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.

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.

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.

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.

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.

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.

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.