blood pressure (hypotension)
High temperature combined with falling levels of consciousness, paleness, sweating and a fast heart beat (neuroleptic malignant syndrome). Requires stopping the medicine and immediate medical treatment.
The side effects listed above may not include all of the side effects reported by the drug's manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
Xenazine (Tetrabenazine) should not be taken at the same time as, or for 14 days following a course of monoamine oxidase inhibitor (MAOI) antidepressants, as this can cause restlessness, disorientation and confusion.
Xenazine (Tetrabenazine) opposes the effects of levodopa.
Xenazine (Tetrabenazine) should not be taken with alcohol as this may increase the drowsiness experienced.