FWIW we all might pause to look at the graph posted at
https://aapsonline.org/preliminary-injunction-sought-to-rele...
showing that countries using HCQ have much lower case fatality rates than countries such as the USA where use of HCQ is either banned or discouraged. [There's another graph similar but with many more countries. I can't find it at the moment. It is even more dramatic.]
Concerning your post:
HCQ+Zinc+Zithromax was initially proposed as an early treatment for Covid-19. The two studies you name test for something completely different: whether HCQ can prevent Covid-19 in someone who has been recently exposed to Covid-19.
But no one ever claimed that HCQ could prevent someone from getting Covid-19.
The claim was instead that, if given early in the course of the disease, HCQ+ZINC+ZITHROMAX would alleviate Covid-19. That is, HCQ+ZINC+ZITHROMAX, when given to people who have a recent diagnosis of Covid-19, usually proves beneficial. In particular it lowers the hospitalization rate and death rate significantly.
There are
- a. drugs that prevent illnesses(e.g., vaccines) from becoming established in the human body,
- b. drugs that alleviate illnesses(HCQ for Covid-19) once they are already established in the human body,
-c. drugs that do both (HCQ in the case of malaria, which HCQ can both prevent and treat (indeed, cure the disease)).
Testing protocols for these differ accordingly.