Hetlioz (tasimelteon)

Mechanism of Action: The mechanism by which tasimelteon exerts its therapeutic effect in patients with Non-24 or nighttime sleep disturbances in SMS is unclear. However, tasimelteon is an agonist at melatonin MT1 and MT2 receptors which are thought to be involved in the control of circadian rhythms. –Daily Med

Indications: 

• Non-24-Hour Sleep-Wake Disorder (Non-24) in adults
• Nighttime sleep disturbances in Smith-Magenis Syndrome (SMS) patients 16 years of age and older.
• Nighttime sleep disturbances in SMS in pediatric patients 3 to 15 years of age.

Some Interactions: 

• Strong CYP1A2 Inhibitors (e.g., fluvoxamine): Avoid use of HETLIOZ in combination with fluvoxamine or other strong CYP1A2 inhibitors because of a potentially large increase in tasimelteon exposure and greater risk of adverse reactions [see Clinical Pharmacology (12.3)].
• Strong CYP3A4 Inducers (e.g., rifampin): Avoid the use of HETLIOZ in combination with rifampin or other CYP3A4 inducers because of a potentially large decrease in tasimelteon exposure with reduced efficacy [see Clinical Pharmacology (12.3)].
• Beta-adrenergic Receptor Antagonists (e.g., acebutolol, metoprolol): Beta-adrenergic receptor antagonists have been shown to reduce the production of melatonin via specific inhibition of beta-1 adrenergic receptors. Nighttime administration of beta-adrenergic receptor antagonists may reduce the efficacy of HETLIOZ.

–Daily Med

Food Interactions: 

• Avoid grapefruit products. Grapefruit inhibits the CYP3A4 metabolism of tasimelteon, which may increase its serum concentration. Alternatively, the dose of tasimelteon may need to be modified.
• Avoid St. John’s Wort. This herb induces the CYP3A4 metabolism of tasimelteon and may reduce its serum concentration. Alternatively, the dose of tasimelteon may need to be modified.
• Take on an empty stomach. The Cmax of tasimelteon is reduced when taken with food.

–DrugBank

Dosing Forms: Capsules: 20 mg size 1 dark blue opaque, hard gelatin capsules printed with “VANDA 20 mg” in white. Oral suspension: 4 mg/mL white to slightly yellow opaque suspension in 48 mL or 158 mL bottles:

Usual Adult Dose for Non-24-Hour Sleep-Wake Disorder & Usual Adult Dose for SMS Sleep Disturbances:

• 20 mg orally once per day

Usual Pediatric Dose for SMS Sleep Disturbances:

• 20 mg orally once per day in patients weighing over 28 kg
• 0.7 mg/kg orally once per day in patients weighing 28 kg or less

–Hetlioz

Pros

• Not a controlled substance and is not habit-forming
• The only medication that’s approved to help people with non-24 and SMS maintain a regular sleep cycle
• Is available as a liquid medication for children with SMS.

Cons

• Needs to be taken at the SAME time every night to help the body maintain a regular sleep schedule
• Can take weeks to months for you to notice any effect depending on your sleep rhythm
• Needs to be taken on an empty stomach to help your body absorb it faster
• Has many drug interactions with other medications including rifampin, fluvoxamine, and metoprolol
• Costs/Coverage

–Good RX

Extra Notes: 

Per the rep, the PA may take 3 months and in the meantime, suggested using other medications. Expressed they couldn’t give free samples. However, that’s a LONG time to see sleep improvement. The rep tried to explain how the company won’t give weeks/month supply samples but it’s supposed to work from day one??? Have to take the dose at the SAME time EVERY night, so that’s usually not practical for shift workers.

Additional Information

Official Medication Website: Hetlioz (tasimelteon)