New Therapies for Allergic Rhinitis

“Two thirds of patients forget to take their medicines, and a third don’t feel that their medications work,” said William E. Berger, M.D., M.B.A., a clinical professor of pediatrics at the University of California, Irvine. “Patients basically want a fast onset of action and long duration, prefer not to use steroids, and want medications that are non-habit forming and that have few adverse effects.”

“We basically have patients with a chronic disease who are not completely happy with their present therapies, and that includes antihistamines, decongestants, steroids and allergy immunotherapy,” he said.

Sublingual Immunotherapy Allergy Treatment
One of the new therapeutic paradigms discussed at the annual meeting was sublingual immunotherapy (SLIT). SLIT is the most widely used non-injection allergy treatment in Europe. With SLIT there is no direct absorption of the allergen through the mucosa and has been considered a possible alternative to allergy shots, but, as research indicated, it does have some limitations.

“It is allergen specific so it only can be administered for one allergen at a time, which is one of the limitations. We’re not sure of its direct mechanism of action, but the hypothesis is that it is absorbed into the regional lymph nodes,” Dr. Berger said.

The initial dosing for a SLIT treatment is 1:1,000 dilution, and it is placed under the tongue, kept there for two minutes and then swallowed. For treatment of pollen allergy, it is given before and during the season, while it is given on a continual basis for treatment of perennial allergies.

It seems that SLIT may have some great advantages. One double-blind placebo controlled study found that SLIT was effective, and reduced drug consumption in patients with grass-pollen rhinitis, include those who had mild asthma. The main advantages of SLIT is that it is convenient to use and cost effective, but the downside is that is has to be taken every day. Compliance is limited when medication must be taken on a daily basis, said Dr. Berger.

Anti-IgE Allergy Treatment Therapy
Another new therapy is anti-IgE, which is a recombinant monoclonal antibody to IgE. It inhibits binding of IgE to high affinity IgE receptors on the surface of mast cells and basophils. The new treatment has shown to be effective for patients with asthma and/or seasonal allergic rhinitis. The anti-IgE drug that has already entered the marketplace is omalizumab (Xolair), approved for treatment of moderate-to-severe forms of allergic asthma.

Specific Immunotherapy and Anti-IgE Combination
There has also been an increased interest among medical professionals in combining specific immunotherapy (SIT) with anti-IgE monoclonal antibody treatment, as the two have complementary modes of action. In a study that evaluated the effectiveness of combined SIT and anti-IgE therapy in children and adolescents with birch and grass allergy, combination therapy reduced the symptom load by 48 percent, compared to SIT alone. During the grass season, SIT reduced symptoms by 32 percent while combination therapy reduced them by 71 percent.

Second Generation Antihistamines to Treat Allergies
Second generation antihistamines are another new allergy treatment method surfacing lately.

Azelastine
One of the newer medications is azelastine, an antihistamine that is delivered as a nasal spray. It is different from other drugs in its class in that it also exhibits anti-inflammatory activity. It stabilizes the mast cells and reduces the triggers of inflammation.

In a recent study, which compared azelastine with oral cetirizine, azelastine significantly improved the total nasal symptom score (TNSS), 29.3 percent vs. 23 percent. It also began to take effect more quickly, which is what you would expect with a nasal spray and was associated with an improved quality of life.

Olopatadine
Another new nasal antihistamine second generation nasal spray in development is Olopatadine, which is currently available as eye drops. It is non-sedating, it has anti-inflammatory activity and will have value in treating allergic inflammation, symptoms of allergic rhinitis.

In a study that evaluated the effect of olopatadine on human nasal epithelial cells, the medication significantly inhibited histamine-stimulated IL-8 in a dose dependent manner. When studied in patients with seasonal allergic rhinitis, olopatadine significantly reduced TNSS, as compared to placebo, from 90 minutes after taking the drug to 12 hours afterwards.

Ciclesonide
Ciclesonide, a new inhaled corticosteroid nasal spray, has also shown to be effective in the treatment of seasonal allergic rhinitis. The parent compound is converted locally in airways by esterases to produce the active metabolite desisobutyrl-ciclesonide (DES-CIC), said Dr. Berger, and it only works in area of respiratory mucosa.

DES-CIC is 99 percent protein bound and metabolized by the liver, causing little unwanted systemic interaction. Its effects are experienced primarily in the respiratory system. A randomized, double-blind placebo-controlled study found that TNSS changes were significant for ciclesonide, compared with placebo.

“The focus of treatments coming up in the future are safety, cost-effectiveness, improving patient compliance, as well as recognizing and treating comorbidities,” Dr. Berger said.