[jamesblonde]

Yes, that was my immediate take on the paper. However, the jury is still out if you take HCQ after the onset of sympthoms if that is also too late.

Based on this in-vitro study - https://www.nature.com/articles/s41421-020-0156-0 - if I hypothetically had both Chloroquine (CQ) and Hydroxychloroquine (HCQ), I would prefer HCQ for prophylaxis, but if I was exposed and likely infected or developed sympthoms, I would choose CQ. The loading time or HCQ is longer and it appears less effective at higher MOIs "the data suggest that the anti-SARS-CoV-2 activity of HCQ seems to be less potent compared to CQ, at least at certain MOIs."