Mayo Clinic Receives Patent for New Treatment of Chronic Sinus Infection

Mayo Clinic yesterday received broad patent coverage for a new treatment of chronic rhinosinusitis (CRS), commonly called "sinus infection," a disease that annually affects 32 million adults in the United States and currently has no Food and Drug Administration-approved treatment. Studies at Mayo Clinic have found the cause of CRS -- a reaction to certain fungi -- and demonstrated that the delivery of antifungal drugs directly into the nose and sinuses is safe and significantly reduces patients? symptoms. Improvements in asthma symptoms were noted in the same patient group. Past medical treatments for chronic sinus infections have been unsuccessful or produced severe side effects.

From Mayo Clinic:
Mayo Clinic Receives Patent for New Treatment of Chronic Sinus Infection

More than 32 million adults affected annually by disease

ROCHESTER, Minn. -- Mayo Clinic yesterday received broad patent coverage for a new treatment of chronic rhinosinusitis (CRS), commonly called "sinus infection," a disease that annually affects 32 million adults in the United States and currently has no Food and Drug Administration-approved treatment.

Studies at Mayo Clinic have found the cause of CRS -- a reaction to certain fungi -- and demonstrated that the delivery of antifungal drugs directly into the nose and sinuses is safe and significantly reduces patients? symptoms. Improvements in asthma symptoms were noted in the same patient group. Past medical treatments for chronic sinus infections have been unsuccessful or produced severe side effects.

"We?ve seen significant improvement in the quality of life for the large majority of patients with chronic sinus infection who were treated with antifungal drugs," says David Sherris, M.D., a Mayo Clinic ear, nose and throat specialist and one of the project researchers. "Many of them had been miserable for years and were severely hampered at work and in social situations by their illness. Many are pain-free and able to breathe effectively through their noses for the first time in years."

CRS is one of the most common chronic diseases in the United States. CRS produces nose and sinus problems characterized by nasal airway obstruction, loss of the sense of smell, postnasal drip, nasal congestion, nasal discharge, and head and face pain lasting three months or longer. It notably decreases the quality of patients? lives, impairing physical and social functioning, vitality and general health.

CRS has a significant impact on health care in the United States.

- The prevalence of CRS has increased by more than 50 percent in the past 10 years.

- CRS results in 18.3 million physician visits per year.

- Overall health-care expenditures attributable to CRS in the United States were estimated to be over $5.8 billion in 1996.

- In 2001, 27.9 million prescriptions were issued to treat CRS in the United States.

- Approximately $2 billion is spent annually to treat nasal and sinus disorders.

The road to the patents began with research at Mayo Clinic into the cause of the disease. Jens Ponikau, M.D., Eugene Kern, M.D., and Dr. Sherris, who are Mayo Clinic ear, nose and throat specialists, and Hirohito Kita, M.D., a Mayo Clinic allergic diseases researcher, led a group of investigators who demonstrated the presence of fungi in everyone?s nasal mucus. However, patients diagnosed with CRS have an immunologic response to the fungi causing activated white blood cells (eosinophils) to enter their mucus. The activated eosinophils release a major basic protein -- a toxic protein -- into the mucus, which attacks and kills the fungi but damages the nose and sinus membranes. The major basic protein also injures the epithelium, which allows bacteria to infect the tissues.

Mayo Clinic?s pioneering medical treatment for CRS is designed to stop antigen release by administering antifungal drugs. Without fungal antigens, the immune reaction does not occur, eosinophils do not enter the nasal mucus, major basic protein is not released and damage to the nasal and sinus linings is eliminated.

Clinical studies first conducted by Mayo Clinic found that this treatment provided greater improvement of symptoms than other treatments that have been used. Past treatments used by physicians include antibiotics and systemic or inhaled steroids, as well as endoscopic sinus surgery.

Mayo Clinic conducted a prospective open-label trial using amphotericin B, an antifungal drug, in 51 randomly selected CRS patients. Treatment with amphotericin B resulted in an improvement of CRS symptoms in 38 of 51, or 75 percent, of the patients. Endoscopically, 18 of 51, or 35 percent, of the patients became disease free; an additional 20 patients, or 39 percent, improved mildly; no effect was seen in 13, or 25 percent, of the patients. Researchers in Switzerland conducted a similar open trial and confirmed Mayo Clinic?s results.

The National Institutes of Health has committed itself to further investigation of the fungal link to chronic sinus infection and the role of antifungal medications in treatment of the disease, as cited on http://www.niaid.nih.gov/director/congress/2002/cj/sigitems.htm.

So far, Mayo Clinic has received broad patent coverage that protects the delivery of antifungal drugs to mucus in the nose and sinuses. The patents are:

- 6,207,703 - Antifungal treatment of asthma - 6,291,500 - Antifungal treatment of colitis - 6,416,955 - Eosinophil degranulating conditions - 6,555,566 - Antifungal treatment of CRS

The issuance of the CRS treatment patent completes Mayo Clinic?s portfolio on antifungal treatment of inflammatory conditions such as CRS, asthma and colitis and may offer pharmaceutical companies an incentive to invest in this technology to make it widely available to patients. The U.S. Patent and Trademark Office also has allowed claims for treatment of asthma and CRS combined; the patent is expected to be forthcoming.

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Lee Aase
Lisa Copeland
John Murphy
507-284-5005 (days)
507-284-2511(evenings)
email:newsbureau@mayo.edu

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May 12, 2003