ZAFIRLUKAST tablet coated

Country: United States

Language: English

Source: NLM (National Library of Medicine)

Active ingredient:

ZAFIRLUKAST (UNII: XZ629S5L50) (ZAFIRLUKAST - UNII:XZ629S5L50)

Available from:

Avera McKennan Hospital

INN (International Name):

ZAFIRLUKAST

Composition:

ZAFIRLUKAST 20 mg

Prescription type:

PRESCRIPTION DRUG

Authorization status:

New Drug Application

Summary of Product characteristics

ZAFIRLUKAST- ZAFIRLUKAST TABLET, COATED
AVERA MCKENNAN HOSPITAL
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ZAFIRLUKAST TABLETS
DESCRIPTION
Zafirlukast is a synthetic, selective peptide leukotriene receptor
antagonist (LTRA), with the chemical
name
4-(5-cyclopentyloxy-carbonylamino-1-methyl-indol-3-ylmethyl)-3-methoxy-N-o-
tolylsulfonylbenzamide. The molecular weight of zafirlukast is 575.7
and the structural formula is:
The empirical formula is: C
H N O S
Zafirlukast, a fine white to pale yellow amorphous powder, is
practically insoluble in water. It is
slightly soluble in methanol and freely soluble in tetrahydrofuran,
dimethylsulfoxide, and acetone.
Zafirlukast is supplied as 10 and 20 mg tablets for oral
administration.
INACTIVE INGREDIENTS: Film-coated tablets containing croscarmellose
sodium, lactose, magnesium
stearate, microcrystalline cellulose, povidone, hypromellose, and
titanium dioxide.
CLINICAL PHARMACOLOGY
MECHANISM OF ACTION:
Zafirlukast is a selective and competitive receptor antagonist of
leukotriene D4 and E4 (LTD4 and
LTE4), components of slow-reacting substance of anaphylaxis (SRSA).
Cysteinyl leukotriene
production and receptor occupation have been correlated with the
pathophysiology of asthma, including
airway edema, smooth muscle constriction, and altered cellular
activity associated with the inflammatory
process, which contribute to the signs and symptoms of asthma.
Patients with asthma were found in one
study to be 25-100 times more sensitive to the bronchoconstricting
activity of inhaled LTD4 than
nonasthmatic subjects.
31
33
3
6
_In vitro_ studies demonstrated that zafirlukast antagonized the
contractile activity of three leukotrienes
(LTC , LTD and LTE ) in conducting airway smooth muscle from
laboratory animals and humans.
Zafirlukast prevented intradermal LTD -induced increases in cutaneous
vascular permeability and
inhibited inhaled LTD -induced influx of eosinophils into animal
lungs. Inhalational challenge studies in
sensitized sheep showed that zafirlukast suppressed the airway
responses to antigen; this includ