Changes in the use of end points in clinical trials for elderly cancer patients over time

Physicians need well-addressed clinical trials assessing benefits and harm of treatments to avoid under-treatment or over-treatment of elderly patients. The main objectives of this report were to present an overview of end points used in clinical trials dedicated to elderly patients; and to assess the evolution in chosen end points before and after the creation of the International Society of Geriatric Oncology in the early 2000s.

All phases I, II and III trials dedicated to the treatment of cancer among elderly patients published between 2001 and 2004 and between 2011 and 2014 were reviewed. All phase III clinical trials assessing cancer treatments among adults in the same periods were also reviewed to identify subgroup analyses of elderly patients among these trials.

Among phase III trials dedicated to elderly patients, overall survival was a common primary end point. Interestingly, tumor centered end points were very common in the first time period and very uncommon in the second time period, whereas composite end points were very uncommon in the first time period but very common in the second time period. Concerningly, disease-specific survival was very infrequently reported in dedicated clinical trials of elderly patients despite their importance in evaluating competing risk of death from non-oncology causes. The use of patient-reported outcomes (PROs) as a primary end point remained very uncommon but the reporting of PROs as a secondary end point tended to increase in the second time period, from 19% to 33% (P = 0.10). Functional status was infrequently reported.

During the past decade, the use of clinically meaningful end points such as PROs and functional status in elderly patients remained moderate. Yet, the use of PROs as a secondary end point tended to increase between the two time periods.