Carrageenan-Containing Nasal Spray Alleviates Allergic Symptoms in Participants with Grass Pollen Allergy: A Randomized, Controlled, Crossover Clinical Trial

Purpose

Nonpharmacological, barrier-forming nasal sprays are used to manage symptoms of allergic rhinitis. We aim to evaluate the safety and effectiveness of Callergin (investigational product, IP), a nasal spray containing barrier-forming iota-carrageenan, in the treatment of allergic rhinitis (AR).

Methods

In this randomized, controlled, crossover trial, adults with grass pollen allergy underwent a treatment sequence with IP, VisAlpin (comparator product, CP), and no treatment in random order. Treatment blocks consisted in prophylactic administration of the assigned treatment or no treatment, followed by a 3-hr allergen exposure, and were separated by a washout period of 7 days. Primary endpoint was a mean change from baseline in "Total Nasal Symptom Score" (TNSS, sum of rhinorrhea, itching, sneezing, and congestion scores) over 3 hr, recorded every 15 min during the challenge period.

Results

A total of 42 participants underwent randomization. Exposure to grass pollen for 3 hr induced a notable TNSS increase from baseline in all participants at all times. Mean TNSS change from baseline over 3 hr was lower when participants received IP compared to no treatment, although the difference did not reach statistical significance (untreated 6.96 ± 2.30; IP 6.59 ± 1.93; difference 0.37 points [95% CI (confidence interval) -0.17 to 0.91]; p=0.170). In a post-hoc analysis, mean TNSS at 3 hr was significantly reduced after IP treatment compared to no treatment (untreated 8.29 ± 2.64; IP 7.70 ± 2.56; difference 0.60 points [95% CI -0.10 to 1.29] p=0.028). While all individual nasal symptoms contributed to this effect, rhinorrhea (p=0.013) and congestion (p=0.076) contributed most. Consistently, nasal secretion weight was slightly reduced with IP treatment (p=0.119). IP was safe and well-tolerated, with similar incidence of adverse events across treatment groups.

Conclusion

Prophylactic treatment with the iota-carrageenan nasal spray IP is safe, well-tolerated, and alleviates nasal allergy symptoms in adults with grass pollen-induced AR.

Trial Registration

NCT04531358.

Technical standards in allergen exposure chambers worldwide - an EAACI Task Force Report

Allergen exposure chambers (AECs) can be used for controlled exposure to allergenic and non-allergenic airborne particles in an enclosed environment, in order to (i) characterize the pathological features of respiratory diseases and (ii) contribute to and accelerate the clinical development of pharmacological treatments and allergen immunotherapy for allergic disease of the respiratory tract (such as allergic rhinitis, allergic rhinoconjunctivitis, and allergic asthma). In the guidelines of the European Medicines Agency for the clinical development of products for allergen immunotherapy (AIT), the role of AECs in determining primary endpoints in dose-finding Phase II trials is emphasized. Although methodologically insulated from the variability of natural pollen exposure, chamber models remain confined to supporting secondary, rather than primary, endpoints in Phase III registration trials. The need for further validation in comparison with field exposure is clearly mandated. On this basis, the European Academy of Allergy and Clinical Immunology (EAACI) initiated a Task Force in 2015 charged to gain a better understanding of how AECs can generate knowledge about respiratory allergies and can contribute to the clinical development of treatments. Researchers working with AECs worldwide were asked to provide technical information in eight sections: (i) dimensions and structure of the AEC, (ii) AEC staff, (iii) airflow, air processing, and operating conditions, (iv) particle dispersal, (v) pollen/particle counting, (vi) safety and non-contamination measures, (vii) procedures for symptom assessments, (viii) tested allergens/substances and validation procedures. On this basis, a minimal set of technical requirements for AECs applied to the field of allergology is proposed.

IgE recognition of the house dust mite allergen Der p 37 is associated with asthma

BACKGROUND

House dust mite (HDM) allergens are major elicitors of allergic reactions worldwide.

OBJECTIVE

Identification, characterization, and evaluation of diagnostic utility of a new important HDM allergen was performed.

METHODS

A cDNA coding for a new Dermatophagoides pteronyssinus (Dp) allergen, Der p 37, was isolated from a Dp expression library with allergic patients' IgE antibodies. Recombinant Der p 37 (rDer p 37) expressed in Escherichia coli was purified, then characterized by mass spectrometry, circular dichroism, and IgE reactivity by ImmunoCAP ISAC technology with sera from 111 clinically defined HDM-allergic patients. The allergenic activity of rDer p 37 was studied by basophil activation and CD4⁺ T-cell responses by carboxyfluorescein diacetate succinimidyl ester dilution assays. Specific antibodies raised against rDer p 37 were used for the ultrastructural localization of Der p 37 in mites by immunogold transmission electron microscopy.

RESULTS

Der p 37, a 26 kDa allergen with homology to chitin-binding proteins, is immunologically distinct from Der p 15, 18, and 23. It is located in the peritrophic membrane of fecal pellets. Der p 37 reacted with IgE antibodies from a third of HDM-allergic patients and induced specific basophil- and CD4⁺ T-cell activation. Der p 37 IgE-positive patients had significantly higher IgE levels to major HDM allergens, reacted with more HDM allergens, and had a higher risk (odds ratio = 3.1) of asthma compared to Der p 37-negative patients.

CONCLUSIONS

Der p 37, a new Dp allergen recognized by a third of HDM-allergic patients, may serve as a surrogate marker for severe HDM sensitization and asthma.

IgE Epitopes of the House Dust Mite Allergen Der p 7 Are Mainly Discontinuous and Conformational

Background

Several studies indicate that Der p 7 is an important and clinically relevant allergen of Dermatophagoides pteronyssinus which should be included in vaccines for treatment of house dust mite (HDM) allergy. Aim of this study was to characterize the IgE epitopes of Der p 7.

Methods

Recombinant Der p 7 was expressed and purified, analyzed for fold by circular dichroism and tested for its allergenic activity by basophil activation. Seven overlapping, surface-exposed peptides (P1–P7) with a length of 27 to 37 amino acids, which spanned the Der p 7 sequence, were synthesized and tested for IgE reactivity and allergenic activity by basophil activation assay. Carrier-bound peptides were studied for their ability to induce allergen-specific IgG antibodies in rabbits. Peptide-specific antibodies were used to inhibit allergic patients` IgE binding to Der p 7 by ELISA for mapping of IgE epitopes.

Results

rDer p 7 showed high allergenic activity comparable with Der p 5, Der p 21, and Der p 23. None of the seven tested peptides showed any IgE reactivity or allergenic activity when tested with HDM- allergic patients indicating lack of sequential IgE epitopes on Der p 7. IgE inhibition experiments using anti-peptide specific IgGs and molecular modeling enabled us to identify discontinuous, conformational IgE epitopes of Der p 7.

Conclusion and Clinical Relevance

IgE epitopes of Der p 7 belong to the conformational and discontinuous type whereas sequential Der p 7 peptides lack IgE reactivity. It should thus be possible to construct hypoallergenic vaccines for Der p 7 based on carrier-bound allergen peptides.

Expression in Escherichia coli and Purification of Folded rDer p 20, the Arginine Kinase From Dermatophagoides pteronyssinus: A Possible Biomarker for Allergic Asthma

Arginine kinase (AK) was first identified as an allergen in the Indian-meal moth and subsequently shown to occur as allergen in various invertebrates and shellfish. The cDNA coding for AK from the house dust mite (HDM) species Dermatophagoides pteronyssinus, Der p 20, has been isolated, but no recombinant Der p 20 (rDer p 20) allergen has been produced and characterized so far. We report the expression of Der p 20 as recombinant protein in Escherichia coli. rDer p 20 was purified and shown to be a monomeric, folded protein by size exclusion chromatography and circular dichroism spectroscopy, respectively. Using AK-specific antibodies, Der p 20 was found to occur mainly in HDM bodies, but not in fecal particles. Thirty percent of clinically well-characterized HDM allergic patients (n = 98) whose immunoglobulin E (IgE) reactivity profiles had been determined with an extensive panel of purified HDM allergens (Der f 1, 2; Der p 1, 2, 4, 5, 7, 10, 11, 14, 15, 18, 21, 23 and 37) showed IgE reactivity to Der p 20. IgE reactivity to Der p 20 was more frequently associated with lung symptoms. AKs were detected in several invertebrates with specific antibodies and Der p 20 showed IgE cross-reactivity with AK from shrimp (Litopenaeus vannamei). Thus, Der p 20 is a cross-reactive HDM allergen and may serve as a diagnostic marker for HDM-induced lung symptoms such as asthma.

Quantification, epitope mapping and genotype cross-reactivity of hepatitis B preS-specific antibodies in subjects vaccinated with different dosage regimens of BM32

Background

Chronic hepatitis B virus (HBV) infections are a global health problem. There is a need for therapeutic strategies blocking continuous infection of liver cells. The grass pollen allergy vaccine BM32 containing the preS domain of the large HBV surface protein (LHBs) as immunogenic carrier induced IgG antibodies in human subjects inhibiting HBV infection in vitro. Aim of this study was the quantification, epitope mapping and investigation of HBV genotype cross-reactivity of preS-specific antibodies in subjects treated with different dosage regimens of BM32

Methods

Hundred twenty eight grass pollen allergic patients received in a double-blind, placebo-controlled trial five monthly injections of placebo (aluminum hydroxide, n= 34) or different courses of BM32 (2 placebo + 3 BM32, n= 33; 1 placebo + 4 BM32, n= 30; 5 BM32, n= 31). Recombinant Escherichia coli-expressed preS was purified. Overlapping peptides spanning preS and the receptor-binding sites from consensus sequences of genotypes A–H were synthesized and purified. Isotype (IgM, IgG, IgA, IgE) and IgG subclass (IgG₁-IgG₄) responses to preS and peptides were determined by ELISA at baseline, one and four months after the last injection. IgG₁ and IgG₄ subclass concentrations specific for preS and the receptor-binding site were measured by quantitative ELISA.

Findings

Five monthly injections induced the highest levels of preS-specific IgG consisting mainly of IgG₁ and IgG₄, with a sum of median preS-specific IgG₁ and IgG₄ concentrations of >135 μg/ml reaching up to 1.8 mg/ml. More than 20% of preS-specific IgG was directed against the receptor-binding site. BM32-induced IgG cross-reacted with the receptor-binding domains from all eight HBV genotypes A-H.

Interpretation

BM32 induces high levels of IgG₁ and IgG₄ antibodies against the receptor binding sites of all eight HBV genotypes and hence might be suitable for therapeutic HBV vaccination.

Funding

This study was supported by the PhD program IAI (KPW01212FW), by Viravaxx AG and by the Danube-ARC funded by the Government of Lower Austria. Rudolf Valenta is a recipient of a Megagrant of the Government of the Russian Federation, grant No 14.W03.31.0024.

Fast effectiveness of a solubilized low-dose budesonide nasal spray in allergic rhinitis

Background

Budesonide, a poorly water‐soluble corticosteroid, is currently marketed as a suspension. Budesolv is a novel aqueous formulation containing dissolved budesonide showing increased local availability in preclinical models. Budesolv contains ~85% less corticosteroid than the marketed comparator.

Objective

The study (EudraCT:2018‐001324‐19) was designed to assess non‐inferiority of Budesolv compared to Rhinocort® Aqua 64 (RA) and early onset of action.

Methods

In a three‐way cross‐over double‐blinded randomized trial, Budesolv 10 was compared to RA and placebo in grass pollen allergic rhinoconjunctivitis volunteers (n = 83 (ITT); n = 75 (PP)). On day 1, participants entered the Vienna Challenge Chamber (VCC) for 6 hours; first treatment took place at 1:45 hours after entry. Participants treated themselves for further 6 days; on day 8, the last treatment was applied before entering the VCC. Subjective symptom scores, nasal airflow and nasal secretion were measured regularly during allergen challenge.

Results

Budesolv 10 was equally effective compared to RA with respect to TNSS and nasal airflow after eight days of treatment with a strongly reduced dose (more than 80% reduction). After first dose, only Budesolv 10 showed a significant reduction of nasal and respiratory symptoms starting 90 minutes (P < .05) and 15 minutes (P < .05) after application onwards, respectively, demonstrating an early onset of efficacy. A clinically significant 1 point reduction in nasal symptom score was reached at 195 minutes (P < .05) after application.

Conclusions and clinical relevance

The novel preservative‐free, aqueous low‐dose budesonide formulation is highly efficacious even after an initial single treatment. Thus, Budesolv 10 appears to be an effective acute treatment for allergic rhinitis as well as for AR comorbidities like mild asthma and conjunctivitis.

A novel formulation of budesonide nasal spray (Budesolv 10) potentiates clinical performance in grass pollen allergic patients

Objective

Purpose of this DBPC study was to evaluate onset of action and non-inferiority of a novel low dose aqueous solution of Budesonide (“Budesolv 10μg”) to Rhinocort® aqua 64μg (RA) in adult grass pollen allergic patients.

Methods

Budesonide, a poorly water-soluble corticosteroid, currently marketed as suspension, was reformulated to enhance solubility and local concentration on the target mucosa. Subjects received Budesolv, the market comparator RA and placebo once daily for 8 days. Allergic symptoms were induced by 6h grass pollen challenges in the Vienna Challenge Chamber at days 1 and 8 of each treatment period. First dose was applied after 1:45h to evaluate onset of action of either treatment. Nasal, ocular, asthma symptoms and objective measures of nasal secretion and nasal obstruction were evaluated. A 95% confidence interval (CI) was calculated for difference in means between active treatments. Non-inferiority was stated if the upper limit of the CI did not exceed 115% of the reference. Onset of action was defined as first time point when the difference in nasal symptoms change from baseline between active treatment and placebo was p&lt;0.05.

Results

75 patients concluded the study per protocol. The primary endpoint (TNSS; sum of obstruction, itch, sneeze and rhinorrhoea) was met proving non-inferiority of Budesolv compared to RA. A significant difference between Budesolv and placebo was shown for TNSS 2.45 h and for total asthma score 2 h after first dose. On day 8 Budesolv 10μg was significantly better than placebo for all parameters evaluated.

Conclusion

Non-inferiority of Budesolv compared to Rhinocort® was shown on day 8 of treatment. Early onset of action within 3h after first dose was evident for Budesolv only.

Cetirizine inhibits gender-specific blood cell dynamics upon allergen contact in allergic rhinitis

IgE-mediated inflammatory responses upon allergen contact in allergic rhinitis (AR) are associated with rapid alterations of circulating blood cell numbers detectable in a complete blood count (CBC). Aim of this study was to evaluate whether intake of antihistamines may modulate allergen-induced CBC dynamics in male and female patients. A total of N = 112 specific allergen challenges were performed in otherwise healthy AR subjects. Seventy-two (n = 72) subjects received placebo and forty (n = 40) received cetirizine (H1-receptor antagonist) per os prior to allergen exposure in a randomized, double-blind trial at the Vienna Challenge Chamber (VCC); a subgroup of twenty-five (n = 25) subjects received cetirizine and placebo on different study days (parallel group). Blood samples and symptom scores were taken at baseline and immediately after 6 h of airway challenge simulating ambient allergen contact. Female sex was associated with a pronounced circulating monocyte increase (p < .01) and male sex with an eosinophil decrease (p < .05) in the placebo group, but not in cetirizine treated subjects. The significant increase in segmented neutrophils (p < .001) and decrease in circulating erythrocytes (p < .01) upon allergen challenge was less prominent after cetirizine intake in both sexes. A more prominent thrombocyte increase in female subjects (p < .05) was noted upon allergen exposure, regardless of prior cetirizine intake. Cetirizine inhibited the mobilization of neutrophils, lymphocytes and decline in erythrocyte numbers, but did not affect thrombocyte increase upon allergen challenge. It further diminished gender-specific blood cell dynamics. Overall, as reflected in a simple CBC, cetirizine critically diminished immediate and late innate immune responses subsequent to allergen exposure.

Clinical efficacy of sublingual immunotherapy is associated with restoration of steady-state serum lipocalin 2 after SLIT: a pilot study

Background

So far, only a few biomarkers in allergen immunotherapy exist that are associated with a clinical benefit. We thus investigated in a pilot study whether innate molecules such as the molecule lipocalin-2 (LCN2), with implications in immune tolerance demonstrated in other fields, may discriminate A) between allergic and non-allergic individuals, and B) between patients clinically responding or non-responding to sublingual allergen immunotherapy (SLIT) with house dust mite (HDM) extract. Moreover, we assessed haematological changes potentially correlating with allergic symptoms.

Methods

LCN2-concentrations were assessed in sera of healthy and allergic subjects (n = 126) as well as of house dust mite (HDM) allergics before and during HDM- sublingual immunotherapy (SLIT) in a randomized, double-blind, placebo-controlled trial for 24 weeks. Sera pre-SLIT (week 0), post-SLIT (week 24) and 9 months after SLIT were assessed for LCN2 levels and correlated with total nasal symptom scores (TNSS) obtained during chamber challenge at week 24 in patients receiving HDM- (n = 31) or placebo-SLIT (n = 10).

Results

Allergic individuals had significantly (p < 0.0001) lower LCN2-levels than healthy controls. HDM-allergic patients who received HDM-SLIT showed a significant increase in LCN2 9 months after termination of HDM-SLIT (p < 0.001), whereas in subjects receiving placebo no increase in LCN2 was observed. Among blood parameters a lower absolute rise in the lymphocyte population (p < 0.05) negatively correlated with symptom improvement (Pearson r 0.3395), and a lower relative increase in the neutrophils were associated with improvement in TNSS (p < 0.05). LCN2 levels 9 months after immunotherapy showed a low positive correlation with the relative improvement of symptoms (Pearson r 0.3293). LCN2-levels 9 months off-SLIT were significantly higher in patients whose symptoms improved during chamber challenge than in those whose symptoms aggravated (p < 0.01).

Conclusion

Serum LCN2 concentrations 9 months off-SLIT correlated with clinical reactivity in allergic patients. An increase in the LCN2 levels 9 months after HDM-SLIT was associated with a clinical benefit. Serum LCN2 may thus contribute to assess clinical reactivity in allergic patients.

Trial registration

Part of the data were generated from clinicaltrials.gov Identifier NCT01644617.

Pru p 3, a marker allergen for lipid transfer protein sensitization also in Central Europe

In the Mediterranean area, lipid transfer proteins (LTPs) are important causes of plant‐food allergies often associated with severe allergic reactions. There, peach LTP (Pru p 3) seems to be the primary sensitizer, whereas in Central Europe, little is known about the importance of LTP sensitization. In this region, allergen extract‐based diagnosis is often complicated by co‐sensitization to Bet v 1, the major birch pollen allergen, its cross‐reactive food allergens, and profilins. We investigated the role of LTP sensitization in Central European patients displaying strong allergic reactions to plant‐derived food. Analysis of IgE reactivity revealed that ten of thirteen patients were sensitized to Pru p 3, nine to Bet v 1, and two to profilin. Our results showed that LTP sensitization represents a risk factor for severe allergic symptoms in Central Europe. Furthermore, the strong IgE reactivity detected in immunoblots of plant‐food extracts indicated that Pru p 3 can be used as a marker allergen for LTP sensitization also in Central European patients.

Long-term effects of a house dust mite sublingual immunotherapy tablet in an environmental exposure chamber trial

BACKGROUND

Treatment with SQ house dust mite (HDM) sublingual immunotherapy (SLIT) tablet is effective for HDM respiratory allergic disease, but data on long-term effects are lacking.

OBJECTIVE

Post hoc analyses were conducted to determine the long-term effect of SQ HDM SLIT-tablet on nasal, ocular, and cough symptoms 1 year after discontinuation of treatment.

METHODS

Study participants underwent environmental exposure chamber (EEC) challenges at baseline and week 24 in a randomized, placebo-controlled, double-blind trial (NCT01644617) during which participants received daily 12 SQ-HDM, 6 SQ-HDM, or placebo for 24 weeks. Asthma had to be stable, well controlled, and nonsevere. The mean total asthma symptom score (TASS; sum of 3 symptoms: cough, wheeze, and dyspnea) during baseline and week 24 EEC challenge was analyzed in all participants who completed the trial (n = 106). Approximately 1 year after trial completion, another EEC challenge was conducted in a subset of participants (n = 51). Total nasal symptom score (sum of 4 symptoms), total ocular symptom score (sum of 2 symptoms), and cough were assessed.

RESULTS

Compared with baseline and end-of-treatment values, sustained improvement of all symptoms assessed at the 1-year follow-up EEC challenge was evident in participants treated with 12 SQ-HDM. Results with 6 SQ-HDM were less notable. After 24 weeks of 12 SQ-HDM, TASS during EEC challenge was improved 65% vs baseline; at 1-year follow-up, cough was improved 57% vs baseline.

CONCLUSION

Persistent improvement of nasal and ocular symptoms was observed up to 1 year after completing 24 weeks of 12 SQ-HDM treatment. Beneficial effects on cough were also observed.

TRIAL REGISTRATION

clinicaltrials.gov Identifier NCT01644617.

Sublingual house dust mite immunotherapy has no impact on decrease of circulating erythrocytes upon airway allergen challenge in allergic rhinitis

House dust mite (HDM) allergy is a predominant cause for perennial allergic rhinitis (AR) in Europe. We recently reported that circulating erythrocyte numbers decrease after airway allergen challenge in a murine asthma model and in grass-pollen sensitized AR subjects. Consequently, we aimed to evaluate these findings in HDM sensitized AR subjects and the influence of preceding allergen immunotherapy. Seventy-seven (age 26.8 ± 7.3 years; 54.5% female) HDM-allergic rhinitis subjects previously enrolled in a randomized, monocentric sublingual immunotherapy (SLIT) trial at the Vienna Challenge Chamber (VCC) were included. Subjects had either received placebo (n = 22), low-dose HDM (n = 29) or high-dose HDM specific sublingual immunotherapy (n = 26) daily for 24 weeks. Blood sampling was performed before and after 6 hours of HDM allergen exposure. Overall, specific airway allergen challenge resulted in a significant decrease in circulating erythrocytes and hematocrit (p < 0.001), and elevation of leukocytes (p < 0.001), particularly segmented neutrophils (p < 0.001). Gender had no significant effect on the observed changes in circulating blood cells. Erythrocytes decreased and neutrophil counts increased significantly after airway allergen challenge regardless of preceding immunotherapy. These findings imply a rapid systemic mobilization of neutrophils occurring within immediate type hypersensitivity response upon a specific allergen challenge, which is possibly inversely linked with the erythrocyte numbers.

Mechanisms, safety and efficacy of a B cell epitope-based vaccine for immunotherapy of grass pollen allergy

BACKGROUND

We have developed a recombinant B cell epitope-based vaccine (BM32) for allergen-specific immunotherapy (AIT) of grass pollen allergy. The vaccine contains recombinant fusion proteins consisting of allergen-derived peptides and the hepatitis B surface protein domain preS as immunological carrier.

METHODS

We conducted a randomized, double-blind, placebo-controlled AIT study to determine safety, clinical efficacy and immunological mechanism of three subcutaneous injections of three BM32 doses adsorbed to aluminum hydroxide versus aluminum hydroxide (placebo) applied monthly to grass pollen allergic patients (n=70). Primary efficacy endpoint was the difference in total nasal symptom score (TNSS) through grass pollen chamber exposure before treatment and 4weeks after the last injection. Secondary clinical endpoints were total ocular symptom score (TOSS) and allergen-specific skin response evaluated by titrated skin prick testing (SPT) at the same time points. Treatment-related side effects were evaluated as safety endpoints. Changes in allergen-specific antibody, cellular and cytokine responses were measured in patients before and after treatment.

RESULTS

Sixty-eight patients completed the trial. TNSS significantly decreased with mean changes of -1.41 (BM32/20μg) (P=0.03) and -1.34 (BM32/40μg) (P=0.003) whereas mean changes in the BM32/10μg and placebo group were not significant. TOSS and SPT reactions showed a dose-dependent decrease. No systemic immediate type side effects were observed. Only few grade 1 systemic late phase reactions occurred in BM32 treated patients. The number of local injection site reactions was similar in actively and placebo-treated patients. BM32 induced highly significant allergen-specific IgG responses (P<0.0001) but no allergen-specific IgE. Allergen-induced basophil activation was reduced in BM32 treated patients and addition of therapy-induced IgG significantly suppressed T cell activation (P=0.0063).

CONCLUSION

The B cell epitope-based recombinant grass pollen allergy vaccine BM32 is well tolerated and few doses are sufficient to suppress immediate allergic reactions as well as allergen-specific T cell responses via a selective induction of allergen-specific IgG antibodies. (ClinicalTrials.gov number, NCT01445002.).

The improved efficacy of a fixed-dose combination of fluticasone furoate and levocabastine relative to the individual components in the treatment of allergic rhinitis

BACKGROUND

Allergic rhinitis (AR) is a common chronic disease, which has significant detrimental effect on well-being and quality of life as well as substantial socio-economic impact. Combination pharmacotherapy is utilized by 40-50% of patients to treat their symptoms.

OBJECTIVE

To compare the effects of intranasal fluticasone furoate (FF)/levocabastine (LEVO) fixed-dose combination (FDC) with each component alone on allergen-induced nasal and ocular symptoms.

METHODS

A randomized, double-blind, placebo-controlled, three-way, incomplete block, cross-over, proof-of-concept study in 71 patients with AR, evaluated FF 100 μg, LEVO 200 μg and FDC (FF 100/LEVO 200 μg), once daily via intranasal spray for 8 days. On days 1 and 8, total nasal symptom score (TNSS) and total ocular symptom score (TOSS) were assessed every 15 min during a 4-h allergen exposure in the Vienna Challenge Chamber. The primary endpoint was Day 8 weighted mean TNSS.

RESULTS

After 8 days, FDC resulted in both statistically and clinically significant reductions in mean TNSS compared with FF and LEVO alone [adjusted mean differences (95% CI): FDC vs. FF: -2.26 (-2.90, -1.62); FDC vs. LEVO: -2.57 (-3.21, -1.93)]. All active treatments were significantly superior to placebo [adjusted mean difference (95% CI) from placebo: FDC: -4.1 (-4.86, -3.34); FF: -1.84 (-2.66, -1.03); LEVO: -1.53 (-2.34, -0.72)]. Onset of action was rapid following FDC and LEVO treatment with an approximate two unit reduction in mean TNSS from pre-dose levels by 30 min and 1 h. Mean TOSS was also reduced following all active treatments relative to placebo (range 0.6-0.8 unit reduction). All treatments were equally well tolerated.

CONCLUSIONS AND CLINICAL RELEVANCE

These results suggest that once daily FF/LEVO FDC could provide a clinical therapeutic advantage to existing standard monotherapies in the treatment of moderate-to-severe AR, and support progression to evaluation in larger phase III clinical studies.

Randomized phase 1 study of the phosphatidylinositol 3-kinase δ inhibitor idelalisib in patients with allergic rhinitis

BACKGROUND

Phosphatidylinositol 3-kinase p110δ isoform (PI3K p110δ) activity is essential for mast cell activation, suggesting that inhibition of PI3K p110δ might be useful in treating allergic diseases.

OBJECTIVE

We sought to determine the effect of the PI3K p110δ-selective inhibitor idelalisib on allergic responses.

METHODS

This phase 1 randomized, double-blind, placebo-controlled, 2-period crossover study was conducted with the Vienna Challenge Chamber. Grass pollen-induced allergic symptoms were documented during screening. Eligible subjects received idelalisib (100 mg twice daily) or placebo for 7 days, with allergen challenge on day 7. After a 2-week washout period, subjects received the alternate treatment and repeated allergen challenge. Study measures included safety, nasal and nonnasal symptoms, nasal airflow, nasal secretions, basophil activation, and plasma cytokine levels.

RESULTS

Forty-one patients with allergic rhinitis received idelalisib/placebo (n = 21) or placebo/idelalisib (n = 20). Idelalisib treatment was well tolerated. Mean total nasal symptom scores were lower during the combined idelalisib treatment periods compared with placebo (treatment difference [idelalisib - placebo], -1.78; 95% CI, -2.53 to -1.03; P < .001). Statistically significant differences were also observed for the combined treatment periods for total symptom scores, nasal airflow, nasal secretion weight, and nasal congestion scores. The percentage of ex vivo-activated basophils (CD63(+)/CCR3(+) cells; after stimulation with grass pollen) was substantially lower for idelalisib-treated compared with placebo-treated subjects. Plasma CCL17 and CCL22 levels were reduced after idelalisib treatment.

CONCLUSION

Idelalisib treatment was well tolerated in patients with allergic rhinitis and appears to reduce allergic responses clinically and immunologically after an environmental allergen challenge.

Onset and dose-related efficacy of house dust mite sublingual immunotherapy tablets in an environmental exposure chamber

BACKGROUND

The magnitude of effect of sublingual immunotherapy for house dust mite (HDM)-induced allergic rhinitis with or without conjunctivitis is uncertain, partly because there are few well-controlled trials with well-defined doses.

OBJECTIVE

We sought to determine the dose-related efficacy and onset of action of the HDM sublingual immunotherapy tablet MK-8237 (Merck/ALK-Abelló) using the Vienna Challenge Chamber.

METHODS

In this randomized, double-blind, single-site trial, adults with HDM-induced allergic rhinitis with or without conjunctivitis and with or without asthma (n = 124) received 12 developmental units (DU) of MK-8237, 6 DU of MK-8237, or placebo daily for 24 weeks. Subjects underwent 6-hour exposure challenges at screening and weeks 8, 16, and 24. The total nasal symptom score (TNSS) during chamber challenge at week 24 was the primary end point. The TNSS was the sum of 4 nasal symptom scores (maximum = 12). Total ocular symptom scores (TOSSs; 2 symptoms; maximum = 6) and total symptom scores (TSSs; TSS = TNSS plus TOSS; maximum = 18) were secondary end points.

RESULTS

Dose- and time-dependent improvements with MK-8237 versus placebo were observed. At week 24, TNSS improvement relative to placebo was 48.6% (95% CI, 35.3% to 60.2%) with 12 DU of MK-8237 and 26.6% (95% CI, 11.2% to 39.6%) with 6 DU of MK-8237. Statistically significant improvements for TNSSs were also observed at weeks 8 (12 DU of MK-8237) and 16 (6 and 12 DU of MK-8237) and for TOSSs and TSSs by both doses at week 24. MK-8237 was well tolerated. No investigator-assessed anaphylactic allergic reactions or reactions requiring epinephrine were observed.

CONCLUSIONS

MK-8237, 12 DU, reduced nasal and ocular symptoms and exceeded World Allergy Organization-established clinical efficacy criteria (≥20% improvement vs placebo). The onset of action for 12 DU of MK-8237 was week 8. MK-8237, 12 DU, is appropriate for further evaluation to determine the magnitude of effect in an uncontrolled allergen exposure environment.

The CRTH2 antagonist OC000459 reduces nasal and ocular symptoms in allergic subjects exposed to grass pollen, a randomised, placebo-controlled, double-blind trial

BACKGROUND

CRTH2 mediates activation of Th2 cells, eosinophils and basophils in response to prostaglandin D(2). The CRTH2 antagonist OC000459 has previously been demonstrated to reduce airway inflammation and improve lung function in moderate persistent asthma. The objective of the present study was to determine the involvement of CRTH2 in promoting nasal and ocular symptoms in allergic subjects exposed to grass pollen.

METHODS

A single centre, randomised, double-blind, placebo-controlled, two-way crossover study was conducted in 35 male subjects allergic to grass pollen comparing OC000459 200 mg bid with placebo for 8 days. Subjects were exposed to grass pollen (≥ 1400 grains/m(3)) for 6 h on the 2nd and 8th days of treatment and assessed for nasal symptoms, ocular symptoms, other symptoms, nasal secretion weight and rhinomanometry over the 6-h period. After a washout period of 3 weeks, subjects were switched to the alternative treatment for a further 8 days. The trial was registered on the clinical trials.gov database (Identifier NCT01448902).

RESULTS

During the first treatment period, treatment with OC000459 significantly reduced both nasal and ocular symptoms in allergic subjects compared with placebo after challenge with grass pollen. A significant effect was observed on the 2nd day of dosing which was increased on the 8th day of dosing. The therapeutic effects of OC000459 persisted into the second treatment period despite a 3-week washout phase. The safety profile of OC000459 was similar to that of placebo.

CONCLUSION

Treatment with OC000459 was well tolerated and led to a significant and persistent reduction in the symptoms of rhinoconjunctivitis.

Efficacy and safety of ketotifen eye drops as adjunctive therapy to mometasone nasal spray in subjects with seasonal allergic rhinoconjunctivitis

OBJECTIVE

To compare the efficacy and safety of ketotifen 0.025% ophthalmic solution (one drop/eye) with placebo as adjunctive therapy to mometasone nasal spray (50 microg/spray, two puffs/nostril) in subjects with seasonal allergic rhinoconjunctivitis (SARC).

STUDY DESIGN

Single-centre, randomised, double-masked, two-treatment, two-period crossover study.

SETTING

8-hour allergen challenge in the Vienna Challenge Chamber.

STUDY PARTICIPANTS

Subjects were >/=18 years old, had a >/=2-year history of SARC, and were sufficiently responsive to allergen challenge.

INTERVENTIONS

During each challenge, subjects received a single dose of mometasone + ketotifen or mometasone + placebo.

MAIN OUTCOME MEASURES AND RESULTS

47 subjects were randomised, and 44 completed both treatment sequences. Efficacy was based on mean area under the curve (AUC) values for symptom relief scores over time, with the primary variable being the AUC 4-6 hours postdose (AUC(4-6)) for relief of ocular itching. Between-treatment differences were assessed using analysis of variance. While improvement in ocular itching (AUC(4-6)) was observed with both treatments, improvement was significantly (p = 0.014) better with mometasone + ketotifen versus mometasone + placebo, as was improvement based on AUC(0-6) (p = 0.009) and AUC(0-2) (p = 0.006). Similar trends (in favour of mometasone + ketotifen) were observed for improvements in ocular redness, running nose, sneezing and ocular/nasal composite scores (p </= 0.05). None of the safety findings (slit-lamp biomicroscopy, vital signs, adverse events) were clinically significant. One subject discontinued treatment due to mild pharyngitis.

CONCLUSION

Ketotifen eye drops adjunctive to mometasone nasal spray provided greater relief of both ocular and nasal signs and symptoms than mometasone alone in subjects with SARC.

Changes in basophil activation during grass-pollen sublingual immunotherapy do not correlate with clinical efficacy

BACKGROUND

Biomarkers predicting the safety and efficacy of sublingual immunotherapy (SLIT) remain to be established.

METHODS

Eighty-nine patients with allergic rhinoconjunctivitis to grass pollen received either a placebo or five-grass-pollen daily tablet sublingually for 4 months. Following exposure in an allergen challenge chamber, clinical responders and nonresponders were identified individually by evaluating their rhinoconjunctivitis total symptom score (RTSS). Activation of peripheral blood basophils was measured by cytofluorometry before and after 2 or 4 months of immunotherapy, based on CD203c surface expression following allergen stimulation.

RESULTS

Patients receiving the grass-pollen tablet had a relative mean improvement of 29.3% vs placebo in the average RTSS after 4 months of SLIT (P < 0.0003). No significant changes in basophil activation were noticed after 2 or 4 months of SLIT despite induction of specific IgGs. Among individual clinical responders, basophil activation was either decreased, increased, or unmodified during SLIT. Levels of basophil activation prior to immunotherapy were not predictive of local adverse reactions associated with immunotherapy. A moderate association was found between basophil activation and allergen-specific IgE levels, skin reactivity, or RTSS, suggesting that the former is, to some extent, indicative of disease severity. As such, patients with the highest level of basophil activation before treatment were more likely to benefit clinically from SLIT.

CONCLUSIONS

Allergen reactivity of peripheral blood basophils is not a biomarker for adverse events or early onset of clinical responses to SLIT.

Onset of action of loratadine/montelukast in seasonal allergic rhinitis patients exposed to grass pollen

Given the impact of allergic rhinitis (AR) on quality of life, it is important that AR medications have rapid onset of symptom relief. The objective of this study was to determine the onset of action of loratadine (CAS 79794-75-5)/montelukast (CAS 151767-02-1) 10 mg/10 mg (L/M) versus placebo in seasonal AR (SAR) subjects. In this single-center, double-blind, crossover study, subjects with SAR and confirmed sensitivity to grass pollen received single doses of L/M or placebo following exposure to grass pollen in the Vienna Challenge Chamber. Subjects recorded symptoms at 15-min intervals during the first 2 h post dose and at 30-min intervals during the next 2 h. After a 14-day washout, the subjects crossed over to the other treatment. The primary endpoint was onset of action of L/M, defined as the first time point at which the mean change from baseline in total symptom score became and remained significantly different with L/M versus placebo. Secondary endpoints included nasal congestion score and rhinomanometry findings. Onset of action with L/M for total symptom score was 1 h, 45 min (P < 0.01 vs placebo). Significant improvements in subject-assessed nasal congestion scores (P < 0.01) and rhinomanometry (P = 0.036) were noted with L/M as compared with placebo. Overall, L/M was well tolerated. In conclusion, L/M demonstrated rapid onset for broad symptom relief, including nasal congestion, in subjects with SAR.

A placebo-controlled study of the nasal decongestant effect of phenylephrine and pseudoephedrine in the Vienna Challenge Chamber

BACKGROUND

Studies on the efficacy of phenylephrine in the treatment of nasal congestion have yielded inconsistent results, notwithstanding its approval for this indication.

OBJECTIVE

To evaluate and compare the decongestant effect of a single dose of phenylephrine to placebo and pseudoephedrine in patients with seasonal allergic rhinitis.

METHODS

This randomized, placebo-controlled, 3-way crossover study evaluated patient-scored nasal congestion, peak nasal inspiratory flow, and rhinomanometry at more than 6 hours in 39 grass-sensitive patients exposed to grass pollen in the Vienna Challenge Chamber. Patients were dosed with immediate-release formulations of phenylephrine, 12 mg, pseudoephedrine, 60 mg, as a control, or placebo.

RESULTS

Phenylephrine was not significantly different from placebo in the primary end point, mean change in nasal congestion score at more than 6 hours (P = .56), whereas pseudoephedrine was significantly more effective than both placebo (P < .01) and phenylephrine (P = .01). Phase 1 results showed a difference between phenylephrine and placebo that was 64% of the difference between pseudoephedrine and placebo, substantially greater than the 17% difference observed for all phases. Carryover bias due to patient recall of the pseudoephedrine effect may have influenced these results. Rhinomanometry and peak nasal inspiratory flow results were consistent with these data. Neither phenylephrine nor pseudoephedrine had an effect on the nonnasal symptoms. No adverse events were reported in this study.

CONCLUSIONS

During a 6-hour observation period, a single dose of pseudoephedrine but not phenylephrine resulted in significant improvement in measures of nasal congestion. Neither phenylephrine nor pseudoephedrine had an effect on nonnasal symptoms.

Fluticasone furoate versus placebo in symptoms of grass-pollen allergic rhinitis induced by exposure in the Vienna Challenge Chamber

OBJECTIVE

The Vienna Challenge Chamber (VCC) offers a controlled and controllable paradigm in which to reproducibly evaluate the efficacy of anti-allergic treatment. The aim of this study was to assess the efficacy of the novel intranasal corticosteroid fluticasone furoate (FF) in the VCC.

METHODS

The single-centre, randomised, double-blind, placebo-controlled, two-period crossover study was conducted in 59 adult males with grass pollen allergic rhinitis (AR). Patients received either Fluticasone furoate 200 mcg once-daily, or placebo intranasally for 8 days. AR symptoms were induced during 4-hour allergen challenges with grass pollen in the VCC at the end of each 8-day treatment period. A first challenge was conducted at 1-5 hours post-dose, followed by a second challenge at 22-26 hours post-dose. The primary endpoint was total nasal symptom score (TNSS; sum of itch, sneeze, rhinorrhoea, obstruction symptoms assessed on a categorical scale of 0-3) weighted mean over 2-5 hours post-dose. Secondary endpoints included: TNSS weighted mean over 23-26 hours post-dose and global symptom score, eye symptom score, nasal secretions and nasal airflow weighted means over 2-5 and 23-26 hours post-dose.

RESULTS

Fluticasone furoate showed consistent attenuation of AR symptoms in both the early and late challenges. Compared with placebo, weighted mean of TNSS was reduced on average by 4.14 point-scores at 2-5 hours post-dose and 3.63 point scores at 23-26 hours post-dose. These positive effects were also seen across all secondary endpoints.

CONCLUSION

An 8-day treatment course of intranasal FF 200 mcg given once-daily statistically significantly reduced symptoms of AR including associated eye symptoms. Statistical significance was declared where the relevant two-sided 95% confidence interval did not contain zero. This positive effect was sustained over 24 hours suggesting that fluticasone furoate could be efficacious as a once daily steroid.

Effects of rupatadine vs placebo on allergen-induced symptoms in patients exposed to aeroallergens in the Vienna Challenge Chamber

BACKGROUND

Rupatadine is a novel compound with potent dual antihistamine and platelet-activating factor antagonist activities and no sedative effects.

OBJECTIVE

To evaluate the efficacy of rupatadine, 10 mg once daily, and placebo on allergen-induced symptoms (including nasal congestion), nasal airflow, nasal secretion, and subjective tolerability in response to grass pollen in a controlled allergen-exposure chamber.

METHODS

In a randomized, double-blind, placebo-controlled, crossover trial, 45 patients with a history of seasonal allergic rhinitis received rupatadine or placebo every morning for 8 days in 2 different periods separated by a 14-day washout interval. On day 8 of each crossover period, patients underwent a 6-hour allergen exposure in the Vienna Challenge Chamber, where a constant and homogeneous concentration of aeroallergens was maintained. Subjective and objective assessments were performed online during the exposure.

RESULTS

Subjective single and composite nasal and nonnasal symptoms were consistently less severe with rupatadine use than with placebo use starting from the first evaluation at 15 minutes to the end of the 6-hour Vienna Challenge Chamber challenge, with the most significant effects seen for nasal rhinorrhea, nasal itching, sneezing attacks, and total nasal symptoms (P < .001 for all). All the other symptoms (including nasal congestion, P < or = .005) were also significantly reduced with active treatment compared with placebo use. Mean secretion weights and overall feeling of complaint were significantly lower with rupatadine therapy than with placebo use (P < or = .001). Overall, rupatadine treatment was well tolerated.

CONCLUSION

Rupatadine treatment is effective and well tolerated in patients with allergen-induced symptoms exposed to aeroallergens in a controlled exposure chamber.

Azelastine nasal spray and desloratadine tablets in pollen-induced seasonal allergic rhinitis: a pharmacodynamic study of onset of action and efficacy

OBJECTIVE

To assess the efficacy and onset of action of azelastine nasal spray and desloratadine tablets in patients with allergen-induced seasonal allergic rhinitis (SAR).

RESEARCH DESIGN AND METHODS

46 adult patients with a history of SAR were exposed to a controlled grass pollen concentration for 6 h in the Vienna Challenge Chamber (VCC) in each treatment period according to a randomised, double-blind (double-dummy), three-period, three-sequence crossover design (wash-out period of 12 days). Single doses of study medication (one puff nasal spray into each nostril of azelastine, 0.2 mg, or placebo before swallowing one encapsulated tablet of desloratadine, 5 mg) were administered 2 h after the start of the allergen challenge. Results of subjective and objective assessments were recorded throughout the challenge.

RESULTS

Efficacy of azelastine nasal spray was significantly superior compared to desloratadine tablets (p = 0.005) and placebo (p < 0.001). Desloratadine was significantly better than placebo (p < 0.001). Decrease both in Major Nasal Symptom Score (MNSS) and in Total Nasal Symptom Score (TNSS) was fastest after azelastine treatment. Improvement of nasal symptom severity was most pronounced after azelastine treatment for all nasal symptoms including nasal congestion. Onset of action was 15 min for azelastine compared to 150 min for desloratadine. Both active preparations were safe and well tolerated.

CONCLUSIONS

This study confirms the usefulness of azelastine nasal spray for the symptomatic treatment of seasonal allergic rhinitis. Concerning onset of action in particular, the results favour the topical treatment over systemic therapy.

Levocetirizine has a longer duration of action on improving total nasal symptoms score than fexofenadine after single administration

AIMS

To compare the onset and duration of action of the new antihistamine levocetirizine with that of the second-generation antihistamine fexofenadine using the Vienna Challenge Chamber (VCC). The latter is an environment where subjects can be exposed to specific aeroallergens in controlled and reproducible conditions allowing for precise comparisons of anti-allergic drugs.

METHODS

Ninety-four subjects received a single dose of levocetirizine 5 mg, fexofenadine 120 mg or placebo in a random order using a three-way cross-over design. On day 1, subjects were exposed to grass pollens (1500 grains/m(3)) in the VCC over a period of 4 h. Treatment was given 2 h after the start of challenge. On day 2, 22 h after drug intake, subjects were again exposed to pollens for 6 h. Specified symptoms were assessed by the subjects every 15 min using 5-point scales. The main efficacy parameter was the change from baseline in the Major Symptom Complex Score (MSCS = sum of rhinorrhea, sneezing, itchy nose and eyes).

RESULTS

Baseline characteristics, including symptoms scores, were similar in the three study groups. During the first 2 h after drug intake both antihistamines achieved clinically relevant and significant (P < 0.001) improvements in symptom scores. Twenty-two to 24 h after drug intake, mean (SEM) MSCS reductions were: 1.9 (0.3) after placebo (baseline of 9.7), 3.8 (0.3) after fexofenadine (baseline of 9.9), and 5.1 (0.3) after levocetirizine (baseline of 9.8). Levocetirizine was significantly (P < 0.001) more effective than fexofenadine with a score difference of 1.3 (95% CI 0.7, 1.9). This was maintained until the end of the study (up to 28 h).

CONCLUSIONS

A rapid onset of action in alleviating seasonal allergic rhinitis (SAR) symptoms of subjects exposed to grass pollens in the VCC was observed after levocetirizine and fexofenadine. Levocetirizine was more effective than fexofenadine at and later than 22 h after drug intake, an indication of the longer-duration of action of levocetirizine.

Clinical study of the therapeutic efficacy and safety of emedastine difumarate versus cetirizine in the treatment of seasonal allergic rhinitis

OBJECTIVE

The therapeutic efficacy and tolerability of emedastine difumarate (CAS 87233-62-3) in male and female Caucasian patients with seasonal allergic rhinitis as compared to cetirizine (CAS 83881-51-0) was evaluated.

METHODS

The study was designed as a double-blind, randomised, parallel groups comparison of two antihistamines administered by oral route (emedastine 4 mg o.d. versus cetirizine 10 mg o.d.) in a population of 120 patients suffering from grass pollen allergic rhinitis. The duration of the treatment period was 14 days. Primary efficacy variable was a total symptoms score (including among symptoms nasal congestion, sneezing, rhinorrhea, nasal/throat/palate itching, eye itching and lacrimation) evaluated after 14 days of treatment vs. baseline value. Safety was assessed on routine laboratory assays and recording vital signs and adverse events (AEs).

RESULTS

The between-group difference in primary efficacy variable averaged over the 2-week treatment period was not statistically significant. Results clearly showed that no significant difference exists between the two treatments as far as total symptoms score evaluated after 14 days of treatment vs. baseline values are concerned. Therefore, the efficacy profiles of the study medications are overlapping. The pattern and incidence of AEs was similar in both treatment groups. The most frequent AEs with both compounds were related to the CNS, headache being the most reported one. In particular, this study seems to disclose a slighter tendency to drowsiness with emedastine than with cetirizine.

CONCLUSIONS

Both drugs under investigation in this trial appear to be effective for relieving the symptoms of seasonal allergic rhinitis in Caucasian adult patients. The results demonstrate that emedastine 4 mg o.d. is comparable in efficacy to cetirizine 10 mg once daily in the symptomatic management of seasonal allergic rhinitis. Moreover, based on the results of this study, emedastine can be considered a safe and well-tolerated drug and its safety profile seems to resemble that of cetirizine.

A direct comparison of the efficacy of antihistamines in SAR and PAR: randomised, placebo-controlled studies with levocetirizine and loratadine using an environmental exposure unit - the Vienna Challenge Chamber (VCC)

OBJECTIVE

The Vienna Challenge Chamber (VCC) is an established method for the controlled exposure of patients to specific allergens, used to make valid comparisons between antihistamines. The aim of the significantly more than loratadine at all time two placebo-controlled, randomised studies reported here was to compare the efficacy and safety of levocetirizine 5 mg od and loratadine 10 mg od in subjects suffering from seasonal allergic rhinitis (SAR) or perennial allergic rhinitis (PAR).

SUBJECTS AND METHODS

During each study period, SAR and PAR subjects were exposed to grass pollen or house-dust mite allergens, respectively for 6 h on 2 consecutive days in the VCC. Each day, medications were administered 2 h after the start of the challenge; with a washout of at least 5 days between each period. The main criterion for evaluation of efficacy was the major symptom complex (MSC) for SAR and the complex symptom score (CSS) for PAR.

RESULTS

The pattern of patients' response was similar in SAR and PAR. Both levocetirizine and loratadine were superior to placebo in alleviating SAR and PAR symptoms at all time intervals evaluated during the two study days. Levocetirizine decreased the mean MSC score intervals in SAR subjects, with the most marked difference observed on day 2 (p = 0.002). In PAR patients, although with borderline significance (p = 0.08), levocetirizine decreased the mean CSS more than loratadine. Levocetirizine appeared to have a faster onset of action than loratadine in SAR (45 min versus 1 h 15 min) and PAR (1 h versus 1 h 30 min). However, these apparent differences were not tested for statistical significance. Both medications were well tolerated and no treatment-related adverse events were reported. This level of antihistamine efficacy was maintained regardless of whether the subjects' rhinitis was seasonal or perennial.

CONCLUSION

This study demonstrated that levocetirizine is superior to loratadine in improving symptoms in SAR and that there is a similar trend in PAR.

Onset and Duration of Action of Ketotifen???0.025%???and???Emedastine???0.05% in Seasonal Allergic Conjunctivitis

OBJECTIVE

To compare the efficacy, onset and duration of action, and the safety of ketotifen fumarate 0.025% ophthalmic solution and emedastine difumarate 0.05% ophthalmic solution in subjects with seasonal allergic conjunctivitis (SAC) induced by allergen exposure, using the Vienna Challenge Chamber model.

DESIGN AND SETTING

This was a double-masked, randomised, comparative, crossover study conducted at an allergy outpatient clinic in Austria.

STUDY PARTICIPANTS

Subjects with an allergy to grass pollen were exposed to the allergen in a pollen chamber for 4 hours, followed by a 3-hour break and then a second exposure for 3 hours.

INTERVENTIONS

Study participants were randomised to a treatment sequence (ketotifen followed by emedastine or emedastine followed by ketotifen), receiving 1 drop per eye of ketotifen or emedastine 2 hours after the initial allergen exposure in the pollen chamber.

OUTCOMES

Individual and composite ocular, individual and composite nasal, and total (ocular + nasal) symptom complex scores were determined by repeated exposure to allergen 0-2 hours and 5-8 hours after dosing. Onset of action was defined as the time to the first observation of a 20% reduction from baseline in the composite ocular symptom score.

RESULTS

All 37 subjects enrolled completed the study. The median time to onset of action was 15 minutes for ketotifen and 30 minutes for emedastine. This difference was significant using the generalised linear model (p = 0.048), but not for the log-rank test analysis. In the initial 2 hours post dose, ketotifen provided significantly greater relief of both composite ocular symptoms (p = 0.026) and total symptom complex (p = 0.014). Both medications were effective in reducing symptoms 5 to 8 hours after dosing. No adverse events were reported for either treatment.

CONCLUSIONS

In the Vienna Challenge Chamber model, ketotifen and emedastine both effectively alleviated ocular symptoms of SAC after single-dose administration. Ketotifen had a faster onset of action and provided better symptom relief than emedastine during the first 2 hours after dosing. The rapid onset of action and symptom control make ketotifen a valuable treatment for SAC.

Controlled comparison of the efficacy and safety of cetirizine 10 mg o.d. and fexofenadine 120 mg o.d. in reducing symptoms of seasonal allergic rhinitis

BACKGROUND

The efficacy, onset and duration of action and safety of cetirizine 10 mg o.d., fexofenadine 120 mg o.d., and placebo were compared in this investigator-blinded, crossover study involving the use of the Vienna Challenge Chamber.

METHODS

40 volunteers with seasonal allergic rhinitis were exposed to a controlled grass pollen concentration for 6 h on 2 consecutive days. Subjective symptoms and objective measurements were recorded during the allergen exposure periods.

RESULTS

Both active medications were significantly more effective than placebo and had a comparable onset of action in alleviating the symptoms of seasonal allergic rhinitis. The efficacy of both active drugs was comparable for the first 4 h after administration of the drugs on day 1 and day 2. However from 22 to 24 h after the first dose cetirizine was significantly superior to fexofenadine for the major symptom complex score and for sneezing. Concerning the total symptom complex score at day 2 fexofenadine could not reach superiority to placebo. No serious adverse events were reported.

CONCLUSIONS

Cetirizine and fexofenadine were significantly better than placebo, also in reducing the symptom of nasal congestion. However cetirizine appears to have a longer duration of action than fexofenadine.