Risk-based early detection should be cost effective and widely accessible. EarlyCDT-Lung is a blood-based autoantibody biomarker which may improve accessibility to Low dose CT screening.  We randomized 12 208 individuals aged 50-75 at high risk of developing lung cancer to either the test or to standard clinical care. Outcomes were ascertained from Register of Deaths and Cancer Registry. Cox proportional hazards models were used to estimate the hazard ratio of the rate of deaths from all causes and lung cancer. Additional analyses were performed for cases of lung cancer diagnosed within two years of the initial test.    After 5 years 326 lung cancers were detected (2.7% of those enrolled). The total number of deaths reported from all causes in the intervention group was 344 compared to 388 in the control group.  There were 73 lung cancer deaths in the intervention arm and 90 in the controls (Adjusted HR 0.789 (0.636, 0.978). An analysis of cases of lung cancer detected within 2 years of randomization in the intervention group showed that there were 34 deaths from all causes and 29 from lung cancer.  In the control group there were 56 deaths with 49 from lung cancer. In those diagnosed with lung cancer within 2 years of randomization the hazard ratio for all cause mortality was 0.615 (0.401,0.942) and for lung cancer 0.598 (0.378, 0.946). Further large-scale studies of the role of biomarkers to target lung cancer screening, in addition to LDCT, should be undertaken.

F.M. Sullivan reports grants from Oncimmune and the Scottish Government Health and Social Care Directorate of the Chief Scientist Office, during the conduct of the study. F.S. Mair reports grants from Oncimmune and the Scottish Government Health and Social Care Directorate of the Chief Scientist Office, during the conduct of the study. W. Anderson has nothing to disclose. C. Chew has nothing to disclose. A. Dorward has nothing to disclose. J. Haughney has nothing to disclose. F. Hogarth reports grants from the Scottish Government Health and Social Care Directorate of the Chief Scientist Office and from Oncimmune, during the conduct of the study. D. Kendrick has nothing to disclose. R. Littleford reports grants from the Scottish Government Health and Social Care Directorate of the Chief Scientist Office and Oncimmune, during the conduct of the study. A. McConnachie reports grants from Oncimmune and the Scottish Government Health and Social Care Directorate of the Chief Scientist Office, during the conduct of the study. C. McCowan has nothing to disclose. N. McMeekin reports grants from Oncimmune and the Scottish Government Health and Social Care Directorate of the Chief Scientist Office, during the conduct of the study. M. Patel has nothing to disclose. P. Rauchhaus reports grants from Oncimmune and the Scottish Government Health and Social Care Directorate of the Chief Scientist Office, during the conduct of the study. L. Ritchie has nothing to disclose. J. Robertson reports other funding from Oncimmune, during the conduct of the study and other funding from Oncimmune, outside the study. J. Robertson was a founder of Oncimmune, a company spun out from the University of Nottingham based on his academic research. Between 2003 and 2013 he was Chief Scientific Officer of Oncimmune and a Director of the company. During this time, he was responsible for the original drafting of the ECLS protocol. Since 2013 he has had no involvement in the science or management of the company. He has been and remains a shareholder in the company. J. Sarvesvaran has nothing to disclose. H. Sewell reports other funding from Oncimmune, outside the submitted work and was an external member of the Oncimmune Scientific Advisory Board from 2006 to 2013. T. Taylor reports grants, nonfinancial support and other funding from Oncimmune, grants and personal fees from the Chief Scientist Office for Scotland, and grants and nonfinancial support from the Scottish Government, outside the submitted work. S. Treweek reports grants from Oncimmune and the Scottish Government Health and Social Care Directorate of the Chief Scientist Office, during the conduct of the study. K. Vedhara has nothing to disclose. S. Schembri reports grants from Oncimmune and the Scottish Government Health and Social Care Directorate of the Chief Scientist Office, during the conduct of the study.

the trial was registered at ClinicalTrials.gov with identifier NCT01925625

https://erj.ersjournals.com/content/57/1/2000670

Yes

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Institutional Review Board approval was provided by the East of Scotland Research Ethics Committee (REC 13/ES/0024).

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

Data can be accessed by applying to the ECLS data access committee on tehy template provided at https://eclsstudy.org/request-for-samples-and-data/