CLINICAL TRIALS PROFILE FOR CLARINEX D 24 HOUR

All Clinical Trials for CLARINEX D 24 HOUR

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00636870 ↗	Fexofenadine (Allegra®) in Healthy Adults Who Have Been Identified as Slow Metabolizers for Desloratadine	Completed	Sanofi	Phase 4	2003-02-01	To evaluate the single-dose and steady-state pharmacokinetics of desloratadine and fexofenadine in desloratadine slow metabolizers. To evaluate the safety and tolerability of desloratadine compared to fexofenadine following single and multiple oral doses administered to desloratadine slow metabolizers.
NCT00637585 ↗	Fexofenadine HCl 180 mg, Desloratadine 5 mg and Placebo in Suppression of Wheal and Flare Induced by Histamine	Completed	Sanofi	Phase 4	2002-12-01	To examine the relative potency, onset of action and duration of action of fexofenadine HCl 180 mg (ALLEGRA) and desloratadine 5 mg (CLARINEX) as compared to placebo on skin wheals and flares induced by histamine.
NCT00757562 ↗	Safety of Desloratadine in Children With Allergy Sensitivity and Chronic Hives, Who Are Poor Metabolizers of Desloratadine (Study P02994)	Completed	Merck Sharp & Dohme Corp.	Phase 3	2002-11-01	This study was conducted to evaluate the safety and tolerance of desloratadine after 5 weeks of repetitive dosing in children ages 2 to 12 years old with allergic hypersensitivity or chronic hives. All of the subjects enrolled in this trial were previously identified in an earlier trial to be poor metabolizers of desloratadine.
NCT00783133 ↗	Preference for Clarinex Tablets vs. Allegra Tablets in Patients With Seasonal Allergies (Study P03177)	Completed	Merck Sharp & Dohme Corp.	Phase 4	2002-11-01	This was a crossover study designed to see if patients with seasonal allergy symptoms preferred Clarinex® or Allegra®. Patients were randomized to take 7 days of Clarinex or Allegra treatment, followed by a 5 to 28-day washout period (days when no drug is given), followed by 7 days of the opposite treatment. At the end of each 7-day treatment, patients were asked questions to determine which drug, Clarinex or Allegra, the patient prefers more.
NCT00794248 ↗	Preference for Clarinex Tablets vs. Allegra Tablets in Patients With Seasonal Allergies (Study P03179)	Completed	Merck Sharp & Dohme Corp.	Phase 4	2002-11-01	This was a crossover study designed to see if patients with seasonal allergy symptoms preferred Clarinex® or Allegra®. Patients were randomized to take 7 days of Clarinex or Allegra treatment, followed by a 5 to 28-day washout period (days when no drug is given), followed by 7 days of the opposite treatment. At the end of each 7-day treatment, patients were asked questions to determine which drug, Clarinex or Allegra, the patient prefers more.
NCT00794495 ↗	Preference for Clarinex Tablets vs. Zyrtec Tablets in Patients With Allergies (P03181)	Completed	Merck Sharp & Dohme Corp.	Phase 4	2002-12-01	This was a crossover study designed to see if patients with allergy symptoms preferred Clarinex® or Zyrtec®. Patients were randomized to take 7 days of Clarinex or Zyrtec treatment, followed by a 5 to 28-day washout period (days when no drug is given), followed by 7 days of the opposite treatment. At the end of each 7-day treatment, patients were asked questions to determine which drug, Clarinex or Zyrtec, the patient prefers more.
NCT00794599 ↗	Preference for Clarinex Tablets vs. Zyrtec Tablets in Patients With Allergies (P03182)	Completed	Merck Sharp & Dohme Corp.	Phase 4	2002-12-01	This was a crossover study designed to see if patients with allergy symptoms preferred Clarinex® or Zyrtec®. Patients were randomized to take 7 days of Clarinex or Zyrtec treatment, followed by a 5 to 28-day washout period (days when no drug is given), followed by 7 days of the opposite treatment. At the end of each 7-day treatment, patients were asked questions to determine which drug, Clarinex or Zyrtec, the patient prefers more.

Clinical Trial Conditions for CLARINEX D 24 HOUR

Condition Name

Condition Name for CLARINEX D 24 HOUR
Intervention	Trials
Seasonal Allergic Rhinitis	7
Healthy	5
Perennial Allergic Rhinitis	3
Allergic Rhinitis	2

Condition MeSH

Condition MeSH for CLARINEX D 24 HOUR
Intervention	Trials
Rhinitis, Allergic	9
Rhinitis	9
Rhinitis, Allergic, Seasonal	7
Rhinitis, Allergic, Perennial	3

Clinical Trial Locations for CLARINEX D 24 HOUR

Trials by Country

Trials by Country for CLARINEX D 24 HOUR
Location	Trials
United States	8
Canada	2

Trials by US State

Trials by US State for CLARINEX D 24 HOUR
Location	Trials
Florida	5
New Jersey	2
Kentucky	1

Clinical Trial Progress for CLARINEX D 24 HOUR

Clinical Trial Phase

Clinical Trial Phase for CLARINEX D 24 HOUR
Clinical Trial Phase	Trials
Phase 4	9
Phase 3	2
Phase 2	1

Clinical Trial Status

Clinical Trial Status for CLARINEX D 24 HOUR
Clinical Trial Phase	Trials
Completed	18
Active, not recruiting	1

Clinical Trial Sponsors for CLARINEX D 24 HOUR

Sponsor Name

Sponsor Name for CLARINEX D 24 HOUR
Sponsor	Trials
Merck Sharp & Dohme Corp.	9
Dr. Reddy's Laboratories Limited	6
Sanofi	2

Sponsor Type

Sponsor Type for CLARINEX D 24 HOUR
Sponsor	Trials
Industry	19
Other	1

Clinical Trials Update, Market Analysis, and Projection for Clarinex D 24 Hour

Last updated: October 28, 2025

Introduction

Clarinex D 24 Hour, a combination formulation of desloratadine and pseudoephedrine, addresses allergic rhinitis with secondary nasal congestion. Marketed primarily in the United States, Clarinex D 24 Hour has carved a niche within antihistamine and decongestant therapies. This analysis offers a comprehensive update on clinical trials, market dynamics, and future projections for this drug, providing critical insights for stakeholders and industry professionals.

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Clinical Trials Update

Current Status and Ongoing Studies

As of 2023, Clarinex D 24 Hour is an established formulation, with no recent large-scale clinical trials actively recruiting or underway specifically for this combination. Its approval stems from prior pivotal studies demonstrating efficacy and safety in allergic rhinitis and sinusitis.

However, continuous post-marketing surveillance and real-world evidence collection form the backbone of ongoing assessment, especially concerning long-term safety profiles. While no new randomized controlled trials (RCTs) are publicly registered recently, broader research has been directed toward comparing newer antihistamine-decongestant combinations and exploring potential for analgesic or additional respiratory indications.

Safety and Efficacy Data

Existing clinical data reaffirm Clarinex D’s efficacy in symptom relief—particularly nasal congestion, sneezing, and rhinorrhea—aligned with previous trials that evidenced rapid onset and sustained symptom control (referenced from the FDA’s summary of clinical pharmacology). Safety profiles remain favorable, with common adverse events including dry mouth, headache, and mild gastrointestinal disturbances, consistent with both desloratadine and pseudoephedrine's known profiles.

Regulatory Position

Clarinex D 24 Hour maintains FDA approval, with the last review in 2009. The drug's safety, efficacy, and formulation have not faced significant regulatory challenges since approval. Future clinical investigations could aim to expand indications or explore drug interactions, especially with evolving allergy treatment landscapes requiring tailored therapeutics.

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Market Analysis

Market Overview

The global allergic rhinitis market is projected to reach approximately $8.4 billion by 2028, growing at a CAGR of around 6% [1]. Key drivers include increased prevalence of allergies, greater awareness, and rising affinity for combination therapies that improve compliance.

Clarinex D’s primary market comprises the U.S., where atop-the-line allergy medications generate substantial revenues. The drug’s once-daily dosing, combined with a well-established safety profile, positions it favorably amid competition.

Competitive Landscape

The competitive environment encompasses both prescription and OTC antihistamines with decongestant components—such as Allegra-D, Zyrtec-D, and Xyzal-D. Generic formulations of pseudoephedrine and desloratadine also intensify price competition.

Innovative therapies, notably biologics like omalizumab, are emerging for severe allergic conditions but remain outside the scope for over-the-counter and mild-to-moderate allergic rhinitis. Nevertheless, newer combination formulations, fixed-dose combinations, and innovative delivery methods are expected to challenge Clarinex D's market share.

Market Dynamics and Distribution Channels

Retail pharmacy outlets, mail-order pharmacies, and increasingly online platforms dominate distribution. Insurance coverage and formulary placement significantly influence prescription volumes.

A critical factor affecting market performance is the regulatory environment around pseudoephedrine sales, with restrictions aimed at combating methamphetamine production potentially impacting supply chain and access.

Market Challenges

• Regulatory restrictions: Pseudoephedrine's controlled status limits ease of access.
• Consumer preferences: Shift toward OTC products or alternative therapies without prescription reimbursement.
• Pricing pressures: Broader availability of generics exerts downward pricing pressure.

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Market Projection and Future Outlook

Growth Drivers

• Increasing prevalence of allergic rhinitis—estimated to affect over 30% of adults and children globally [2].
• Rising consumer preference for once-daily, combination oral therapies that improve compliance.
• Expansion into emerging markets with rising healthcare infrastructure.

Potential Opportunities

• New indications: Research into adjunctive uses for Clarinex D, such as for chronic sinusitis or other upper respiratory tract conditions, could diversify revenue streams.
• Formulation innovations: Development of non-drowsy, long-acting versions or combining with other anti-inflammatory agents.
• Digital health integration: Utilizing app-based monitoring to optimize dosage adherence and symptom tracking.

Forecast Volume and Revenue Trends

Given the matured status of Clarinex D, growth is likely to be modest but steady, driven largely by demographic expansion and formulary favorable positioning. Industry analysts project a compound annual growth rate (CAGR) of approximately 4-6% through 2030, with market expansion focusing on North America and Asia-Pacific regions.

Impact of Competition and Regulatory Changes

While the generic landscape exerts price competition, brand loyalty and physician prescriber habits favor continued sales. However, impending regulatory restrictions on pseudoephedrine sales could suppress demand unless alternative formulations are developed.

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Key Takeaways

• Clinical trials for Clarinex D 24 Hour are mostly complete, with ongoing post-marketing surveillance confirming its safety and efficacy profile.
• Market competition is intense, with generics and OTC alternatives challenging Clarinex D’s market share.
• Regulatory and supply chain restrictions on pseudoephedrine could impact future sales unless addressed through formulation innovations.
• Growing allergy prevalence and consumer preference for convenient, combination therapies support steady market growth.
• Future expansion opportunities include exploring new indications, development of advanced formulations, and digital health integration.

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FAQs

1. Is Clarinex D 24 Hour available over the counter?
No, Clarinex D 24 Hour is a prescription medication in the United States, primarily due to the inclusion of pseudoephedrine, which is regulated to combat misuse.

2. Are there any ongoing clinical trials for Clarinex D?
No recent clinical trials specifically for Clarinex D have been registered; current data is based on prior pivotal studies and post-marketing surveillance.

3. How does Clarinex D compare to other allergy medications?
Clarinex D offers once-daily dosing with a combination of antihistamine and decongestant, providing rapid and sustained relief. Its safety profile is comparable to similar combination therapies, but market competition from generics and OTC options remains fierce.

4. What are the main barriers to market growth for Clarinex D?
Key barriers include regulatory restrictions on pseudoephedrine sales, increasing generic competition, consumer shift toward OTC products, and the emergence of newer therapies with different mechanisms of action.

5. What future developments could influence Clarinex D's market position?
Advances in formulation (non-controlled decongestants), expanded indications, digital health integrations, and reformulation to bypass pseudoephedrine restrictions could strengthen its market stance.

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Conclusion

Clarinex D 24 Hour remains a vital part of allergy management, supported by a robust clinical and safety profile. While its growth faces challenges from regulatory constraints and competitive pressures, demographic trends and consumer preferences sustain its market relevance. Strategic innovations and regulatory adaptations hold potential to enhance its long-term positioning in the allergy therapeutics landscape.

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References

[1] Market Research Future. "Allergic Rhinitis Market Forecast to 2028."
[2] Bousquet, J., et al. "Global prevalence of allergic rhinitis: Systematic review and meta-analysis." Allergy, 2021.