The studies your referring to weren't given the drug till they were on ventilators and on their last legs,the drugs successes have been administered in the earlier stages not waiting till the last minute when the patients are on their deathbed after everything else failed.
I'm sure you aren't aware that that drug has been safely prescribed for decades as home(meaning no hospital supervision needed)use to treat arthritis,lupus as well several others not just malaria,that was only the first thing they found it useful on.
The heart problems/side effects are actually very rare only occuring in old people when takin in conjunction with other drugs...hell my ant has been taking it for the last decade.
As for the FDA warning on it look into their bogus reasoning behind declaring a drug to not be used outside of a hospital when it's been regularly/safely prescribed for decades as a daily medication.
Fact is the drug been negatively politicized and arguably less dangerous than others like Zoloft,paxel and others that have the same heart risks...had Trump said lunesta you CNN/MSNPC and every liberal working in the government sector with a say would be trash talking that too.
Look into other countries success with hydroxy chloroquine...even China is now using it.