RESUMO
BACKGROUND: Hymenoptera venom immunotherapy (VIT) is a clinically effective treatment. However, little is known about its long-term clinical efficacy and biological effects. Several mechanisms have been proposed to account for VIT efficacy, including reduction of specific IgE and induction of allergen-specific IgG4, but the overall picture remains elusive. We investigated Vespula VIT clinical efficacy up to 8 years after discontinuation and the kinetics of Vespula-specific IgE and IgG4. Out of 686 consecutive patients we retrospectively selected and analysed a series of 23 patients with Vespula allergy that underwent a 5-year IT course, followed by a prolonged follow-up. METHODS: Clinical efficacy of VIT was assessed as number and severity of reactions to Vespula re-stinging events. The presence of Vespula-specific IgE and IgG4 was also monitored over time. RESULTS: During the VIT treatment, patients were protected, reporting no reactions or mild reactions in occasion of re-stinging events. This protection was entirely maintained during the follow-up, up to 8 years. Skin reactivity (reflecting mast cell-bound Vespula-specific IgE) and circulating Vespula-specific IgE levels declined substantially during VIT. Notably, this reduction was maintained over time during the follow-up. Moreover, all the patients were analysed for IgG4. A robust induction of Vespula-specific IgG4 was observed during the VIT course, with a substantial decline during the follow-up. CONCLUSIONS: We conclude that Vespula VIT is a clinically effective treatment, which induces long-term protection after discontinuation. The reduction of specific IgE, assessed by skin tests and RAST, closely matches the VIT- induced protection, while the IgG4 induction seems not to be associated with VIT clinical efficacy in the long term.
RESUMO
BACKGROUND: Randomized Controlled Trials showed that omalizumab exhibited a good safety and tolerability profile in patients with moderate-to-severe asthma. However, safety data of long-term treatment with omalizumab are scarce. Our aim was to assess the safety of omalizumab in patients under long-term treatment in a real-life setting. METHODS: Difficult-to-control asthmatic patients treated with omalizumab up to 9 years were retrospectively evaluated. Mild to severe adverse events any and reasons for discontinuation were recorded. RESULTS: Ninety-one patients (26.4% males, mean age 49.9 ± 14.9 years) were included: mean treatment length, 3.8 ± 2.6 years; mean individual monthly dose, 514.5 ± 345.7 mg (range, 150-1200 mg). A total of 10,472 single injections were given cumulatively to the 91 patients (115 single injections per patients, on average, over a treatment period up to 9 years). Fifty-nine patients (64.8%) were treated for a period of time from 3 to 9 years, 14 of whom from 6 to 9 years. A high proportion of patients who discontinued treatment dropped out within the first year (18, 39.1%), mainly for reasons unrelated to treatment. Six patients (6.6%) discontinued omalizumab for treatment-related adverse events: arthralgia/myalgia (3 patients); urticaria, angioedema (1 patients); metrorrhagia (1 patient); relapsing herpes labialis (1 patient). Four other patients complained of mild adverse events (rhinitis/conjunctivitis, injection site reaction, fatigue, thrombosis) but continued the treatment. Anaphylaxis was not reported. CONCLUSIONS: Long-term treatment with omalizumab appears remarkably safe and well tolerated in real-life setting. Prolonged omalizumab treatment for many consecutive years did not increase the risk of side effects, particularly anaphylaxis.
