BIKTARVY Dosage & Rx Info | Uses, Side Effects

Biktarvy Generic Name & Formulations

Legal Class

General Description

Bictegravir, emtricitabine, tenofovir alafenamide; 30mg/120mg/15mg, 50mg/200mg/25mg; tabs.

Pharmacological Class

HIV-1 integrase strand transfer inhibitor (INSTI) + nucleoside analog reverse transcriptase inhibitors (NRTIs).

How Supplied

Tabs (30mg/120mg/15mg, 50mg/200mg/25mg)—30; Blister packs (50mg/200mg/25mg)—30

Storage

Store bottles below 30 °C (86 °F).

Store blister packs at 25 °C (77 °F), excursions permitted to 15–30 °C (59–86 °F).

Manufacturer

Gilead Sciences, Inc.

Generic Availability

Mechanism of Action

Bictegravir, an integrase strand transfer inhibitor, prevents the integration of linear HIV-1 DNA into host genomic DNA, thereby blocking the formation and propagation of the HIV-1 provirus. Emtricitabine competes with the natural substrate deoxycytidine 5'-triphosphate and gets incorporated into nascent viral DNA, thereby inhibiting the activity of HIV-1 reverse transcriptase which results in chain termination. Tenofovir alafenamide, a prodrug of tenofovir, gets phosphorylated to the active metabolite tenofovir diphosphate which inhibits HIV-1 replication through incorporation into viral DNA by the HIV reverse transcriptase, resulting in DNA chain-termination.

Biktarvy Indications

Indications

As a complete regimen for HIV-1 infection in patients with no antiretroviral treatment history or to replace the current antiretroviral regimen in those who are virologically-suppressed (HIV-1 RNA <50 copies/mL) on a stable antiretroviral with no known or suspected substitutions associated with resistance to bictegravir or tenofovir.

Biktarvy Dosage and Administration

Adults and Children

<14kg: not established. Test for HBV infection prior to initiation. 14kg–<25kg (CrCl ≥30mL/min): 1 tab (30mg/120mg/15mg) once daily. For children unable to swallow: may split tab and each part taken separately, but all must be ingested within ~10mins. ≥25kg (CrCl ≥30mL/min), virologically-suppressed adults on hemodialysis (CrCL <15mL/min), or virologically-suppressed pregnant individuals (monitor closely): 1 tab (50mg/200mg/25mg) once daily.

Biktarvy Contraindications

Contraindications

Concomitant dofetilide, rifampin.

Biktarvy Boxed Warnings

Boxed Warning

Post-treatment acute exacerbation of hepatitis B.

Biktarvy Warnings/Precautions

Warnings/Precautions

Test for HBV before starting therapy and closely monitor patients co-infected with HBV and HIV for several months after stopping treatment (discontinuing therapy may exacerbate HBV infection); if appropriate, anti-hepatitis B therapy may be warranted (esp. in those with advanced liver disease or cirrhosis). Suspend therapy if lactic acidosis or pronounced hepatotoxicity (eg, hepatomegaly, steatosis) occurs. Monitor serum creatinine, CrCl, urine glucose, urine protein, and serum phosphorus (in chronic kidney disease); discontinue if significant renal dysfunction or Fanconi syndrome occurs. Severe renal impairment (CrCl <30mL/min), ESRD (CrCl <15mL/min) not receiving chronic dialysis, or ESRD with no antiretroviral treatment history and receiving chronic dialysis: not recommended. Severe hepatic impairment (Child-Pugh Class C): not recommended. Pregnancy: see full labeling. Nursing mothers.

Biktarvy Pharmacokinetics

Metabolism

Bictegravir: CYP3A, UGT1A1. Tenofovir alafenamide: cathepsin A, peripheral blood mononuclear cells, carboxylesterase 1 (hepatocytes).

Elimination

Bictegravir: renal (35%), fecal (60.3%); half-life: 17.3 hours (range: 14.8–20.7). Emtricitabine: renal (70%), fecal (13.7%); half-life: 10.4 hours (range: 9.0–12.0). Tenofovir alafenamide: renal (<1%), fecal (31.7%); half-life: 0.51 hours (range: 0.45–0.62).

Biktarvy Interactions

Interactions

See Contraindications. Concomitant other antiretrovirals: not recommended. May potentiate concomitant OCT2 and MATE1 substrates (eg, dofetilide). May be affected by drugs that induce or inhibit CYP3A and UGT1A1. Concomitant drugs that strongly affect P-gp and BCRP activity may lead to changes in TAF absorption. May be potentiated by drugs that decrease renal function or compete for active tubular secretion (eg, acyclovir, cidofovir, ganciclovir, valacyclovir, valganciclovir, aminoglycosides, NSAIDs). May be antagonized by anticonvulsants (eg, carbamazepine, oxcarbazepine, phenobarbital, phenytoin); consider alternatives. Concomitant rifabutin, rifapentine, St. John's wort: not recommended. Concomitant antacids (containing Al/Mg): give Biktarvy at least 2hrs before or 6hrs after. Concomitant oral iron/calcium supplements or antacids: can take together with food. Routine coadministration (under fasting conditions) with, or 2hrs after, oral iron/calcium supplements or antacids: not recommended. May potentiate metformin (refer to metformin labeling).

Biktarvy Adverse Reactions

Adverse Reactions

Diarrhea, nausea, headache; HBV exacerbation, new onset or worsening renal impairment, immune reconstitution syndrome, lactic acidosis, hepatomegaly.

Biktarvy Clinical Trials

See Literature

Biktarvy Note

Notes

Biktarvy Patient Counseling