Published Online; January 2, 2016
Many patients are allergic to both grass and ragweed and may benefit from immunotherapy for these allergens. Sublingual immunotherapy (SLIT) tablets for the treatment of timothy grass (and related grasses) and ragweed allergic rhinitis with or without conjunctivitis (AR/C) are approved in the United States and Canada. The prescribing information for the timothy grass and ragweed SLIT-tablets recommends treatment begin at least 12 weeks before the expected onset of the respective pollen season; in North America this time period for ragweed would coincide with the grass pollen season when patients receiving grass SLIT-tablet were still undergoing treatment. To simultaneously treat both grass and ragweed AR/C, dual SLIT-tablet administration would be required.
In The Journal of Allergy and Clinical Immunology: In Practice, Maloney and colleagues published the results of an open-label, multicenter trial that characterized the safety and tolerability of dual grass and ragweed SLIT-tablet administration in adults allergic to grass and ragweed. The trial had 3 periods, each of 2 weeks duration. In the first period, patients received once-daily grass SLIT-tablet, in the second period patients received ragweed SLIT-tablet every morning and grass SLIT-tablet every evening, and in the third period patients received once-daily ragweed and grass SLIT-tablet within 5 minutes (considered simultaneous).
Single and dual administration of the SLIT-tablets were well tolerated. There were no severe swellings which could compromise the airways, systemic allergic reactions, or asthma exacerbations during any period. The most common side effects of the SLIT-tablets were throat irritation, itchy mouth, and itchy ears; nearly all (99%) of the side effects were judged to be mild or moderate in severity. When patients were receiving simultaneous SLIT-tablets, the proportion of patients experiencing local swellings or other local side effects did not increase, the proportion of patients who discontinued treatment did not increase, and side effects were not more severe compared with single SLIT-tablet treatment. In fact, the proportion of patients experiencing side effects decreased over the course of the trial. Side effects generally started within the first week of treatment, lasted from 15 to 25 minutes, and recurred for 1 to 3 days. Most patients (90%) indicated they would definitely or probably take the SLIT-tablets if asked to do so by their doctor.
This trial was the first to demonstrate a practical approach for introducing dual and simultaneous administration of SLIT-tablets. Simultaneous administration of the grass and ragweed SLIT-tablets was shown to be well tolerated. However, it is still unknown if introducing simultaneous administration of SLIT-tablets without the sequential build-up periods to ensure tolerance would increase the risk or severity of side effects.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.