Preliminary meta-analyses suggested that fluvoxamine was effective in treating COVID-19 infection. However, the reliability of this evidence has not yet been examined. MEDLINE, CENTRAL, EMBASE, PsycINFO, and ClinicalTrials.gov were searched to identify any randomized controlled trials (RCTs) from the inception of the databases to 5 February 2023. We used trial sequential analysis (TSA) to examine the reliability of the current existing evidence on the benefits of fluvoxamine on COVID-19 infection. The primary outcome was clinical deterioration, as defined in the original study (reported as odds ratio (OR), with 95% confidence intervals), and the secondary outcome was hospitalization. In the TSA, we used the relative risk reduction thresholds of 10, 20, and 30%. The updated meta-analysis of the five RCTs showed that fluvoxamine was not associated with lower odds of clinical deterioration when compared with a placebo (OR: 0.81; 0.59-1.11). The effect of fluvoxamine lay within the futility boundary (i.e., lack of effect) when using a 30% relative risk reduction threshold. The effect estimates lay between the superiority and futility boundary using the 10% and 20% threshold, and the required size of information was not reached for these two thresholds. The effect of fluvoxamine on the odds of hospitalization was not statistically significant (0.76; 0.56-1.03). In conclusion, there is no reliable evidence that fluvoxamine, when compared to a placebo, reduces the relative risk of clinical deterioration among adult patients with COVID-19 infection by 30%, and a relative risk reduction of 20% or 10% is still uncertain. The role of fluvoxamine as a COVID-19 treatment cannot be justified.
Keywords: COVID-19; deterioration; fluvoxamine; meta-analysis; trial sequential analysis.