tipranavir + ritonavir + saquinavir

This is a combination of three distinct HIV-1 protease inhibitors: **tipranavir**, **ritonavir**, and **saquinavir**, used together as part of a multi-drug antiretroviral regimen for the treatment of HIV infection, typically in patients with resistance to standard therapies. Tipranavir is unique as a non-peptidic protease inhibitor designed for efficacy against protease-inhibitor-resistant HIV strains. Ritonavir serves primarily as a pharmacokinetic enhancer by inhibiting cytochrome P450 3A4 (CYP3A4), thereby increasing the plasma concentrations and efficacy of co-administered protease inhibitors. Saquinavir is a peptidomimetic protease inhibitor that blocks HIV protease, preventing viral maturation. Clinical evidence suggests that while ritonavir boosting is a well-established strategy, the simultaneous triple combination of tipranavir, ritonavir, and saquinavir is generally not recommended due to significant pharmacokinetic interactions leading to decreased plasma concentrations of saquinavir and potentially reduced efficacy, with possible increased toxicity.