CLINICAL TRIALS PROFILE FOR TRIMETHOPRIM HYDROCHLORIDE

505(b)(2) Clinical Trials for trimethoprim hydrochloride

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 hydrochloride

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.
NCT00000655 ↗	A Randomized, Double-Blind Study of 566C80 Versus Septra (Sulfamethoxazole/Trimethoprim) for the Treatment of Pneumocystis Carinii Pneumonia in AIDS Patients	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	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.
NCT00000666 ↗	A Randomized Prospective Study of Pyrimethamine Therapy for Prevention of Toxoplasmic Encephalitis in HIV-Infected Individuals With Serologic Evidence of Latent Toxoplasma Gondii Infection	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	N/A	1969-12-31	To evaluate pyrimethamine as a prophylactic agent against toxoplasmic encephalitis in individuals who are coinfected with HIV and latent Toxoplasma gondii. Toxoplasmic encephalitis is a major cause of illness and death in AIDS patients. Standard treatment for toxoplasmic encephalitis is to combine pyrimethamine and sulfadiazine. Continuous treatment is necessary to prevent recurrence of the disease, but constant use of pyrimethamine/sulfadiazine is associated with toxicity. Clindamycin has been shown to be effective in treatment of toxoplasmic encephalitis in animal studies. This study evaluates pyrimethamine as a preventive treatment against toxoplasmic encephalitis (per 3/26/91 amendment, clindamycin arm was discontinued).
NCT00000714 ↗	An Open, Prospective, Multicenter Study of Trimetrexate With Leucovorin Rescue for AIDS Patients With Pneumocystis Carinii Pneumonia (PCP) and Serious Intolerance to Approved Therapies	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 3	1969-12-31	To determine the safety and effectiveness of an investigational drug therapy (trimetrexate plus leucovorin calcium (TMTX / LCV)) in the treatment of Pneumocystis carinii pneumonia (PCP) in patients who have AIDS, are HIV positive, or are at high risk for HIV infection, and who have suffered severe or life-threatening ill effects from both conventional therapies for PCP. AMENDED: 08/01/90 As of August 31, 1989, 437 patients were enrolled into uncontrolled studies of trimetrexate for PCP:214 in TX 301/ACTG 0=039 (trimetrexate for patients intolerant of approved therapies) and 223 in NS 401 (trimetrexate for patients refractory to approved therapies). The analysis of overall response rate, stringently defined as having received at least 14 days of trimetrexate and being alive at follow-up 1 month after the completion of therapy, reveals 84/159 intolerant patients and 48/160 refractory patients had responded, for rates of 53 percent and 30 percent, respectively. These response rates include all individuals who received at least one dose of trimetrexate. Of the 111 patients who were ventilator-dependent at study entry, 18 completed a course of therapy and were alive a month later, for a response rate of 16 percent. All other ventilated patients died. The most common severe (grades 3 and 4) toxicities were: transaminase elevation (> 5 x normal) in 94 patients, anemia (< 7.9 g/dl) in 109, neutropenia (< 750 cells/mm3) in 58, fever (> 40 C) in 37, and thrombocytopenia (< 50000 platelets/mm3) in 27. Toxicity required discontinuation of therapy in approximately 5 percent of all patients. Original design: The drugs usually used to treat PCP in AIDS patients, trimethoprim / sulfamethoxazole and pentamidine, have had to be discontinued in many patients because of severe side effects. Currently there are no proven alternatives to these drugs. TMTX was chosen for this trial because it was found to be very active against the PCP organism in laboratory tests. Also TMTX, in combination with LCV, had a high response rate and did not cause severe toxicity in a preliminary trial.

Clinical Trial Conditions for trimethoprim hydrochloride

Condition Name

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

Condition MeSH

Condition MeSH for trimethoprim hydrochloride
Intervention	Trials
Infections	42
Pneumonia	41
HIV Infections	39
Infection	36

Clinical Trial Locations for trimethoprim hydrochloride

Trials by Country

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

Trials by US State

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

Clinical Trial Progress for trimethoprim hydrochloride

Clinical Trial Phase

Clinical Trial Phase for trimethoprim hydrochloride
Clinical Trial Phase	Trials
PHASE4	9
PHASE2	5
PHASE1	2

Clinical Trial Status

Clinical Trial Status for trimethoprim hydrochloride
Clinical Trial Phase	Trials
Completed	105
Recruiting	29
Unknown status	15

Clinical Trial Sponsors for trimethoprim hydrochloride

Sponsor Name

Sponsor Name for trimethoprim hydrochloride
Sponsor	Trials
National Institute of Allergy and Infectious Diseases (NIAID)	32
Glaxo Wellcome	8
University of California, San Francisco	7

Sponsor Type

Sponsor Type for trimethoprim hydrochloride
Sponsor	Trials
Other	255
NIH	55
Industry	53

Trimethoprim Hydrochloride clinical trials update, market analysis and forecast: trial status, competitive landscape, and pricing-driven revenue outlook

Last updated: July 28, 2026

Trimethoprim hydrochloride (TMP-HCl) is an established, off-patent antibacterial used as a monotherapy or in fixed combinations, most notably with sulfamethoxazole (co-trimoxazole/trimethoprim-sulfamethoxazole). It has multiple approved regimens and broad generic availability. On that basis, near-term commercial upside is constrained by generic competition and price erosion, with revenue primarily driven by pediatric/adolescent indications, outpatient/community use, and stewardship-linked prescribing rather than by new clinical entrants with differentiated IP.

How are clinical trials for trimethoprim hydrochloride progressing in 2024-2026?

Answer: No current phase-advanced, label-changing trimethoprim hydrochloride program is identifiable from the provided context. TMP-HCl’s clinical footprint is largely dominated by formulation, bioequivalence, resistance/real-world effectiveness studies, and combination trials that focus on comparator regimens rather than TMP-HCl novelty.

What types of TMP-HCl studies show up most often?

• Bioequivalence and formulation studies for oral tablets/capsules and commonly used fixed-dose combinations.
• Antimicrobial resistance and pharmacodynamics work that maps outcomes to dosing schedules.
• Real-world outcomes studies in urinary tract infection (UTI), skin/soft tissue infections (SSTI), and infectious diarrhea or traveler’s diarrhea regimens where trimethoprim-based therapy is used locally.
• Combination studies where TMP-HCl dosing is held constant while comparator antibiotics change.

Which indications are most consistently represented?

• Uncomplicated and complicated UTIs (especially where local susceptibility supports TMP-based therapy).
• Acute bacterial exacerbations and other outpatient bacterial syndromes where guideline placement depends on resistance patterns.
• Pneumocystis jirovecii pneumonia (PJP) prophylaxis regimens in specific populations when TMP-based prophylaxis is used, generally via combination products.

Is there evidence of a late-stage “new trimethoprim” pipeline?

For TMP-HCl as a standalone API, late-stage “new chemical entity” style development is generally limited because the molecule is old and widely genericized. Most competitive activity clusters around:

• Switching, co-packaging, and combination repositioning
• Pediatric formulations
• Resistance-guided stewardship claims tied to local epidemiology rather than new pharmacology

What is the current market structure for trimethoprim hydrochloride and its combinations?

Answer: The market is highly fragmented and generic-led, with co-trimoxazole capturing a majority share in therapeutic use where TMP is prescribed. Pricing is set by commoditization, tender cycles, and payer formularies rather than by brand monopoly.

Key market channels

• Hospital outpatient and emergency departments for uncomplicated bacterial infections where TMP-based options remain guideline-concordant.
• Community pharmacies for routine infectious disease prescriptions.
• Public health procurement in geographies where TMP-based therapy is part of national standard treatment.

What drives demand for TMP-based therapy?

• Susceptibility and resistance trends in target pathogens (E. coli, Klebsiella, Staphylococcus species where relevant).
• Payer formularies and guideline inclusion.
• Combination preference because TMP-HCl monotherapy is less broadly used than fixed combination therapy in many settings.

Price and reimbursement reality

• Generic price compression is the primary force limiting revenue growth.
• Tender-driven procurement often sets the floor price, while supply continuity can dictate premium volume allocation.

How big is the trimethoprim hydrochloride market and where does revenue concentrate?

Answer: TMP-HCl revenue is inseparable from combination product demand in practice. Market concentration is strongest in countries with wide co-trimoxazole utilization for UTIs and in pediatric use patterns where dosing flexibility matters.

Revenue concentration by product form

• Oral tablets/capsules dominate outpatient use.
• Pediatric suspensions matter where liquid dosing is required and where manufacturers compete on taste/volume and stability.
• Fixed combination products dominate therapeutic share because they match common guideline regimens more closely.

Geography patterns

• High outpatient antibiotic volume regions and public procurement ecosystems tend to show higher absolute sales.
• Resistance-sensitive geographies can dampen TMP share as guidelines rotate toward alternatives.

When does trimethoprim hydrochloride lose exclusivity, and do any patents still matter commercially?

Answer: TMP-HCl is not meaningfully protected by enforceable, composition-defining exclusivity in major markets today. Any remaining IP tends to be formulation-specific, dosing regimen-specific, or branding-era residuals that do not generally block generic entry.

Practical implication for commercial planning

• Revenue expansion is unlikely to come from legal exclusivity.
• Competitive advantage is typically manufacturing cost, supply reliability, and portfolio breadth across strengths and forms.

Which patents protect trimethoprim hydrochloride and what coverage still exists?

Answer: Broad composition and early method-of-use coverage is functionally expired. Coverage, if any, is usually limited to:

• Specific formulation approaches (excipients, dissolution targets, or pediatric suspension characteristics)
• Specific fixed-dose combinations in certain jurisdictions (rarely a durable barrier due to multiple generic suppliers)
• Manufacturing process or polymorph-related claims (more plausible in formulation-specific continuations)

How to think about “patent estate strength” for TMP-HCl

• The estate is typically weak in blocking generic entry and strong mainly where a company has a local formulation advantage.
• Any litigation risk tends to be low versus newer antibiotics or niche biologics, unless a specific formulation or combination regains attention.

What is the Orange Book status of trimethoprim hydrochloride?

Answer: Trimethoprim hydrochloride is widely represented as an approved generic and in many combo entries. The Orange Book status is typically characterized by multiple ANDA approvals and limited remaining innovator exclusivity.

What to expect in typical Orange Book listings

• Multiple entries with different NDA references for combination vs monotherapy.
• Patent listings, if present, usually correspond to packaging, formulation, or use claims that are often no longer enforceable against generics.

What generic entry risks exist for trimethoprim hydrochloride?

Answer: Generic entry risk is structurally high because the core API is mature and widely produced. For incumbents, the “risk” is usually not delayed generic entry but:

• Continuous price pressure
• Capacity shocks
• Quality system compliance events
• Tender re-bids replacing suppliers

Market entry barriers that still matter

• GMP and quality consistency
• Regulatory compliance history
• Bioequivalence package quality
• Ability to supply during antibiotic demand spikes

What patent litigation affects trimethoprim hydrochloride?

Answer: Active, high-impact patent litigation tied to the core TMP-HCl API is not a defining feature of the current landscape. Litigation tends to appear sporadically around:

• Specific formulation patents in certain jurisdictions
• ANDA-related disputes where parties claim patent non-infringement or invalidity

Commercial effect of litigation in this category

Even when litigation occurs, market pricing and tender structures typically move quickly toward consolidation among low-cost, high-reliability suppliers.

How does trimethoprim hydrochloride compare with alternative UTI antibiotics for forecasted share?

Answer: TMP-based therapy competes primarily on:

• Cost
• Route convenience
• Local susceptibility and resistance
• Tolerance profile

Where TMP-based therapy loses share

• High resistance in key pathogens leading to guideline exclusion.
• Safety concerns driving clinician pivot toward alternatives.
• Formulary changes following antimicrobial stewardship audits.

Where TMP-based therapy holds share

• Moderate resistance where guidelines still allow TMP options.
• Outpatient preference where TMP-based therapy is familiar, easy to prescribe, and stable.

What do clinical outcomes and stewardship trends imply for future TMP-HCl demand?

Answer: TMP-HCl demand is expected to track guideline placement and resistance ecology rather than a growth curve tied to new clinical breakthroughs. Expect:

• Stable or modestly declining volume if resistance continues to rise.
• Cycling shares depending on susceptibility patterns.
• Periodic substitution into and out of empiric therapy algorithms.

Market projection for trimethoprim hydrochloride through 2027-2029

Answer: The base case is volume stability with pricing pressure, leading to flat to low single-digit growth in revenue globally, with regional variation driven by resistance trends and procurement cycles.

Revenue drivers

• Volume: influenced by outpatient infection volume and pediatric use.
• Price: influenced by tender floors and supply dynamics.
• Mix: generic product mix between monotherapy and fixed combination products.

Forecast scenarios (directional)

• Base case: flat volume, continued price erosion, modest regional share churn.
• Downside: worsening resistance shifts guidelines away from TMP-based therapy in major pathogens, reducing volume.
• Upside: sustained susceptibility keeps TMP in guideline recommendations and procurement cycles favor available suppliers, supporting volume.

Competitive implications

• Companies with broad strength coverage, liquid formulations, and high manufacturing reliability should capture a larger share of supply-constrained tender cycles.
• Companies relying on narrow SKUs face higher substitution risk.

Key product commercialization themes for TMP-HCl in the near term

1. Pediatric oral formulations: demand persists where liquid dosing is required and where taste and stability enable compliance.
2. Fixed-dose combinations: co-trimoxazole remains the main commercial locus.
3. Supply-chain reliability: procurement is often won by dependable delivery rather than differentiation.
4. Stewardship alignment: products benefit when local guidance continues to include TMP-based therapy for defined indications.

Key Takeaways

• Trimethoprim hydrochloride is an established, highly generic antibacterial; commercial upside is constrained by commoditization rather than exclusivity.
• Clinical activity is most often bioequivalence/formulation and real-world effectiveness work; no label-changing late-stage TMP-HCl program is identifiable from the provided context.
• Market growth should be modeled as volume-linked to guideline placement and resistance ecology, with revenue limited by price compression.
• The competitive center of gravity is manufacturing reliability, SKU breadth, and fixed-combination mix, not IP differentiation.

FAQs

1. Why is trimethoprim-sulfamethoxazole (co-trimoxazole) commercial more important than trimethoprim hydrochloride monotherapy?
2. How do rising E. coli resistance patterns change trimethoprim prescribing and revenue forecasts?
3. What product strengths and dosage forms (tablets vs pediatric suspensions) drive tender wins in generic TMP markets?
4. How should investors model tender-based pricing risk for established generic antibiotics like TMP-HCl?
5. What safety and stewardship factors most influence formulary inclusion for TMP-based therapies?

References

1. FDA Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations. U.S. Food and Drug Administration.