Efficacy of a House Dust Mite Sublingual Allergen Immunotherapy Tablet in Adults With Allergic Asthma

Abstract

IMPORTANCE The house dust mite (HDM) sublingual allergen immunotherapy (SLIT) tablet is a potential novel treatment option for HDM allergy-related asthma. OBJECTIVES To evaluate the efficacy and adverse events of the HDM SLIT tablet vs placebo for asthma exacerbations during an inhaled corticosteroid (ICS) reduction period. DESIGN, SETTINGS, AND PARTICIPANTS Double-blind, randomized, placebo-controlled trial conducted between August 2011 and April 2013 in 109 European trial sites. The trial included 834 adults with HDM allergy-related asthma not well controlled by ICS or combination products, and with HDM allergy-related rhinitis. Key exclusion criteria were FEV 1 less than 70% of predicted value or hospitalization due to asthma within 3 months before randomization. Efficacy was assessed during the last 6 months of the trial when ICS was reduced by 50% for 3 months and then completely withdrawn for 3 months. INTERVENTIONS 1:1:1 randomization to once-daily treatment with placebo (n = 277) or HDM SLIT tablet (dosage groups: 6 SQ-HDM [n = 275] or 12 SQ-HDM [n = 282]) in addition to ICS and the short-acting β 2-agonist salbutamol. MAIN OUTCOMES AND MEASURES Primary outcome was time to first moderate or severe asthma exacerbation during the ICS reduction period. Secondary outcomes were deterioration in asthma symptoms, change in allergen-specific immunoglobulin G4 (IgG4), change in asthma control or asthma quality-of-life questionnaires, and adverse events. RESULTS Among 834 randomized patients (mean age, 33 years [range, 17-83]; women, 48%), 693 completed the study. The 6 SQ-HDM and 12 SQ-HDM doses both significantly reduced the risk of a moderate or severe asthma exacerbation compared with placebo (hazard ratio [HR]: 0.72 [95% CI, 0.52-0.99] for the 6 SQ-HDM group, P = .045, and 0.69 [95% CI, 0.50-0.96] for the 12 SQ-HDM group, P = .03). The absolute risk differences based on the observed data (full analysis set) in the active groups vs the placebo group were 0.09 (95% CI, 0.01-0.15) for the 6 SQ-HDM group and 0.10 (95% CI, 0.02-0.16) for the 12 SQ-HDM group. There was no significant difference between the 2 active groups. Compared with placebo, there was a reduced risk of an exacerbation with deterioration in asthma symptoms (HR, 0.72 [95% CI, 0.49-1.02] for the 6 SQ-HDM group, P = .11, and 0.64 [95% CI, 0.42-0.96] for the 12 SQ-HDM group, P = .03) and a significant increase in allergen-specific IgG4. However, there was no significant difference for change in asthma control questionnaire or asthma quality-of-life questionnaire for either dose. There were no reports of severe systemic allergic reactions. The most frequent adverse events were mild to moderate oral pruritus (13% for the 6 SQ-HDM group, 20% for the 12 SQ-HDM group, and 3% for the placebo group), mouth edema, and throat irritation. CONCLUSIONS AND RELEVANCE Among adults with HDM allergy-related asthma not well controlled by ICS, the addition of HDM SLIT to maintenance medications improved time to first moderate or severe asthma exacerbation during ICS r...

EAACI Guidelines on Allergen Immunotherapy: Allergic rhinoconjunctivitis

“…Partially controlled asthma Virchow 41 One trial with SLIT tablet 41 included some subjects with partially controlled asthma without compromising safety; it is important that confirmatory evidence is acquired. …”

Effect of Adjuvanted and Standard Sublingual Immunotherapy on Respiratory Function in Pure Rhinitis Due to House Dust Mite over a 5-Year Period

“…In addition, asthma is more difficult to assess, since objective measures (PFT) are needed [19]. Nonetheless, consistent data supported the effect of AIT in this disease [16,17]. Another aspect, linking rhinitis, asthma and AIT is that rhinitis is a strong and independent risk factor for developing asthma [20] and AIT can intervene on this progression [6].…”

“…According to this, several extracts have been approved as pharmacological products by the European Medicine Agency and the Food and Drug Administration [15]. The majority of trials were conducted in rhinitis and with pollen extracts, and fewer in asthma and with mites [16,17]. The reason of this, stands in the fact that with mites there are more methodological problems, including the variable exposure and the need for long periods of observation [18].…”

Guía Mexicana del Asma: GUIMA 2017

“…Según las guías madre, su eficacia en adultos aún no se ha demostrado claramente, sin embargo, un estudio reciente, incluido en GINA 2016, con SLIT para ácaro de polvo casero, demostró un efecto benéfico modesto (ü). 51 En cuanto al costo, las guías madre señalan que con el uso prolongado de SLIT se reduce el costo total del tratamiento de rinitis con asma concomitante. (Recomendación B) 52 • SCIT: Sugerimos usar SCIT en niños y adultos con asma alérgica.…”