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(tasimelteon) Capsules for Oral Administration


HETLIOZ (tasimelteon) is a melatonin receptor agonist, chemically designated as (1R, 2R)-N-[2(2,3-dihydrobenzofuran-4-yl)cyclopropylmethyl]propanamide, containing two chiral centers. The molecular formula is C15H19NO2, and the molecular weight is 245.32. The structural formula is:

HETLIOZ® (tasimelteon) Structural Formula Illustration

Tasimelteon is a white to off-white crystalline powder. It is very slightly soluble in cyclohexane, slightly soluble in water and 0.1 N hydrochloric acid, and freely soluble or very soluble in methanol, 95% ethanol, acetonitrile, isopropanol, polyethylene glycol 300, propylene glycol and ethyl acetate.

HETLIOZ is available in 20 mg strength capsules for oral administration. Inactive ingredients are: lactose anhydrous, microcrystalline cellulose, croscarmellose sodium, colloidal silicon dioxide, and magnesium stearate. Each hard gelatin capsule consists of gelatin, titanium dioxide, FD&C Blue #1, FD&C Red #3, and FD&C Yellow #6.

Last reviewed on RxList: 12/29/2014
This monograph has been modified to include the generic and brand name in many instances.

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