The current role of sublingual immunotherapy in the treatment of allergic rhinitis in adults and children

High-dose sublingual immunotherapy in patients with uncontrolled allergic rhinitis sensitized to pollen: a real-life clinical study

BACKGROUND

High-dose pollen sublingual immunotherapy (SLIT) is indicated in patients with moderate to severe allergic rhinitis (AR), especially those who are unable to control their disease with pharmacotherapy. We explore the use of high-dose SLIT in patients with severe AR and sensitized to pollen, in real-life clinical practice. We also analyzed the effect on asthma.

METHODS

This was a prospective observational study conducted at the Allergy outpatient clinic at Hotel Dieu de France Hospital (HDF), Beirut, Lebanon. The cohort, composed of 118 patients between 7 and 55 years old, was regularly evaluated at inclusion, at 12 months, and at 36 months. Fifty-five percent of AR patients had associated controlled asthma. Patients received a standardized pollen extract (Staloral 300IR). The pollen combination was 1 to 3 pollens, the most commonly used were Parietaria judaica, Cupressaceae, 5 grasses, and Oleaceae. In a previous study, those were the main allergenic pollens correlated to AR in the same population. Global assessment of the effect of SLIT was measured using a rhinitis total symptom score (RTSS), a rhinitis medication consumption score (RMCS), a global asthma score (ASS), and an asthma medication consumption score (AMCS).

RESULTS

Using a t test we found that the average scores at inclusion, 12 months, and 36 months, respectively, were as follows: RTSS: 31.32, 16.39 (p < 0.041), and 13.35 (p < 0.041); RMCS: 6.96, 1.96 (p < 0.0162), and 1.61 (p < 0.0162); ASS: 4.62, 1.96 (p < 0.0005), and 1.33 (p < 0.0005); and AMCS: 2.35, 0.78 (p < 0.0005), and 0.7 (p < 0.0005).

CONCLUSION

Our study showed favorable results of SLIT to aeroallergens in patients with uncontrolled AR. The effect is also applicable to the subgroup of patients suffering from concomitant, controlled asthma.

Omalizumab, an anti-immunoglobulin E antibody: state of the art

A large number of trials show that the anti-immunoglobulin (Ig) E antibody omalizumab is very effective in patients with severe allergic asthma. This is acknowledged in consensus documents. The drug also has a good safety profile and a pharmacoeconomic advantage due to a reduction in the number of hospitalizations for asthma attacks. In recent years, some studies have shown that omalizumab is effective also in nonallergic asthma. Effects on the complex signaling mechanisms leading to activation of effector cells and to mediator release may account for this outcome. Indeed, omalizumab has been reported to be effective in a number of IgE-mediated and non-IgE-mediated disorders. Concerning the former, clinical efficacy has been observed in rhinitis, allergic bronchopulmonary aspergillosis, latex allergy, atopic dermatitis, allergic urticaria, and anaphylaxis. In addition, omalizumab has been demonstrated to be able to prevent systemic reactions to allergen immunotherapy, thus enabling completion of treatment in patients who otherwise would have to stop it. Concerning non-IgE-mediated disorders, omalizumab has been reported to be effective in nasal polyposis, autoimmune urticaria, chronic idiopathic urticaria, physical urticaria, idiopathic angioedema, and mastocytosis. Current indications for treatment with omalizumab are confined to severe allergic asthma. Consequently, any other prescription can only be off-label. However, it is reasonable to expect that the use of omalizumab will be approved for particularly important indications, such as anaphylaxis, in the near future.

5-grass pollen tablets achieve disease control in patients with seasonal allergic rhinitis unresponsive to drugs: a real-life study

Background

An important subpopulation in allergic rhinitis is represented by patients with severe form of disease that is not responsive to drug treatment. It has been reported that grass pollen subcutaneous immunotherapy is effective in drug-resistant patients. In a real-life study, we evaluated the efficacy of 5-grass pollen tablets in patients with grass pollen-induced allergic rhinitis not responsive to drug therapy.

Methods

We carried out this multicenter observational study in adults and adolescents with grass-induced allergic rhinitis not responsive to drug therapy who were treated for a year with 5-grass pollen tablets. Clinical data collected before and after sublingual immunotherapy (SLIT) included Allergic Rhinitis and its Impact on Asthma (ARIA) classification of allergic rhinitis, response to therapy, and patient satisfaction.

Results

Forty-seven patients entered the study. By ARIA classification, three patients had moderate to severe intermittent allergic rhinitis, ten had mild persistent allergic rhinitis, and 34 had moderate to severe persistent allergic rhinitis. There were no cases of mild intermittent allergic rhinitis before SLIT. After SLIT, 33 patients had mild intermittent allergic rhinitis, none had moderate to severe intermittent allergic rhinitis, seven had mild persistent allergic rhinitis, and seven had moderate to severe persistent allergic rhinitis. The mean medication score decreased from 4.2±1.3 before to 2.4±2.0 after SLIT (P<0.01), representing a reduction of 42%. The response to treatment before SLIT was judged as poor by 70% of patients and very poor by 30%. Patient satisfaction was significantly increased after SLIT (P<0.01).

Conclusion

In real life, most patients with grass pollen-induced allergic rhinitis not responsive to drug treatment can achieve control of the condition with one season of treatment using 5-grass pollen tablets.

Safety considerations in the management of allergic diseases: focus on antihistamines

OBJECTIVE

To conduct a systematic review of evidence supporting the safety profiles of frequently used oral H(1)-antihistamines (AHs) for the treatment of patients with histamine-release related allergic diseases, e.g. allergic rhinitis and urticaria, and to compare them to the safety profiles of other medications, mostly topical corticosteroids and leukotriene antagonists (LTRA).

RESEARCH DESIGN AND METHODS

Systematic search of the published literature (PubMed) and of the regulatory authorities databases (EMA and FDA) for oral AHs.

RESULTS

Similarly to histamine, antihistamines (AHs) have organ-specific efficacy and adverse effects. The peripheral H(1)-receptor (PrH1R) stimulation leads to allergic symptoms while the brain H(1)-receptor (BrH1R) blockade leads to somnolence, fatigue, increased appetite, decreased cognitive functions (impaired memory and learning), seizures, aggressive behaviour, etc. First-generation oral AHs (FGAHs) inhibit the effects of histamine not only peripherally but also in the brain, and additionally have potent antimuscarinic, anti-α-adrenergic and antiserotonin effects leading to symptoms such as visual disturbances (mydriasis, photophobia, and diplopia), dry mouth, tachycardia, constipation, urinary retention, agitation, and confusion. The somnolence caused by FGAHs interferes with the natural circadian sleep-wake cycle and therefore FGAHs are not suitable to be used as sleeping pills. Second-generation oral AHs (SGAHs) have proven better safety and tolerability profiles, much lower proportional impairment ratios, with at least similar if not better efficacy, than their predecessors. Only SGAHs, and especially those with a proven long-term (e.g., ≥12 months) clinical safety, should be prescribed for young children. Evidence exist that intranasally applied medications, like intranasal antihistamines, have the potential to reach the brain and cause somnolence.

CONCLUSIONS

Second-generation oral antihistamines are the preferred first-line treatment option for allergic rhinitis and urticaria. Patients taking SGAHs report relatively little and mild adverse events even after long-term continuous treatments. An antihistamine should ideally possess high selectivity for the H(1)-receptor, high PrH1R occupancy and low to no BrH1R occupancy.

A comparison of attrition rates in patients undergoing sublingual immunotherapy vs subcutaneous immunotherapy

BACKGROUND

Effective allergy immunotherapy (IT) requires patient compliance. Numerous studies have shown high noncompliance rates in patients undergoing IT. For patients enrolled in subcutaneous IT (SCIT), noncompliance rates were noted to range from 11% to 50%, whereas sublingual IT (SLIT) patients had noncompliance rates ranging from 3% to 25%. Comparing noncompliance rates is difficult because noncompliance in SCIT is defined as withdrawal from therapy, whereas in SLIT it is considered poor adherence to daily administration. The aim of this study was to compare attrition rates in patients enrolled in SCIT vs SLIT, as well as major factors leading to termination of IT.

METHODS

We retrospectively compared attrition rates, IT duration, and reasons for termination between patients enrolled in SCIT (n = 139) and SLIT (n = 78), over a 4-year period.

RESULTS

Attrition rates for SCIT and SLIT were 45% and 41%, respectively (p = 0.669). No significant difference in duration of IT was observed between the groups (≤1 month, p = 0.079; 1-2 months, p = 0.486; 2-3 months, p = 0.165; 3-6 months, p = 0.575; 6-12 months, p = 0.361; 12-24 months, p = 1.000; and ≥24 months, p = 0.258). Among reasons cited for discontinuing IT, SCIT patients reported inconvenience (p = 0.001), whereas SLIT patients indicated efficacy concerns (p = 0.022) as the major basis for withdrawal.

CONCLUSION

No significant difference was observed in attrition rates between SCIT and SLIT. While there was no significant difference in duration of IT prior to withdrawal, there was a trend toward earlier withdrawal in SCIT patients. The reasons for withdrawal, however, were considerably different between the 2 groups.

Therapeutic effects and biomarkers in sublingual immunotherapy: a review

Immunotherapy is considered to be the only curative treatment for allergic diseases such as pollinosis, perennial rhinitis, asthma, and food allergy. The sublingual route is widely applied for immunotherapy for allergy, instead of the conventional administration by subcutaneous route. A recent meta-analysis of sublingual immunotherapy (SLIT) has shown that this approach is safe, has positive clinical effects, and provides prolonged therapeutic effects after discontinuation of treatment. However, the mechanism of SLIT and associated biomarkers are not fully understood. Biomarkers that change after or during SLIT have been reported and may be useful for response monitoring or as prognostic indicators for SLIT. In this review, we focus on the safety, therapeutic effects, including prolonged effects after treatment, and new methods of SLIT. We also discuss response monitoring and prognostic biomarkers for SLIT. Finally, we discuss immunological mechanisms of SLIT with a focus on oral dendritic cells and facilitated antigen presentation.