Kaposi’s Sarcoma (KS) is one of the most common HIV-related malignancies. The incidence of KS has dramatically declined after the introduction of highly active anti-retroviral therapy (HAART). Some in vitro studies have reported direct antiangiogenic effects of protease inhibitors (PI). In some reports, tumour regression after starting a PI-based therapy has been described; however, non-randomized clinical trial have failed to confirm any significant difference between PI-based and non-nucleoside reverse transcriptase inhibitor-based regimens.

Here we describe the case of a patient who experienced a relapse of KS after switching from a PI-based to a PI-sparing regimen.