The safety of a novel sublingual rush induction phase for latex desensitization

In latex allergic individuals the avoidance of all exposure to natural rubber latex products is recommended. Sublingual immunotherapy against latex has recently been proposed. The aim of the study is to evaluate the tolerability of sublingual immunotherapy with latex extract, by a double-blind, placebo-controlled study, according to a three-day build-up phase rush protocol in a population of patients with latex-induced contact urticaria without a professional exposure to latex.

Twenty-one patients with latex-induced urticaria were randomized to receive sublingual immunotherapy (SLIT) with latex extract or placebo. Rush (3-day) induction protocol of latex sublingual immunotherapy was performed with increasing doses of ALK-Abelló latex extract at three concentrations of latex proteins (5, 50 and 500 microgmL(-1)). Any side-effects that might be related to immunotherapy, the corresponding dose and treatment were registered.

Among the 21 patients, 12 were treated with latex sublingual immunotherapy (9 women and 3 men) and 9 with placebo (8 women and one man). All patients ended the rush protocol. Four patients (19.0%) [one in the SLIT group (8.3%) and three in the placebo group (33.3%)] developed adverse reactions. One SLIT patient reported mouth itching and burning of the tongue. In the placebo group, one patient presented gastrointestinal complaints while two patients reported unspecific symptoms. All these side-effects regressed spontaneously. No statistically significant differences were found between the proportions of adverse events in the two examined groups.

This study supports the safety of SLIT against latex conducted in adult patients with latex-induced contact urticaria according to a 3-day build-up phase rush protocol. The proposed 3-day induction phase for latex sublingual immunotherapy should be conducted under medical supervision, although in patients with only latex-induced contact urticaria the registered adverse reactions were so slight that it could be argued that patients could start safely our tested rush protocol at home.