Loading
Life sciences · Journal article
Vaccine · July 20, 2026
Reinforces what was already believed, rather than introducing something new.
This prospective follow-up of 4470 ChAdOx1 nCoV-19 vaccine trial participants over 11.77 months median follow-up detected no emergent safety signals, with 174 SAEs and 71 AESIs recorded in 195 participants including 5 deaths. The study confirms the vaccine's acceptable long-term safety profile as established in earlier trials, although the authors emphasise that post-marketing surveillance must continue, particularly for neurological outcomes.
Prospective cohort follow-up study. Participants from the first clinical trials of ChAdOx1 nCoV-19 vaccine, with median age 50 years and 58% female; many subsequently received additional COVID-19 vaccines in the UK vaccination programme.. Intervention: ChAdOx1 nCoV-19 vaccine (initial dose in first clinical trials; many participants subsequently received additional COVID-19 vaccines). n = 4,470. UK (implied by reference to UK vaccination programme).
4470 participants enrolled between September 2021 and April 2022; 3845/4470 (86.0%) completed the study Median follow-up was 11.77 months with total follow-up of 48,116 person-months 174 serious adverse events and 71 adverse events of special interest recorded in 195 participants, including 5 deaths
Only 5 deaths reported with no details on causality assessment or comparison to background mortality rates 174 serious adverse events and 71 adverse events of special interest recorded in 195 participants, including 5 deaths
Clinicians and public health professionals can use this study to reassure patients and communities about the long-term safety of ChAdOx1 nCoV-19 vaccine based on 11.77 months of prospective follow-up data. However, the authors emphasise that ongoing post-marketing surveillance remains essential, particularly to monitor for delayed neurological disorders.
Prospective follow-up of pre-licensure trial participants with 4470 enrollees and 86% completion rate found no emergent safety signals over 11.77 months median follow-up, supporting the established safety profile of ChAdOx1 nCoV-19 vaccine.
As stated by the source record.
Quoted from the source exactly as published.
Clinicians and public health professionals can use this study to reassure patients and communities about the long-term safety of ChAdOx1 nCoV-19 vaccine based on 11.77 months of prospective follow-up data. However, the authors emphasise that ongoing post-marketing surveillance remains essential, particularly to monitor for delayed neurological disorders.
Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.
RATIONALE: Follow-up of pre-licensure trial participants potentially informs a vaccine's long-term safety profile. DESIGN: This prospective study enrolled participants from the first clinical trials of ChAdOx1 nCoV-19 vaccine, many of whom subsequently received COVID-19 vaccines in the UK vaccination programme. Serious adverse events (SAEs) and adverse events of special interest (AESIs) were captured. AESI selection was based on Brighton Collaboration definitions. RESULTS: Between September 2021 and April 2022, 4470 participants enrolled (58% female, median age 50 years); 3845/4470 (86.0%) completed the study. Median follow-up was 11.77 months; total follow-up was 48,116 person-months. There were 174 SAEs and 71 AESIs (33 events recorded as both) in 195 participants, including 5 deaths. Immunology data were available for a small subset of participants; total IgG against trimeric SARS-CoV-2 spike protein tended to increase during the study. CONCLUSIONS: Although no emergent safety signals were detected, continued post-marketing surveillance remains imperative, particularly for neurological disorders. EUDRACT NUMBER: 2021-003382-36.
Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.