Elvitegravir with cobicistat, emtricitabine and tenofovir alafenamide

How it works

Elvitegravir inhibits HIV integrase to block insertion of viral DNA into the host genome and is boosted by cobicistat's inhibition of CYP3A; emtricitabine and tenofovir alafenamide cause chain termination during reverse transcription.

Prescribing in practice

• Cobicistat is a potent CYP3A inhibitor producing numerous serious interactions, so review all co-medications including statins, sedatives, ergot derivatives and steroids before prescribing.
• Elvitegravir requires food and adequate gastric acidity, so it must be taken with a meal and separated in time from antacids and cation-containing supplements that chelate it.
• Cobicistat inhibits tubular creatinine secretion, causing a small early creatinine rise that does not reflect true loss of renal function.

Monitoring

Monitor HIV viral load and CD4 count alongside renal function, liver function and lipids during therapy.

Counselling the patient

• Take once daily with food to ensure the medicine works.
• Separate indigestion remedies and mineral supplements from your dose as advised.
• Do not start other medicines or herbal products without checking for interactions.

Evidence & guidelines

Antiretroviral therapy selection and monitoring follow BHIVA and NICE guidance and are managed by specialist HIV services.