Biktarvy for HIV-1 treatment in adults and children weighing at least 14 kg

Biktarvy is a single-tablet regimen combining three antiretroviral agents used to treat HIV-1 infection. It is approved for use in adults and pediatric patients weighing at least 14 kilograms. Biktarvy works as a complete regimen for both treatment-naïve patients and those already on a stable antiretroviral regimen without resistance to its components.

Biktarvy is indicated for the treatment of human immunodeficiency virus type 1 (HIV-1) infection in adults and pediatric patients weighing at least 14 kg:

• Patients with no prior antiretroviral treatment history.
• Patients with prior treatment experience who are not virologically suppressed and have no known or suspected resistance to integrase strand transfer inhibitors, emtricitabine, or tenofovir.
• Virologically suppressed patients (HIV-1 RNA less than 50 copies/mL) on a stable regimen with no known or suspected resistance to bictegravir or tenofovir, to replace their current regimen.

bictegravir sodium, emtricitabine, and tenofovir alafenamide fumarate

Biktarvy combines three active drugs:

• Bictegravir: an integrase strand transfer inhibitor (INSTI) that blocks the HIV enzyme integrase, preventing viral DNA from integrating into human DNA.
• Emtricitabine and Tenofovir alafenamide (TAF): nucleoside reverse transcriptase inhibitors (NRTIs) that interfere with viral replication by inhibiting reverse transcriptase, an enzyme HIV uses to duplicate its genetic material.

Together, these agents inhibit HIV replication at multiple stages, reducing viral load in the body.

Recommended dosages

• Adults and pediatric patients ≥25 kg: One tablet containing 50 mg bictegravir, 200 mg emtricitabine, and 25 mg tenofovir alafenamide once daily, with or without food.
• Pediatric patients 14 to One tablet containing 30 mg bictegravir, 120 mg emtricitabine, and 15 mg tenofovir alafenamide once daily, with or without food. Tablets may be split for children unable to swallow whole tablets, with all parts taken within approximately 10 minutes.
• Pregnant individuals (virologically suppressed): One tablet of 50 mg/200 mg/25 mg once daily, with or without food. Viral load should be monitored closely during pregnancy due to lower drug exposures.

Monitoring and testing

• Test for hepatitis B virus infection before or when initiating therapy.
• Assess serum creatinine, estimated creatinine clearance, urine glucose, and urine protein prior to and during treatment.
• For patients with chronic kidney disease, also assess serum phosphorus.

Use restrictions

• Not recommended for patients with severe renal impairment (estimated creatinine clearance 15 to below 30 mL/min) or end-stage renal disease (below 15 mL/min) who are not on chronic hemodialysis, or those with no antiretroviral history on hemodialysis.
• Not recommended for patients with severe hepatic impairment (Child-Pugh Class C).

Special instructions

• For adults on chronic hemodialysis with creatinine clearance below 15 mL/min, take the daily dose after dialysis on dialysis days.

• Co-administration with dofetilide.
• Co-administration with rifampin.

Severe acute exacerbation of hepatitis B

Discontinuation of Biktarvy in patients co-infected with HIV-1 and hepatitis B virus (HBV) may cause severe acute hepatitis B exacerbations, including liver failure. Hepatic function should be closely monitored with clinical and laboratory follow-up for several months after stopping treatment. Anti-hepatitis B therapy may be needed, especially in those with advanced liver disease.

Drug interactions

Co-administration with certain drugs can cause loss of Biktarvy’s effectiveness or increase adverse reactions. Biktarvy is contraindicated with dofetilide and rifampin due to serious interaction risks. Review all concomitant medications before and during therapy.

Immune reconstitution syndrome

May occur during initial treatment as the immune system recovers, causing inflammatory responses to infections. Autoimmune disorders have also been reported.

Renal impairment

New or worsening kidney problems, including Fanconi syndrome, have been reported. Assess renal function before and during therapy, and discontinue Biktarvy if clinically significant kidney issues develop.

Lactic acidosis and severe hepatomegaly with steatosis

Rare but serious risks include lactic acidosis and pronounced liver enlargement with fat accumulation. Discontinue treatment if these are suspected.

Common side effects (≥5%)

• Diarrhea
• Nausea
• Headache

Other reported side effects <5%

• Fatigue
• Abnormal dreams
• Dizziness
• Insomnia
• Abdominal distension
• Vomiting
• Flatulence
• Dyspepsia
• Abdominal pain
• Rash
• Depression

Suicidal ideation, attempts, and depression occurred primarily in patients with prior psychiatric history.

The majority of adverse events were mild (Grade 1).

Contraindicated with:

• Dofetilide due to risk of increased dofetilide levels causing serious or life-threatening events.
• Rifampin due to decreased bictegravir levels, risking loss of therapeutic effect and resistance development.

Other drug interactions may lead to loss of effect or increased adverse effects. Careful medication review and monitoring for interactions are advised during Biktarvy therapy.

Pregnancy

Biktarvy is recommended for use in pregnant individuals who are virologically suppressed on a stable regimen with no known resistance to its components. Lower drug exposures have been observed during pregnancy, so viral load should be monitored closely.

Hepatitis B

Patients co-infected with HIV and HBV require careful monitoring if Biktarvy is stopped to prevent severe hepatitis B exacerbations.