Drug interactions of Biktarvy

1. Other Antiretroviral Drugs

Since Biktarvy is a complete regimen, co-administration with other antiretroviral drugs used for the treatment of HIV-1 infection is not recommended.

2. Potential of Biktarvy to Affect Other Drugs

Bictegravir inhibits organic cation transporter 2 (OCT2) and multidrug and toxin extrusion protein 1 (MATE1) in vitro. Co-administration of Biktarvy with drugs that are substrates of these transporters may increase their plasma concentrations.

3. Potential of Other Drugs to Affect One or More Components of Biktarvy

Bictegravir is a substrate of CYP3A and UGT1A1. Drugs that are both strong CYP3A inducers and UGT1A1 inducers can significantly reduce the plasma concentration of bictegravir, which may lead to loss of therapeutic effect of Biktarvy and development of drug resistance.

Concomitant use with drugs that are both strong CYP3A inhibitors and UGT1A1 inhibitors may significantly increase the plasma concentration of bictegravir.

Tenofovir alafenamide is a substrate of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP). Co-administration with drugs that inhibit P-gp and BCRP may increase the absorption and plasma concentration of tenofovir alafenamide. Concomitant use with drugs that induce P-gp activity is expected to decrease the absorption of tenofovir alafenamide, leading to reduced plasma concentration, which may result in loss of therapeutic effect of Biktarvy and development of drug resistance.

4. Drugs Affecting Renal Function

Since emtricitabine and tenofovir are excreted primarily through a combination of glomerular filtration and active tubular secretion in the kidneys, co-administration of Biktarvy with drugs that reduce renal function or compete for active tubular secretion may increase the concentrations of emtricitabine, tenofovir, and other renally excreted drugs, thereby potentially increasing the risk of adverse reactions.

5. Established and Potentially Significant Drug Interactions

A list of established or potentially clinically significant drug interactions and recommended prevention or management strategies is provided.

Antiarrhythmics: Dofetilide: Concomitant administration is contraindicated.

Anticonvulsants: Carbamazepine, oxcarbazepine, phenobarbital, phenytoin: Consider using alternative anticonvulsants.

Antimycobacterials: Rifabutin, rifampin, rifapentine: Concomitant administration with rifampin is contraindicated. Concomitant administration with rifabutin or rifapentine is not recommended.

Herbal Products: St. John’s Wort (Hypericum perforatum): Concomitant administration is not recommended.

Oral Drugs or Supplements Containing Polyvalent Cations:

Antacids containing aluminum/magnesium: Biktarvy should be taken at least 2 hours before or 6 hours after taking antacids containing aluminum/magnesium. Routine co-administration with or within 2 hours after taking aluminum/magnesium-containing antacids is not recommended.

Supplements or antacids containing calcium or iron: Biktarvy can be taken with meals concurrently with supplements or antacids containing calcium or iron. Routine co-administration on an empty stomach or within 2 hours after taking calcium- or iron-containing supplements or antacids is not recommended.

For pregnant patients:

Antacids containing aluminum/magnesium: Biktarvy should be taken at least 2 hours before or 6 hours after taking aluminum/magnesium-containing antacids, regardless of food intake.

Supplements or antacids containing calcium or iron: Biktarvy can be taken with meals concurrently with supplements or antacids containing calcium or iron; however, when taken on an empty stomach, Biktarvy should be taken at least 2 hours before or 6 hours after taking calcium- or iron-containing supplements or antacids.

Metformin: Refer to the metformin prescribing information to assess the benefits and risks of concomitant use with Biktarvy.

6. Drugs with No Clinically Significant Interactions with Biktarvy

Based on drug interaction studies with Biktarvy or its components, no clinically significant drug interactions were observed when Biktarvy was co-administered with the following drugs: ethinyl estradiol, ledipasvir/sofosbuvir, midazolam, norethindrone, sertraline, sofosbuvir, sofosbuvir/velpatasvir, sofosbuvir/velpatasvir/voxilaprevir.

FDA，2025.07