What is the treatment for Latent Tuberculosis (TB) infection?

From the Guidelines

Latent tuberculosis infection should be treated with one of the preferred rifamycin-based regimens, including 3 months of once-weekly isoniazid plus rifapentine, 4 months of daily rifampin, or 3 months of daily isoniazid plus rifampin, as these regimens have been shown to be effective and have high treatment completion rates 1. The treatment of latent tuberculosis infection (LTBI) is crucial to prevent progression to active TB disease. The preferred regimens are based on the latest guidelines from the National Tuberculosis Controllers Association and CDC, published in 2020 1.

Key Considerations

• Before starting treatment, active TB disease must be ruled out through symptom screening, chest X-ray, and sometimes sputum testing.
• Baseline liver function tests are recommended, especially for those with risk factors for hepatotoxicity.
• Monthly monitoring for adverse effects is essential during treatment.
• Patients should be educated about potential side effects, including hepatotoxicity (symptoms include nausea, vomiting, abdominal pain, jaundice), and drug interactions, particularly with rifampin and rifapentine.

Treatment Options

• Once-weekly isoniazid plus rifapentine for 3 months (3HP) is a preferred regimen, consisting of isoniazid 15 mg/kg (maximum 900 mg) plus rifapentine 600-900 mg (weight-based) once weekly for 12 weeks.
• Alternative options include daily isoniazid for 6-9 months (300 mg daily for adults), daily rifampin for 4 months (600 mg daily for adults), or daily isoniazid plus rifampin for 3 months.
• Treatment completion is crucial for effectiveness, with directly observed therapy sometimes used to ensure adherence.
• These medications prevent active TB by eliminating dormant tuberculosis bacteria before they can reactivate and cause disease, with treatment reducing the risk of progression by 60-90% depending on the regimen used 1.

From the FDA Drug Label

PRIFTIN is indicated in adults and children 2 years and older for the treatment of latent tuberculosis infection caused by Mycobacterium tuberculosis in patients at high risk of progression to tuberculosis disease PRIFTIN must always be used in combination with isoniazid as a 12-week once-weekly regimen for the treatment of latent tuberculosis infection The recommended dose of PRIFTIN should be determined based on weight of the patient up to a maximum of 900 mg once weekly The recommended dose of isoniazid is 15 mg/kg (rounded to the nearest 50 mg or 100 mg) up to a maximum of 900 mg once weekly for 12 weeks for adults and children 12 years and older, and 25 mg/kg (rounded to the nearest 50 mg or 100 mg) up to a maximum of 900 mg once weekly for 12 weeks for children 2 to 11 years.

The treatment for Latent Tuberculosis (TB) infection is PRIFTIN (rifapentine) in combination with isoniazid for 12 weeks, with doses based on the patient's weight, as a once-weekly regimen 2.

• Key points:
  • PRIFTIN must be used in combination with isoniazid.
  • The treatment duration is 12 weeks.
  • Doses are based on the patient's weight.
  • The regimen is once-weekly.
• Dosing:
  • PRIFTIN: up to a maximum of 900 mg once weekly.
  • Isoniazid: 15 mg/kg (up to 900 mg) for adults and children 12 years and older, and 25 mg/kg (up to 900 mg) for children 2 to 11 years. 2

From the Research

Treatment Options for Latent Tuberculosis (TB) Infection

The treatment for Latent Tuberculosis (TB) infection includes several options, each with its own efficacy and safety profile. The main treatment options are:

• Isoniazid (INH) monotherapy for 9 months, which has an efficacy of more than 90% if completed properly 3
• 2 months of rifampin and pyrazinamide, which has excellent efficacy in experimental studies in mice and randomized trials, largely in HIV-infected persons, but is associated with an unacceptably high rate of severe liver toxicity in non-HIV-infected adults 3
• 3 to 4 months of INH and rifampin, which has equivalent effectiveness as 6 months INH in several randomized trials 3
• 4 months of rifampin monotherapy, which has been found to have significantly better completion than 9 months of INH, with significantly less toxicity, especially hepatotoxicity 3
• 3 months of isoniazid plus rifapentine once-weekly regimen, which has been demonstrated to be as effective as 9 months of isoniazid alone in preventing tuberculosis, with a higher treatment-completion rate and lower rates of hepatotoxicity 4

Adverse Events and Safety Profile

The safety profile of these treatment options varies, with INH monotherapy associated with hepatotoxicity, and rifampin and pyrazinamide associated with severe liver toxicity in non-HIV-infected adults. The 3 months of isoniazid plus rifapentine once-weekly regimen has been found to have a favorable adverse event profile, with lower rates of hepatotoxicity compared to INH monotherapy 5, 4.

Clinical Efficacy and Recommendations

The clinical efficacy of these treatment options has been established, with the 9 months of INH monotherapy having an estimated protective effect of 60%-90%. The 3 months of isoniazid plus rifampin regimen has been found to be equivalent to 6 months of INH in terms of efficacy and safety, and is recommended in guidelines from the National Institute for Health and Care Excellence (NICE) and the World Health Organization (WHO) 6. The 3 months of isoniazid plus rifapentine once-weekly regimen has also been demonstrated to be effective in preventing tuberculosis, and is a promising option for the treatment of latent TB infection 4, 7.