Figure 3. Assessment of heterogeneity of Metformin treatment effect for preventing the development of Long Covid compared to blinded control.

In this factorial design trial, each participant received two types of pills. Every participant received a pill that looked like metformin -- either metformin or an exact-matching metformin placebo. The second pill was active fluvoxamine or ivermectin, or exact matching placebo for fluvoxamine or ivermectin.

Fluvoxamine enrollment halted on January 7, 2022 by the independent data and safety monitoring board. Overall trial enrollment completed on January 28, 2022 when reaching the target sample size.