Can an HIV patient be switched from Odefsey (emtricitabine, rilpivirine, and tenofovir disoproxil fumarate) to Biktarvy (bictegravir, emtricitabine, and tenofovir alafenamide)?

Switching from Odefsey to Biktarvy in HIV Patients

Yes, switching from Odefsey (emtricitabine/rilpivirine/tenofovir disoproxil fumarate) to Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide) is appropriate and recommended for virologically suppressed HIV patients, offering improved renal and bone safety, higher resistance barrier, and simplified management. 1

Key Requirements Before Switching

Before making any treatment switch, you must review the patient's complete antiretroviral treatment history, prior resistance testing results, comorbidities, potential drug-drug interactions, and hepatitis B coinfection status. 2

Critical Pre-Switch Assessments

• Confirm virologic suppression (HIV-1 RNA <50 copies/mL) on current Odefsey regimen 1
• Review resistance history to ensure no documented or suspected resistance to bictegravir or tenofovir 1
• Test for hepatitis B if not previously done, as both regimens contain agents active against HBV 1
• Assess renal function including serum creatinine, estimated creatinine clearance, urine glucose, and urine protein 1
• Evaluate bone health in patients with osteopenia/osteoporosis risk, as TAF offers superior bone safety compared to TDF 2

Why This Switch Makes Clinical Sense

Superior Resistance Barrier

Biktarvy provides a significantly higher genetic barrier to resistance compared to Odefsey. Rilpivirine (in Odefsey) is a low-barrier NNRTI, while bictegravir is a second-generation integrase inhibitor with high resilience to resistance mutations. 2, 3

• Switching from a low-barrier regimen (rilpivirine) to a high-barrier regimen (bictegravir) is generally safe even without complete resistance history 2
• No treatment-emergent resistance to bictegravir has been detected in clinical trials through 5 years of follow-up 4

Improved Safety Profile

The switch from TDF (in Odefsey) to TAF (in Biktarvy) offers superior renal and bone safety based on consistent surrogate marker data. 2

• TAF demonstrates better bone mineral density preservation and reduced renal toxicity markers compared to TDF 2
• This switch is particularly recommended for patients at high risk of renal or bone toxicity 2
• The only trade-off is modest lipid elevations due to loss of TDF's lipid-lowering effects 2

Elimination of Drug-Drug Interactions

A critical advantage of switching to Biktarvy is the elimination of rilpivirine's problematic drug interactions with acid-reducing agents. 5

• Rilpivirine requires acidic environment for absorption and cannot be used with proton pump inhibitors 5
• Bictegravir has minimal drug interactions and can be used with PPIs, allowing better management of gastrointestinal symptoms 5

Switching Protocol

The Switch Process

For virologically suppressed patients, the switch can be made directly without overlap or lead-in period. 2

1. Discontinue Odefsey and start Biktarvy the following day
2. Dosing: One tablet of Biktarvy (50 mg bictegravir/200 mg emtricitabine/25 mg TAF) once daily with or without food 1
3. No oral lead-in required as this is a switch between oral regimens 6

Post-Switch Monitoring

Check HIV-1 RNA at 1 month after switching to ensure continued virologic suppression. 2

• Viral load assessment at 1 month post-switch is mandatory 2
• Continue monitoring every 3 months for the first year 7
• Monitor renal function and bone health as clinically appropriate 1
• Assess lipid profile given expected modest increases with TAF 2

Special Populations

Hepatitis B Coinfection

Both regimens contain agents active against HBV (emtricitabine and tenofovir), making this switch safe for HBV-coinfected patients. 8, 1

• Continue monitoring hepatic function closely 1
• Ensure no interruption in HBV-active therapy during the switch 1

Renal Impairment

Biktarvy is not recommended if estimated creatinine clearance is 15 to <30 mL/min, or <15 mL/min in patients not on chronic hemodialysis. 1

• For patients with eGFR 15-30 mL/min, consider alternative regimens 1
• For stable patients on hemodialysis with eGFR <15 mL/min who are virologically suppressed, Biktarvy can be used 1

Pregnancy

For pregnant individuals who are virologically suppressed on Odefsey, switching to Biktarvy can be considered, though data are more limited. 1

• Biktarvy is approved for use in pregnant individuals who are virologically suppressed with no known resistance 1

Common Pitfalls to Avoid

Resistance Considerations

Never switch from a high-barrier regimen to a low-barrier regimen without reviewing resistance history. However, switching from the low-barrier rilpivirine to high-barrier bictegravir is safe. 2

• If switching in the opposite direction (Biktarvy to Odefsey), resistance history would be critical 2
• The current switch direction (Odefsey to Biktarvy) is inherently safer due to improved resistance barrier 2

Drug Interactions

Review all concomitant medications before switching, as bictegravir has different interaction profiles than rilpivirine. 1

• Biktarvy is contraindicated with dofetilide and rifampin 1
• Unlike rilpivirine, bictegravir can be used with acid-reducing agents 5

Weight Considerations

Counsel patients about potential weight gain, which has been observed with integrase inhibitor-based regimens including Biktarvy. 9

• Median weight gain of +6.1 kg was observed at 5 years in clinical trials 4
• Weight changes appear similar whether switching from other regimens or starting de novo 9

Evidence Supporting This Switch

High-quality clinical trial data demonstrate that switching to Biktarvy from other regimens maintains virologic suppression with excellent safety. 6, 9

• In a randomized controlled trial, switching to B/F/TAF from dolutegravir-based regimens maintained 99% virologic suppression at 96 weeks 9
• Another study showed 98.6% maintained HIV-1 RNA <50 copies/mL through 5 years of B/F/TAF treatment 4
• Switching studies included patients with preexisting NRTI resistance without compromising efficacy 6

The 2018 International Antiviral Society-USA guidelines explicitly support switching from TDF-based regimens to TAF-based regimens for improved safety, and Biktarvy is listed as a generally recommended initial regimen. 2