465P - Reporting of older subgroups enrolled to registration breast cancer trials, 2012-2021

Background

Although older women comprise a large and rapidly growing proportion of patients diagnosed with breast cancer, the trial-level evidence base for treating this population is limited. This study assessed the completeness of reporting of older subgroups enrolled to registration trials in breast cancer between 2012-2021.

Methods

Trials which supported novel FDA approvals of systemic therapies in breast cancer between 01/2012 and 12/2021 were included. Individual trial-level PUBMED searches according trial/drug name, and trial registration number, were conducted on 31/08/22. Following title/abstract review, relevant publications and supplementary material were retrieved. Clinicaltrials.gov registry data was also retrieved. Non-efficacy (n = 1), site-agnostic (n = 1) biosimilar (n = 4), and trials conducted exclusively among premenopausal women (n = 1), were excluded. Immature endpoints (n = 5), for which no interim data were available in the full cohort, and studies which did not collect HRQOL data (n = 3), were excluded from relevant analyses. The availability and completeness of data for baseline characteristics, protocol-defined (co-)primary and secondary efficacy endpoints, toxicity, and HRQOL among older subgroups, was assessed systematically by two reviewers according to methods adapted from Chan & Altman (JAMA, 2004).

Results

27 trials were included. 785 unique publications were identified, of which 569 were excluded. 216 publications (median: 6 per trial, IQR: 4), and registry data, were assessed in full. 20.3% of enrolled patients were aged ≥65. 70.0% of patients were ECOG 0; 29.8% ECOG 1, and 0.2% ECOG 2. The completeness of data across efficacy endpoints, baseline characteristics, toxicity and HRQOL domains are reported in the table. Table: 465P

Completeness of reporting of geriatric subgroups enrolled to registration trials in breast cancer 2012-2022

Rows 1-4: n Endpoints (%) Rows 5-7: n Trials (%).

Conclusions

This study identified significant gaps in the reporting of older subgroups enrolled to registration breast cancer trials. Improved reporting practices are required to support evidence-based decision making in this population.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.