CLINICAL TRIALS PROFILE FOR TRIMETHOPRIM

505(b)(2) Clinical Trials for 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 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 trimethoprim

Condition Name

Condition Name for trimethoprim
Intervention	Trials
HIV Infections	36
Pneumonia, Pneumocystis Carinii	27
Urinary Tract Infection	11
Urinary Tract Infections	11

Condition MeSH

Condition MeSH for trimethoprim
Intervention	Trials
Infections	41
Pneumonia	40
HIV Infections	39
Infection	36

Clinical Trial Locations for trimethoprim

Trials by Country

Trials by Country for trimethoprim
Location	Trials
United States	445
Canada	21
China	16
France	16
Netherlands	12

Trials by US State

Trials by US State for trimethoprim
Location	Trials
California	35
New York	27
Illinois	24
Pennsylvania	24
Ohio	23

Clinical Trial Progress for trimethoprim

Clinical Trial Phase

Clinical Trial Phase for trimethoprim
Clinical Trial Phase	Trials
PHASE4	8
PHASE2	5
PHASE1	1

Clinical Trial Status

Clinical Trial Status for trimethoprim
Clinical Trial Phase	Trials
Completed	105
Recruiting	29
Terminated	15

Clinical Trial Sponsors for trimethoprim

Sponsor Name

Sponsor Name for trimethoprim
Sponsor	Trials
National Institute of Allergy and Infectious Diseases (NIAID)	32
Glaxo Wellcome	8
National Cancer Institute (NCI)	7

Sponsor Type

Sponsor Type for trimethoprim
Sponsor	Trials
Other	253
NIH	55
Industry	53

Clinical Trials Update, Market Analysis, and Projection for Trimethoprim

Last updated: October 30, 2025

Introduction

Trimethoprim, an antibiotic chiefly used to treat bacterial infections, has played a significant role in antimicrobial therapy since its introduction in the 1960s. As resistance patterns evolve and new pharmaceutical innovations emerge, understanding its clinical development trajectory, market dynamics, and future outlook becomes crucial for stakeholders—from pharmaceutical companies and healthcare providers to investors and policymakers. This analysis synthesizes the latest clinical trial updates, market insights, and future projections for trimethoprim.

Clinical Trials Update

Current Research and Indications

Trimethoprim’s traditional applications include urinary tract infections (UTIs), respiratory tract infections, and otitis media. However, recent clinical trials aim to expand its therapeutic profile, optimize dosing strategies, and combat antimicrobial resistance.

• Combination Therapy for MRSA: Several ongoing trials (NCT04513486, NCT03965287) investigate trimethoprim in combination with sulfamethoxazole or other agents to address methicillin-resistant Staphylococcus aureus (MRSA) infections. Early results indicate enhanced efficacy, particularly in bloodstream infections and skin and soft tissue infections.

• Antimicrobial Resistance Mechanisms: Multiple studies are analyzing the effects of trimethoprim on bacterial resistance genes, especially dfr genes responsible for drug resistance. These investigations aim to identify resistance patterns and develop strategies to mitigate therapeutic failure.

• Malaria and Protozoal Infections: Preliminary trials are evaluating trimethoprim’s efficacy against protozoan diseases such as Leishmania and plasmodium species, considering its antifolate mechanism. These studies are in early phases, primarily phase I or II.

Drug Resistance Trends and Clinical Trial Challenges

Increasing resistance to trimethoprim complicates its clinical utility. Surveillance studies (e.g., CDC's Antibiotic Resistance Threats Report) indicate rising resistance rates among urinary pathogens, notably E. coli, which limit empirical use. Consequently, ongoing trials focus on dosage adjustments, combination therapies, and stewardship initiatives to prolong efficacy.

Regulatory and Developmental Landscape

Despite decades of use, trimethoprim remains off-patent, limiting incentives for novel clinical trials. Nonetheless, the drug’s role in combination therapies and resistance mitigation retains industry interest. Regulatory agencies, including the FDA and EMA, continue to evaluate existing data, mainly emphasizing safety and resistance management strategies.

Market Analysis

Global Market Size and Segmentation

The trimethoprim market, primarily driven by its combination with sulfamethoxazole (co-formulation as co-trimoxazole), was valued at approximately $765 million in 2022, with a compound annual growth rate (CAGR) of around 3% projected through 2030[1].

• Application Segments:

  • Urinary Tract Infections (UTIs): Dominating the market segment, accounting for nearly 65% of prescriptions.
  • Respiratory Infections: About 20%, especially in regions with high antibiotic use.
  • Other: Including skin infections, protozoal diseases, and off-label uses.

• Regional Trends:

  • North America: Holds the largest share, driven by high healthcare expenditure, advanced diagnostic infrastructure, and antimicrobial stewardship.
  • Europe: Stable growth, constrained by resistance concerns and prescribing guidelines.
  • Asia-Pacific: Fastest growth (CAGR ~5%) due to increasing infection prevalence, rising healthcare access, and generic availability.

Market Drivers

• Rising Incidence of Bacterial Infections: Especially UTIs among aging populations and immunocompromised individuals.
• Antimicrobial Stewardship Initiatives: Push towards optimized antibiotic use, promoting combination therapies involving trimethoprim.
• Generic Availability and Cost-Effectiveness: As off-patent drugs, trimethoprim-generics drive affordability and widespread use.

Market Challenges

• Antimicrobial Resistance (AMR): Growing resistance reduces clinical utility, leading to decreased prescriptions and necessitating alternative therapies.
• Regulatory and Prescribing Guidelines: Stricter regulations and cautious prescribing practices in high-income regions dampen growth prospects.
• Emergence of New Antibiotics: Newer agents with activity against resistant strains threaten traditional trimethoprim demand.

Competitive Landscape

Major pharmaceutical companies focus on combination formulations and new derivatives to combat resistance:

• GlaxoSmithKline: Continues to produce co-trimoxazole generics.
• Teva Pharmaceuticals: A significant supplier of generic trimethoprim.
• Innovative Biotech Firms: Exploring novel antifolate compounds to address resistance.

Future Market Projection

Growth Outlook (2023-2030)

Despite challenges, the trimethoprim market is projected to expand modestly, driven by unmet needs in resistant infections and emerging indications. The market is expected to reach $950 million by 2030, growing at a CAGR of 4%.

Key Factors Influencing Growth

• Increased Resistance and Need for Combination Therapy: Drives demand for optimized formulations and adjunct therapies.
• Expansion into Emerging Markets: Growing healthcare infrastructure will foster increased usage in Asia-Pacific and Latin America.
• Research into New Indications: Trials exploring antifolate activity against protozoal and parasitic infections may open new markets.

Potential Disruptors

• Enhanced Resistance Patterns: Could further limit clinical effectiveness, prompting the development of new analogs.
• Development of Novel Antimicrobials: Especially agents offering activity against multi-drug resistant organisms.
• Regulatory and Stewardship Policies: Stricter controls may restrict overuse, impacting volume growth.

Conclusion

Trimethoprim remains a cornerstone antibiotic, predominantly used against urinary and respiratory infections. Its clinical landscape is evolving amidst rising antimicrobial resistance, ongoing clinical trials focusing on combination therapies, and efforts to extend its utility into resistant infections and other disease areas. While market growth is steady, future prospects hinge on addressing resistance challenges, innovating formulations, and expanding into emerging markets.

Key Takeaways

• Clinical trials are actively exploring trimethoprim combinations and new indications, with resistance management being a primary focus.
• The global market is valued at approximately $765 million (2022), with moderate growth projections driven by rise in bacterial infections, generics, and regional expansion.
• Resistance trends threaten long-term utility; ongoing research aims to mitigate this through optimized dosing and combination therapies.
• Market growth will benefit from increased demand in emerging markets and potential new therapeutic uses.
• Strategic investments in research, stewardship policies, and global access are critical to sustain trimethoprim’s role in infectious disease therapy.

FAQs

Q1: How does antimicrobial resistance impact trimethoprim's clinical efficacy?
A: Rising resistance, particularly via dfr gene mutations in bacteria, reduces trimethoprim’s effectiveness, leading clinicians to favor alternative antibiotics or combination therapies. Ongoing research aims to restore its utility.

Q2: Are there any new formulations or derivatives of trimethoprim under development?
A: Currently, most development focuses on combination formulations with sulfamethoxazole. Rare efforts aim to develop novel antifolate agents or modifications to overcome resistance, but none are in advanced clinical stages.

Q3: What are the primary markets driving growth for trimethoprim?
A: North America and Europe dominate due to high prescription rates and stewardship policies, while Asia-Pacific is experiencing rapid growth due to increasing infection rates and expanding healthcare access.

Q4: Can trimethoprim be used to treat infections beyond bacteria?
A: Preliminary studies suggest potential against protozoal infections such as Leishmania and Plasmodium, but these are still exploratory with limited clinical applications.

Q5: How might antimicrobial stewardship affect the future availability of trimethoprim?
A: Stricter stewardship promoting rational use could limit unnecessary prescriptions, potentially constraining market growth but also prolonging drug efficacy when used judiciously.

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References

[1] MarketResearch.com, Global Antibiotics Market Report, 2022.