Introduction/Background Window-of-opportunity (window) trials are a useful trial design for investigating the biological effect of agents on endometrial cancer (EC). Women from ethnic minority backgrounds are typically underrepresented in clinical trials. However, in light of the differences in EC between different racial groups it is important that these women are recruited to window trials to ensure the results are truly representative.

Methodology A mixed methods study, comprising of a one-to-one verbal questionnaire and semi-structured interview, was conducted with women who had undergone treatment for EC within the past year. A strategic purposeful sampling was used to obtain opinions of women from diverse/social/ethnic/educational backgrounds. Questions explored the women’s background knowledge of clinical research, views of the type of medication they would consider taking as part of a window trial and their perceived barriers to participation.

Results Over half of women would consider participation although views on optimum time to receive trial information differed; at the time of diagnosis (62.5%), few days after diagnosis (25%). There was greater interest in agents derived from vitamins or food supplements rather than hormone-based drugs (75% compared 0% for ‘very likely’ to participate, respectively). Potential barriers to participation included the type of substances used and their perceived safety; concerns over potential side-effects; lack of knowledge/information about the trial; emotional/physical burden of the diagnosis whilst preparing for major surgery; perceived waiting time from the patients‘ perspective from diagnosis to curative surgery on outcome. Positive motivating factors included personal benefit, advancing scientific knowledge within the field, and helping to prevent women developing EC in the future.

Conclusion This study provides useful insight into women’s views on window trials in EC and identifies potential barriers for participation. The results will be used to develop patient information materials addressing women’s concerns in order to increase trial participation in the future.

Disclosure Nothing to disclose.