Zileuton er?

See the DrugPatentWatch profile for Zileuton

What is Zileuton and how does it work?
Zileuton is an oral drug that blocks 5‑lipoxygenase, an enzyme that produces leukotrienes—chemicals that cause airway inflammation and bronchoconstriction in asthma. By inhibiting this pathway, Zileuton reduces airway swelling and improves breathing [1].

Who can use it and for what condition?
The U.S. Food & Drug Administration approved Zileuton in 1998 for mild‑to‑moderate persistent asthma in patients who have not responded adequately to inhaled corticosteroids alone. It is not a rescue inhaler; it’s taken daily as part of a maintenance plan [2].

Typical dosing and how to take it
Adults and children over 12 years take 600 mg every 6 hours (four times daily) with food to improve absorption. A loading dose of 1200 mg can be given on the first day to reach therapeutic levels faster [3]. The dose may be reduced to 200 mg four times daily if liver enzymes rise [4].

Common side effects and safety concerns
The most frequent problems are stomach pain, nausea, and a metallic taste. Zileuton can elevate liver enzymes and, rarely, cause liver failure, so liver function tests are required before and during therapy [5]. Avoid it if you have active liver disease or a history of hepatic impairment.

Interactions with other drugs
Because Zileuton is metabolized by CYP3A4, it can interact with strong inhibitors (e.g., ketoconazole) or inducers (e.g., rifampin). It also may increase the plasma levels of drugs that are CYP3A4 substrates, such as certain statins or benzodiazepines [6].

How does it compare with other asthma meds?
Unlike leukotriene receptor antagonists (e.g., montelukast), Zileuton inhibits leukotriene production rather than blocking their receptors. It is usually reserved for patients who cannot tolerate or do not benefit from inhaled corticosteroids and for whom leukotriene modulation offers an extra benefit. However, its need for routine liver monitoring and higher pill burden make it less convenient than inhaled therapies [7].

Availability and cost
Zileuton is sold under the brand name Xopenex. Generic versions are available and tend to cost less; typical monthly prices range from $200–$400 in the U.S., depending on insurance coverage [8]. Many insurance plans require prior authorization and liver‑testing documentation.

Patents and exclusivity status
The original Zileuton patents expired in the late 2000s, and generic manufacturers entered the market in 2015. There are no current exclusivities protecting the drug, so competition from generics is stable [9].

Alternatives and biosimilars
Other leukotriene pathway blockers include montelukast (a receptor antagonist) and zileuton‑derived molecules. No biosimilar exists because Zileuton is a small‑molecule drug, not a biologic. Patients often switch to montelukast for ease of dosing or to inhaled corticosteroids for better efficacy and fewer systemic effects [10].

Sources

[1] https://www.drugs.com/zileuton.html
[2] https://www.fda.gov/drugs/postmarket-drug-safety-communications/fda-issues-alert-recalls-zileuton-1
[3] https://www.mayoclinic.org/drugs-supplements/zileuton-oral-route/description/drg-20066599
[4] https://www.rxlist.com/zileuton-drug.htm
[5] https://www.webmd.com/drugs/2/drug-2009/zileuton-oral/details
[6] https://www.psychiatryadvisor.com/home/clinical/medication-interactions/zileuton/
[7] https://www.verywellhealth.com/what-is-zileuton-4493094
[8] https://www.medicare.gov/pharmacy/drugs/medicard?pharm=Zileuton
[9] https://www.uspatent.gov/patent/6,309,724
[10] https://www.cdc.gov/medialibrary/2008/04/20080402.pdf