英文药名：Axura Filmtabletten/Lösung（memantine hydrochloride）

中文药名：盐酸美金刚片剂/溶液

生产厂家：梅尔茨制药
药品简介
新一代治疗老年性痴呆药品memantine hydrochloride（美国商品名Namen  欧洲商品名AXURA）获批准上市
阿尔茨海默氏病（Alzheimer’s disease，AD），又称老年性痴呆，是一种与衰老相关，以认知功能下降为特征的渐进性脑退行性疾病或综合症。病人整个大脑弥散性萎缩并出现明显的病理组织学改变——老年斑（senile plaque, SP）（或神经炎性斑，neuritic plaque）和神经原纤维缠结(neurofibrillary tangle, NFT)。病人认知功能下降并伴有神经元功能障碍、神经元数量减少、神经元体积扩大及突触缺失（I型营养障碍轴突）和胞内磷酸化tau（microtubule-associated protein tau）形成的成对螺旋丝，即NFT（II型营养障碍轴突）。此外，胞外的淀粉样蛋白（amyloid β-protein, Aβ）沉积形成SP，其周围环绕着营养障碍的突起。Aβ沉积形式由早期的弥散型聚集（不成熟的弥散斑）到形成成熟的致密斑，后者由直径为8nm的原纤维组成，用刚果红染色后在偏振光的照射下表现出双折射的特性。晚期的病理变化是由激活的小胶质细胞和星形胶质细胞参与的炎性反应所引起的，它们包围着沉积斑块。该病早期的行为学改变为轻微的记忆紊乱或个性改变，在5~10年内逐渐恶化，最终出现严重痴呆症状，生活不能自理。这种隐袭和破坏性的大脑退行性疾病剥夺了受害者最具人类特征的品质——记忆、推理、抽象化和语言的能力。
一、临床症状
AD几乎都是以不可觉察的方式开始发病，最初常常是偶然地、在回忆日常生活最近事件时遇到困难。病人可能无法回忆与某个人的交谈或参与过的某项活动，或者可能是对最近接受的某个项目的信息变得很迷惑，亦即以轻微认知障碍 (mild cognitive impairment，MCI)为先兆。患者往往是以纯粹的遗忘症状开始，其他认知方面很少或根本没有任何困难。MCI或早期AD患者完全保持清醒状态，没有明显的语言混乱，并保持着正常的运动和感觉功能。
AD发病的最初几年，多数病人在一般认知功能方面即已出现一些问题，例如在时间感和空间感及进行正确自如的复杂操作方面屡屡出错，并出现用词和数学运算困难等。当这些轻微的差错变得逐渐引人注意时，病人可能对一些活动和爱好变得索然无趣、出现情感淡漠、情绪不稳定了。在渐进性的记忆和认知功能衰退后，许多病人开始经历第一次、然而是比较明显的运动功能障碍，包括手工操作、写作、绘画、正常行走等。在几年或十几年的病程中，AD会逐渐恶化到明显痴呆的地步。由于定向力完全丧失、记忆力严重缺损及认知功能障碍，许多病人活动受限，被迫常常坐着或躺着，最后可能死于某些小的呼吸系统疾病，如误吸或肺炎等。
二、神经递质改变
AD脑组织中发现的第一个神经递质异常是乙酰胆碱（Ach），合成和降解Ach的酶活性发生改变。因此，AD内侧隔核和基底前脑胆碱能神经元的数量与质量都发生变化。然而，在这些递质缺乏的同时，很快伴随着其他递质神经元的减少或丧失，包括谷氨酸（Glu）、γ-氨基丁酸（GABA）、生长抑素（SST）、促肾上腺皮质激素释放因子（CRF）和5-羟色胺（5-HT）等等。因此，AD神经递质缺乏是广泛性的，并且，还没有关于各种神经元亚型遭破坏过程的清晰线索。直到现在，只有胆碱能递质功能不足被真正用于AD治疗。
**盐酸美金刚胺（memantine hydrochloride，，Namenda/Axura）——用于治疗中晚期阿尔茨海默氏病（老年性痴呆）
多奈哌齐和重酒石酸卡巴拉汀具有副作用少，老年病人容易耐受的优点；盐酸美金刚胺是美国FDA批准用于治疗中晚期阿尔茨海默氏病（老年性痴呆）的唯一药物，它的作用机制独特，是第一个在阿尔茨海默氏病和血管性痴呆方面有显著疗效的NMDA拮抗剂，当谷氨酸以病理量释放时，美金刚胺可减少谷氨酸的神经毒性作用，当谷氨酸释放过少时，美金刚胺可以改善记忆过程所需谷氨酸的传递，临床研究表明美金刚胺用于老年痴呆症患者具有较好的耐受性，在精神病理学和行为测定中产生温和的有统计学意义的显著改善，有研究表明美金刚胺与其它药物联合使用可以增加疗效，但在没有确切适应症批准之前，我们不推荐联合用药；神经节苷脂（Ganglioside，简称GM）是一种复合糖脂，存在于哺乳动物细胞，特别是神经元细胞的胞膜中，是神经细胞膜的天然组成部分，神经节苷脂能从各方面影响神经膜的功能，改善阿尔茨海默氏病（老年性痴呆）患者记忆力。
FAD日前批准/欧洲美金刚（美国商品名Namen  欧洲商品名AXURA）治疗中重度阿尔茨海默病，这也是第一个获ＦＤＡ批准可治疗较严重阿尔茨海默病的药物。美金刚为Ｎ－甲基－Ｄ－天门冬氨酸（ＮＭＤＡ）受体拮抗剂，可通过阻断谷氨酸盐的作用而缓解阿尔茨海默病患者的症状。该药物使用较为安全，最常见不良反应为眩晕（７％）、头痛（６％）和便秘（６％）。
包装规格[注：本品欧洲国家上市，不同的国家不同价格，采购以咨询为准]
瑞士上市规格
薄膜包衣片剂：
10毫克：50片.100片
20毫克：98片
混合片：（7×5毫克，7×10毫克，7×15毫克，7×20毫克）/片  28片/盒
口服溶液：溶液10毫克/克：瓶（包括计量泵。）50g.100g。

德国、英国、西班牙等国家上市的规格
以咨询为准
生产厂家：Merz Pharma AG

AXURA belongs to a group of medicines known as anti-dementia drugs.
Memory loss in Alzheimer's disease is due to disturbances in the communication signals in the brain. The brain contains so-called N-methyl D aspartate (NMDA)-petsentopi involved in the transmission of nerve signals, which are important for learning and memor
1.WHAT AXURA IS AND WHAT IT IS USED
How does Axura:
Axura belongs to a group of medicines known as anti-dementia drugs .
Memory loss in Alzheimer's disease is due to disturbances in the communication signals in the brain. The brain contains so-called N-methyl D aspartate (NMDA)- petsentopi involved in the transmission of nerve signals , which are important for learning and memory . Axura belongs to a group of drugs called antagonists of NMDA-receptor . Axura acts on these NMDA- receptors , improving the transmission of nerve signals and memory.
What to use Axura:
Axura is used for treatment of patients with moderate to severe Alzheimer's disease.
2 . BEFORE YOU TAKE AXURA
Do not take Axura
• If you are allergic ( hypersensitive) to memantine
hydrochloride or any of the other ingredients of the tablets Axura ( see section 6) .
Take special care with Axura
• If you have a history of epileptic seizures
• If you have recently had a heart attack or stroke if you have congestive heart failure or hypertension (high blood pressure).
In these situations the treatment should be carefully supervised, and the clinical benefit of Axura regularly reassessed by your doctor.
If you have renal impairment ( kidney problems) , your doctor should closely monitor your kidney function and if necessary adapt the memantine doses accordingly
The use of medicinal products amantadine (for the treatment of Parkinson's disease ) , ketamine (a substance that is normally used as an anesthetic) , dextromethorphan (normally used for treatment of cough ) and other NMDA- antagonists, should be avoided .
Axura is not recommended for children and adolescents under 18 years.
Using other medicines:
Tell your doctor if you are taking or have recently taken any other medicines, including medicines obtained without a prescription.
In particular, Axura may alter the effects of these drugs , and it may be necessary for your doctor to adjust the dose to them
- Amantadine, ketamine dextramethorphan
- Dantrolene , baclofen
- Cimetidine , ranitidine , procainamide , quinidine, quinine , nicotine
- Hydrochlorothiazide (or a combination with hydrochlorothiazide )
- Anticholinergics ( substances generally used for the treatment of movement disorders or intestinal cramps )
- Anticonvulsants (substances that are used for the prevention or treatment of seizures)
- Barbiturates (substances that are commonly used to induce sleep )
- Dopaminergic agonists (substances such as L- dopa, bromocriptine )
- Neuroleptics (substances that are used for the treatment of psychiatric disorders)
• oral anticoagulants .
If you go into hospital, let your doctor know that taking Axura.
Taking Axura with food and drink
Tell your doctor if you have recently changed or intend to change your diet ( eg from normal diet to strict vegetarian diet) or if you suffer from renal tubular acidosis ( RTA, an excess of acid-forming substances in the blood due to renal dysfunction (poor kidney function) or severe infections of the urinary system ( urinary tract ) , as may be necessary to adjust the dose of the drug.
Pregnancy and lactation
Ask your doctor or pharmacist before taking any medicine .
Tell your doctor if you are pregnant or plan to become pregnant. Memantine is not recommended for use in pregnant women.
Women taking Axura, should not breastfeed .
Driving and using machines:
Your doctor will tell you whether your illness allows you to safely drive or operate machinery.
Furthermore Axura may change your reactivity which making driving or operating machinery.
Important information about some of the ingredients of Axura:
This medicinal product contains lactose. If your doctor has warned you that you have an intolerance to some sugars, contact your doctor before taking this medicine . Your doctor will advise you how to proceed .
3 . HOW TO TAKE AXURA
Always take Axura, exactly as your doctor tells you . If you are not sure, please ask your doctor or pharmacist.
dosage
The recommended dose of Axura for adults and elderly patients is 20 mg once daily. To reduce the risk of side effects, this dose is achieved gradually by the following daily schedule:
Week 1 - half a 10 mg tablet
Week 2 - one 10 mg tablet
Week 3 - one and a half 10 mg tablet
Week 4 - 2 tablets of 10 mg once a day, and then
The usual starting dose is half a tablet once a day (1x5 mg) during the first week . This is increased to one tablet once per day (1x10 mg) in the second week to 1 and a half tablet once a day on the third week . From the fourth week on, the usual dose is 2 tablets once daily (1 x 20 mg).
Dosage in patients with impaired renal function
If you have impaired kidney function, your doctor will decide what dose is appropriate for your condition. The doctor will monitor your kidney function at regular intervals.
application
Axura should be administered orally once daily. To benefit from your medicine , you should take it regularly every day at the same time of day . The tablets should be swallowed with some water. The tablets can be taken with or without food.
Duration of treatment
Axura as long as it is of benefit to you . Your doctor should assess your treatment on a regular basis .
If you take more Axura than
• In general, taking too much Axura should not harm you . You may experience increased symptoms as described in section 4. "Possible side effects" .
• If you take Axura at a dose much higher than prescribed , contact your doctor or seek medical advice, as you may need medical help.
• If you forget to take Axura
• If you find that you forgot to take your dose Axura, wait and take your next dose at the usual time.
• Do not take a double dose to make up for a missed dose.
If you have any further questions on the use of this product, please consult your doctor or pharmacist.
4. POSSIBLE SIDE EFFECTS
Like all medicines, Axura can cause side effects, although not everybody gets them. Generally, adverse reactions were mild to moderate.
Common ( affects 1 to 10 users in 100 ):
• Headache, drowsiness , constipation , dizziness, and hypertension .
Uncommon ( affects 1 to 10 users in 1,000 ):
• Tiredness, fungal infections, confusion , hallucinations, vomiting, abnormal gait and venous blood clotting (thrombosis/thromboembolism ) .
Very rare ( affects less than 1 in 10,000 users) :
• Seizures
Not known ( can not be estimated to assess the frequency ):
• Inflammation of the pancreas and psychotic reactions. Alzheimer's disease is associated with depression , suicidal ideation and suicide attempts . These events have been reported in patients treated with Axura.
If any of the side effects gets serious , or you notice other effects not listed in this leaflet , please tell your doctor or pharmacist.
5•HOW TO STORE AXURA
• Keep out of reach of children. Do not use Axura after the expiry date stated on the carton and blister after " EXP" . Expiry date refers to the last day of that month.
This medicinal product does not require any special storage conditions .
Medicines should not be disposed of via wastewater or household waste. Consult your pharmacist how to dispose of medicines no longer required . These measures will help to protect the environment.
6 . ADDITIONAL INFORMATION
What Axura contains
The active substance is memantine hydrochloride. Each tablet contains 10 mg of memantine hydrochloride equivalent to 8,31 mg memantine.
The other ingredients are lactose monohydrate, mikrokristapinna cellulose , silica , colloidal anhydrous , magnesium stearate and talc - the core of the tablet , a copolymer of methacrylic acid - ethyl acrylate copolymer (1:1 ), sodium lauryl sulfate , polysorbate 80, talc , triacetin and simethicone emulsion - in the tablet coating .
Axura looks like and contents of the pack
Axura film-coated tablets are white to off-white, centrally tapered oblong, biconvex film-coated tablets with a single score line on both sides.