Although there is a very low quality of evidence on drug interaction between the two medicines, the current combination is not recommended. This is due to the fact that these drugs have the same active substance – emtricitabine. It’s very important to consult with a healthcare provider for safe prescription and alternative medication if needed.
Tenofovir DF and emtricitabine are the two active substances in HIV PrEP, an anti-HIV medicine. This drug belongs to the nucleoside reverse transcriptase inhibitor (or NRTIs) class of drugs.
Truvada in combination with other antiretroviral agents is used to prevent the virus from replicating and affecting the CD4+ cells. Together with other recommended safer sex practices, Truvada is used alone as a PrEP remedy to prevent or reduce the risk of HIV attraction in high-risk uninfected individuals. Also, this drug can be used as PEP (occupational and nonoccupational exposure) with other meds such as a protease inhibitor or integrase inhibitor [1].
Descovy is a two-in-one drug formulation of NRTIs. It contains emtricitabine and tenofovir alafenamide (also called TAF) as active ingredients. Descovy is indicated for the treatment of HIV infection in combination with other antiretroviral meds. It’s prescribed for patients who are 12+ years of age.
TAF is a prodrug of TFV and a potential successor of TDF. TAF has a better safety profile as it does not cause the same level of lower bone density or kidney problems that TDF does. Descovy is also approved as a PrEP medicine– the next-generation virus prevention drug alternative to Truvada [2]. Although these tabs are non-inferior to Truvada, its safety profile to BMD and kidneys makes Descovy the better choice in HIV treatment and PrEP, especially in individuals with severe bone and kidney problems.
Drug interaction between Descovy and Truvada is very low. The main concern is the active substances that both drugs have. They contain both emtricitabine and tenofovir with Descovy having a slightly improved version of TDF called TAF.
It is advisable not to coadminister drugs that have the same active substance, as the mixture of similar tabs can raise the levels of the main ingredient and are likely to cause health problems. Like TAF, TDF is hydrolyzed to tenofovir (TFV) in plasma before being diphosphorylated to its active form – TFV diphosphate (TFV-DP) [3].