A very interesting study was published recently in medRxiv: Outpatient treatment of Covid-19 with metformin, ivermectin, and fluvoxamine and the development of Long Covid over 10-month follow-up.
Patients with Covid were treated with metformin (a common diabetes drug), ivermectin, or fluvoxamine (or a placebo). To quote the results:
There was a 42% relative decrease in the incidence of Long Covid in the metformin group compared to its blinded control in a secondary outcome of this randomized phase 3 trial.
Carolyn T. Bramante et al
There was no statistically signficiant improvement with the other two drugs.
Participants were given the drug within three days of testing positive. The metformin dose was titrated over 6 days: 500mg on day 1, 500mg twice daily for 4 days, then 500mg mornings and 1000mg evening through 14 days.