After a long absence, Primatene Mist, an over-the-counter asthma inhaler removed from the market in 2011, is being reintroduced in a metered-dose inhaler with a new, environmentally friendly propellant.
But the inhaler’s comeback may prove as controversial as its removal. Respiratory medicine associations have taken issue with the Food and Drug Administration’s decision, warning patients that asthma is not a “do-it-yourself” disease that can be managed with over-the-counter medications.
The American College of Allergy, Asthma, and Immunology, American College of Chest Physicians, American Lung Association, American Thoracic Society, and the American Association of Asthma Educators have each individually protested the decision, and together sent a joint resolution to FDA decrying it. At the core of their protest are the facts that epinephrine is a symptomatic, not therapeutic, asthma treatment and that racemic epinephrine is not a not a recommended asthma treatment under the National Institutes of Health’s “Guidelines for the Diagnosis and Management of Asthma.”
CHEST has published the following statement: “The American College of Chest Physicians (CHEST) is disappointed with the FDA’s decision to approve over-the counter epinephrine (Primatene® Mist HFA) for the treatment of asthma. CHEST is a nonprofit organization dedicated to advancing best patient outcomes. Our membership of more than 19,000 members from around the world provides patient care in pulmonary, critical care, and sleep medicine.
Asthma is a serious and chronic condition with associated high health-care burden. Care for ALL patients with asthma should be under the guidance of a health-care provider. The majority of asthma patients requires treatment with a controller medication, which is only available by prescription. Frequent rescue inhaler use has been associated with increased morbidity and mortality. Over the counter availability of a reliever medication like Primatene Mist can endanger a patient’s wellbeing by providing temporary relief in symptoms, resulting in delay in seeking medical care.”
The inhaler was pulled from sales as part of an international pact to reduce ozone-depleting substances. The 1989 Montreal Protocol of Substances that Deplete the Ozone Layer and the Clean Air Act of 1990 targeted chlorofluorocarbons among those substances, and epinephrine inhalers that contained CFCs were phased out.
The new Primatene Mist HFA (Amphastar Pharmaceuticals) contains hydrofluoroalkane (HFA) propellants, which are permitted under current international and U.S. law. This puts Primatene in the same category with other inhalers, including albuterol and levalbuterol, which also use HFAs as propellants. Each dose delivers 125 mcg of epinephrine.
The inhaler itself has also been redesigned, according to Theresa Michele, MD, director of the FDA’s Division of Nonprescription Drug Products in the Center for Drug Evaluation and Research. The active ingredient is still epinephrine, albeit a smaller dose than found in the original 200-mcg mist. However, the inhaler needs to be activated before first use and cleaned every day after use to prevent a medication buildup. Like other metered-dose inhalers, it requires a priming spray before the inhalation dose, Dr. Michele noted in her online column.
“The inhaler also needs to be shaken and then sprayed once into the air before each use. It may seem strange to shake and spray the inhaler into the air each time before using it. But these two steps are critical to ensure that the medicine is properly mixed before each dose,” Dr. Michele wrote.
A public statement by FDA Commissioner Scott Gottlieb, MD, and Janet Woodcock, MD, director of the Center for Drug Evaluation and Research, asserted that the inhaler fills a clinical gap for patients with mild to moderate intermittent asthma.
“The scientific information we reviewed to approve the new version of OTC Primatene Mist shows there is a narrow population of those diagnosed with asthma that may benefit from having access to this type of OTC asthma inhaler. But the product has certain cautions. Making sure that patients can understand and apply the instructions for use was a critical consideration for the FDA. The new product is only appropriate for those with a diagnosis of mild, intermittent asthma. Patients with more severe asthma should not rely on it. Instead, they should be working with their health care provider to ensure an appropriate treatment plan for their condition.”
Before this approval, Amphastar had unsuccessfully brought the reformulated Primatene before FDA several times. The move to finally reinstate it comes after a long, and sometimes contentious, debate among patients and FDA’s Nonprescription Drugs and Pulmonary-Allergy Drugs advisory committee. A quick Internet or Facebook search brings up dozens of stories from patients who say they effectively managed their mild to moderate asthma for years with Primatene. Typically, the stories describe changing to prescription asthma medications that, for some, run into the hundreds of dollars per month. Supporters often negatively compare decades of using the inexpensive Primatene with no ill effects to their recent experiences using prescription corticosteroid inhalers.
It was 4 years ago when Amphastar first appeared before the advisory committee with the reformulated inhaler and positive safety and efficacy data. Although agreeing with the efficacy data, the advisory committee voted against approval, because some felt that asthma should always be managed by a physician; an OTC bronchodilator encouraged self-medicating and discouraged patients from seeking medical care, they said.
“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,” FDA documents noted. “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.”
Two years later, the company received another blow to Primatene program. FDA’s Complete Response Letter required Amphastar to make additional changes to the packaging and run a consumer product safety study, intended to show that people could learn to use the metered-dose inhaler correctly.
In Amphastar’s 2018 first-quarter report, however, company CEO Jack Zhang, PhD, finally shared some good news. “We are pleased to announce that we have resubmitted our NDA for Primatene Mist after receiving good results from our recent human factors study. While we don’t have a Prescription Free User Drug Act [PDUFA] date yet, we plan to begin producing inventory in preparation for a launch.”
That day arrived on Nov. 8, when the PDUFA was granted. In their public letter, Dr. Gottlieb and Dr. Woodcock acknowledged the long and difficult approval path and offered reassurance that Primatene is safe and effective.
“For the right patient, our analysis of the data, including new information that was developed since this product was previously on the market, shows that there are no serious safety concerns when Primatene Mist is used as directed. The product is appropriate for mild symptoms of intermittent asthma, however, even patients with mild asthma can have severe exacerbations – so it’s still important to consult a health care provider about appropriate care and have their condition reassessed. And, of course, all patients who experience severe exacerbations should go to the emergency room right away.”
Primatene Mist HFA is intended for the temporary relief of mild symptoms of intermittent asthma (wheezing, tightness of chest, shortness of breath) in patients aged 12 years and older. It should not be considered a replacement for prescription asthma medications. It should be available in stores early next year.