CLINICAL TRIALS PROFILE FOR SULFAMETHOXAZOLE AND TRIMETHOPRIM

505(b)(2) Clinical Trials for Sulfamethoxazole And Trimethoprim

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
New Combination	NCT03431168 ↗	A Novel Regimen to Prevent Malaria and STI in Pregnant Women With HIV	Active, not recruiting	University of Alabama at Birmingham	Phase 2	2018-03-07	More than 3 billion people worldwide are at risk of acquiring malaria and pregnant women living with HIV in Africa are at particular risk. An effective prophylaxis regimen capable of preventing malaria and other common perinatal infections would have great potential to improve adverse birth outcomes. The purpose of this randomized controlled trial is to evaluate a new combination prophylaxis regimen in pregnant women with HIV in Cameroon to determine its efficacy and safety.
OTC	NCT05055544 ↗	Bearberry in the Treatment of Cystitis	Not yet recruiting	University of Pecs	N/A	2021-10-01	The goal of this study is to assess the efficacy of bearberry in uncomplicated cystitis. Uncomplicated cystitis is a disease related to the infection of the urinary bladder. Typical symptoms are dysuria, urinary urgency, and frequent voiding of small volumes. Urinary tract infections are frequent in women, usually treated with antibiotics, since the disease is usually caused by bacteria. Fosfomycin is a frequently used antibiotic for the treatment of uncomplicated cystitis. This medicine is typically prescribed by MDs. However, since uncomplicated cystitis is quite frequent, not all patients visit the doctor when experiencing the symptoms of this disease. The use of over-the-counter products (medicines and food supplements) to alleviate the symptoms is common. One of the most frequently used medicinal plants for this purpose is bearberry. Bearberry is a medicinal plant traditionally used for the treatment of cystitis. Its use is accepted by the European Medicine Agency as traditional herbal medicinal product for relief of symptoms of mild recurrent lower urinary tract infections such as burning sensation during urination and/or frequent urination in women. Although the experience gained during the traditional use and the laboratory experiments support the supposed beneficial effect of bearberry, its clinical efficacy has not been confirmed in well-designed clinical trials in comparison with standard antibiotic therapy. In this study, the efficacy of bearberry will be assessed in comparison with fosfomycin. Premenopausal women experiencing the symptoms of uncomplicated cystitis will be randomly divided into two groups. Since it will be a double-blind trial, neither the participants nor the experimenters will know who is receiving a particular treatment. In group A, patients will receive a single dose of fosfomycin powder dissolved in water and 2 placebo tablets three times a day for 7 days. In group B, patients will receive a single dose of placebo powder dissolved in water and 2 bearberry tablets three times a day for 7 days. At the beginning of the study (day 0) and on day 7, patients will be asked to fill in a questionnaire concerning their symptoms. At the same times, urine specimens will be collected to inspect the presence of bacteria in the urine. The primary goal of the trial is to assess the improvement of symptoms of uncomplicated cystitis after 7 days of treatment with the intention to analyze whether treatment with bearberry is at least as effective as fosfomycin therapy is. This will be achieved by using a validated questionnaire (Acute Cystitis Symptom Score). The presence of bacteria in urine and the frequency and severity of side effects will also be recorded and compared. During a 90-days follow-up of this study, the recurrence of urinary tract infections will be analyzed. This study will deliver important data on the efficacy and safety of bearberry in the treatment of uncomplicated cystitis.

All Clinical Trials for Sulfamethoxazole And Trimethoprim

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00000640 ↗	A Phase III Comparative Study of Dapsone / Trimethoprim and Clindamycin / Primaquine Versus Sulfamethoxazole / Trimethoprim in the Treatment of Mild-to-Moderate PCP in Patients With AIDS	Completed	Glaxo Wellcome	Phase 3	1969-12-31	To evaluate the effectiveness of two oral treatments for mild to moderate Pneumocystis carinii pneumonia (PCP): dapsone/trimethoprim or clindamycin/primaquine as compared to a standard treatment program of sulfamethoxazole/trimethoprim (SMX/TMP) to assess the tolerance of these two alternative treatments as compared to the standard treatment of SMX/TMP. Per 09/09/92 amendment, to assess the efficacy and tolerance of these two alternative treatments in patients who are intolerant to SMX/TMP. The type of treatment being studied has the advantages of wide applicability throughout the world (including developing countries) and low cost. An oral treatment is more accessible to patients than drugs given by injection or by inhalation.
NCT00000640 ↗	A Phase III Comparative Study of Dapsone / Trimethoprim and Clindamycin / Primaquine Versus Sulfamethoxazole / Trimethoprim in the Treatment of Mild-to-Moderate PCP in Patients With AIDS	Completed	Jacobus Pharmaceutical	Phase 3	1969-12-31	To evaluate the effectiveness of two oral treatments for mild to moderate Pneumocystis carinii pneumonia (PCP): dapsone/trimethoprim or clindamycin/primaquine as compared to a standard treatment program of sulfamethoxazole/trimethoprim (SMX/TMP) to assess the tolerance of these two alternative treatments as compared to the standard treatment of SMX/TMP. Per 09/09/92 amendment, to assess the efficacy and tolerance of these two alternative treatments in patients who are intolerant to SMX/TMP. The type of treatment being studied has the advantages of wide applicability throughout the world (including developing countries) and low cost. An oral treatment is more accessible to patients than drugs given by injection or by inhalation.
NCT00000640 ↗	A Phase III Comparative Study of Dapsone / Trimethoprim and Clindamycin / Primaquine Versus Sulfamethoxazole / Trimethoprim in the Treatment of Mild-to-Moderate PCP in Patients With AIDS	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 3	1969-12-31	To evaluate the effectiveness of two oral treatments for mild to moderate Pneumocystis carinii pneumonia (PCP): dapsone/trimethoprim or clindamycin/primaquine as compared to a standard treatment program of sulfamethoxazole/trimethoprim (SMX/TMP) to assess the tolerance of these two alternative treatments as compared to the standard treatment of SMX/TMP. Per 09/09/92 amendment, to assess the efficacy and tolerance of these two alternative treatments in patients who are intolerant to SMX/TMP. The type of treatment being studied has the advantages of wide applicability throughout the world (including developing countries) and low cost. An oral treatment is more accessible to patients than drugs given by injection or by inhalation.
NCT00000655 ↗	A Randomized, Double-Blind Study of 566C80 Versus Septra (Sulfamethoxazole/Trimethoprim) for the Treatment of Pneumocystis Carinii Pneumonia in AIDS Patients	Completed	Glaxo Wellcome	Phase 2	1969-12-31	To evaluate the effectiveness of atovaquone (566C80) compared to a standard antipneumocystis agent, (SMX/TMP), for the treatment of mild to moderate Pneumocystis carinii pneumonia (PCP) in AIDS patients. To compare the safety of short-term (21 days) treatment with 566C80 and SMX/TMP in AIDS patients with an acute episode of PCP. Standard therapies for acute treatment of PCP involve either SMX/TMP or pentamidine isetionate. Although both treatments are equally effective, side effects prevent completion of therapy in 11-55 percent of patients.

Clinical Trial Conditions for Sulfamethoxazole And Trimethoprim

Condition Name

Condition Name for Sulfamethoxazole And Trimethoprim
Intervention	Trials
HIV Infections	36
Pneumonia, Pneumocystis Carinii	27
Urinary Tract Infections	10
Urinary Tract Infection	8

Condition MeSH

Condition MeSH for Sulfamethoxazole And Trimethoprim
Intervention	Trials
HIV Infections	39
Infections	38
Pneumonia	36
Infection	34

Clinical Trial Locations for Sulfamethoxazole And Trimethoprim

Trials by Country

Trials by Country for Sulfamethoxazole And Trimethoprim
Location	Trials
United States	402
France	16
China	16
Canada	15
Mexico	7

Trials by US State

Trials by US State for Sulfamethoxazole And Trimethoprim
Location	Trials
California	33
New York	25
Illinois	24
Pennsylvania	20
Ohio	20

Clinical Trial Progress for Sulfamethoxazole And Trimethoprim

Clinical Trial Phase

Clinical Trial Phase for Sulfamethoxazole And Trimethoprim
Clinical Trial Phase	Trials
PHASE4	7
PHASE2	2
Phase 4	28

Clinical Trial Status

Clinical Trial Status for Sulfamethoxazole And Trimethoprim
Clinical Trial Phase	Trials
Completed	87
Recruiting	19
Terminated	14

Clinical Trial Sponsors for Sulfamethoxazole And Trimethoprim

Sponsor Name

Sponsor Name for Sulfamethoxazole And Trimethoprim
Sponsor	Trials
National Institute of Allergy and Infectious Diseases (NIAID)	31
Glaxo Wellcome	8
National Cancer Institute (NCI)	7

Sponsor Type

Sponsor Type for Sulfamethoxazole And Trimethoprim
Sponsor	Trials
Other	187
NIH	52
Industry	41

Clinical Trials Update, Market Analysis, and Future Projections for Sulfamethoxazole and Trimethoprim

Last updated: October 28, 2025

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Introduction

Sulfamethoxazole and trimethoprim (SMX-TMP), commonly compounded as co-trimoxazole, remain a cornerstone in antimicrobial therapy. Their synergistic mechanism offers broad-spectrum efficacy against bacterial infections, notably urinary tract infections, pneumonia, and resistant strains such as MRSA. The evolving landscape of antimicrobial resistance (AMR), alongside ongoing clinical advancements and market dynamics, shapes the trajectory of SMX-TMP's use and development.

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Clinical Trials Overview

Recent years have seen focused clinical research efforts aimed at optimizing SMX-TMP’s efficacy and expanding its therapeutic applications. The key trial themes include:

1. Addressing Antimicrobial Resistance

A paramount concern is the increasing prevalence of resistant bacterial strains. Multiple phase II and III trials are evaluating SMX-TMP as an alternative or adjunct therapy against resistant pathogens, particularly MRSA. An example is the ongoing study (NCT04618517), assessing SMX-TMP in combination with other antibiotics for resistant pneumonia in hospitalized patients. Preliminary results indicate promising bacterial clearance and tolerability profiles.

2. Novel Indications and Prophylactic Uses

Recent trials aim to explore SMX-TMP beyond traditional indications:

• COVID-19: Preclinical studies suggest immunomodulatory effects, with phase II trials ongoing to assess its role in reducing secondary bacterial infections or cytokine storm severity (NCT04574826).

• Prophylaxis: Trials examine long-term prophylactic use in immunocompromised populations, such as HIV-positive individuals, to prevent opportunistic infections. An example is the ongoing study in Kenya (NCT04566074) evaluating the efficacy of SMX-TMP in preventing Pneumocystis pneumonia.

3. Pharmacokinetics and Dosing Optimization

New phase I studies are investigating optimal dosing regimens to maximize efficacy, minimize toxicity, and reduce resistance emergence, particularly in vulnerable populations such as pediatric and geriatric groups.

4. Safety and Tolerability Studies

FDA and EMA-approved SMX-TMP formulations are being subjected to rigorous post-marketing surveillance trials to monitor adverse events in varied demographics. For example, the ongoing study NCT04821910 focuses on hypersensitivity reactions in patients with comorbidities.

Clinical Trials Landscape Summary

Trial Focus	Phase	Status	Key Insights
Resistance management	II/III	Ongoing	Potential for broader indications
COVID-19 and secondary infections	II	Recruiting	Possible adjunct role in immune modulation
Prophylaxis in immunocompromised	III	Active	Enhanced data on long-term safety
Dosing optimization	I/II	Completed	Preliminary guidelines emerging
Safety and adverse events	Post-marketing	Continuous	Improved understanding of tolerability

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Market Analysis

Current Market Landscape

The global antimicrobial market, valued at approximately USD 45 billion in 2022, increasingly emphasizes antibiotics like SMX-TMP due to rising antimicrobial resistance and the need for cost-effective therapies[^1]. SMX-TMP accounts for a substantial share, primarily driven by its utility in hospitals and outpatient settings, and a well-established safety profile.

Manufacturing and Patent Status

Though originally off-patent in many jurisdictions, a surge in branded formulations and combination variants has maintained competitive positioning. Pfizer’s Bactrim remains the dominant brand, with generic versions available globally, fueling affordability and access.

Regulatory Trends

Regulatory bodies continue to endorse SMX-TMP for multiple indications, but increased scrutiny on antimicrobial stewardship is prompting guidelines emphasizing judicious use, affecting prescribing patterns.

Emerging Market Opportunities

Growth in emerging economies like India and Africa, driven by high infectious disease burdens and limited healthcare resources, presents substantial opportunities. The demand for affordable antibiotics sustains SMX-TMP’s market share, amid efforts to improve distribution channels.

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Market Dynamics & Future Projections

Market Drivers

• Antimicrobial Resistance Crisis: The rise of resistant bacterial strains necessitates effective oral and intravenous options, bolstering demand for SMX-TMP.
• Expanding Indications: Trials targeting resistant pneumonia, UTIs, and prophylaxis could lead to new approved indications, expanding the market.
• Cost-effectiveness: Its affordability remains attractive, especially in public health programs and resource-limited settings.

Market Challenges

• Resistance Development: Growing resistance may curtail usage in certain indications.
• Safety Concerns: Risks of hypersensitivity and adverse effects can limit application in vulnerable groups.
• Regulatory Constraints: Stringent approval processes for new indications may delay market expansion.

Projections (2023–2030)

The antimicrobial market’s CAGR is projected at approximately 4.5%, with SMX-TMP expected to grow at a slightly higher rate (~5-6%) driven by new clinical data and expanded indications[^2]. Geographic expansion in emerging markets is poised to be significant, with Asia-Pacific and Africa expected to account for over 30% of the growth.

Innovations, such as liposomal formulations or combination therapies, could further enhance efficacy and safety, providing competitive advantages. Meanwhile, emphasis on antimicrobial stewardship will shape usage guidelines, influencing market volume.

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Conclusion

Sulfamethoxazole and trimethoprim continue to hold a vital place in infectious disease management. Ongoing clinical trials are likely to solidify, expand, or refine its therapeutic scope, addressing the critical challenge of antimicrobial resistance. Market growth remains robust, driven by increasing global demand, favorable economics, and emerging indications. Nonetheless, resistance patterns and safety considerations will dictate long-term sustainability.

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Key Takeaways

• Ongoing clinical trials focus on combating resistant infections, expanding indications, and optimizing dosing.
• The global market for SMX-TMP is projected to grow consistently, fueled by resistance, affordability, and emerging therapeutic roles.
• Strategic regulatory navigation and innovation will be crucial to capitalize on new clinical insights.
• Antimicrobial stewardship and safety concerns will influence prescribing trends and market dynamics.
• Emerging markets offer substantial growth opportunities, especially where access to affordable antibiotics is prioritized.

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FAQs

1. What are the primary indications for sulfamethoxazole and trimethoprim?
Primarily used for urinary tract infections, pneumonia (including Pneumocystis jirovecii), and certain gastrointestinal infections. Emerging data may broaden its use in resistant bacterial infections and as prophylaxis.

2. Are there significant resistance concerns with SMX-TMP?
Yes. Resistance has been increasing, especially among gram-negative bacteria, reducing efficacy in some settings. Continued surveillance and stewardship are essential.

3. What safety considerations are associated with SMX-TMP?
Potential adverse effects include hypersensitivity reactions, skin rash, hematologic abnormalities, and gastrointestinal disturbances. Risk is higher in immunocompromised and elderly patients.

4. How might upcoming clinical trials influence the market?
Positive results could lead to new indications, regulatory approvals, and market expansion, especially in resistant infections and prophylactic uses.

5. What is the outlook for SMX-TMP in developing countries?
Demand remains high due to cost-effectiveness. Market growth depends on improving access, managing resistance, and integrating into national treatment guidelines.

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Sources:

[1] Grand View Research, "Antimicrobial Market Size & Share," 2022.
[2] Healthcare Market Insights, "Antibiotics Market Projections," 2023.