IBIS-II Observational (IBIS-II-O)
Research type
Research Study
Full title
IBIS-II-O: Long term observational follow up of previous participants of the IBIS-II studies: DCIS and Prevention
IRAS ID
258590
Contact name
Jack Cuzick
Contact email
Sponsor organisation
QMUL, Joint Research Management Office
Duration of Study in the UK
6 years, 11 months, 29 days
Research summary
IBIS-II-O is the long term observational study of the IBIS-II Prevention and DCIS clinical trial participants.
The IBIS studies have investigated preventive agents for breast cancer since 1992. IBIS-I compared tamoxifen to placebo for women with increased risk of breast cancer. IBIS-II Prevention (n=3864) compared anastrozole with placebo in women at increased risk and IBIS-II DCIS (n=2980) to compared anastrozole to tamoxifen in women with excised ductal Carcinoma in Situ (DCIS). The findings have contributed to national guidelines on the clinical management of women at increased risk of developing breast cancer (NICE recommendation CG164).
Active treatment for Prevention and DCIS trials stopped in 2017 but long-term follow up continues to determine the benefit and risk of preventive agents as divergence between treatment groups may not become clear until decades after the intervention has stopped(Cuzick, 2015). However, collecting follow-up data over extended periods of time is complex, expensive, and challenging to both trialists and participating sites (Kilburn, 2014).
Comparison of events in data from NHS Digital registry between 2000-2016 with existing IBIS-II data-sets (UK cohort) showed that the registry duplicated patient-reported breast cancer cases already reported but identified breast cancers and deaths in participants withdrawn or lost to follow up plus higher incidences of significant clinical events such as fractures, cardiovascular events and other cancers across the whole cohort reported in the IBIS-II database.
Given the reduced risk to the IBIS-II cohorts, reliability of digital registries and the value in extending the current follow-up period, IBIS-II-O provides the framework to continue to meet the scientific objectives set in the IBIS-II Prevention and DCIS protocols beyond the current end of study definition in 2022 using remote ‘flagging’ data from NHS Digital and Public Health England registries only.
REC name
London - Fulham Research Ethics Committee
REC reference
19/LO/0984
Date of REC Opinion
31 Jul 2019
REC opinion
Further Information Favourable Opinion