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Isoniazid (H)
Isoniazid (H) is a Nicotinamide analog; first-line antituberculous agent Small molecule drug developed by University College, London. It is currently in Phase 3 development for Tuberculosis (active and latent infection), Drug-susceptible pulmonary and extrapulmonary tuberculosis. Also known as: INH.
Isoniazid inhibits mycobacterial cell wall synthesis by blocking mycolic acid production, which is essential for Mycobacterium tuberculosis survival.
Isoniazid inhibits mycobacterial cell wall synthesis by blocking mycolic acid production, which is essential for Mycobacterium tuberculosis survival. Used for Tuberculosis (active and latent infection), Drug-susceptible pulmonary and extrapulmonary tuberculosis.
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Baseline phase 3 → approval rate
+58.3pp
Industry-wide phase 3 drugs reach approval ~58.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas). -
Anti-infectives pathway favourability
+2.0pp
Microbiological endpoints + non-inferiority designs raise approval rates above baseline.
| Regulator | Country | Likely year | Lag vs FDA |
|---|---|---|---|
| FDA | US | 2028–2030 | — |
| EMA | EU | 2029–2031 | +0.7 yr |
| MHRA | GB | 2029–2031 | +0.7 yr |
| Health Canada | CA | 2029–2032 | +0.9 yr |
| TGA | AU | 2029–2032 | +1.2 yr |
| PMDA | JP | 2029–2032 | +1.5 yr |
| NMPA | CN | 2030–2033 | +2.3 yr |
| MFDS | KR | 2029–2032 | +1.4 yr |
| CDSCO | IN | 2029–2033 | +1.8 yr |
| ANVISA | BR | 2030–2033 | +2.3 yr |
Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).
Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.
At a glance
| Generic name | Isoniazid (H) |
|---|---|
| Also known as | INH |
| Sponsor | University College, London |
| Drug class | Nicotinamide analog; first-line antituberculous agent |
| Target | Enoyl-ACP reductase (InhA); catalase-peroxidase (KatG) |
| Modality | Small molecule |
| Therapeutic area | Infectious Disease |
| Phase | Phase 3 |
Mechanism of action
Isoniazid is a prodrug that requires activation by the mycobacterial enzyme catalase-peroxidase (KatG) to form an isonicotinoyl radical. This activated form binds to mycobacterial enoyl-ACP reductase (InhA), inhibiting the synthesis of mycolic acids that are critical structural components of the mycobacterial cell wall. This disruption of cell wall integrity leads to bacterial death and is bactericidal against actively dividing M. tuberculosis.
Approved indications
- Tuberculosis (active and latent infection)
- Drug-susceptible pulmonary and extrapulmonary tuberculosis
Common side effects
- Peripheral neuropathy
- Hepatotoxicity
- Hypersensitivity reactions
- Drug-induced lupus
- Pyridoxine deficiency
Key clinical trials
- Bedaquiline Roll-out Evidence in Contacts and People Living With HIV to Prevent TB (PHASE2, PHASE3)
- Shortened Regimen for Drug-susceptible TB in Children (PHASE3)
- Digitally Facilitated, Integrated Community and Facility-Based Interventions: The HEART-TB Trial Protocol (NA)
- Asymptomatic TB With Innovative Modified Short-course Regimens (PHASE4)
- ATORvastatin in Pulmonary TUBerculosis: a POPulation PharmacoKinetics -PharmacoDynamics Sub-study (ATORTUB popPK-PD) (PHASE2)
- Phase 2 Trial to Evaluate the Safety and Tolerability and Early Bactericidal Activity of RESP30TB in Tuberculosis (PHASE2)
- Determination of Adequate Tuberculosis Regimen in Patients Hospitalized With HIV-associated Severe Immune Suppression (PHASE3)
- Rifapentine and Isoniazid TB Preventive Therapy (3HP) for Children Taking Dolutegravir-based Antiretroviral Treatment (DOLPHIN KIDS) (PHASE1, PHASE2)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Isoniazid (H) CI brief — competitive landscape report
- Isoniazid (H) updates RSS · CI watch RSS
- University College, London portfolio CI
Frequently asked questions about Isoniazid (H)
What is Isoniazid (H)?
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Is Isoniazid (H) also known as anything else?
What drug class is Isoniazid (H) in?
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Related
- Drug class: All Nicotinamide analog; first-line antituberculous agent drugs
- Target: All drugs targeting Enoyl-ACP reductase (InhA); catalase-peroxidase (KatG)
- Manufacturer: University College, London — full pipeline
- Therapeutic area: All drugs in Infectious Disease
- Indication: Drugs for Tuberculosis (active and latent infection)
- Indication: Drugs for Drug-susceptible pulmonary and extrapulmonary tuberculosis
- Also known as: INH
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing