What is the treatment for Latent Tuberculosis (TB)?

From the Guidelines

The treatment for Latent Tuberculosis (TB) should be a 3-month course of once-weekly isoniazid 900mg plus rifapentine 900mg, as it is the preferred regimen due to its effectiveness, safety, and high treatment completion rates. This recommendation is based on the guidelines for the treatment of latent tuberculosis infection published in 2020 by the National Tuberculosis Controllers Association and CDC 1. The guidelines suggest that short-course (3- to 4-month) rifamycin-based treatment regimens are preferred over longer-course (6–9 month) isoniazid monotherapy for treatment of LTBI.

Some key points to consider when treating LTBI include:

• Ruling out active TB through symptom screening, chest X-ray, and sometimes sputum testing before starting treatment
• Baseline liver function tests are recommended, especially for those with risk factors for hepatotoxicity
• Patients should be monitored for side effects during treatment, particularly hepatitis symptoms (nausea, vomiting, abdominal pain, jaundice)
• Vitamin B6 (pyridoxine, 25-50mg daily) is often given with isoniazid to prevent peripheral neuropathy
• Treatment completion is essential as partial treatment may not provide adequate protection against developing active TB disease

Alternative treatment options include:

• 4 months of daily rifampin (10mg/kg, maximum 600mg)
• 3 months of daily isoniazid (5mg/kg, maximum 300mg) plus rifampin
• 9-month course of daily isoniazid (5mg/kg, maximum 300mg), although this is less commonly used due to its longer duration 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 treatment for Latent Tuberculosis (TB) is PRIFTIN (rifapentine) in combination with isoniazid for 12 weeks, administered once weekly as directly observed therapy.

• The recommended dose of PRIFTIN is based on the patient's weight, 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 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 children 2 to 11 years. 2 2 2

From the Research

Treatment Options for Latent Tuberculosis (TB)

The treatment for Latent Tuberculosis (TB) includes several options, as outlined below:

• 9 months of isoniazid (INH) alone, which has an efficacy of more than 90% if completed properly 3
• 3 months of rifapentine and isoniazid, which has been shown to be as effective as 9 months of isoniazid alone in preventing tuberculosis, with a higher treatment-completion rate 4
• 4 months of rifampin, which has been found to have significantly better completion rates and less toxicity than 9 months of INH 3
• 3 to 4 months of INH and rifampin, which has been shown to have equivalent effectiveness to 6 months of INH 3
• Once-weekly isoniazid and rifapentine for 12 weeks, which has been shown to be safe and effective compared to 9 months of isoniazid 5

Adverse Events Associated with Treatment

The adverse event profiles of these treatment options vary:

• INH monotherapy is associated with hepatotoxicity and low compliance 4, 3
• Rifapentine and isoniazid combination therapy has a lower frequency of hepatotoxicity, but may cause flu-like reactions 6
• Rifampin monotherapy has been associated with an unacceptably high rate of severe liver toxicity in non-HIV-infected adults 3

Recommendations and Guidelines

Various guidelines and recommendations have been made for the treatment of Latent TB:

• The World Health Organization recommends a regimen of 12 doses of isoniazid and rifapentine given once weekly (INH/RPT-3) for the treatment of LTBI 6
• The National Institute for Health and Care Excellence (NICE) recommends that close contacts of individuals with active pulmonary or laryngeal TB undergo LTBI treatment, with various regimens available 7
• The Centers for Disease Control and Prevention (CDC) recommends treatment for LTBI, with options including 9 months of INH, 4 months of rifampin, and 3 months of INH and rifapentine 7, 5