TRENTON, N.J. (AP) -- Drugmaker Merck & Co. said Wednesday that federal regulators are reviewing its application to sell a new type of treatment for grass pollen allergy that gradually reduces allergy symptoms over time, rather than just temporarily relieving the sneezing and itching.
The treatment, a tablet that quickly dissolves under the tongue, could become the first alternative available in the U.S. to getting a long series of uncomfortable allergy shots. Both methods work by gradually desensitizing the patient's immune system to the substance triggering the allergic reaction.
Merck's immunotherapy, still unnamed, would be taken daily throughout allergy season for three years.
The company said six late-stage studies of the tablet in nearly 3,500 adults and children — conducted during peak spring and summer pollen season — found that it was safe and effective at reducing grass allergy symptoms. Those include runny nose, congestion, sneezing and itchy, watery eyes.
The most common side effects reported were itchiness of the mouth and ear and throat irritation.
"This product will be used by tens of millions of people," predicted WBB Securities analyst Steve Brozak. "Patients will readily adopt it."
Brozak said he expects Merck will advertise the therapy heavily to consumers in hopes of attracting both patients considering allergy shots and the many more who regularly take prescription or over-the-counter medicines to relieve symptoms.
Dr. Linda Cox, president of the American Academy of Allergy, Asthma & Immunology, called immunotherapy tablets a "major advance" in patient treatment because they are being developed for multiple common allergy types.
"People who are now just toughing it out (with symptomatic treatment) will now have a better option," she said, and with the treatment "might need an occasional antihistamine" during grass pollen season, "versus multiple medications and possibly an asthma flare-up."
Based on study data for Merck's experimental treatment and one a French company has been developing, patients should just need to take an occasional antihistamine for at least a couple of years after treatment ends, she said.
Immunotherapy is the only treatment approach that targets the underlying cause of an allergy to substances such as pollen, dust mites, stinging insects and pet dander.
Cox noted about 95 percent of allergy patients just take medicines for symptoms, while 2 percent to 5 percent — generally those with multiple serious allergies — have been getting allergy shots.
"There's about 8 million injections given a year," she noted.
The shots, injected just under the skin, typically have been given once or twice a week in increasing doses for 3 to 6 months, followed by a maintenance period of 3 to 5 years with monthly booster shots. More recently, allergy specialists have been using the "cluster" technique, reducing sensitivity faster by giving 2 to 3 dose increases on each of two weekly visits over a month. That's also followed by a maintenance period.
Merck, based in Whitehouse Station, N.J., said it expects the Food and Drug Administration to decide whether to approve the treatment in the first quarter of next year.
It has been approved for several years in Europe, where it is sold under the brand name Grazax by Merck partner ALK-Abello.
Merck wouldn't say Wednesday what it expects to charge for the tablets here. Box noted that when they were launched in Europe in 2006, the price was 2.95 euros per pill, or roughly $3.75 at today's exchange rates. Patients with insurance getting allergy shots typically have a small copay, often $5 or less, because a nurse gives the injections, but all those appointments are time-consuming.
Cox served as the primary investigator in a clinical trial of another grass pollen immunotherapy tablet developed by France's Stallergenes S.A. The FDA accepted that company's application for approval of its experimental treatment on Feb. 18.
Merck recently applied to the FDA for approval to sell an immunotherapy tablet for ragweed pollen. The FDA has not yet determined whether that application is complete enough to accept for review.
Merck, a leader in asthma and allergy treatments with medicines including Singulair, Clarinex and Nasonex, also is doing patient tests of an immunotherapy tablet for house dust mites.
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