Hi Kdagi, thanks for your question. Because our test looks for antibodies to HIV rather than the virus, somebody who is on treatment and virally supressed (undetectable) should still show a true positive result. However due to lack of extensive clinical data it is not possible to claim that a person who is on anti-retroviral treatment will always get an accurate result. A person who is virally supressed and is taking their medicine correctly cannot pass the virus on though, even through unprotected sex. This is where the phrase Undetectable = Untransmittable (U=U) comes from. Thanks for choosing BioSURE - Team BioSure