Not as famous as ivermectin, hydroxychloroquine (aka "HCQ") was an "also ran" in the list of existing, well-known and reliable medications that could have been used during the COVID-19 pandemic. It reached this accolade due to US President Donald Trump's reference in one of his pandemic briefings, which meant that the entire world had to immediately ban it lest they be seen to agree with something The Orange One uttered.

Why do I say this?

There was a CDC-funded study in 2005 that showed hydroxychloroquine was highly effective against coronaviruses (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1232869/).

So you might say the CDC knew it could have worked to help cure people during the pandemic.

Reviews of 420 studies show HCQ had a 65% benefit again COVID-19 when the patient was treated early.

For further details, Dr Meryl Nass has written about this several times, the best one explaining the false narrative around hydroxychloroquine, which is very detailed and includes all references.

Update 2024-02-23: A new two hour documentary has just been released that details the corruption over hydroxychloroquine, it is worth watching: https://brokentruth.com/epidemic-of-fraud/