A systematic review of basket and umbrella trials in oncology: the importance of tissue of origin and molecular target

Introduction We sought to characterise oncology basket and umbrella trials that have been implemented, determine how many have been completed, and calculate the response rate, by tumour type and drug target. Methods We conducted a retrospective, cross-sectional review of PubMed, Embase, and clinicaltrials.gov for all oncology basket and umbrella trials. We included all trials and publications reporting on the results of these trials, and we calculated overall response rates, stratified by tumour type and drug target. Results Most basket and umbrella trials are phase II and non-randomised in design. Of the 180 basket trials, 99 (55.0%) had published results and 81 (45.0%) did not. Of the 73 umbrella trials, 28 (38.4%) had published results and 45 (61.6%) did not. The median response rate was 14.0 (IQR: 4.2, 31.2) for basket trials and 17.8 (IQR: 3.8, 40.4) for umbrella trials. These responses varied, depending on tumour type and drug target. Conclusions Understanding what is known about these trials, especially given the limited but heterogenous response reported in these trials, provides context about the strengths and limitations of drugs, especially since several drugs have been approved in recent years for tumour-agnostic indications, based on the results of these types of trials.