BackgroundPatients infected with the novel coronavirus (SARS-CoV-2) are being treated empirically with oseltamivir, but there is little evidence from randomised controlled trials to support the treatment of coronavirus infections with oseltamivir.AimTo determine whether adding oseltamivir to usual care reduces time to recovery in symptomatic patients who have tested positive for coronavirus (not including SARS-CoV-2).Design and settingExploratory analysis of data from an open-label, pragmatic, randomised controlled trial during three influenza seasons, from 2016 to 2018, in primary care research networks, in 15 European countries.MethodPatients aged ≥1 year presenting to primary care with influenza-like illness (ILI), and who tested positive for coronavirus (not including SARS-CoV-2), were randomised to usual care or usual care plus oseltamivir. The primary outcome was time to recovery defined as a return to usual activities, with minor or absent fever, headache, and muscle ache.ResultsCoronaviruses (CoV-229E, CoV-OC43, CoV-KU1 and CoV-NL63) were identified in 308 (9%) out of 3266 randomised participants in the trial; 153 of these were allocated to usual care and 155 to usual care plus oseltamivir; the primary outcome was ascertained in 136 and 147 participants, respectively. The median time to recovery was shorter in patients randomised to oseltamivir: 4 days (interquartile range [IQR] 3–6) versus 5 days (IQR 3–8; hazard ratio 1.31; 95% confidence interval = 1.03 to 1.66; P = 0.026).ConclusionPrimary care patients with ILI testing positive for coronavirus (not including SARS-CoV-2) recovered sooner when oseltamivir was added to usual care compared with usual care alone. This may be of relevance to the primary care management of COVID-19.