Clinical trials for older cancer patients: A systematic review

Abstract

Older adults are underrepresented in clinical trials, and studies specifically focused on older cancer patients are uncommon. By screening PubMed, EMBASE and proceedings from international meetings, we searched for trials testing systemic therapies in solid cancer patients aged ≥70 years. We identified age-unselected trials testing the same intervention in the same setting. The primary objective was to assess the proportion of older-age-selected trials meeting the target accrual. Secondary objectives included the analysis of the use of geriatric assessment (GA) tools and quality of life (QoL) questionnaires, and the comparison between older-age-selected and matching age-unselected trials. We included 313 trials (10.9 % phase I, 78.6 % phase I/II-II, and 10.5 % phase III). 7.7 % were published in 1990-2000, 40.3 % in 2001-2011, and 52.1 % in 2012-2023. Of 234 evaluable trials, 77.8 % enrolled ≥90 % of the required patients. Premature study discontinuation occurred in 50 cases (5.9 % phase I, 14.2 % phase II, 39.4 % phase III). Among 232 evaluable trials, 60.3 % met the primary endpoint (63.7 % phase I/II-II, 35.5 % phase III). GA and QoL analyses were carried out in 28.1 % and 23 % of trials, respectively. Corresponding age-unselected trials were identified for 154 older-age-selected trials. Compared with age-unselected trials, a lower proportion of older-age-selected trials met the target accrual (83.5 % vs 94.8 %, p = 0.035) or the primary endpoint (63.9 % vs 81.5 %, p = 0.022). In conclusion, older-age-selected trials are increasingly performed but rarely include GA and QoL analyses. Effective strategies to meet target accrual should be implemented especially for phase III trials, which suffer from high rates of premature discontinuation.

Keywords: Cancer; Clinical trials; Geriatric oncology; Older adults; Quality of life; Systematic review.