Clinical efficacy and safety of sublingual whole bacterial extract as an adjuvant to allergen-specific immunotherapy in allergic rhinitis

Abstract

Background: In allergic rhinitis (AR), allergen-specific immunotherapy (SIT) is the only disease-modifying treatment. It may include adjuvants to improve tolerance and safety.

Objective: To evaluate the efficacy, safety, quality of life, medication reduction, and number of infections with sublingual (SL) administration of whole bacterial extract (WBE) as an adjuvant to SIT in AR.

Methods: An experimental, randomized, double-blind, controlled study was conducted with 40 patients aged 5 to 60 years with moderate or severe AR due to SSTN. Patients were randomly assigned to an experimental group (SLIT with a standardized extract for Dermatophagoides pteronyssinus and/ or Dermatophagoides farinae and SBE) or a control group (SLIT with a standardized extract for Dermatophagoides pteronyssinus and/or Dermatophagoides farinae). TNSS, RQLQ, medication, infections, and adverse effects were assessed at 30, 60, and 90 days.

Results: Both groups showed clinical improvement; however, there was only a significant change in the TNSS in the experimental group (p=0.049). Respiratory infections decreased in both groups, and the reduction in medication use was more evident in the experimental group from the first month. Two patients in the control group reported mild local adverse effects.

Conclusion: Compared with other studies that used different adjuvants and routes of administration, similarities were observed in the reduction of symptoms and medication use. No previous studies were found comparing the reduction of infections or improvement in quality of life with SIT and bacterial lysates. Bacterial suspension as an adjuvant to SLIT with standardized extracts in AR for mites is effective and safe.

Keywords: Efficacy; Bacterial extract; Sublingual immunotherapy; Allergic rhinitis; Safety.