High-profile studies frequently and repetitively present data on the same patients, particularly in immunotherapy studies.

backgroundTraditionally, study results have been presented as abstracts at major scientific meetings at the conclusion of the analysis. Recently, presentations of studies in progress and updates to previously presented data have been allowed at major meetings. The frequency and implications of a single study being presented multiple times, particularly in high profile oral presentations, have not been fully evaluated.

methodsTo identify studies presented multiple times, abstracts from an approximately 1-year period from international conferences for three major societies devoted largely or in part to lung cancer research were assessed (ASCO 2015, World Lung 2015, ESMO 2015 and ASCO 2016). Abstracts were selected in a two-step process. The first step was for subject matter based on keywords: non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC) or immunotherapy. Searches differed slightly based on individual website functionality, with ASCO searched by track, World Lung by session and ESMO by individual abstract. In a second step, abstracts for which clinical outcome data was presented from a trial with an identifiable National Clinical Trial (NCT) number were selected. Immunotherapy abstracts that did not include the treatment of NSCLC or SCLC were excluded in the second step.

resultsA total of 851 abstracts were identified that were related to NSCLC, SCLC or immunotherapy. Of these, 357 referred to a clinical trial. In total, 110 of 357 (31%) described clinical trials that were presented multiple times (mean 2.75, range 2-7), and in 44 (12%), this occurred at the same conference. Of the 113 oral presentations, 75 (66%) presented data from clinical trials, either as posters or oral presentations. Further, 35 of the 113 (31%) oral presentations presented data from clinical trials that had generated other oral presentations. Of the 16 unique clinical trials leading to multiple oral presentations, a variety of issues led to the duplicate presentations, including different cohorts of the same trial, biomarker analysis, analysis by one study variable, or simply updated data. Moreover, 107 of the 357 (30%) clinical trial abstracts pertained to immunotherapy, including 4 of the 16 clinical trials generating multiple oral presentations. Of the 16 trials generating multiple oral presentations, 11 (69%) lead to a full-length publication by July 2017, including all of those pertaining to immunotherapy.

conclusionsThere is a pattern of multiple presentations of clinical trials, particularly in oral presentations, at major meetings. In most cases, data presented in subsequent oral presentations related entirely to patients whose data was presented in the previous oral presentation.