32% reduction in death from Covid from fluvoxamine (usually an antidepressant)
A 10-day course costs around $4. A well-known, essentially safe medication.
Study published in Lancet.
A proper trial, although there was earlier a test about this in France.
700 medicated and 700 placebo in Brazil (also of import, most Brazilians are not vaccinated). Treatment began 2-7 days after symptoms began.
It may have antiviral effect, but these aren't known. How does it work then? It's anti-inflammatory (it reduces inflammation inside the cells). Therefore it could prevent the cytokine storm (alveoli filling with fluid). Some antiplatelet activity also. Also increases plasma level of melatonin (improves sleep often).
Prozac (floxamine) is another SSRI (selective serotonin reuptake inhibitor), and though not currently known, may do the same thing.