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Isoniazid (INH)
Isoniazid inhibits mycobacterial cell wall synthesis by interfering with mycolic acid production, thereby killing Mycobacterium tuberculosis.
Isoniazid inhibits mycobacterial cell wall synthesis by interfering with mycolic acid production, thereby killing Mycobacterium tuberculosis. Used for Tuberculosis (active disease), Tuberculosis prophylaxis (latent TB infection).
At a glance
| Generic name | Isoniazid (INH) |
|---|---|
| Also known as | Generic (various), isonicotinyl hydrazine, |
| Sponsor | National Institutes of Health Clinical Center (CC) |
| Drug class | Antituberculous agent |
| Target | InhA (enoyl-ACP reductase) |
| Modality | Small molecule |
| Therapeutic area | Infectious Disease |
| Phase | FDA-approved |
Mechanism of action
Isoniazid is a prodrug that requires activation by the mycobacterial enzyme catalase-peroxidase (KatG) to form an isonicotinoyl radical, which then inhibits InhA, an enoyl-ACP reductase essential for mycolic acid synthesis. Mycolic acids are critical components of the mycobacterial cell wall, and their disruption leads to cell wall instability and bacterial death. This mechanism is selective for mycobacteria, making it highly effective against tuberculosis.
Approved indications
- Tuberculosis (active disease)
- Tuberculosis prophylaxis (latent TB infection)
Common side effects
- Peripheral neuropathy
- Hepatotoxicity
- Hypersensitivity reactions
- Drug-induced lupus
- Nausea
Key clinical trials
- Bedaquiline Roll-out Evidence in Contacts and People Living With HIV to Prevent TB (PHASE2, PHASE3)
- Safety and Tolerability of Metformin in People With Tuberculosis (TB) and Human Immunodeficiency Virus (HIV) (PHASE2)
- Shortened Regimen for Drug-susceptible TB in Children (PHASE3)
- An Adaptive Multi-arm Trial to Improve Clinical Outcomes Among Children Recovering From Complicated SAM (PHASE3)
- Trial of Novel Regimens for the Treatment of Pulmonary Tuberculosis (PHASE2)
- Isoniazid-Related Hepatotoxicity in Clinical Practice: Incidence and Predictors
- AIPH-TB: AI-Optimised Pyrazinamide-Hydroxychloroquine vs Standard RIPE for Drug-Sensitive Pulmonary Tuberculosis - A Phase II RCT (PHASE2)
- Phase 2a Trial of Alpibectir Plus Ethionamide for Tuberculosis Meningitis (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 |