A rising emphasis of the early-stage clinical judgments

The proportion of early-stage drug trials tackling the biggest cancer killers has declined sharply since the early 1990s as less common tumour types receive increasing attention, according to new research to be presented during the International Congress on Targeted Anticancer Therapies (TAT) 2019, taking place from today to 27 February in Paris, France.

(1) The analysis highlights the changing treatment landscape, with doctors and pharmaceutical companies evaluating an expanding range of molecularly-targeted anticancer drugs and immunotherapy.

“Our study clearly shows the common cancer types are decreasing as a proportion of the patients in phase 1 studies and the uncommon types are increasing,” said Dr Jun Sato of the National Cancer Center Hospital, Japan, lead author of the latest research.

“The development of new treatment options means there are now multiple approaches to address an increasingly broad spectrum of different types of cancer.”

They found that the proportion of phase 1 trials in which patients with either colorectal or lung cancer accounted for at least half of the enrolled group declined markedly over time, from 46.3% in 1991-95 to just 16.7% in 2011-15. The trend was consistent across North America, Europe and Asia.

Importantly, the absolute number of trials involving a majority of colorectal or lung cancer patients still rose over the period, from 31 to 41, but this was far less than the increase in trials focused on rarer cancer types.

Lung and colorectal cancer are the most common causes of cancer death globally, accounting for 2.6 million of an estimated 9.6 million cancer deaths in 2018, according to the World Health Organization.

(2)The 1991-2015 timespan chosen for the analysis coincides with a revolution in cancer therapy, driven by the development of molecularly-targeted anticancer drugs and application of comprehensive molecular profiling techniques for patient selection in clinical trials. Initially, from 1990s to early 2000s, scientists used these advances to investigate large cancer populations with frequent genomic mutations, but over time, the focus of genomic-driven clinical trials has shifted to less common mutations and rarer tumour types.