Grass Pollen Allergy Drug Grastek Is Effective, FDA Panel Says

Dec 12 (Reuters) - A panel of experts advising the U.S. Food and Drug Administration said an oral drug made by Merck & Co was effective in treating grass pollen allergy but expressed concerns about the drug's safety in children.

The advisory panel voted 9-0 that available data supported the efficacy of the immunotherapy drug, Grastek, in treating Timothy grass pollen allergy in patients 5 years or older.

The committee also voted unanimously in favor of the drug's safety, on the condition that patients taking the drug have easy access to epinephrine - a medicine used to treat serious allergic reaction such as ones that can result from the use of immunotherapies.

Panelists recommended post-approval studies of the drug to test its safety in children aged 5 to 11 years, citing side effects such as lip swelling, throat irritation and tightness and oral blistering.

Grastek is an immunotherapy drug which contains extracts of Timothy grass allergen. Immunotherapies work by boosting the body's immune system and making it less sensitive to allergens.

The tablet, meant to be placed under the tongue, helps the body to adjust to the allergen. It is sold as Grazax in Europe by Merck's partner ALK Abello.

The FDA usually takes the recommendations into account while making a decision on approving a drug, but it is not obligated to follow them.

On Wednesday, the committee backed another allergy immunotherapy made by France's Stallergenes SA.

Stallergenes' Oralair is also to be placed under the tongue and comprises extracts from five grass pollens - Kentucky bluegrass, Orchard, Perennial rye, Sweet vernal and Timothy.

Allergen-specific immunotherapies are ideal for patients whose symptoms are not adequately controlled by avoiding the allergens or by medicines, those suffering from allergy drug-related side effects, or who wish to reduce the long-term use of drugs.