CLINICAL TRIALS PROFILE FOR ETHAMBUTOL HYDROCHLORIDE

505(b)(2) Clinical Trials for ETHAMBUTOL 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	NCT01589497 ↗	Essentiality of INH in TB Therapy	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 2	2015-06-30	Tuberculosis (TB) disease is caused by bacteria that have infected the lung. TB bacteria are very small living agents that are spread by coughing and can be killed by taking TB drugs. To kill these TB bacteria TB patients have to take a combination of four drugs for 2 months and then two drugs for a further 4 months. During the first 2 months patients take rifampicin, isoniazid, ethambutol, and pyrazinamide. After that patients take only isoniazid and rifampicin for a further 4 months, making a total of 6 months therapy. In A5307 the investigators wanted to test a new combination of drugs to see if the investigators could treat TB faster in the future. Studies in animals have suggested that one of the four drugs, isoniazid, only works for a few days and may not be needed after the first two doses of TB treatment to kill the TB bacteria. After that its effects wear off to the point that it may even interfere with the other drugs. The investigators wanted to see if stopping isoniazid early, or using moxifloxacin, a different drug, instead could treat TB faster. This study was the first time that this type of regimen without isoniazid had been tested in humans. If the investigators could show that isoniazid stops working after a few days, the investigators could then try to see if they could possibly make a better tuberculosis treatment in the future.
New Combination	NCT01589497 ↗	Essentiality of INH in TB Therapy	Completed	AIDS Clinical Trials Group	Phase 2	2015-06-30	Tuberculosis (TB) disease is caused by bacteria that have infected the lung. TB bacteria are very small living agents that are spread by coughing and can be killed by taking TB drugs. To kill these TB bacteria TB patients have to take a combination of four drugs for 2 months and then two drugs for a further 4 months. During the first 2 months patients take rifampicin, isoniazid, ethambutol, and pyrazinamide. After that patients take only isoniazid and rifampicin for a further 4 months, making a total of 6 months therapy. In A5307 the investigators wanted to test a new combination of drugs to see if the investigators could treat TB faster in the future. Studies in animals have suggested that one of the four drugs, isoniazid, only works for a few days and may not be needed after the first two doses of TB treatment to kill the TB bacteria. After that its effects wear off to the point that it may even interfere with the other drugs. The investigators wanted to see if stopping isoniazid early, or using moxifloxacin, a different drug, instead could treat TB faster. This study was the first time that this type of regimen without isoniazid had been tested in humans. If the investigators could show that isoniazid stops working after a few days, the investigators could then try to see if they could possibly make a better tuberculosis treatment in the future.

All Clinical Trials for ETHAMBUTOL HYDROCHLORIDE

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00000641 ↗	A Phase II/III Trial of Rifampin, Ciprofloxacin, Clofazimine, Ethambutol, and Amikacin in the Treatment of Disseminated Mycobacterium Avium Infection in HIV-Infected Individuals.	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 2	1969-12-31	To compare the effectiveness and toxicity of two combination drug treatment programs for the treatment of disseminated Mycobacterium avium infection in HIV seropositive patients. [Per 03/06/92 amendment: to evaluate the efficacy of azithromycin when given in conjunction with either ethambutol or clofazimine as maintenance therapy.] Disseminated M. avium infection is the most common systemic bacterial infection complicating AIDS in the United States. The prognosis of patients with disseminated M. avium is extremely poor, particularly when it follows other opportunistic infections or is associated with anemia. Test tube studies and clinical data indicate that the best treatment program may include clofazimine, ethambutol, a rifamycin derivative, and ciprofloxacin. Test tube and animal studies indicate that amikacin is a bactericidal (bacteria destroying) drug that works better when used with ciprofloxacin. Its role in treatment programs is a key issue because of toxicity and because it must be administered parenterally (by injection or intravenously).
NCT00000796 ↗	A Prospective Study of Multidrug Resistance and a Pilot Study of the Safety of and Clinical and Microbiologic Response to Levofloxacin in Combination With Other Antimycobacterial Drugs for Treatment of Multidrug-Resistant Pulmonary Tuberculosis (MDR	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	N/A	1969-12-31	To determine the demographic, behavioral, clinical, and geographic risk factors associated with the occurrence of multidrug-resistant pulmonary tuberculosis (MDRTB). To evaluate the clinical and microbiological responses and overall survival of MDRTB patients who are treated with levofloxacin-containing multiple-drug regimens chosen from a hierarchical list. Per 9/28/94 amendment, to assess whether persistent or recurrent positive sputum cultures of patients who show failure or relapse are due to the same strain or reinfection with a new strain. Among TB patients, there has been an increase in progressive disease due to the emergence of antimycobacterial drug-resistant strains of Mycobacterium tuberculosis. Failure to identify patients at high risk for MDRTB increases the hazard for both treatment failure and development of resistance to additional therapeutic agents. Efforts to improve survival in patients with MDRTB will depend on improved methods of assessing the risk of acquisition of MDRTB and identifying drug susceptibility patterns in a timely fashion.
NCT00000950 ↗	Metabolism of Antituberculosis Drugs in HIV-Infected Persons With Tuberculosis	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	N/A	1969-12-31	The purpose of this study is to determine if a relationship exists between the level of antituberculosis drugs (isoniazid, rifampin, ethambutol, and pyrazinamide) in the blood and the outcome of HIV-positive patients with tuberculosis. This study also evaluates how these drugs are absorbed and metabolized in the body.
NCT00001033 ↗	The Treatment of Tuberculosis in HIV-Infected Patients	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 3	1969-12-31	PER 5/30/95 AMENDMENT: To compare the combined rate of failure during therapy and relapse after therapy between two durations of intermittent therapy (6 versus 9 months) for the treatment of pulmonary tuberculosis (TB) in HIV-infected patients. To compare toxicity, survival, and development of resistance in these two regimens. ORIGINAL: To compare the efficacy and safety of induction and continuation therapies for the treatment of pulmonary TB in HIV-infected patients who are either from areas with known high rates of resistance to one or more anti-TB drugs or from areas where TB is expected to be susceptible to commonly used anti-TB drugs. PER 5/30/95 AMENDMENT: In HIV-negative patients, intermittent anti-TB therapy has been shown to be as effective as daily therapy, but the optimal duration of therapy in HIV-infected patients has not been established. ORIGINAL: In some areas of the country, resistance to one or more of the drugs commonly used to treat TB has emerged. Thus, the need to test regimens containing a new drug exists. Furthermore, the optimal duration of anti-TB therapy for HIV-infected patients with TB needs to be determined.
NCT00001039 ↗	Evaluation of Treatment for Mycobacterium Avium Complex (MAC) Infection in HIV-Infected Patients	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 2	1969-12-31	To assess the feasibility of using culture and staining techniques to quantify tissue Mycobacterium avium Complex (MAC) burden in bone marrow. To correlate and compare changes in MAC bone marrow burden with quantitative MAC blood culture results at baseline and after 4 and 8 weeks of treatment. MAC is easiest to detect in the blood, although doctors generally believe that MAC in blood is just "spill-over" from infection of other parts of the body. Traditionally, studies of potential treatments for MAC focus only on MAC changes in the blood. This study compares MAC changes in blood to those in bone marrow, which is another tissue where MAC is often found.
NCT00001047 ↗	Study of Four Different Treatment Approaches for Patients Who Have Mycobacterium Avium Complex Disease (MAC) Plus AIDS	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 3	1969-12-31	To compare the safety and efficacy of two doses of clarithromycin in combination with ethambutol and either rifabutin or clofazimine for the treatment of disseminated Mycobacterium avium Complex (MAC) disease in AIDS patients. Recommendations have been issued for AIDS patients with disseminated MAC to be treated with at least two antimycobacterial agents and for every regimen to include a macrolide (clarithromycin or azithromycin). However, the optimal treatment for disseminated MAC remains unknown.
NCT00001058 ↗	A Comparison of Three Drug Combinations Containing Clarithromycin in the Treatment of Mycobacterium Avium Complex (MAC) Disease in Patients With AIDS	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	Phase 2	1969-12-31	To compare the efficacy and safety of clarithromycin combined with rifabutin, ethambutol, or both in the treatment of disseminated Mycobacterium avium Complex (MAC) disease in persons with AIDS, including individuals who have or have not received prior MAC prophylaxis. It is believed that effective therapy for MAC disease in patients with AIDS requires combinations of two or more antimycobacterial agents in order to overcome drug resistance and the unfavorable influence of the profound immunosuppression associated with AIDS. Data suggest that clarithromycin may have substantial activity in two- or three-drug combination regimens with clofazimine, rifamycin derivatives, ethambutol, or the 4-quinolones.

Clinical Trial Conditions for ETHAMBUTOL HYDROCHLORIDE

Condition Name

Condition Name for ETHAMBUTOL HYDROCHLORIDE
Intervention	Trials
Tuberculosis	45
Tuberculosis, Pulmonary	17
HIV Infections	15
Pulmonary Tuberculosis	15

Condition MeSH

Condition MeSH for ETHAMBUTOL HYDROCHLORIDE
Intervention	Trials
Tuberculosis	93
Tuberculosis, Pulmonary	46
Mycobacterium Infections	23
HIV Infections	21

Clinical Trial Locations for ETHAMBUTOL HYDROCHLORIDE

Trials by Country

Trials by Country for ETHAMBUTOL HYDROCHLORIDE
Location	Trials
United States	274
China	87
South Africa	43
Uganda	21
Brazil	20

Trials by US State

Trials by US State for ETHAMBUTOL HYDROCHLORIDE
Location	Trials
New York	21
California	20
Texas	19
Maryland	15
Illinois	15

Clinical Trial Progress for ETHAMBUTOL HYDROCHLORIDE

Clinical Trial Phase

Clinical Trial Phase for ETHAMBUTOL HYDROCHLORIDE
Clinical Trial Phase	Trials
PHASE4	4
PHASE3	3
PHASE2	4

Clinical Trial Status

Clinical Trial Status for ETHAMBUTOL HYDROCHLORIDE
Clinical Trial Phase	Trials
Completed	58
Recruiting	32
Not yet recruiting	14

Clinical Trial Sponsors for ETHAMBUTOL HYDROCHLORIDE

Sponsor Name

Sponsor Name for ETHAMBUTOL HYDROCHLORIDE
Sponsor	Trials
National Institute of Allergy and Infectious Diseases (NIAID)	20
Beijing Chest Hospital	9
Centers for Disease Control and Prevention	8

Sponsor Type

Sponsor Type for ETHAMBUTOL HYDROCHLORIDE
Sponsor	Trials
Other	362
Industry	31
NIH	25

ETHAMBUTOL HYDROCHLORIDE Market Analysis and Financial Projection

Last updated: April 24, 2026

Ethambutol Hydrochloride: Clinical-Trials Update, Market Analysis, and 5-Year Projection

Ethambutol hydrochloride is a generic, established anti-tuberculosis (TB) active ingredient used in combination regimens for drug-susceptible and drug-resistant TB. Current economics are driven by World Health Organization (WHO) program procurement, national TB program tender cycles, and the pace of donor-funded demand. Commercial upside is limited by generic competition, but volume stability remains high because ethambutol is a core component of standard TB care.

What is the current clinical-trials landscape for ethambutol hydrochloride?

Ethambutol is long established in TB regimens and has a mature safety and efficacy data package. Clinical-trials activity in recent years typically concentrates on (1) regimen optimization (new combinations, shorter-course strategies), (2) formulation and pharmacokinetic (PK) work, and (3) treatment sequencing for drug-resistant TB rather than new “monotherapy” approvals.

Trial activity pattern (practical read-through for investors)

• Regimen-focused studies: Ethambutol appears in combination arms for TB treatment strategies, including standardized drug-resistant regimens and pilot studies on duration reduction where eligible.
• Formulation/PK studies: Work tends to target bioavailability, dose-exposure alignment, or improved tolerability to reduce ocular toxicity risk.
• Safety monitoring endpoints: Primary safety readouts track visual function and optic neuropathy risk, often with standardized ophthalmology assessments.

Operational constraint that shapes the trials pipeline

• Ethambutol has become embedded into national and donor TB regimens. New clinical evidence that changes standard-of-care must clear high bar because existing regimens already use it and generic pricing suppresses patent-protected “new drug” economics.

What this means for a clinical-trials update

• The most investable developments are typically not new molecular entities but new fixed-dose combinations, pediatric formulations, or regimen protocols that can shift procurement specifications.

Source-aligned baseline on use

• WHO includes ethambutol in recommended TB drug regimens and monitoring frameworks, anchoring its continued inclusion in core treatment pathways. (See WHO TB guidance sources below.) [1], [2]

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How does the market size ethambutol hydrochloride, and what determines pricing?

Ethambutol hydrochloride is sold as a generic ingredient and also as finished tablets in combination or standalone TB regimens. The market is best understood through TB procurement flows and tender volumes rather than branded-commercial sales.

Key market drivers

1. TB program demand (core driver): WHO-aligned national TB programs and Global Fund-supported procurement determine large bulk volumes.
2. Drug-resistant TB share (volume mix driver): Higher proportions of drug-resistant TB can increase daily drug counts and regimen durations, sustaining demand for older TB agents used in combination.
3. Pricing compression (margin driver): Multiple generic suppliers and recurring tender renewals push prices down and shift profit to volume, manufacturing reliability, and regulatory acceptance.
4. Regulatory and quality approvals (access driver): Listing in procurement panels, local registration, and pharmacovigilance performance determine sell-through.

Price formation mechanism

• In typical procurement tender economics, pricing is set by lowest qualified bid and contract terms (incoterms, delivery schedules, shelf life requirements). This makes market share less about differentiation and more about qualification, supply assurance, and cost structure.

Demand stability factor

• Ethambutol remains a standard drug in TB regimens; demand is relatively insulated from class-level substitution because it is a recognized component in multi-drug protocols. WHO guidance supports continued use within recommended regimens. [1], [2]

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What does the competitive landscape look like for ethambutol hydrochloride?

The competitive set is structurally generic and capacity-driven.

Competition characteristics

• Multi-supplier tender market: Manufacturers compete for procurement panels and country registrations.
• Quality-system differentiation: Compliance with GMP, impurity specifications, stability data, and pharmacovigilance expectations can determine eligibility.
• Form factor competition: Fixed-dose combinations and pediatric strengths can affect tender preferences even when the API is identical.

Investment implication

• Supplier advantage comes from manufacturing scale, regulatory track record, and the ability to meet tender shelf-life and delivery requirements. API margin is often thin; returns are most realistic via procurement scale or niche formulations (where tender specs favor a specific presentation).

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What is the 5-year market projection for ethambutol hydrochloride?

A forward projection for a generic API must be expressed in directional terms because pricing is tender-driven and varies materially by region and contracting cycle. The most decision-useful projection is a base-case growth range in revenue and volume, separating volume stability from price pressure.

Projection framework

• Volume: tied to TB incidence trends and drug-resistant TB burden, adjusted by regimen duration and regimen selection.
• Price: tied to competitive intensity and procurement budget cycles.

Base-case view (directional)

• Volume: stable to low-growth, with modest uplift if drug-resistant TB drug counts and regimen complexity rise faster than overall TB decline.
• Revenue: can be flat to modestly declining in markets where tender prices compress, even if volume remains stable.

Directional 5-year outcome (2026–2030)

• Low case: revenue flat to down (continued price pressure, slower TB burden growth, procurement rationing).
• Base case: revenue flat with small gains in select geographies or tender categories; volume stable.
• High case: revenue up modestly where donor and national TB budgets expand, drug-resistant burden increases, or tender specs favor particular formulations.

This base-case projection is consistent with the structural reality that ethambutol is not in a high-cycle “launch” phase. It is a sustained procurement drug with generic price compression.

WHO anchor points for treatment structure

• WHO recommends multi-drug regimens and includes ethambutol as part of standard TB treatment approaches (context for continued demand). [1], [2]

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What could shift demand or buying behavior in the next 2–3 years?

Demand could rise if:

• Drug-resistant TB programs expand and increase the share of regimens requiring ethambutol-containing combinations.
• National procurement cycles normalize after short-term budget or supply disruptions.

Demand could soften if:

• TB programs accelerate regimen simplification that uses alternative drugs for eligible patients, reducing ethambutol inclusion rates in certain subpopulations.
• Procurement agencies tighten cost controls that favor fewer suppliers or concentrate award sizes, squeezing marginal producers.

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Regulatory and quality checkpoints that matter commercially

Even where clinical demand is stable, commercial throughput depends on regulatory acceptability.

Key product requirements in procurement

• GMP compliance and consistent batch release.
• Impurity profile control (including related substances).
• Stability and shelf-life documentation meeting tender shelf-life requirements.
• Pharmacovigilance commitments aligned with national TB program expectations.

Why this matters for market projection

• In a generic API category, qualified-supply constraints can tighten availability and temporarily stabilize pricing, while qualification expansions can increase supply and depress price.

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Key Takeaways

• Ethambutol hydrochloride is in a mature, procurement-led market dominated by generic supply, with clinical trials focused on regimen optimization and formulation/PK work rather than new therapeutic claims. [1], [2]
• Market value is driven by national TB program and donor procurement volumes, not branded product adoption. Pricing faces persistent tender-based compression due to multiple qualified suppliers.
• A realistic 5-year projection is stable volume with flat-to-modest revenue movement: upside appears in geography- or tender-driven procurement mix shifts (including formulation preferences), while downside reflects continued price pressure.
• Commercial differentiation is operational: qualification status, supply reliability, and meeting tender shelf-life and quality specs.

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FAQs

1) Is ethambutol hydrochloride still required in modern TB regimens?

Yes. WHO TB guidance includes ethambutol as part of recommended multi-drug approaches and treatment monitoring frameworks, which supports continued procurement demand. [1], [2]

2) What type of clinical trials dominate for ethambutol now?

Ethambutol trials largely focus on regimen optimization within TB treatment strategies and on formulation/PK or safety monitoring approaches, rather than establishing first-in-class efficacy.

3) What most influences ethambutol prices in practice?

Tender mechanics: qualified bids, contract terms, shelf-life requirements, and supply competition. When more suppliers meet the same tender specs, prices typically compress.

4) Where does growth come from for a generic ethambutol API?

From incremental procurement volume and tender mix shifts, such as increased drug-resistant TB program use or preference for specific presentations (including pediatric strengths or combination formats).

5) What is the biggest commercial risk in the next 5 years?

Sustained pricing pressure from generic competition combined with potential regimen changes in subpopulations that could reduce ethambutol inclusion rates.

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References (APA)

1. World Health Organization. (2022). Treatment of drug-resistant tuberculosis: key recommendations and notes on programmatic management. WHO.
2. World Health Organization. (2024). WHO consolidated guidelines on tuberculosis module 4: treatment drug-susceptible tuberculosis (4th ed.). WHO.