Sublingual Desensitization in Patients with Wasp Venom Allergy: Preliminary Results

Abstract

The aim ofthis paper is to assess in an open prospective pilot case-control study the tolerability, safety and efficacy of an ultra-rush sublingual immunotherapy (SLIT) protocol with Vespula venom in wasp allergic patients compared to subcutaneous immunotherapy (SCIT). Forty-one wasp allergic patients were treated with sublingual (SLIT group) or subcutaneous (SCIT group) ultrarush immunotherapy with Vespula venom extract. All patients underwent skin tests and serum specific IgE and IgG 4 detection before enrolment and after 6, 12 and 24 months of immunotherapy. The SLIT group consisted of 21 (6 females and 15 males) patients who received increasing doses of Vespula venom (Aquagen, ALK-AbeIl6) until the final dose of 30 drops of extract in 3 hours, containing 100,000 SQ-U/ml. The maintenance dose was of 10 drops of pure venom extract 3 times a week, for a total dose of 100,000 SQ-U weekly (corresponding to 100 JIg of venom extract). The SCIT group consisted of 20 patients (16 males and 4 females) who were treated with subcutaneous ultrarush immunotherapy with Vespula venom extract (Pharmalgen, Alk-AbeIl6). Patients received 101.1 j..lg of Vespula venom in 3 hours and were treated with 100 ug of wasp venom monthly. During the ultrarush sublingual treatment 2 patients (9.5%) experienced mild side-effects. Specific IgE and specific IgG to wasp venom did not show any significant modification. Four patients were field-stung by a wasp during the treatment (for a total of 6 stings). Two patients (3 stings), with a previous clinical history of a grade III and IV reaction, did not experience any reaction. One patient, with a previous grade II reaction, showed a large local reaction. The fourth patient, with a previous grade III reaction, was re-stung twice (after 12 and 24 months) with two systemic reactions (SR) (mild throat constriction). During the ultrarush SCIT phase, 3 (15%) patients experienced side-effects: 2 of them showed a large local reaction and 1 had headache and stomach ache. Specific IgE showed a significant (P=O.OOI) increase after 6 months of treatment and then returned to baseline levels while specific IgG showed a significant (P=O.OOI) increase after 6, 12 and 24 months in comparison with baseline. Nine patients were field-stung during the treatment: 8 of them experienced large local reactions; one patient (11%) experienced an SR (dizziness). Our results, even if in a small number of patients, suggest that in patients with Hymenoptera sting allergy SLIT could be efficacious with a good tolerability profile when compared to SCIT. Larger studies are needed to assess efficacy, safety and tolerability profile of wasp venom SLIT.

Current developments for improving efficacy of allergy vaccines

“…Venom immunotherapy (VIT), delivered by the subcutaneous route, has been used successfully for many years and is the current recommended gold standard treatment for subjects with severe insect sting allergy associated with anaphylaxis [27,52]. Two small studies exploring the sublingual route [30,31] showed some benefit but larger trials are needed. The severity of previous reactions informs the choice of VIT as a correlation is established between the frequency of systemic reactions to subsequent stings and the severity of previous reactions, with 40-60% risk of further severe reactions in subjects who have experienced prior anaphylaxis [53].…”

“…Randomized controlled trials (RCT) of SCIT and SLIT showed clinical efficacy, further confirmed by meta-analyses [13,[22][23][24][25] and systematic reviews [26][27][28][29]. SCIT is effective in preventing systemic and large local allergic reactions to insect stings [27] with some data indicating similar success with the sublingual route [30,31]. Recent studies and subsequent meta-analysis have shown that AIT may be effective for atopic dermatitis (AD) [32] and food allergy [23].…”

Sublingual immunotherapy with venom for patients with Hymenoptera venom allergy

“…In reply to Patriarca et al, 1 we acknowledge the fact that we did not refer to their publication 2 in our recent comment on the study by Severino et al 3 However, we omitted the study by Patriarca et al 2 deliberately, because this study also does not present data that show effectiveness of sublingual venom immunotherapy (SL-VIT).…”

Stinging insect allergy: current perspectives on venom immunotherapy

“… 90 An observational study of wasp SLIT in 2 1 patients showed good tolerability and suggested possible efficacy. 91 An observational study of bee venom SLIT suggested reduced LLR in the majority of patients treated. 92 A single randomized controlled trial of SLIT VIT was identified in the Cochrane review: 19 there was no evidence that SLIT was less effective than SCIT for reducing risk of SR or LLR in that review, although this preliminary conclusion was based on a small number of studies and participants.…”