CLINICAL TRIALS PROFILE FOR GUAIFENESIN

505(b)(2) Clinical Trials for GUAIFENESIN

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
OTC	NCT02157649 ↗	Single Dose Trial of Extended Release Combination Tablet Codeine and Guaifenesin	Completed	Nexgen Pharma, Inc	Phase 1	2014-06-01	The objectives of this study are (a) to determine if drug levels from a single dose of an extended-release Codeine/Guaifenesin tablet are similar to an immediate-release tablet given every four hours containing lower doses considered safe for over-the-counter use; (b) to evaluate if food affects the drug levels of this extended-release Codeine/Guaifenesin tablet after a single administration; and (c) to assess the safety and tolerability of the Codeine/Guaifenesin extended-release and immediate release tablet formulations.

All Clinical Trials for GUAIFENESIN

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00000752 ↗	Preventing Frequent Sinus Infections in HIV-Infected Patients	Withdrawn	Adams Laboratories	Phase 2	1969-12-31	To evaluate the additional effectiveness of an anti-inflammatory nasal spray ( beclomethasone dipropionate ) and a broad spectrum antibiotic ( cefuroxime axetil ) over decongestant ( Deconsal II ) alone, when these agents are given individually or in combination for the prevention of recurrent paranasal sinus infection in patients with HIV infection. To compare the clinical utility of paranasal sinus radiographs with computed tomograms (CTs) in the evaluation and management of HIV-infected patients with recurrent paranasal sinus infection. To determine relevant prognostic factors and the microbiologic etiology of maxillary sinusitis in this patient population. Sinusitis is common among HIV-infected patients and is likely to be recurrent or refractory to traditional therapy, particularly in patients with advanced immunosuppression. An intervention aimed at prevention of recurrent sinus disease in HIV-infected patients appears to be warranted.
NCT00000752 ↗	Preventing Frequent Sinus Infections in HIV-Infected Patients	Withdrawn	Glaxo Wellcome	Phase 2	1969-12-31	To evaluate the additional effectiveness of an anti-inflammatory nasal spray ( beclomethasone dipropionate ) and a broad spectrum antibiotic ( cefuroxime axetil ) over decongestant ( Deconsal II ) alone, when these agents are given individually or in combination for the prevention of recurrent paranasal sinus infection in patients with HIV infection. To compare the clinical utility of paranasal sinus radiographs with computed tomograms (CTs) in the evaluation and management of HIV-infected patients with recurrent paranasal sinus infection. To determine relevant prognostic factors and the microbiologic etiology of maxillary sinusitis in this patient population. Sinusitis is common among HIV-infected patients and is likely to be recurrent or refractory to traditional therapy, particularly in patients with advanced immunosuppression. An intervention aimed at prevention of recurrent sinus disease in HIV-infected patients appears to be warranted.
NCT00000752 ↗	Preventing Frequent Sinus Infections in HIV-Infected Patients	Withdrawn	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 2	1969-12-31	To evaluate the additional effectiveness of an anti-inflammatory nasal spray ( beclomethasone dipropionate ) and a broad spectrum antibiotic ( cefuroxime axetil ) over decongestant ( Deconsal II ) alone, when these agents are given individually or in combination for the prevention of recurrent paranasal sinus infection in patients with HIV infection. To compare the clinical utility of paranasal sinus radiographs with computed tomograms (CTs) in the evaluation and management of HIV-infected patients with recurrent paranasal sinus infection. To determine relevant prognostic factors and the microbiologic etiology of maxillary sinusitis in this patient population. Sinusitis is common among HIV-infected patients and is likely to be recurrent or refractory to traditional therapy, particularly in patients with advanced immunosuppression. An intervention aimed at prevention of recurrent sinus disease in HIV-infected patients appears to be warranted.
NCT00377403 ↗	Treatment of Acute Sinusitis	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 4	2006-10-01	This study will compare the symptom relief provided by 5 cold medicines versus the symptom relief provided by the same 5 cold medicines plus the antibiotic, amoxicillin, in people who have sinus infections. Treatment with amoxicillin may be more effective than treatment with cold medicines alone. Two hundred adult volunteers, aged 18 to 70 years old, with sinus infections will participate in this study for 28 days. Volunteers will receive a 10-day course of either amoxicillin or placebo (substance containing no medication). In addition, all volunteers will receive pain medication, a chest decongestant, nasal decongestants, and cough medicine as needed. Volunteers will be interviewed by telephone on days 0, 3, 7, 10, and 28 following the start of treatment. The study will look at quality of life factors such as change in functional status (ability to perform daily activities) and symptoms, recurrence of the infection, satisfaction with care, and the direct costs of treatment.
NCT00377403 ↗	Treatment of Acute Sinusitis	Completed	Washington University School of Medicine	Phase 4	2006-10-01	This study will compare the symptom relief provided by 5 cold medicines versus the symptom relief provided by the same 5 cold medicines plus the antibiotic, amoxicillin, in people who have sinus infections. Treatment with amoxicillin may be more effective than treatment with cold medicines alone. Two hundred adult volunteers, aged 18 to 70 years old, with sinus infections will participate in this study for 28 days. Volunteers will receive a 10-day course of either amoxicillin or placebo (substance containing no medication). In addition, all volunteers will receive pain medication, a chest decongestant, nasal decongestants, and cough medicine as needed. Volunteers will be interviewed by telephone on days 0, 3, 7, 10, and 28 following the start of treatment. The study will look at quality of life factors such as change in functional status (ability to perform daily activities) and symptoms, recurrence of the infection, satisfaction with care, and the direct costs of treatment.
NCT00857987 ↗	Effectiveness and Safety of the of Guaifenesin, Doxylamine Succinate and Hydrochloride Etafedrine Syrup in Improvement of Symptoms Resulting From Acute Respiratory Infections.	Unknown status	Azidus Brasil	Phase 3	2010-04-01	Evaluate the improvement of the common cold with the use of medication
NCT01062256 ↗	Study of Count Coughs in Subjects With Acute Upper Respiratory Tract Infections	Completed	Wyeth is now a wholly owned subsidiary of Pfizer	N/A	2010-01-01	The objectives of this study are: a) to assess the feasibility and sensitivity of manually count cough bouts over a 4-hour period; b) to assess the effects of buckwheat honey and guaifenesin 400 mg immediate release tablets compared to placebo on the frequency and severity of acute cough due to upper respiratory tract infection and c) to evaluate the correlation between cough bout frequency and subjective assessments of cough severity. The hypotheses to be tested is that 10 ml of buckwheat honey and 400 mg of immediate release guaifenesin will significantly reduce the frequency and severity of cough compared to placebo over a 4-hour evaluation period.

Clinical Trial Conditions for GUAIFENESIN

Condition Name

Condition Name for GUAIFENESIN
Intervention	Trials
Healthy Subjects	9
Cough	5
Common Cold	2
Flu Symptoms	2

Condition MeSH

Condition MeSH for GUAIFENESIN
Intervention	Trials
Infections	7
Infection	6
Communicable Diseases	5
Respiratory Tract Infections	5

Clinical Trial Locations for GUAIFENESIN

Trials by Country

Trials by Country for GUAIFENESIN
Location	Trials
United States	51
Brazil	6
Peru	2
Jordan	2
India	1

Trials by US State

Trials by US State for GUAIFENESIN
Location	Trials
California	4
Kentucky	3
Texas	3
Ohio	3
Illinois	2

Clinical Trial Progress for GUAIFENESIN

Clinical Trial Phase

Clinical Trial Phase for GUAIFENESIN
Clinical Trial Phase	Trials
Phase 4	3
Phase 3	8
Phase 2/Phase 3	1

Clinical Trial Status

Clinical Trial Status for GUAIFENESIN
Clinical Trial Phase	Trials
Completed	24
Withdrawn	3
Unknown status	3

Clinical Trial Sponsors for GUAIFENESIN

Sponsor Name

Sponsor Name for GUAIFENESIN
Sponsor	Trials
Reckitt Benckiser LLC	7
Reckitt Benckiser Inc.	5
EMS	3

Sponsor Type

Sponsor Type for GUAIFENESIN
Sponsor	Trials
Industry	31
Other	5
NIH	2

Guaifenesin Clinical Trials Update, Market Analysis, and Projection

Last updated: April 28, 2026

What is the current clinical-trials footprint for guaifenesin?

Guaifenesin is a widely marketed expectorant (oral) and is long off patent in most jurisdictions. Public, drug-wide “clinical trials updates” are therefore dominated by (1) formulation and bioequivalence studies, (2) symptom-relief efficacy comparisons in acute cough/URI settings, and (3) safety and exposure monitoring in special populations rather than disease-modifying R&D.

Clinical trial activity pattern (typical for guaifenesin)

• Study type: formulation changes, dose form changes (immediate vs extended release), fixed-dose combination products, and short-duration symptomatic efficacy trials.
• Primary endpoints: cough frequency/severity scores, patient-reported improvement, time-to-relief, and rescue medication use.
• Regulatory objective: bridge to marketed use for generics and combination products; safety characterization rather than novel mechanism validation.

Implication for investors/R&D

• Competitive differentiation is usually product-level (dose form, release profile, tolerability) rather than molecule-level.
• The “trial update” for guaifenesin is best interpreted as ongoing market lifecycle maintenance (reformulations and COMBO line extensions), not a pipeline of new clinical efficacy claims at scale.

What does the market look like today for guaifenesin?

Guaifenesin sits in the global over-the-counter (OTC) cough and cold category, primarily as:

• Oral expectorant monotherapy and
• Fixed-dose combinations (commonly with decongestants, antihistamines, or cough suppressants depending on country formulations).

Market structure

• Dominated by generics and private label due to long-standing availability and limited patent defensibility.
• Competition concentrates on:
  • extended-release vs immediate-release differentiation,
  • flavoring and palatability for pediatric/consumer segments,
  • channel execution (pharmacy vs mass vs e-commerce).

Demand drivers

• Seasonal respiratory disease cycles (winter peaks in many geographies).
• OTC self-medication behavior.
• Broad label utility for productive cough due to chest congestion (indication wording varies by regulator and product labeling).

Key commercial constraints

• Price competition compresses margin.
• Label and safety constraints shape allowable pediatric dosing and combination formulations.
• Regulatory scrutiny in some markets can affect combination product viability when safety profiles are challenged.

Where is pricing and share typically headed?

With a mature OTC molecule, the center of gravity is shifting toward:

• Higher share for brands with strong distribution and compliant combination portfolios.
• Volume growth for low-cost generics in markets with aggressive price pressure.
• Margin migration toward products that reduce cost-to-serve (form factor, pack architecture) and those that maintain customer repeat purchase through perceived tolerability.

Projection posture (what matters most)

• Expect steady-to-slow revenue growth driven by population baseline and seasonal volume, offset by unit price pressure.
• Expect portfolio growth via combination products and extended-release forms, not by new molecular approvals.

What is the most likely clinical and regulatory trajectory?

Given the mature status, near-term regulatory and clinical evolution tends to be:

• Continued bioequivalence and formulation filings for generics and authorized generics.
• Continued post-marketing surveillance emphasis in safety-heavy OTC markets.
• Occasional updates to labeling around pediatric dosing schedules and warnings.

Competitive R&D direction

• Companies that win in guaifenesin generally focus on:
  • release technology (immediate vs sustained exposure),
  • acceptable pharmacokinetics in relevant populations,
  • combination fit to local OTC rules.

How do you model revenue growth for a mature OTC expectorant?

For guaifenesin, a practical projection framework is:

• TAM growth: population and OTC incidence cycles.
• Penetration: share of OTC cough/cold regimen usage.
• Unit economics: ASP (average selling price) under price competition.
• Mix: shift from immediate-release to extended-release and from monotherapy to combination.

Scenario set (directional, market-behavior consistent)

Because the molecule is mature, projection uncertainty is mostly about market mix and distribution strength, not about a step-function efficacy change.

Base-case (most likely)

• Volume: modest growth or stable with seasonal variation.
• Price: gradual decline or flat depending on country and competitive intensity.
• Revenue: low-single-digit CAGR.

Bear-case

• Faster price erosion in generics and increased discounting.
• Combination product restrictions reduce some SKU availability.
• Revenue: flat to low growth.

Bull-case

• Mix shift into extended-release and value-oriented packs.
• Strong execution in pharmacy and e-commerce.
• Revenue: mid-single-digit CAGR.

What market projection should you use for guaifenesin?

A credible investor-grade projection for guaifenesin should be framed as global OTC cough and cold expectorant revenue, with growth driven by unit demand plus mix offsetting price declines.

Best-fit headline projection for planning

• Global guaifenesin revenues: low-single-digit CAGR in the next planning window (roughly 3-6 years), with seasonality and price competition the dominant forces.

What changes the projection most

• Combination product regulatory and labeling outcomes.
• Switch in consumer preference toward extended-release formats.
• Generic entry waves in key markets.

Where can new differentiation realistically come from?

For guaifenesin, differentiation opportunities are mostly commercial and formulation-driven:

• Extended-release oral forms to extend dosing intervals.
• Pediatric acceptability (taste masking, dosing devices, adherence).
• Combination optimization aligned with local OTC rules and consumer needs.
• Supply chain and pack architecture improvements that lower cost-to-serve.

What does not move the needle

• Novel mechanism claims are unlikely to emerge as dominant drivers because guaifenesin’s therapeutic positioning is already established and competition is entrenched.

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Key Takeaways

• Guaifenesin is a mature OTC expectorant; current “clinical trial updates” are mainly formulation, bioequivalence, and short-duration symptomatic trials rather than new therapeutic classes.
• Market activity is dominated by generics and combination products; competitive advantage comes from product mix, distribution, and pack economics rather than molecule-level innovation.
• Revenue outlook is structurally constrained by price competition; planning should use low-single-digit growth assumptions in most base-case scenarios, with upside from extended-release and mix.

FAQs

1) Is guaifenesin still an active clinical development target?
Clinical activity is ongoing but typically limited to formulation and bridging studies that support marketed use, generics, and combination line extensions.

2) What endpoints do guaifenesin studies usually measure?
They generally track cough and chest congestion symptom improvement using patient-reported measures and clinician-assessed scoring systems over short time horizons.

3) How do combination products affect guaifenesin market performance?
They can expand consumer reach and improve shelf conversion, but they also increase regulatory and safety sensitivity because product viability depends on local OTC rules.

4) What is the biggest driver of revenue growth for guaifenesin?
Mix and distribution execution, especially shift toward extended-release formats and value pack strategies, because unit price tends to face downward pressure.

5) Does guaifenesin have strong patent-based protection globally?
No. In most markets it is effectively off patent, which keeps competitive pressure high and shifts differentiation toward formulation and commercial execution.

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References

1. US Food and Drug Administration (FDA). OTC Drug Products; Cough, Cold, Allergy; Active Ingredients and Indications (relevant monograph and labeling resources). FDA.
2. European Medicines Agency (EMA). Public assessment documents and product information for cough and cold expectorants (guaifenesin-related product summaries where available). EMA.
3. ClinicalTrials.gov. Search results for guaifenesin (study listings and trial types). National Library of Medicine.