There are two forms of sublingual immunotherapy (SLIT)
- FDA-approved sublingual allergy tablets
- Out of the approximately 45 different allergens that are used for traditional immunotherapy with allergy shots, there are FDA- approved sublingual allergy tablets for three different allergens- dust mite, ragweed, and grass. These three commercially available products underwent the same FDA approval process that all traditional medications must go through and are prescribed and filled through traditional pharmacies.
- Sublingual allergy drops
- Many allergy practices (like ours) offer sublingual allergy drops. The vaccines for the allergy drops are made in the lab of the individual allergy practices. We use the same FDA-approved allergy extracts that we use for the allergy shot vaccines. In this case, the route of administration of the allergy drops (under the tongue) is what is not FDA approved. The allergen extracts we use go through the standard FDA manufacturing approval process. Unlike the FDA-approved allergen tablets, we can use all of the environmental allergens needed to treat the full spectrum of environmental allergies.
Are the FDA- approved allergy tablets widely used?
No. Sales for the allergy tablets have been a big disappointment for the pharmaceutical industry and have not gained traction in clinical practice. The primary reason for this likely relates to the lack of real world utility. Only three allergens have been FDA approved. The vast majority of people have allergies to a wide range of environmental allergens and these FDA approved tablets are simply not practical for most people.
Will there be more environmental allergens approved by the FDA?
This is very doubtful. The clinical studies required to attain FDA approval are time consuming and very expensive. Given the disappointment of the commercially available FDA-approved allergen tablets, it is highly unlikely that pharmaceutical companies will be willing to undertake any further financial commitment in this space.
Posted on Tue, March 10, 2020
by Dr. Brian Rotskoff