https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7332204/

Nitazoxanidedemonstrates a good safety profile at approved doses. However, further evidence is required regarding hepatorenal and cardiovascular effects, as well as teratogenicity. We estimate that it would be possible to manufacture nitazoxanide as generic for $1.41 for a 14-day treatment course at 500 mg BD, up to $4.08 at 1100 mg TDS. Further trials in COVID-19 patients should be initiated. If efficacy against SARS-CoV-2 is demonstrated in clinical studies, nitazoxanide may represent a safe and affordable treatment in the ongoing pandemic.

"President Jair Bolsonaro said during a live broadcast from Facebook that he started taking another drug, in addition to hydroxychloroquine, for covid-19. The vermifuge cited by Bolsonaro is nitazoxanide"