https://interactions.guidetherapeutiquevih.com/en/interaction-details?id=18984

Bictegravir

Rifampin

Contraindicated.

No pharmaceutical opinion available for this interaction.

Mechanism

Rifampin may induce the metabolism (UGT 1A1 and CYP3A) and decrease the plasma concentration of Bictegravir.

Bictegravir

Pharmacodynamic effects

Possible decrease of clinical efficacy.

Recommendations

Avoid association. Choose an alternative.

Alternative solution(s)

Patients without resistance to integrase inhibitors : dolutegravir 50 mg BID or raltegravir 800 mg BID.

Rifampin

Pharmacodynamic effects

–

Recommendations

–

Alternative solution(s)

Patients without resistance to integrase inhibitors : see rifabutine + dolutegravir or raltegravir.

Monitor

–

Tests

–

Pharmacokinetic parameters
Parameters
Reference number
# patients
HIV
Dose
Frequency
AUC
Cmax
Bictegravir
3337 3440
15 26
- -
75 mg * 50 mg †
x 1 BID
- 75% - 61%
- 28% - 47%
Rifampin
3337 3440
15 26
- -
600 mg 600 mg
QD QD
   
   
Comment

Ref #3337 : * Fed.

Ref #3440 : † Administered as a fixed-dose tablet also containing emtricitabine 200mg and tenofovir alafenamide 25mg.
° Compared to standard once daily administration.
Despite the increased frequency of administration, the pharmacokinetic interaction is not counteracted.

Reference
  • 3337
    Zhang H, Custodio JM, Wei X, Wang H, Vu A, et al. Clinical Pharmacology of the HIV Integrase Strand Transfer Inhibitor Bictegravir. CROI 2017, Seattle, WA USA, February 13-16 2017. Abstract #40.
  • 3392
    Bictegravir/emtricitabine/tenofovir alafenamide (BIKTARVY), Gilead Sciences, Ontario, Canada, 28 février 2020.
  • 3440
    Custodio JM, West SK, Collins S et al. Pharmacokinetics of bictegravir administered twice daily in combination with rifampin. CROI 2018, Boston, MA USA, March 4–7, 2018. Abstract #34.