The problem with this drug is that it inhibits one of the final stages in viral replication. This means that before it can work the virus has already infected the cell and added its RNA to the host cells DNA permanently.
So if a patient is exposed to HIV while on the drug, this will not prevent their cells from being infected with the virus. The infected cells will not subsequently create any virus, and therefore additional cells will not be infected, however nothing prevents actual exogenous HIV from infecting cells while on this drug.
That means that if someone discontinues the drug, cells that have been infected with HIV during the time they were on the drug can start producing it causing AIDS.
It’s great that there’s a drug that works as well as this for chronic use, but nobody should think that it’s actually preventing infection. It’s allowing infection but inhibiting viral replication post infection.
So if a patient is exposed to HIV while on the drug, this will not prevent their cells from being infected with the virus. The infected cells will not subsequently create any virus, and therefore additional cells will not be infected, however nothing prevents actual exogenous HIV from infecting cells while on this drug.
That means that if someone discontinues the drug, cells that have been infected with HIV during the time they were on the drug can start producing it causing AIDS.
It’s great that there’s a drug that works as well as this for chronic use, but nobody should think that it’s actually preventing infection. It’s allowing infection but inhibiting viral replication post infection.