https://interactions.guidetherapeutiquevih.com/en/interaction-details?id=21063

Bictegravir

Calcium (supplements)

Administration time adjustment is recommended.

No pharmaceutical opinion available for this interaction.

Mechanism

Cations by chelation may reduce the absorption of Bictegravir.

Bictegravir

Pharmacodynamic effects

Possible decrease of clinical efficacy.

Recommendations

If bictegravir taken with food : it may be taken with calcium without spacing dose.

If bictegravir taken fasting : it must be taken ideally 2 hours before or 2 hours after taking calcium.

Monitor for clinical efficacy.

Alternative solution(s)

–

Calcium (supplements)

Pharmacodynamic effects

–

Recommendations

–

Alternative solution(s)

–

Monitor

–

Tests

Bictegravir plasma level

CD4+

Viral load HIV

Pharmacokinetic parameters
Parameters
Reference number
# patients
HIV
Dose
Frequency
AUC
Cmax
Bictegravir
3467 3467
14 14
- -
50 mg 50 mg
x 1 x 1
- 33% + 3%
- 42% - 10%
Calcium (supplements)
3467 3467
14 14
- -
1200 mg * 1200 mg †
x 1 * x 1 †
   
   
Comment

Ref #3467 : * Simultaneous administration with bictegravir, fasted.
† Simultaneous administration with bictegravir, fed.

Ref #3715 : In a study of 33 HIV-positive pregnant women receiving B/F/TAF, only one patient had bictegravir levels below the protein-adjusted 95% effective concentration. This patient took calcium and iron supplements during pregnancy. Despite everything, she had an undetectable viral load, like all the other patients, throughout the pregnancy.

Comment
Reference
  • 3392
    Bictegravir/emtricitabine/tenofovir alafenamide (BIKTARVY), Gilead Sciences, Ontario, Canada, 14 avril 2023.
  • 3467
    Mathias A, Lutz J, West S, Xiao D, Chuck S et al. Pharmacokinetics (PK) of bictegravir (BIC) in combination with polyvalent cation containing (PVCC) antacids and supplements. HIV Drug Therapy, Glasgow, Scotland, 28-31 oct 2018, Abstract P206.
  • 3715
    Zhang H, Hindman JT, Lin L, Davis M, Shang, J et al. A study of the pharmacokinetics, safety, and efficacy of bictegravir/emtricitabine/tenofovir alafenamide in virologically suppressed pregnant women with HIV. AIDS. 2024 Jan 1; 38(1): F1-F9.