FCAAIA Notes: Sublingual immunotherapy (SLIT) in which melt-away tablets are placed under the tongue is an attractive idea because of its convenience. In the United States, SLIT has only been approved by the Food and Drug Administration (FDA) for grass and ragweed pollens. SLIT for those allergens is proven better than placebo, but as this study shows, it is not much better. When compared to allergy shots, injections are usually proven more effective than SLIT. Many practitioners in the US prescribe “allergy drops”, off label (that is, in a manner that is not FDA approved). Patients receiving drops are usually getting very low doses that have been proven ineffective comparable to placebo. In studies looking at SLI to multiple allergens ate once, SLIT has not been proven better than placebo.
(Source: http://www.healio.com/allergy-immunology/immunotherapy/news/online/%7B5145736a-3fc6-4bd9-9f65-853b3c6e3498%7D/evidence-does-not-support-using-slit-to-treat-sarc?utm_source=maestro&utm_medium=email&utm_campaign=allergy%20immunology%20news July 44, 2015 Adapted from JAMA Intern Med. 2015;175(8):1301-1309)
There is minimal benefit in using sublingual immunotherapy to reduce symptoms and decrease the use of symptomatic medication in patients with seasonal allergic rhinoconjunctivitis, according to study results.
“The clinical implication of our findings is that the continued widespread use of [sublingual immunotherapy (SLIT)] in Europe, as well as future use of the treatment in the U.S., is questionable,” Danilo Di Bona, MD, PhD, of the Azienda Ospedaliera Universitaria Policlinico di Palermo in Italy, and colleagues wrote. “As shown by previous meta-analyses indirectly comparing [subcutaneous immunotherapy (SCIT)] and SLIT, SCIT seems to be the most effective treatment.”
Di Bona and colleagues conducted a meta-analysis and reviewed studies included in Medline, Embase, the Cochrane Library and ClinicalTrials.gov from inception until April 2014.
The researchers included 13 randomized controlled trials of 4,659 patients with seasonal allergic rhinoconjunctivitis (SARC) to determine the efficacy and safety of grass pollen SLIT in the treatment of patients with SARC.
All studies showed a beneficial effect of SLIT on patient symptom score compared with placebo (standardized mean differences = –0.28; 95% CI, –0.37 to –0.19), however six studies did not reach statistical significance.
The researchers noted a difference in medication score between SLIT and placebo in seven studies (SMD = –0.24; 95% CI, –0.31 to –0.17).
Patients receiving SLIT (n = 2259) reported experiencing adverse events (61.3%) drastically more than patients receiving placebo (n = 2279, 20.9%).
The researchers write that although SLIT is easier to use and readily available to most people, the evidence points to not using the therapy.
“The results of this meta-analysis are sufficient to conclude that the grass pollen allergy immunotherapy tablets show an allergen-specific effect, but its magnitude is small and is complicated by adverse events,” the researchers wrote. “Therefore, the convenience and ease of administration do not seem to be sufficient reasons for the choice of SLIT.