FDA批准新型催眠药物suvorexant

美国食品药品管理局（FDA）批准了一种新型催眠药物suvorexant（Belsomra），该药物属于食欲素受体拮抗剂。

Suvorexant是首个获批的食欲素受体拮抗剂，它通过阻断神经肽食欲素A和B与食欲素受体的结合而抑制神经元对唤醒系统的激活作用。

不过，只有在美国缉毒局（DEA）最终确定该药品是否属于管控物质后，该药品才能上市。据suvorexant生产商默克公司称，FDA建议将其列入管控物质，DEA在今年早些时候提议，按照《管控物质法》应纳入IV类管控物质之列。

默克公司预期，suvorexant将在2014年底或2015年初上市。

默克于2012年提交了批准申请。2013年5月，FDA外周与中枢神经系统药品专家委员会对该公司建议的起始剂量的安全性提出质疑。数月后，FDA建议默克公司对大多数患者的起始剂量设定为10 mg。

该公司此前没有准备生产该剂量的制剂，因此重新设计生产了几种新规格制剂。

目前，据FDA药品评价与研究中心药品评价I室主任Ellis Unger博士称，“FDA批准了4种规格——5、10、15和20 mg的Belsomra。”Unger博士在声明中指出，“使用最小有效剂量可减少副作用风险，如次日早晨的困倦。”

FDA和默克公司称，每晚仅需在睡前半小时至起床前至少7小时内服用suvorexant 1片，每天不得超过20 mg。

困倦是最常见的副作用。在FDA要求开展的次日驾驶行为研究中，服用20 mg的患者能力受损。FDA称，应警告服用20 mg的患者次日勿从事驾驶或任何需要警觉的活动。

该药物还可能导致FDA所称的“睡眠驾驶和其他在没有完全觉醒的状态下的复杂行为”，包括做饭和饮食、打电话或性行为。如果出现上述行为，患者及其家人应告知医生。

Suvorexant发放时配送一份患者用药指南，其中包括了详细的安全性信息。

FDA称，尽管针对该药开展了3项试验研究，但均未与其他已获批催眠药物进行对比研究，因此，尚不清楚该药物的对比有效性。

爱思唯尔版权所有未经授权请勿转载

By: ALICIA AULT, Internal Medicine News Digital Network

The Food and Drug Administration has approved a new type of insomnia drug, the orexin receptor antagonist suvorexant (Belsomra).

It is the first drug in the class to be approved. Suvorexant blocks the binding of orexin A and B neuropeptides to orexin receptors, presumably inhibiting activation of neurons to the arousal system.

But it will not be available until the Drug Enforcement Administration makes a final determination of where it should fit on the schedule of controlled products. The FDA recommended scheduling, and the DEA proposed earlier this year that it receive a schedule IVclassification under the Controlled Substances Act, according to suvorexant maker Merck.

The company said it expects suvorexant to be available in late 2014 or early 2015.

Merck had applied for approval in 2012. In May 2013, the FDA’s Peripheral and Central Nervous System Drugs Advisory Committee had questions about the safety of the company’s proposed starting doses. A few months later, the FDA advised Merck that it should make 10 mg the starting dose for most patients.

The company had not been prepared to manufacture that dose, so went back to work and created several new tablets.

Now, according to Dr. Ellis Unger, director of the Office of Drug Evaluation I in the FDA’s Center for Drug Evaluation and Research, "the FDA has approved Belsomra in four different strengths – 5, 10, 15, and 20 milligrams." Dr. Unger, in a statement, noted that "Using the lowest effective dose can reduce the risk of side effects, such as next-morning drowsiness."

The agency and the company say that suvorexant should only be taken once per night, within a half hour of going to bed and at least 7 hours before the person plans to wake up. Patients should not take more than 20 mg a day.

Drowsiness was the most common side effect. In FDA-required studies of next-day driving performance, patients who took 20 mg had impaired performance. Patients who take 20 mg should be warned about driving or conducting any activities that require mental alertness the next day, said the agency.

The drug also has the potential to lead to what the FDA calls "sleep-driving and other complex behaviors while not being fully awake," including preparing and eating food, making phone calls, or having sex. Patients and their families are urged to call their physician if that type of behavior is observed.

Suvorexant will be dispensed with a Medication Guide for patients that details safety information.

Although the drug was studied in three trials, none involved a comparison with other approved insomnia drugs, so its comparative effectiveness is not known, the FDA said.