The DAWN antivirals trial: process evaluation of a COVID-19 trial in general practice

Background: The DAWN antivirals trial was a multicentric, randomised placebo-controlled trial evaluating antiviral medication for COVID-19 in general practice. The trial was prematurely terminated because of insufficient recruitment. Aim: To explore which factors contributed to the premature termination. Design & setting: General practice in Belgium. Method: Patients were randomised to camostat or placebo (patients and physicians blinded) between June 2021 and July 2022; a third arm evaluating molnupiravir (open label) was opened in March 2022. The outcome assessor was blinded for all comparisons except for the patient reported outcomes in case of molnupiravir. The authors analysed available trial data and evaluated trial context, implementation, and mechanisms of impact based on semi-structured interviews with trial stakeholders. Results: The trial recruited 44 participants; 19 were allocated to camostat (median age 55 years), 8 to molnupiravir (median age 60 years), and 17 to placebo (median age 56 years). There were no serious adverse events in either group. Most difficulties were related to the pandemic context: disruption to routine clinical services; multiple changes to the service model for COVID-19 patients; overwhelmed clinical staff; delays of trial medication; and staff shortages in the sponsor and clinical team. In addition, regulatory approval processes were lengthy and led to additional study procedures. It was felt that the trial started too late, when vaccinations had already begun. Conclusion: The DAWN antivirals trial was stopped prematurely. Although many barriers were related to the pandemic itself, hurdles such as a small and inexperienced sponsor and clinical teams, delays in regulatory processes, and research capacity in routine settings could be overcome by established research infrastructure and standardisation of processes.