A case report of a non virological response to a DTG-based regimen, in a patient infected with a E157Q-mutated virus, has been described despite adequate DTG plasma concentrations . In vitro characterization of the E157Q-mutated virus issued from this clinical sample has shown that integrase strand-transfer activity was 3-fold greater compared to wild-type virus and that IC50 value was increased, leading to a FC equal to 9 .