Atazanavir, Ritornavir (Interaction)

It is very frequent for HIV-infected patients to develop fungal infections. In this regard, it is quite common for patients with HIV to be co-prescribed atazanavir/ritonavir (ATZ/RIT) together with the antifungal voriconazole (it is a triazole antifungal agent) or other antifungals.

However, there may be interactions between the antiretroviral agent and the antifungals used that can lead to serious adverse reactions, such as liver damage.

For this reason, it is very important to monitor the adverse effects that occur when these two drugs are prescribed concomitantly and, if necessary, eliminate the antifungal agent, reduce the dose, or change it to another agent that does not cause these interactions with atazanavir.

The EMA (“European Medicines Agency”) states that the co-administration of atazanavir/ritonavir together with voriconazole is not recommended unless a benefit/risk study is established that justifies the use of both drugs combined. For this reason, it is highly important to be able to determine certain genetic variants that are involved in the metabolism of voriconazole and other triazole antifungal agents. If it is not possible to carry out a genetic study of these variants, strict monitoring of the safety and efficacy of this combined treatment must be carried out.

In this item we analyze the genetic variants that affect the interaction between atazanavir and voriconazole and their relationship with the development of severe side effects.