BackgroundCurrently, there are no specific effective treatments for SARS-CoV-2 infection; however, various COVID-19 treatment options are under investigation. It is vital to continue investigating the landscape of SARS-CoV-2–induced pneumonia and therapeutic interventions.ObjectiveThis paper presents the protocol for a randomized controlled trial that aims to compare the pneumonia exacerbation rate between ciclesonide (ALVESCO; Teijin Pharma Limited) administration and symptomatic treatment in patients with COVID-19 and to determine the efficacy of ciclesonide. The secondary objectives are to investigate the safety of ciclesonide administration, changes in clinical and laboratory findings, and the number of viral genome copies of SARS-CoV-2 over time between the 2 groups.MethodsIn this investigator-initiated, exploratory, prospective, multicenter, parallel-group, open-label, randomized controlled trial, a total of 90 patients diagnosed with COVID-19 will be recruited from 21 hospitals in Japan based on specific inclusion and exclusion criteria. Participants will be randomized either to the ciclesonide group, which will receive a 400-µg dose of ciclesonide 3 times per day over a 7-day period, or to the symptomatic treatment group. Both groups will receive antitussives and antipyretics as required. Data collection for various parameters will be conducted on days 1, 2, 4, 8, 22, and 29 to record baseline assessments and the findings over an extended period. Computed tomography images taken prior to drug administration and 1 week following treatment will be compared, and efficacy will be confirmed by checking for pneumonia exacerbation. Primary endpoint analysis will be performed using the Fisher exact test to determine statistically significant differences in the pneumonia exacerbation rate between the ciclesonide and symptomatic treatment groups.ResultsThe first trial participant was enrolled on April 3, 2020. Recruitment is expected to be completed on September 30, 2020, while follow-up assessments of all participants are expected to be completed by October 31, 2020. The study results will be published in a peer-reviewed scientific journal.ConclusionsThe RACCO (Randomized Ciclesonid COVID-19) study will provide definitive comparative effectiveness data and important clinical outcomes data between the ciclesonide and symptomatic treatment groups. If the hypotheses that pneumonia exacerbation rate reduction is more significant in the ciclesonide treatment group than in the symptomatic treatment group and that ciclesonide is safe for use are valid, ciclesonide will serve as an important therapeutic option for patients with COVID-19.Trial RegistrationJapan Registry of Clinical Trials jRCTs031190269; https://jrct.niph.go.jp/en-latest-detail/jRCTs031190269International Registered Report Identifier (IRRID)DERR1-10.2196/23830