Finally, assuming that women resistant to HIV infection show a low activation of the immune system at the level of the female genital tract (FGT), HCQ has been investigated as a drug able to prevent HIV infection. It has been shown that the “immune quiescent” state of HIV-resistant women keeps the immune response against pathogens intact. For this reason, it was thought to induce pharmacologically, in a rabbit model, this immunological quiescence state through an intravaginal implant capable of providing a controlled release of HCQ. Considering that a concentration above 6.48 μg/mL of HCQ was able to interfere with the gp120 glycosylation process, the vaginal implant was projected to release HCQ with the longest possible duration at a concentration greater than 4.34 μg/mL but lower than 21.7 μg/mL. After six days, this implant improved mucosal epithelial integrity, reduced submucosal immune cell recruitment, decreased gene expression and protein of T cell activation markers, and minimized the activation of key pro-inflammatory mediators [25]. Hence, HCQ can be considered a promising drug able to maintain a low baseline level of immune activation and may also play a role in preventing HIV infection.