What is the recommended dosage and treatment regimen for Bictegravir (Biktarvy) for HIV-1 infection?

Bictegravir (Biktarvy) Dosage and Treatment Regimen for HIV-1 Infection

Biktarvy (bictegravir/tenofovir alafenamide/emtricitabine) is recommended as a complete single-tablet regimen for HIV-1 infection at a dosage of 50 mg bictegravir, 200 mg emtricitabine, and 25 mg tenofovir alafenamide taken once daily with or without food in adults and pediatric patients weighing at least 25 kg. 1

Standard Dosing Recommendations

Adults and Adolescents (≥25 kg)

• One tablet containing 50 mg bictegravir, 200 mg emtricitabine, and 25 mg tenofovir alafenamide once daily
• Can be taken with or without food
• Requires estimated creatinine clearance ≥30 mL/min 1

Children (14 kg to <25 kg)

• One tablet containing 30 mg bictegravir, 120 mg emtricitabine, and 15 mg tenofovir alafenamide once daily
• Can be taken with or without food
• Requires estimated creatinine clearance ≥30 mL/min 1, 2

Patient Selection and Indications

Biktarvy is indicated for:

• Treatment-naïve patients (no prior antiretroviral therapy)
• Virologically suppressed patients (HIV-1 RNA <50 copies/mL) switching from another stable regimen
• Patients with no known or suspected resistance to bictegravir, emtricitabine, or tenofovir 1

Clinical Efficacy and Evidence

Biktarvy has demonstrated high efficacy in multiple clinical trials:

• Noninferior to dolutegravir-based regimens in treatment-naïve adults through 96 weeks 3
• Maintains virological suppression when switching from other regimens, including in patients with preexisting NRTI resistance 4
• High barrier to resistance with no treatment-emergent resistance observed in clinical trials 3, 4
• Effective in children and adolescents with sustained virological suppression 5, 2

Testing Requirements Before Initiation

Prior to starting Biktarvy:

• Test for hepatitis B virus (HBV) infection
• Assess renal function (serum creatinine, estimated creatinine clearance)
• Evaluate urine glucose and protein
• No HLA-B*5701 testing required (advantage over abacavir-containing regimens) 1, 6

Special Populations and Considerations

Renal Impairment

• Not recommended for patients with severe renal impairment (CrCl 15-<30 mL/min)
• Not recommended for patients with end-stage renal disease (ESRD) who are not receiving chronic hemodialysis
• Can be used in virologically-suppressed adults with ESRD on chronic hemodialysis (administer after dialysis) 1

Hepatic Impairment

• Not recommended in patients with severe hepatic impairment (Child-Pugh Class C) 1

Pregnancy

• Can be used in pregnant individuals who are virologically suppressed
• Requires close viral load monitoring due to lower drug exposures during pregnancy 1

HBV Co-infection

• Appropriate for patients with HIV/HBV co-infection as it contains tenofovir alafenamide and emtricitabine, which are active against HBV
• Severe acute exacerbations of hepatitis B can occur upon discontinuation; monitor hepatic function for several months after stopping 1, 7

Monitoring During Treatment

• Viral load: Check 1 month after starting treatment, then every 3-4 months until viral suppression
• Once suppressed: Monitor every 6 months
• Renal function: Assess serum creatinine, estimated creatinine clearance, urine glucose and protein
• In patients with chronic kidney disease: Also monitor serum phosphorus 6, 1

Advantages of Biktarvy

• Single-tablet, once-daily regimen (high convenience)
• Can be taken with or without food
• Low risk of resistance with virologic failure
• Relatively few drug interactions
• No HLA-B*5701 testing required (unlike abacavir-containing regimens)
• Suitable for patients with HBV co-infection 8, 7

Limitations and Precautions

• Cannot be used with rifampin (significant drug interaction)
• May increase serum creatinine by approximately 0.1 mg/dL through inhibition of tubular secretion (not reflecting actual kidney function decline)
• Not recommended for patients with severe hepatic impairment
• Not recommended for patients with severe renal impairment unless on hemodialysis 8, 1

Common Adverse Events

• Diarrhea (reported in approximately 18% of patients)
• Headache (reported in approximately 16% of patients)
• Nausea
• Fatigue
• Abnormal dreams 3

Biktarvy represents an important single-tablet regimen for HIV treatment with high efficacy, good tolerability, and a high barrier to resistance, making it suitable for both initial therapy and for patients switching from other regimens.