New Immunotherapy Tablet for Grass Allergy: Phoenix Residents Should Read the Fine Print

Last month, the Allergenic Products Advisory Committee  of the Food and Drug Administration (FDA) voted to approve two sublingual allergy immunotherapy  products.  The FDA will need to give final approval, but this typically follows the advice of its advisory committees.   Both products contain a mixture of pollen from several different grasses commonly found in Europe and the United States.

These would be the first FDA-approved forms of sublingual allergy immunotherapy available in the US.  This is good news because the current use of sublingual immunotherapy is unregulated and therefore of undetermined safety and efficacy. And (often of more importance to patients) sublingual immunotherapy is not covered by insurance.

The bad news is that Arizona is not like Europe (at least from an allergy point of view), nor is it like most of the United States either.  It’s hot and dry. Very hot and dry!  Too hot and too dry for most grasses to survive without constant watering making them too expensive to grow.  The exception to this is Bermuda grass.  Bermuda grass is a heat and drought tolerant grass that has become THE landscaping grass in Arizona.  If it is green and growing on the ground in Arizona during the summer it is Bermuda grass.

Bermuda grass is also very allergenic.  It’s affect on allergy sufferers is so great that a Phoenix ordinance requires that grass lawns and fields be cut short to limit pollen production.   The majority (if not all) of the school playgrounds and sports fields in Phoenix are planted in Bermuda grass which means that kids are particularly vulnerable to grass pollen allergy.   It causes nasal and eye allergy symptoms late spring through fall and is often the trigger for severe allergic asthma attacks.

As important as Bermuda grass is for Arizona allergies, the new grass immunotherapy tablets do not contain Bermuda grass.  Many grasses are grouped into families that produce what are called “cross reacting” allergens.  In other words, even thought the grasses have different names and appearance, our immune system reacts to the pollen as though they were from the same, or very similar, plant.   Bermuda grass however does not have any important close cousins, so none of the pollen in the new grass tablets will help to alleviate symptoms causes by Bermuda grass.

And so. Good news:  A grass pollen tablet for allergies may be approved by the FDA.  The bad news:  It will not benefit you if you live in Arizona.