Comparative effectiveness of Paxlovid versus sotrovimab and molnupiravir for preventing severe COVID-19 outcomes in non-hospitalised patients: observational cohort study using the OpenSAFELY platform

Abstract ObjectiveTo compare the effectiveness of Paxlovid vs. sotrovimab and molnupiravir in preventing severe COVID-19 outcomes in non-hospitalised high-risk COVID-19 adult patients. DesignWith the approval of NHS England, we conducted a real-world cohort study using the OpenSAFELY-TPP platform. SettingPatient-level electronic health record data were obtained from 24 million people registered with a general practice in England that uses TPP software. The primary care data were securely linked with data on COVID-19 infection and therapeutics, hospital admission, and death within the OpenSAFELY-TPP platform, covering a period where both Paxlovid and sotrovimab were first-line treatment options in community settings. ParticipantsNon-hospitalised adult COVID-19 patients at high risk of severe outcomes treated with Paxlovid, sotrovimab or molnupiravir between February 11, 2022 and October 1, 2022. InterventionsPaxlovid, sotrovimab or molnupiravir administered in the community by COVID-19 Medicine Delivery Units. Main outcome measureCOVID-19 related hospitalisation or COVID-19 related death within 28 days after treatment initiation. ResultsA total of 7683 eligible patients treated with Paxlovid (n=4836) and sotrovimab (n=2847) were included in the main analysis. The mean age was 54.3 (SD=14.9) years; 64% were female, 93% White and 93% had three or more COVID-19 vaccinations. Within 28 days after treatment initiation, 52 (0.68%) COVID-19 related hospitalisations/deaths were observed (33 (0.68%) treated with Paxlovid and 19 (0.67%) with sotrovimab). Cox proportional hazards model stratified by region showed that after adjusting for demographics, high-risk cohort categories, vaccination status, calendar time, body mass index and other comorbidities, treatment with Paxlovid was associated with a similar risk of outcome event as treatment with sotrovimab (HR=1.14, 95% CI: 0.62 to 2.08; P=0.673). Results from propensity score weighted Cox model also showed comparable risks in these two treatment groups (HR=0.88, 95% CI: 0.45 to 1.71; P=0.700). An exploratory analysis comparing Paxlovid users with 802 molnupiravir users (11 (1.37%) COVID-19 related hospitalisations/deaths) showed some evidence in favour of Paxlovid but with variation in the effect estimates between models (HR ranging from 0.26 to 0.61). ConclusionIn routine care of non-hospitalised high-risk adult patients with COVID-19 in England, no substantial difference in the risk of severe COVID-19 outcomes was observed between those who received Paxlovid and sotrovimab between February and October 2022, when different subvariants of Omicron were dominant.