stockorus - I wondered the same thing with that FDA letter back in May.
It seems to be treatment specific. They only speak of it specific to the COVID treatment as it hasn't been 'proven' to be either safe and effective. Logic shows though that if the molecule is the same in the HIV therapy makeup and it is same for the Covid therapy, the one would easily put 1 and 1 together to make it 2.
Not sure why the FDA thought 1+1=0. A 3 year old can get the answer to that simple equation..