This is one of very many "possible" anti-COVID therapies where reading the reports you get completely unrealistic ideas of what is likely.
The could be here is one of maybe 20 or more could bes, and very few of them are likely to turn into real working treatments or prophylaxis. I have no idea whether this possibility is better or worse than the others.
Yes and just one of the of the studies I've posted could very well have ended this pandemic but there is no rush to trial these drugs. Vaccine vaccine vaccine. An approach that is failing worldwide to contain the virus.