The majority of a Food and Drug Administration advisory panel rejected approval of a newly formulated replacement for Primatene Mist as an over-the-counter treatment for asthma, at a recent meeting.
The FDA’s Nonprescription Drugs and Pulmonary-Allergy Drugs advisory committees voted 18 to 6 that the epinephrine metered-dose inhaler for the temporary relief of mild symptoms of intermittent asthma, as an OTC product, did not have a favorable risk-benefit profile.
On Feb. 25, the panel voted 14 to 10 that the efficacy data provided "substantial evidence" that treatment with the device was effective for the proposed indication, "the temporary relief of mild symptoms of intermittent asthma, including wheezing, tightness of chest, and shortness of breath," in adults and children aged 12 years and older. But in a 17 to 7 vote, the majority of the panel voted that safety had not been adequately demonstrated.
Armstrong Pharmaceuticals bought the rights to the Primatene Mist trademark from Wyeth and developed the new chlorofluorocarbon (CFC)-free version, which uses hydrofluoroalkane (HFA) as a propellant and has a proposed tradename of Primatene HFA. Primatene Mist, approved for treating asthma symptoms in 1967, was phased out as part of the Montreal Protocol on Substances that Deplete the Ozone Layer and taken off the market in 2011, because it used CFCs as a propellant. Primatene Mist delivered 200 mcg of epinephrine per actuation; Primatene HFA delivers 125 mcg per actuation. Epinephrine is a short-acting beta2-agonist bronchodilator.
Although the 12-week phase III study showed that treatment with the product showed statistically significant differences in the area under the curve (AUC) change in percent forced expiratory volume in 1 second (%FEV1) at week 12, over placebo, the primary endpoint, the FDA briefing documents said that concerns with the OTC availability of the product include the potential for overuse and off-label use, as well as the reliability of the device.
The agency sought the advisory panel’s input on the risk-benefit issue, noting that the public had raised concerns "both for and against the need for an OTC asthma treatment option," according to the FDA documents. "On the one hand, it has been stated that a quick-relief medication available OTC is needed for use in low-income, elderly, and uninsured individuals who might otherwise not have access to treatment or be able to see a health care practitioner. In contrast, there is also a concern that because asthma is a potentially life-threatening condition that should be diagnosed and treated by a health care professional, availability of an OTC bronchodilator product may discourage consumers from seeking appropriate care, resulting in worse asthma outcomes."
The FDA usually follows the recommendations of its advisory panels. There are no metered-dose inhaler bronchodilators currently available as OTC products in the United States.