Safety and tolerability of fexofenadine for the treatment of allergic rhinitis in children 2 to 5 years old

Biowaiver Monograph for Immediate-Release Solid Oral Dosage Forms: Fexofenadine

In this monograph, the potential use of methods based on the Biopharmaceutics Classification System (BCS) framework to evaluate the bioequivalence of solid immediate-release (IR) oral dosage forms containing fexofenadine hydrochloride as a substitute for a pharmacokinetic study in human volunteers is investigated. We assessed the solubility, permeability, dissolution, pharmacokinetics, pharmacodynamics, therapeutic index, bioavailability, drug-excipient interaction, and other properties using BCS recommendations from the ICH, FDA and EMA. The findings unequivocally support fexofenadine's classification to BCS Class IV as it is neither highly soluble nor highly permeable. Further impeding the approval of generic equivalents through the BCS-biowaiver pathway is the reference product's inability to release ≥ 85 % of the drug substance within 30 min in pH 1.2 and pH 4.5 media. According to ICH rules, BCS class IV drugs do not qualify for waiving clinical bioequivalence studies based on the BCS, even though fexofenadine has behaved more like a BCS class I/III than a class IV molecule in pharmacokinetic studies to date and has a wide therapeutic index.

Bioequivalence of 2 Pediatric Formulations of Fexofenadine Hydrochloride Oral Suspension

Fexofenadine hydrochloride (HCl) is a second-generation, nonsedating, histamine H1-receptor antagonist used to manage seasonal allergic rhinitis and chronic idiopathic urticaria. A new oral pediatric suspension of fexofenadine HCl has been developed, with the preservative potassium sorbate replacing parabens. The objective of this phase 1 single-center, open-label, randomized, 2-treatment, full-replicated, 4-period, 2-sequence crossover study in healthy adult volunteers was to assess the bioequivalence of 30 mg of the new oral suspension of fexofenadine HCl (test) versus 30 mg of the marketed pediatric oral suspension of fexofenadine HCl (reference). The replicate design was based on the high intra-individual variability of fexofenadine (>30% on Cmax ). The study comprised 68 randomized and treated volunteers. Plasma concentrations of fexofenadine were similar following the administration of a single dose of each formulation. Cmax , AUClast , AUC, median tmax , and mean t1/2z were similar between administrations of the same fexofenadine formulation and between formulations. A high intra-individual variability was confirmed with both formulations. Bioequivalence of the test and reference fexofenadine HCl formulations was demonstrated as the 90% confidence intervals of the geometric least squares mean ratio for Cmax , AUClast , and AUC of fexofenadine were all within the bioequivalence range of 0.80-1.25. There were no serious adverse events (AEs) or study discontinuations due to treatment-emergent AEs with either fexofenadine HCl formulation. The new paraben-free fexofenadine HCl 30-mg oral suspension and marketed fexofenadine HCl 30-mg pediatric oral suspension are bioequivalent under fasting conditions, with no safety concerns and a safety profile consistent with the known profile of fexofenadine.

Insights into urticaria in pediatric and adult populations and its management with fexofenadine hydrochloride

OBJECTIVE

The present narrative review provides a comprehensive update of the current knowledge on urticaria, both in adult and pediatric populations, and on the safety and efficacy of fexofenadine hydrochloride (HCl) as a treatment option.

DATA SOURCE

A literature search was conducted on Embase and Medline.

STUDY SELECTION

Clinical studies published in English and published between 1999 and 2020 were selected.

RESULTS

Although the exact pathogenesis of urticaria is not fully understood, multiple pathways of mast cell activation are discussed to explain the existence of phenotypically different clinical manifestations of urticaria. An overview of the worldwide prevalence of chronic urticaria, including disease burden and patient's quality of life is provided. The impact of urticaria on patient's life differs on the basis of whether its form is acute or chronic, but pharmacological approaches are most often needed to control the disabling symptoms. A summary of the current management of urticaria recommended by different guidelines across countries (Global; European; American; Australian; Asian; Japanese) is presented. Non-sedating, second-generation H₁-antihistamines are the preferred choice of treatment across several guidelines worldwide. Herein, the efficacy and safety of fexofenadine HCl, a representative second-generation H₁-antihistamine approved for the treatment of urticaria, is discussed. The occurrence of urticaria manifestations in COVID-19 patients is also briefly presented.

CONCLUSION

The burden of acute and chronic urticaria is high for patients. Second generation anti-histamines such as fexofenadine HCl can help managing the symptoms.

Fexofenadine: review of safety, efficacy and unmet needs in children with allergic rhinitis

Allergic rhinitis (AR) is the most common undiagnosed chronic condition in children. Moderate/severe AR symptoms significantly impair quality of life, and cause sleep disruption, absenteeism and decreased productivity. Additionally, untreated AR predisposes children to asthma and other chronic conditions. Although intranasal corticosteroids are the most effective pharmacologic treatment for AR, oral antihistamines are often preferred. First-generation antihistamines may be chosen to relieve AR symptoms as they are inexpensive and widely available; however, they cause sedative and cardiovascular negative effects due to poor receptor selectivity. Therefore, second-generation antihistamines were developed to reduce adverse effects while retaining efficacy. There are fewer clinical trials in children than adults, therefore, efficacy and safety data is limited, particularly in children under 6 years, highlighting the need to generate these data in young children with AR. Fexofenadine, a highly selective second-generation antihistamine, effectively alleviates symptoms of AR, is non-sedating due to decreased blood-brain barrier permeability, and is devoid of cardiovascular side effects. Importantly, fexofenadine relieves the ocular symptoms of allergic conjunctivitis, which occur concomitantly with AR, improving quality of life. Overall, fexofenadine displays a favorable safety profile and results in greater treatment satisfaction in children compared with other second-generation antihistamines. This review aimed to evaluate and compare the safety and efficacy of fexofenadine with other available first- and second-generation antihistamines in children with AR.

Newer-generation antihistamines and the risk of adverse events in children: A systematic review

BACKGROUND

H1-antihistamines (AHs) are widely used for the treatment of allergic diseases, being one of the most commonly prescribed classes of medications in pediatrics. Newer-generation AHs are associated with fewer adverse effects compared with first-generation AHs. However, their relative harms in the pediatric population still need scrutiny.

METHODS

We performed a systematic review of randomized controlled trials (RCTs), which included comparisons of safety parameters between an orally administered newer-generation AH and another AH (first- or second-generation), montelukast, or placebo in children aged ≤12 years. We searched MEDLINE and CENTRAL, independently extracted data on study population, interventions, adverse events (AEs), and treatment discontinuations, and assessed the methodologic quality of the included RCTs using the Cochrane's risk of bias tool.

RESULTS

Forty-five RCTs published between 1989 and 2017 met eligibility criteria. The majority of RCTs included school-aged children with allergic rhinitis and had a follow-up period of up to a month. Four RCTs reported serious AEs in patients receiving a newer-generation AH, but only two patients experienced a possibly drug-related serious AE. The occurrence of AEs, drug-related AEs, and treatment discontinuations due to AEs varied between RCTs. Most AEs reported were of mild intensity. Indirect evidence indicates that cetirizine is more sedating than the other newer-generation AHs.

CONCLUSION

Our findings confirm that newer-generation AHs have a favorable safety and tolerability profile. However, we could not draw firm conclusions regarding the comparative safety profile of the newer-generation AHs due to the paucity of head-to-head RCTs, variation in definitions and reporting of AEs, and short follow-up duration.

The clinical evidence of second-generation H1-antihistamines in the treatment of allergic rhinitis and urticaria in children over 2 years with a special focus on rupatadine

INTRODUCTION

Many obstacles limit the development of pharmacologic studies in children, in particular ethical and practical issues. Therefore, although second-generation H1-antihistamines (sgAH) are recommended by international guidelines as first-line therapy in childhood allergies, most data on the efficacy of antihistamines in children has been extrapolated from studies in adult patients.

AREAS COVERED

The current review focuses on rupatadine, a well-studied modern sgAH that has dual affinity for histamine H1-receptors and PAF receptors. In recent years, clinical efficacy and safety controlled-clinical trials on rupatadine were conducted in children and were based on latest current guidelines using validated tools of allergic rhinitis and urticaria.

EXPERT OPINION

Children are not little adults since they present specific physiologic, metabolic, and developmental differences that should be evaluated in specific trials. The clinical evidence with rupatadine in children is the most recent and validated in accordance with current recommendations, with extensive direct data on efficacy and safety in pediatric populations over 2 years old.

Antihistamine effects and safety of fexofenadine: a systematic review and Meta-analysis of randomized controlled trials

Background

As a new generation antihistamine, fexofenadine has been widely used in allergic diseases. However, there is still a lack of collective evidence regarding the antihistamine effects and safety profiles of fexofenadine relative to other antihistamine drugs and placebo. Therefore, we aimed to systematically evaluate the antihistamine effects and safety of fexofenadine.

Methods

An electronic literature search of randomized controlled trials (RCTs) was performed using Embase, Cochrane and PubMed from establishment to January 1st, 2018. RCTs comparing the antihistamine effects or safety (adverse events, sedative effects, and cognitive/psychomotor function) of fexofenadine with either other antihistamines or placebo for healthy subjects and patients with allergy were selected.

Results

Fifty-one studies of 14,551 participants met the inclusion criteria. When compared with the first-generation antihistamines, fexofenadine produced significantly lower adverse events frequency (OR = 0.446; 95% CI: 0.214 to 0.929, P = 0.031), significantly lower sedative effects frequency (OR = 0.265; 95% CI: 0.072 to 0.976, P = 0.046) and significantly less change of all cognitive/psychomotor function. When compared with the second-generation antihistamines, fexofenadine produced significantly marginal sedative effects (OR = 0.59; 95% CI, 0.38 to 0.93; P = 0.02) and significantly less change of most of the cognitive/psychomotor function. When compared with placebo, fexofenadine produced more significant antihistamine effects.

Conclusions

Fexofenadine has a positive antihistamine effect, which is probably no worse than the second-generation antihistamines. Fexofenadine probably has a favorable safety profile, which is more likely better than that of the first-generation antihistamines. There is lack of data to support that fexofenadine has a better overall safety profile compared to the second-generation antihistamines, however, some presently available evidence on sedative effects and certain aspects of cognitive/psychomotor function favors fexofenadine. Therefore, fexofenadine may be worthy of recommendation for safety related workers.

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.

Evaluation of treatment satisfaction in children with allergic disease treated with an antihistamine: an international, non-interventional, retrospective study

BACKGROUND AND OBJECTIVES

Histamine H(1)-receptor antagonists (antihistamines) have been shown to be efficacious and safe in children and are recommended as first-line treatment for the symptoms of allergic rhinitis and urticaria. No published study to date has directly compared satisfaction with the different antihistamines in children in a real-life clinical setting. This study aimed to investigate parent and physician satisfaction with the efficacy and tolerability of oral antihistamine treatment in children and to compare satisfaction between levocetirizine and the other antihistamines used by children in this cohort.

METHODS

This was an international Observational Survey in Children with Allergic Rhinitis (OSCAR). Children aged 2-12 years, with a history of an allergic condition leading to a consultation, were enrolled from 424 primary-care/specialist allergy clinics across Bulgaria, India, Portugal, Romania, Russia, South Korea and Spain. At the consultation, parents and physicians of eligible children completed questionnaires evaluating their satisfaction with specific antihistamines currently employed for management of the child's allergic condition, as well as their intention for future use of that treatment. Parents' satisfaction scores for efficacy, tolerability and global satisfaction with the antihistamine used were primary study outcomes, while physicians' satisfaction scores for the same measures were secondary outcomes. Other secondary outcomes were parents' rating of the impact of the antihistamine treatment on their child's sleep and school performance, and parents' and physicians' willingness to use/recommend the same antihistamine in the future.

RESULTS

A total of 4581 patients were enrolled; 3048 (66.5%) had allergic rhinitis (55.9% persistent allergic rhinitis and 44.1% intermittent allergic rhinitis), and 663 (14.5%) had urticaria as primary conditions. Additionally, 2465 patients (53.8%) suffered from other allergic diseases, including allergic asthma (33.3%), atopic dermatitis (17.6%), food allergy (5.3%), other allergies (5.0%) and drug hypersensitivity (2.0%). Parents' and physicians' satisfaction scores were closely concordant and demonstrated significantly greater global satisfaction for the second-generation antihistamines than for the first-generation antihistamines. Levocetirizine (n = 2339) and fexofenadine (n = 42) generally scored highest for efficacy, tolerability and global satisfaction, as well as for impact on the child's ability to function at school, quality of school activities and quality of sleep. Furthermore, >97% of parents and physicians indicated their desire to continue or recommend the use of levocetirizine in the future. Somnolence, the most commonly reported adverse event in this survey, was observed predominantly in patients treated with first-generation antihistamines. Among second-generation antihistamines, reports of somnolence were most frequent in the cetirizine group.

CONCLUSION

Second-generation antihistamines have a better risk:benefit ratio than first-generation antihistamines, indicating that the latter should be avoided or their use limited in children whenever possible. Levocetirizine and fexofenadine were perceived by parents and physicians to produce significantly higher treatment satisfaction than the majority of the other antihistamines with respect to overall efficacy and tolerability, and impact on the child's sleep and school activities. The newer antihistamine levocetirizine seems to be a preferred and appropriate future treatment choice for children with allergic diseases.

Fexofenadine: biochemical, pharmacokinetic and pharmacodynamic properties and its unique role in allergic disorders

BACKGROUND

Fexofenadine is one of several second-generation H(1)-antihistamines approved for the treatment of various allergic disorders; however, it shows numerous unique properties that make it an optimal choice for many patients.

OBJECTIVE

To review the pharmacology, efficacy and safety of fexofenadine and the attributes differentiating it from other H(1)-antihistamines.

METHODS

We performed a literature search in PubMed/MEDLINE (1966 - March 2009) using the keywords fexofenadine, antihistamine, allergic rhinitis and chronic urticaria. We also reviewed data provided by the manufacturer in addition to reports from various governmental agencies.

RESULTS/CONCLUSIONS

Fexofenadine is devoid of sedative and anticholinergic effects and may offer equivalent or greater efficacy in treating allergic disorders compared with other currently available second-generation H(1)-antihistamines. In addition, fexofenadine may offer cost savings over other selected H(1)-antihistamines owing to its recent availability in generic form in the US.

Update on prescription and over-the-counter histamine inverse agonists in rhinitis therapy

Allergic rhinitis (AR) is associated with histamine-mediated physiologic events. The currently used histamine antagonists are all inverse agonists that bind and inactivate histamine H1 receptors. Second-generation antihistamines are much more H1-receptor selective with less central nervous system penetration than first-generation agents. Antihistamines typically are more effective in seasonal than perennial AR and do not demonstrate significant relief of nasal congestion. The recent availability of some second-generation antihistamines as over-the-counter products clearly places them as the preferred first-line treatment for mild to moderate AR based on safety when compared with first-generation over-the-counter antihistamines. The remaining prescription-only second-generation antihistamines, fexofenadine, desloratadine, and levocetirizine, all have unique attributes. Antihistamines in oral, intranasal, or intraocular formulations will likely remain among the mainstays of allergy therapeutics.

New oral H1 antihistamines in children: facts and unmeet needs

BACKGROUND

Second-generation antihistamines differ from first-generation ones because of their elevated specificity and affinity for peripheral H1-receptors and because of their lower penetration to the central nervous system, having fewer sedative effects as a result. Over the last few years, new compounds with different pharmacokinetic properties have been synthesized. More recent improvements of the molecules, generally in the form of active metabolites, led to the synthesis of new-generation antihistamines.

METHODS

Recommendations on the minimum criteria that would have to be met for compounds to be classified as new-generation antihistamines have been recently established by a consensus statement. In the past, the pharmacokinetics and pharmacodynamics of H1 antihistamines have not been optimally investigated in the pediatric population, especially in infants and young children.

RESULTS

The pharmacology of second-generation H1 antihistamines has been investigated relatively deeper than old antihistamines in children. In the pediatric population, clinical studies with new-generation antihistamines are still limited in number and, with rare exceptions, of brief duration. Comparative trials on the efficacy and safety between different compounds are also lacking.

CONCLUSIONS

Properly designed, long-term trials with new-generation H1 antihistamines need to be performed in single age groups, in order to better define the effects of these drugs in all pediatric population.

Fexofenadine hydrochloride in the treatment of allergic disease: a review

Fexofenadine is a selective, non-sedating H1 receptor antagonist, marketed in the United States since 2000. The FDA approved an oral suspension in 2006, for the treatment of seasonal allergic rhinitis and chronic idiopathic urticaria in children. The tablet, capsule, and oral suspension are bioequivalent. Although fexofenadine does not use P450 CYP 3A4 it does interact with a number of drugs at P-glycoprotein and organic anion transporter polypeptides. The risk of toxicity from other drugs may increase with the administration of fexofenadine. Orange and grapefruit juices reduce the bioavailability of fexofenadine. Fexofenadine has been shown to have an impact on inflammatory mediators, other than histamine, such as decreasing the production of LTC₄, LTD₄, LTE₄, PGE₂, and PGF_2α; inhibiting cyclo-oxygenase 2, thromboxane; limiting iNOS generation of NO; decreasing cytokine levels (ICAM-1, ELAM-1, VCAM-1, RANTES, I-TAC, MDC, TARC, MMP-2, MMP-9, tryptase); and diminishing eosinophil adherence, chemotaxis, and opsonization of particles. These effects may provide benefit to some of the inflammatory responses of an acute allergic reaction and provide a basis for future development of H1 antagonists with stronger anti-inflammatory effects. These studies also support the contention that fexofenadine is effective for the treatment of allergic rhinits and chronic idiopathic urticaria.

Anti-histamines for prolonged non-specific cough in children

BACKGROUND

Non-specific cough is defined as non-productive cough in the absence of identifiable respiratory disease or known aetiology. It is commonly seen in paediatric practice. These children are treated with a variety of therapies including anti-histamines. Also, anti-histamines are advocated as an empirical treatment in adults with chronic cough.

OBJECTIVES

To evaluate the effectiveness of anti-histamines in treating children with prolonged non-specific cough.

SEARCH STRATEGY

We searched the Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, OLDMEDLINE and EMBASE databases. The latest searches were performed in November 2007.

SELECTION CRITERIA

All randomised controlled trials comparing anti-histamines with a placebo or placebo-like medication with cough as an outcome, where cough is not primarily related to an underlying respiratory disorder such as cystic fibrosis, asthma, or suppurative lung disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study quality and extracted data.

MAIN RESULTS

Three included therapeutic studies had 182 randomised participants with 162 completing the trials although in one study, children with recurrent wheeze were also included. The two included safety evaluation studies randomised 963 participants with 793 completing the trials. Clinical heterogeneity was evident and limited data prevented combining data for meta-analysis. The two larger therapeutic studies described significant improvement in both the intervention and the placebo/placebo-like arms with no significant difference between the two groups. In the study with the smallest sample size, cetirizine (a second generation anti-histamine) was significantly more efficacious than placebo in reducing chronic cough in children associated with seasonal allergic rhinitis, and the effect was seen within two weeks of therapy. Combined data from the safety evaluation studies revealed a non-significant difference between groups (OR 1.6, 95% CI 0.7 to 3.82) for cough as an adverse event but the trend favoured the placebo arm.

AUTHORS' CONCLUSIONS

This review has significant limitations. However, our finding of uncertain efficacy of anti-histamines for chronic cough are similar to that for acute cough in children. In contrast to recommendations in adults with chronic cough, anti-histamines cannot be recommended as empirical therapy for children with chronic cough. If anti-histamines were to be trialled in these children, current data suggest a clinical response (time to response) occurs within two weeks of therapy. However the use of anti-histamines in children with non-specific cough has to be balanced against the well known risk of adverse events especially in very young children.