Unveiling therapeutic dynamics: An in-depth comparative analysis of neutralizing monoclonal antibodies and favipiravir in alleviating COVID-19 outpatients impacts among middle-aged and special populations (MA-FAST).

Background: Neutralizing monoclonal antibodies (NMabs) are recognized for their efficacy against non-severe COVID-19. However, spike protein mutations may confer resistance. This study evaluates the effectiveness of favipiravir (FPV) versus NMabs in preventing severe COVID-19 in special populations.

Methods: A retrospective cohort was conducted on middle-aged, elderly, diabetic, or obese patients with COVID-19 treated with either FPV or NMabs. Propensity score matching (PSM) was used for analysis.

Results: The study included 1410 patients, resulting in four cohorts: middle-aged (36), elderly (48), diabetic (46), and obese (28) post-PSM. No significant differences were noted in 28-day emergency department (ED) visits across all groups between NMabs and FPV treatments, despite lower immunity in the FPV group. However, the diabetic group treated with FPV had higher 28-day hospitalization and oxygen supplemental, with no differences in the other groups. Intensive care unit (ICU) admissions, invasive mechanical ventilation, and mortality rates were similar between the two treatments.

Conclusions: Early dose-adjusted FPV showed no difference from NMabs in preventing ED visits, ICU admissions, ventilator needs, or mortality among patients with major comorbidities. Diabetic patients on FPV experienced higher hospitalizations and oxygen needs, with no observed differences in other groups. FPV may be a viable alternative, especially in settings with limited resources.