Practice points for initial antiretroviral therapy

Practice points for initial antiretroviral therapy are described in Practice points for initial antiretroviral therapy. Monitor all patients taking antiretroviral drugs – see Monitoring antiretroviral therapy for HIV infection.

Table 1. Practice points for initial antiretroviral therapy
abacavir bictegravir cobicistat darunavir dolutegravir elvitegravir emtricitabine lamivudine raltegravir rilpivirine ritonavir tenofovir alafenamide tenofovir disoproxil fumarate, tenofovir disoproxil maleate, tenofovir disoproxil phosphate, tenofovir disoproxil succinate
Antiretroviral drug	Practice points
abacavir	Test for HLA-B5701 allele before prescribing. Presence of HLA-B5701 is highly predictive of hypersensitivity, which can be potentially fatal. Do not prescribe unless HLA-B5701 allele test is negative. Hypersensitivity reactions can occur in the absence of HLA-B5701, but this is rare. If hypersensitivity occurs, use of abacavir is contraindicated. Avoid in people with, or at high risk of, ischaemic heart disease. Suitable for initial therapy in combination with dolutegravir in patients with any HIV viral load. For patients with HIV viral load more than 100 000 copies/mL, seek expert advice before prescribing abacavir with antiretroviral drugs other than dolutegravir.
bictegravir	Can affect creatinine secretion, which is associated with elevated serum creatinine concentration; however, kidney function is not affected.
cobicistat [NB1]	Significant drug interactions can occur. Can affect creatinine secretion, which is associated with elevated serum creatinine concentration; however, kidney function is not affected.
darunavir	Always prescribed with boosting drugs (ie cobicistat or ritonavir). Significant drug interactions can occur. An increased dosage is required for patients previously treated with a protease inhibitor who have possible or proven darunavir resistance mutations (‘treatment experienced’ patients). Darunavir plus cobicistat is not recommended in pregnant people because this regimen is less effective; seek expert advice.
dolutegravir	Can affect creatinine secretion, which is associated with elevated serum creatinine concentration; however, kidney function is not affected.
elvitegravir	Always coformulated with the boosting drug cobicistat.
emtricitabine	Also treats hepatitis B virus. For patients with HIV and hepatitis B co-infection, combine with tenofovir alafenamide or a tenofovir disoproxil salt. If therapy is stopped, an acute exacerbation of hepatitis B can occur.
lamivudine	Also treats hepatitis B virus, but is not routinely recommended for HIV and hepatitis B co-infection. If therapy is stopped, an acute exacerbation of hepatitis B can occur.
raltegravir	Can increase serum creatine kinase concentration. Monitor the patient for symptoms of myopathy or rhabdomyolysis.
rilpivirine	Can affect creatinine secretion, which is associated with elevated serum creatinine concentration; however, kidney function is not affected. Significant drug interactions can occur. Should be taken with a main meal for optimal absorption. Only use rilpivirine for initial therapy in combination with NRTIs if the HIV viral load is less than 100 000 copies/mL and CD4 count is more than 200 cells/microlitre. In people with suppressed viral replication, rilpivirine may be used as long-acting injectable therapy in conjunction with injectable cabotegravir. Oral therapy may be used initially to assess tolerability before switching to injectable therapy.
ritonavir	Can be used as an alternative to cobicistat to increase the plasma concentration of some antiretroviral drugs. Significant drug interactions can occur.
tenofovir alafenamide	Tenofovir alafenamide is not interchangeable with tenofovir disoproxil formulations – check the intended formulation carefully before prescribing. Check kidney function before prescribing. Monitor kidney function for patients taking a tenofovir-based regimen. Significant drug interactions can occur. Dosing depends on the antiretroviral regimen used – check carefully before prescribing. Also treats hepatitis B virus. For patients with HIV and hepatitis B co-infection, combine with emtricitabine. If therapy is stopped, an acute exacerbation of hepatitis B can occur. If tenofovir alafenamide is not suitable (eg because of drug interactions), tenofovir disoproxil fumarate, tenofovir disoproxil maleate, tenofovir disoproxil phosphate or tenofovir disoproxil succinate can be used.
tenofovir disoproxil fumarate tenofovir disoproxil maleate tenofovir disoproxil phosphate tenofovir disoproxil succinate	Tenofovir disoproxil fumarate, tenofovir disoproxil maleate, tenofovir disoproxil phosphate and tenofovir disoproxil succinate are bioequivalent. However, they are not interchangeable with tenofovir alafenamide – check the intended formulation carefully before prescribing. Check kidney function before prescribing tenofovir disoproxil salts. Monitor kidney function for patients taking a tenofovir-based regimen. Tenofovir disoproxil salts have a higher risk of kidney and bone toxicity than tenofovir alafenamideWang 2016. Tenofovir disoproxil salts also treat hepatitis B virus. For patients with HIV and hepatitis B co-infection, combine with emtricitabine. If therapy is stopped, an acute exacerbation of hepatitis B can occur.
Note: NRTI = nucleoside/nucleotide reverse transcriptase inhibitor NB1: Cobicistat is not an antiretroviral drug; it is a cytochrome P450 3A4 inhibitor used to increase the plasma concentration of atazanavir, darunavir or elvitegravir.