Products
Tasimelteon was approved in the United States in 2014 and in the EU in 2015 in capsule form (Hetlioz). The drug is not currently registered in many countries.
Structure and properties
Tasimelteon (C15H19NO2, Mr = 245.3 g/mol) exists as a white crystalline powder that is sparingly soluble in water. It is structurally related to melatonin.
Effects
Tasimelteon is an agonist at the melatonin MT1 and melatonin MT2 receptors. It binds more strongly to MT2 than to MT1. These receptors are involved in the maintenance of circadian rhythms (see also under melatonin).
Indications
For the treatment of non-24-hour sleep-wake disorder (non-24). This is a sleep-wake rhythm disorder that occurs primarily in the blind. Tasimelteon is not currently approved for other indications (eg, sleep disorders, jet lag).
Dosage
According to the SmPC. The drug is taken in the evening before bedtime and always at the same time of day. It should be administered without food.
Contraindications
- Hypersensitivity
For complete precautions, see the drug label.
Interactions
Tasimelteon is metabolized by CYP1A2 and CYP3A4. Drug-drug interactions are possible with CYP1A2 inhibitors such as fluvoxamine and CYP3A4 inducers.
Adverse effects
The most common possible adverse effects include headache, nightmares, unusual dreams, elevated liver enzymes, upper respiratory tract infections, and urinary tract infections. Tasimelteon may cause drowsiness and therefore should not be taken when increased concentration is needed (e.g., before driving).
