While shenanigans like anon describes are definitely likely from big pharma, it is also true that there are numerous independent studies of HCQ in treating and preventing china virus infections. So it's going to be harder for pharma to hide the truth in this case.
In the niacin/statin trial, all it showed was that using the statin alone was fine, or that there could be a drug interaction with niacin or something. Niacin in other combinations or alone remains a viable part of cholesterol management.
Keeping in mind…
a) many of the independent entities are dependent on pharma for grants and such, but few are dependent on specific pharma companies nor are any wholly dependent on pharma alone
b) financial support must be disclosed, although funds are fungible, so it's possible a grant for a new building could enable an independent organization to do a clinical trial favor for a pharma company
c) That said, there are a ton of studies in this area with many having no direct involvement with pharma
d) Independent organizations doing spoopy studies for one sponsor don't get grants from other sourxces
(Pic related) Of the first 10 of 108 studies currently listed at ClinicalTrials.gov from a query for "hydroxychloroquine covid-19", NONE are sponsored (that is, organized and run by) a pharma company and only 1 has a pharma collaborator.
Just saying - there's a lot of good stuff going on and there is far more money to be made in other diseases than covid-19, so it's still a good chance that good and reliable data will be generated.
https://clinicaltrials.gov/ct2/results?cond=&term=hydroxychloroquine+covid-19