General Information

Ventolin HFA is a beta2-adrenergic agonist.

Ventolin HFA is indicated for:

• Treatment or prevention of bronchospasm in adult and pediatric patients aged 4 years and older with reversible obstructive airway disease.
• Prevention of exercise-induced bronchospasm in adult and pediatric patients aged 4 years and older

Ventolin HFA is for oral inhalation only. The recommended dosing is as follows:

Treatment or prevention of bronchospasm in adult and pediatric patients aged 4 years and older:

• 2 inhalations by oral inhalation every 4 to 6 hours. For some patients, 1 inhalation every 4 hours may be sufficient.

Prevention of exercise-induced bronchospasm in adult and pediatric patients aged 4 years and older:

• 2 inhalations by oral inhalation 15 to 30 minutes before exercise.

Prime Ventolin HFA before using for the first time, when the inhaler has not been used for more than 2 weeks, or when the inhaler has been dropped. To prime Ventolin HFA, release 4 sprays into the air away from the face, shaking well before each spray.

Mechanism of Action

In vitro studies and in vivo pharmacologic studies have demonstrated that albuterol has a preferential effect on beta₂-adrenergic receptors compared to isoproterenol. Activation of beta₂-adrenergic receptors on airway smooth muscle leads to the activation of adenylcyclase, and to an increase in the intracellular concentration of cyclic-3',5'-adenosine monophosphate (cyclic AMP). This increase of cyclic AMP leads to the activation of protein kinase A, which inhibits the phosphorylation of myosin and lowers intracellular ionic calcium concentrations, resulting in relaxation. Albuterol relaxes the smooth muscles of all airways, from the trachea to the terminal bonchioles. Albuterol acts as a functional antagonist to relax the airway irrespective of the spasmogen involved, thus protecting against all bronchoconstrictor challenges.

Side Effects

Adverse events reported from clinical trials include (but are not limited to) the following:

• Throat irritation
• Upper respiratory inflammation
• Viral respiratory infections
• Cough
• Musculoskeletal pain

Overall, the adverse events were similar between Ventolin HFA and a CFC 11/12-propelled albuterol inhaler. Additionally, according to the results of a two-week pediatric trial, the pediatric adverse event profile was generally similar to that of the adults.

Clinical Trial Results

A 12-week, randomized, double-blind trial compared Ventolin HFA to CFC 11/12-propelled albuterol and an HFA-134a placebo inhaler. The trial included adolescent and adult subjects (12-76 years of age) with mild to moderate asthma. Serial forced expiratory volume in one second (FEV1) measurements showed that two inhalations of Ventolin HFA produced a significantly greater improvement in FEV1 over the pretreatment value than placebo.

A second 12-week, randomized, double-blind trial evaluated the effectiveness of switching subjects from CFC 11/12-propelled albuterol to Ventolin HFA. In an initial run-in phase, all subjects received CFC 11/12-propelled albuterol. During the double-blind treatment phase, Ventolin HFA was compared to CFC 11/12-propelled albuterol and an HFA-134a placebo inhaler in adolescent and adult subjects with mild to moderate asthma. Serial FEV1 measurements showed that two inhalations of Ventolin HFA produced significantly greater improvement in pulmonary function than placebo. The switching from CFC 11/12-propelled albuterol inhaler to Ventolin HFA did not reveal any clinically significant changes in the efficacy profile.

Additionally, a two-week, randomized, double-blind trial was conducted to compare Ventolin HFA, CFC 11/12-propelled albuterol, and an HFA-134a placebo inhaler in 135 pediatric subjects (4-11 years old) with mild to moderate asthma. Serial pulmonary function measurements showed that two inhalations of Ventolin HFA produced significantly greater improvement in pulmonary function than placebo, and that there were no significant differences between the groups treated with Ventolin HFA and CFC 11/12-propelled albuterol.

A controlled trial in adult subjects with asthma showed that two inhalations of Ventolin HFA taken approximately 30 minutes prior to exercise significantly prevented exercise-induced bronchospasm compared to an HFA-134a placebo inhaler. In addition, Ventolin HFA was shown to be clinically comparable to a CFC 11/12-propelled albuterol inhaler for this indication.