What is the recommended treatment for latent tuberculosis (TB) in a person living with Human Immunodeficiency Virus (HIV) on Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide)?

Treatment of Latent TB Infection in Persons Living with HIV on Biktarvy

For persons living with HIV on Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide), a 9-month regimen of daily isoniazid is the recommended treatment for latent tuberculosis infection.

Preferred Treatment Options

Primary Recommendation

• 9 months of daily isoniazid (300 mg for adults) with pyridoxine (vitamin B6) supplementation 1, 2
  • This regimen should consist of at least 270 doses administered over 9 months (up to 12 months if interruptions occur) 1
  • Strong recommendation for HIV-positive individuals (A.II evidence level) 1

Alternative Options (if isoniazid cannot be tolerated)

1. 3 months of once-weekly isoniazid plus rifapentine (preferred shorter regimen) 1

   • Note: This regimen requires directly observed therapy (DOT)
   • Caution: Potential drug interactions with Biktarvy must be carefully evaluated

2. 3 months of daily isoniazid plus rifampin 1, 2

   • Caution: Significant drug interactions with bictegravir component of Biktarvy

Drug Interaction Considerations

Biktarvy and Rifamycins

• Rifampin-containing regimens are contraindicated with Biktarvy due to significant drug interactions with the bictegravir component 1
• If a rifamycin is deemed necessary, rifabutin may be substituted for rifampin in some cases, but requires careful dose adjustment and monitoring 1
• The 2-month rifampin/pyrazinamide regimen that would normally be preferred in HIV patients not on antiretrovirals cannot be used with Biktarvy 1

Monitoring Requirements

Clinical Monitoring

• Monthly clinical evaluations to assess:
  • Medication adherence
  • Potential side effects (particularly hepatotoxicity)
  • Signs and symptoms of active TB 1, 2

Laboratory Monitoring

• Baseline laboratory testing is recommended for:
  • HIV-infected persons
  • Those with suspected liver disorders
  • Pregnant women
  • Persons with history of chronic liver disease
  • Regular alcohol users 1, 2

Adverse Effects Management

• Patients should be educated about potential side effects, particularly:
  • Hepatotoxicity (yellowing of skin/eyes, abdominal pain, nausea)
  • Peripheral neuropathy (can be mitigated with pyridoxine)
  • Rash or fever 1, 2
• Instruct patients to stop treatment and seek immediate medical evaluation if significant side effects occur 1

Treatment Completion

• Completion is based on the total number of doses administered, not just duration 1
• For daily isoniazid: 270 doses over 9 months 1
• For twice-weekly isoniazid (if used with DOT): 76 doses over 9 months 1

Special Considerations

Adherence Support

• Consider directly observed therapy (DOT) for patients with adherence concerns 1
• Monthly follow-up visits are essential for monitoring adherence and side effects 1, 2

Common Pitfalls to Avoid

1. Failing to rule out active TB before starting treatment

   • Active TB must be excluded through history, physical exam, chest radiography, and when indicated, bacteriologic studies 1
   • Treating active TB with a single drug can lead to drug resistance

2. Overlooking drug interactions

   • Rifampin and rifapentine have significant interactions with Biktarvy
   • Always check for drug-drug interactions before prescribing

3. Inadequate monitoring

   • Poor monitoring can lead to undetected adverse effects and reduced adherence
   • Monthly clinical evaluations are essential 1, 2

4. Insufficient treatment duration

   • Shorter regimens (6 months of isoniazid) provide less protection for HIV-positive individuals 1
   • Ensure completion of the full 9-month course (270 doses) 1

The evidence strongly supports that treating LTBI in persons living with HIV significantly reduces the risk of progression to active TB disease 3, 4. While shorter regimens may offer better adherence 5, the drug interaction concerns with Biktarvy make the 9-month isoniazid regimen the safest and most effective option for this specific patient population.