I’ve heard that old malaria medications, like chloroquine or hydroxychloroquine, might now be useful, is this true?

Data published on May 22,2020 in a large multinational data analysis with over 90,00 patients has found no benefit of hydroxychloroquine. The findings show increased rates of cardiac toxicity in those patients who received hydroxychloroquine. To date this is the only published article that has studied this drug and it’s potential efficacy in COVID patients. The study can be found here. (May 22, 2020)

Further Sources:
https://www.nytimes.com/article/coronavirus-hydroxychloroquine-malaria.html
https://forbetterscience.com/2020/03/26/chloroquine-genius-didier-raoult-to-save-the-world-from-covid-19/
https://www.wired.com/story/an-old-malaria-drug-may-fight-covid-19-and-silicon-valleys-into-it/