Table 1 Summary of the described 300 IR SLIT studies
Study | Design and objectives | Allergen preparation | Population | Treatment and enrolled patients | Endpoints | Main results |
|---|---|---|---|---|---|---|
SLIT tablets | ||||||
5-grass pollen tablet | ||||||
Didier et al. [16] | Multinational, randomised, DBPC study Efficacy and safety | 5-grass pollen extract (orchard, meadow, perennial rye, sweet vernal, and timothy grasses) | Age 18–45 years Men and women with moderate-to-severe grass pollen-related ARC for ≥2 years, with or without mild asthma | 100 IR (n = 157) 300 IR (n = 155) 500 IR (n = 160) Placebo (n = 156) | RTSSa Individual symptom scores (sneezing, runny nose, itchy nose, nasal congestion, watery eyes, itchy eyes) Symptom-free days during the pollen season Rescue medication use during the pollen season Quality of life (RQLQ) Patients’ global evaluation of treatment Safety | Both the 300 IR and 500 IR doses significantly reduced mean RTSS (3.58 ± 3.0, p = 0.0001; and 3.74 ± 3.1, p = 0.0006, respectively) vs placebo (4.93 ± 3.2) The score for the 100 IR group was not significantly different from placebo Analysis of all secondary efficacy variables (sneezing, runny nose, itchy nose, nasal congestion, watery eyes, itchy eyes, rescue medication usage, and quality of life) confirmed the efficacy of the 300 IR and 500 IR doses No serious side effects were reported |
Larsen et al. [31] | Single-centre, randomised, DBPC study Safety | 5-grass pollen allergens (orchard, meadow, perennial rye, sweet vernal, and timothy grasses) | Age 18–50 years Men and women with grass pollen-induced AR, with or without mild asthma | Groups 1 and 2: incremental 100 IR, 200 IR, 300 IR, 400 IR and 500 IR SLIT (n = 6) or placebo (n = 4) (Group 1 daily and Group 2 every second day) Groups 3 and 4: repeated constant 300 IR and 500 IR SLIT, respectively (Group 3: n = 6, Group 4: n = 5) or placebo (Group 3: n = 1, Group 4: n = 2) | AEs, focusing on date of onset, occurrence, duration, intensity, action taken, outcome, and relationship to study drug Definition and grading of allergic side effects according to WHO | 300 IR SLIT (Group 3) administered in a constant dose and incremental doses up to 500 IR (Groups 1 and 2) was generally well tolerated The majority of AEs were mild to moderate Most common AEs: oral pruritus, throat irritation, swollen tongue Severe local AEs (swelling of throat) were observed only for Group 4 No serious systemic AEs were reported |
Malling et al. [32] | Multinational, randomised, DBPC study Efficacy and safety | 5-grass pollen extract (orchard, meadow, perennial rye, sweet vernal, and timothy grasses) | Age 18–45 years Men and women with moderate-to-severe grass pollen-induced ARC for at least 2 years, with or without mild asthma | For Group 1 (high specific IgE), Group 2 (high symptom scores), Group 3 (high skin sensitivity) and Group 4 (any of Groups 1, 2 or 3), respectively: ITT population (n = 569) 100 IR SLIT (n = 55, 61, 34, 105) 300 IR SLIT (n = 59, 47, 32, 100) 500 IR SLIT (n = 57, 60, 39, 103) Placebo (n = 80, 56, 37, 105) Safety population (n = 628) 100 IR SLIT (n = 62, 67, 37, 117) 300 IR SLIT (n = 69, 52, 36, 112) 500 IR SLIT (n = 66, 66, 44, 117) Placebo (n = 82, 59, 40, 112) | ARTSSa Individual symptom scores RTSS at the peak of the pollen season Symptom-free days during the pollen season Rescue medication use during the pollen season Quality of life (RQLQ) Patients’ global evaluation of treatment Safety | Across the 4 groups, ARTSS (±SD) for 300 IR was 3.91 ± 3.16 (Group 1), 3.83 ± 3.14 (Group 2), 2.55 ± 2.13 (Group 3) and 3.61 ± 2.97 (Group 4) Group 1: ARTSS did not differ significantly with different doses of SLIT Groups 2, 3 and 4: 300 IR and 500 IR SLIT doses were significantly more effective than 100 IR and placebo (p ≤ 0.035) ARTSS was comparable in patients with or without grass-pollen asthma, as well as for mono- or polysensitised patients All doses of SLIT were considered safe in the patients investigated |
Cox et al. [34] | Multicentre, randomised, DBPC, parallel-group study Efficacy and safety | 5-grass pollen allergen extract (orchard, meadow, perennial rye, sweet vernal, timothy) | Age 18–65 years Men and women with documented grass pollen-related ARC for at least 2 previous grass pollen seasons, with or without mild asthma | 300 IR (n = 210) Placebo (n = 228) | DCSa Daily symptom scores Symptom-free days during the pollen season Rescue medication use during the pollen season Quality of life (RQLQ) Patients’ global evaluation of treatment Safety | Mean DCS over the pollen period was significantly lower in the 300 IR group vs the placebo group (LS mean difference: 20.13; 95 % CI: 20.19, 20.06; p = 0.0003; relative reduction: 28.2 %; 95 % CI: 13.0 %, 43.4 %) 300 IR 5-grass pollen SLIT was well tolerated Most frequently reported AEs: oral pruritus, throat irritation, nasopharyngitis There were no reports of anaphylaxis |
Wahn et al. [35] | Multinational, randomised, DBPC study | 5-grass pollen allergen extract (orchard, meadow, perennial rye, sweet vernal, timothy) | Age 5–17 years Male and female children with grass pollen-related moderate-to-severe ARC for at least 2 years, with or without mild asthma | 300 IR (n = 131) Placebo (n = 135) | RTSSa Individual symptom scores Rescue medication intake Safety | RTSS for the 300 IR group was significantly improved by 28.0 % (median improvement 39.3 %) vs placebo (p = 0.001) Rescue medication use and proportion of days using rescue medication during the pollen season were both significantly reduced in the 300 IR group vs placebo (p = 0.0064 and p = 0.0146) AEs were generally mild or moderate and in keeping with the known safety profile of SLIT, and no serious side effects were reported |
Didier et al. [36] | Multicentre, randomised, DBPC, parallel-group study Efficacy and safety | 5-grass pollen allergen extract (orchard, meadow, perennial rye, sweet vernal, timothy) | Age 18–50 years Men and women with documented grass pollen-related ARC for ≥2 previous grass pollen seasons, with or without mild asthma | 300 IR (2 M, administered 2 months prior to start of pollen season) (n = 117) 300 IR (4 M, administered 4 months prior to start of pollen season) (n = 127) Placebo (n = 133) | DCSa Individual symptom scores ACS Symptom-free days during the pollen season Rescue medication use during the pollen season Safety | Patients were treated for 3 consecutive years and followed up for 2 years post-treatment During the first post-treatment year, a statistically significant decrease vs placebo in LS mean DCS was noted in patients previously receiving active treatment [300 IR (2 M): −31.1 %, p = 0.0019, 300 IR (4 M): −25.3 %, p = 0.0103) During the second post-treatment year, patients in the 300 IR (4 M) group, but not the 300 IR (2 M) group, showed a statistically significant decrease in LS mean DCS vs placebo (−28.1 %, p = 0.0478) The significant efficacy in the post-treatment years compared favourably with that during the 3 prior years of active treatment A statistically significant difference vs placebo was also noted in secondary efficacy measures in both post-treatment years (except for daily RTSS in year 5) In the absence of any active treatment, the safety profile was similar in the active vs placebo group during either post-treatment year |
Horak et al. [37] | Single-centre, randomised, DBPC, parallel-group study | 5-grass pollen allergen extract (orchard, meadow, perennial rye, sweet vernal, timothy) | Age 18–50 years Men and women with moderate-to-severe seasonal grass pollen-related ARC for ≥2 previous pollen seasons, with or without mild asthma | 300 IR (n = 45) Placebo (n = 44) | ARTSSa Nasal airflow, nasal secretion weight and cutaneous reactivity Safety | A significant treatment effect was achieved after the first (p = 0.0042) and second months (p = 0.0203), which was maintained to the fourth month (p = 0.0007) In the 300 IR group, mean ARTSS (±SD) decreased at each challenge (week 1: 7.40 ± 2.68, month 1: 5.89 ± 2.43, month 2: 5.09 ± 2.09, month 4: 4.85 ± 2.00) Mean ARTSS improved by 29.3 % (median: 33.3 %) vs placebo Most frequent local AEs: oral pruritus, ear pruritus, throat irritation |
Antolin et al. [48] | Multicenter, observational, cross sectional study | 5-grass pollen allergen extract (orchard, meadow, perennial rye, sweet vernal, timothy) | Age ≥6 years Patients with moderat to severe ARC to grass pollen | 591 patients | Patients’ HRQoL Treatment satisfaction | Good level of satisfaction, with an average score of 69.2, on a 0–100 scale (100 being highest satisfaction). HRQoL questionnaires results were also favourable, mean (SD) scores were 1.40 (1.1) in adults, 1.33 (1.1) in adolescents and 1.15 (1.1) in children, with average scores much closer to 0 (no impairment) than to 6 (severe impairment) |
HDM tablet | ||||||
Bergmann et al. 2014 [15] | Randomised DBPC study Efficacy and safety | HDM standardised extract | Age 18–50 years Adults with moderate-to-severe HDM-associated AR for ≥1 year | 500 IR (n = 169) 300 IR (n = 170) Placebo (n = 170) | AAdSSa Individual symptom score Rescue medication use Onset of action Patients’ global evaluation of treatment Safety | Both the 500 IR and 300 tablets significantly reduced mean AAdSS vs placebo by −20.2 % (p = 0.0066) and −17.9 % (p = 0.0150), respectively Efficacy of both doses was maintained during the treatment-free follow-up phase Onset of action was at 4 months Participants’ global evaluation of treatment success was significantly higher in the 500 IR and 300 IR groups vs placebo (p = 0.0206 and p = 0.0001, respectively) AEs were generally application-site reactions, and there were no reports of anaphylaxis |
Okamoto et al. [38] | Multicenter randomized, DBPC, parallel-group design Efficacy and safety | HDM standardised extract | Age 12–64 years Adults with moderate-to-severe HDM-associated AR for ≥2 year | 500 IR (n = 296) 300 IR (n = 315) Placebo (n = 316) | AAdSSa Physicians’ intranasal examination Quality of life Patients’ global evaluation of treatment Safety | Both the 500 IR and 300 tablets significantly reduced mean AAdSS vs placebo by −13.12 % (p < 0.001) and −18.2 % (p < 0.001), respectively Both nasal mucosal swelling and rhinorrhea were markedly and significantly improved in both active treatment groups. In the Japanese RQLQall 3 domains showed a statistically significant improvement difference in the 300 IR group compared to placebo. Participants’ global evaluation of treatment success was significantly higher in the 500 IR and 300 IR groups vs placebo (p = 0.0002 and p < 0.0001, respectively) AEs were generally application-site reactions, and there were no reports of anaphylaxis |
Ferrés et al. [39] | Retrospective, observational, single-centre study Efficacy and safety | HDM standardised extract | Age 6–18 years Patients with AR who were mono-sensitised to HDM, with or without mild asthma | 300 IR (n = 78) | Global assessment of SLIT efficacy measured using a VASa Rhinitis medication consumption score Global asthma score Safety | Significant improvement in allergy severity at 6 months vs baseline (7.3 ± 4.6 vs 4.0 ± 1.7 cm on the VAS, respectively; p < 0.001), which was maintained throughout the 4-year follow-up period Symptomatic medication use was significantly reduced in the first 6 months vs baseline (0.8 ± 1.6 points vs 4.6 ± 2.5 points, respectively; p < 0.001) and remained very low until the end of follow-up SLIT was well tolerated, and no anaphylactic or life-threatening reactions were reported |
SLIT drops | ||||||
5-grass pollen drops | ||||||
Ott et al. [17] | Randomised, DBPC, parallel-group, multicentre study Efficacy and safety | 5-grass pollen extract (orchard, meadow, perennial rye, sweet vernal, and timothy grasses) | Age 7.9–64.7 years Men and women with grass pollen-related ARC using symptomatic medication during the grass pollen season, with or without mild asthma | 300 IR (n = 99) Placebo (n = 46) | Combined symptom and rescue medication scorea Individual symptom scores Safety | Median combined scores decreased by 44.7 % in the SLIT group and 14.7 % in the placebo group vs baseline, by the third pollen season (p = 0.0019) Similar changes were observed for symptom scores, with a successive decrease of 39.7 % (SLIT) and fluctuations between +13.6 and −1.5 % for placebo (p < 0.05) over the 3 pollen seasons Combined score (p = 0.0508) and symptom score improvements (p = 0.0144) with SLIT continued during follow-up SLIT was well tolerated, and no serious systemic or anaphylactic reactions were reported |
Birch pollen drops | ||||||
Worm et al. [19] | Randomized, DBPC, multicentre study Efficacy and safety | Birch pollen allergen standardised extract | Age 18–65 years Men and women with birch pollen-related ARC for ≥2 previous birch pollen seasons that required intake of symptomatic treatments, with or without OAS, with or without mild asthma | 300 IR (n = 283) Placebo (n = 289) | AAdSS over the second pollen seasona AAdSS over the first pollen season Individual symptom scores Rescue medication use during the pollen season Quality of life (RQLQ) Safety | LS mean AAdSS was significantly lower in the 300 IR group than in the placebo group (LS mean difference -2.04, 95 % CI [−2.69, −1.40], (p < 0.0001) over the second pollen season (relative reduction of 30.6 %) Improvements in AAdSS were similar in patients with and without OAS (relative LS mean differences of −33.6 and −28.4 %, respectively) A significant reduction in LS mean AAdSS was also observed over the first pollen season SLIT was well tolerated, and no anaphylaxis was reported Most frequently reported AEs: application-site reactions (oral pruritus), throat irritation, mouth edema |
Grass and tree pollen drops | ||||||
Seidenberg et al. 2009 [44] | Large observational study Safety | 5-grass pollen (cocksfoot, meadow, rye, sweet vernal, and timothy grasses) or tree pollen (birch, alder, and hazel) allergen standardised extract | Age 5–17 years Children and adolescents with AR for ≥1 year due to grass or tree pollen, with or without mild to moderate asthma | Ultrarush titration high-dose 300 IR SLIT (n = 193) | Frequency and intensity (mild, moderate, severe) of expected local, gastrointestinal, and generalised AEsa Patients’ and investigators’ global assessment of tolerability | Ultrarush titration was well tolerated During ultrarush titration, 60 patients (31 %) reported 117 predominantly mild and local AEs, which resolved within 150 min During the maintenance phase, 562 AEs were reported Most frequently reported local events: oral pruritus, burning sensation, lip or tongue swelling, gastrointestinal symptoms Most frequently reported systemic events: rhinoconjunctivitis, asthma There was 1 clinically significant asthma event in an 11-year old boy with known asthma, who resumed SLIT after 4 days |
HDM drops | ||||||
Wang et al. [18] | DBPC, randomised study Efficacy and safety | HDM standardised extract | Age 14–50 years Patients with mild or moderate, persistent, HDM-induced asthma for ≥1 year | 300 IR (n = 308) Placebo (n = 157) | Well-controlled asthma for ≥16 of the last 20 weeks of treatmenta Totally controlled asthma Safety | Well-controlled asthma was achieved by 85.4 and 81.5 % of patients in the 300 IR and placebo groups, respectively (p = 0.244) Post hoc analysis by asthma severity found significant clinical benefits in actively treated subjects with moderate asthma at baseline (n = 175), but not those with mild asthma: Greater achievement of well-controlled asthma (300 IR: 80.5 %, placebo: 66.1 %; p = 0.021) and totally controlled asthma (300 IR: 54.0 %, placebo: 33.9 %; p = 0.008) Higher percentage of patients with an asthma control questionnaire score <0.75 (300 IR: 56.6 %, placebo: 40.0 %; p = 0.039) Greater mean reduction in inhaled corticosteroid use (300 IR: 218.5 μg, placebo: 126.2 μg; p = 0.004) 300 IR was well tolerated, and no treatment-related serious AEs were reported |
Retropsective, multicenter, observational study | HDM standardised extract | Age ≥5 years Children and adults with respiratory allergy and proven sensitization to HDM | 1289 patients | Physician perception of patient satisfaction Compliance with treatment | Over 84 % of adult and pediatric patients with AR (with or without asthma) were satisfied and adhered to their treatment | |
Grass and tree pollen, and HDM drops | ||||||
Corzo et al. 2012 [45] | Multicentre, observational, epidemiological study Safety | 5-grass pollen, olive tree pollen or HDM standardised extracts | Age 5–15 years Children and adolescents with AR, ARC and/or bronchial asthma due to grass pollen, olive pollen and/or HDM | 300 IR (n = 74) | Tolerability and occurrence of local oral, systemic and gastrointestinal AEsa | After the first administration, 22 % of children had self-limiting pruritus, 4 % had moderate OAS (intense oropharyngeal itching) and 1 patient had diffuse abdominal pain No systemic reactions were recorded No patients reported problems during the maintenance phase, and there were no discontinuations of therapy |