Aims:To demonstrate the efficacy and safety of sublingual IT (SLIT) with Pru p 3 in pts with systemic reactions (SR) associated with peach ingestion, by evaluation of clinical and immunological parameters during 12 months.
Material and Methods: Eight pts (7F,1M;mean age-25.6; 19-41 years) with a history of peach allergy, confirmed by Oral Food Challenge (unless anaphylaxis symptoms and evidence of peach sensitization), undergoing SLIT Pru p 3 (ALK-Abelló) during 1 year, were evaluated. 100% of pts had SR (75% anaphylaxis) associated with peach ingestion (62.5% reported symptoms with other foods containing LTPs). All patients underwent skin prick tests (SPT; Bial-Aristegui) with aeroallergens battery, peach extract peel and pulp, other foods according to symptoms, Pru p 3 and Pru p 4 (to exclude Pru p 4 sensitization). The SLIT with Pru p 3 had an induction phase (4 days in Immunoallergology Department), followed by outpatient maintenance phase. In all pts were performed SPT and quantified specific IgE and IgG4 (sIgE and sIgG4)-UniCAP (PhadiaThermofisher) for peach and Pru p 3 before(T0), 1(T1), 6(T6) and 12 months (T12) after SLIT initiation. Basophil Activation Test(BAT) was performed by Flow2 ® CAST method (Bühlmann) with Pru p 3 extract (Alk-Abelló) with three concentrations 0.05, 0.5 and 5ug/mL at the same times.
Results: There was a significant decrease of the mean wheal diameter of SPT in T0-T12, with peel and pulp peach (p=0.0039) and Pru p 3 (p=0.0078). Quantification of sIgE to peach and Pru p 3: significant decrease of T0-T12 (p=0.0408 and p<0.001 respectively); sIgG4: significant increase of T0-T12 (p<0.0001) for the same allergens; BAT: significant decrease between the different times and in three concentrations. During the 12 months of treatment with SLIT, there were only local reactions (itching) during the induction phase in 50% of pts with spontaneous resolution.
Conclusions: In this initial evaluation, SLIT Pru p 3 seems to be a promising and safe therapeutic option for patients with severe peach allergy.