Fig. 1

Identification of COVID-19 interventional clinical studies. Flow diagram of identification of COVID-19 interventional clinical studies on drugs or convalescent plasma planned to be carried out in Italy (update: 6 April 2021). Data source: AIFA website [15]; ClinicalTrials.gov [17]. *Assumption on experimental interventions: Escin (study identification number: NCT04475120) and lactoferrin (study identification number: NCT04322344) were included under the category dietary supplements; Nitric oxide (study identification numbers: NCT04290871 and NCT04290858) was included under the category “other”; Vitamin C (study identification number: NCT04323514) was included under the category drug taking into account dosage and route of administration. ^§Clinical studies identified from ClinicalTrials.gov registry already identified from the AIFA website were considered duplicates and information reported on the AIFA website was considered for analyses