It is more accurate to say they are doing trials on the protease inhibitors lopinavir and ritonavir. These substances are potentiallythey are using HIV medicine to treat it so it makes me wonder just what the hell it really is
effective at preventing the reproduction of any virus that includes a protease chain. Their effectiveness in this case is not yet proven though.
Honestly, the list of anti-viral medications used in attempts to combat aids is so long that it would be surprising if a virus existed
that was wholly unaffected by that whole list. Just about every way we know of to stop a virus has been tried against HIV by now.
That said, there are other anti-virals that have been used against other coronaviruses, particularly
remdesivir, that I would hold out more hope for good trial results from, but we will have to wait and see.