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. 2025 Jan;10(1):104086.
doi: 10.1016/j.esmoop.2024.104086. Epub 2024 Dec 18.

Globalization of clinical trials in oncology: a worldwide quantitative analysis

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Globalization of clinical trials in oncology: a worldwide quantitative analysis

F Izarn et al. ESMO Open. 2025 Jan.

Abstract

Background: Over the past two decades, the globalization of oncology clinical trials has expanded, yet significant disparities persist across countries. This study aimed to evaluate these geographical inequalities, the evolution of trial phases, and the adherence to ethical standards according to the World Bank's income group.

Materials and methods: The ClinicalTrials.gov database was searched and recorded in June 2024. We analyzed data from 87 748 oncology clinical trials conducted between 2000 and 2021, across high-income (HICs), upper-middle-income (UMICs), lower-middle-income (LMICs), and low-income countries. Key metrics included trial density, funding sources, registration timing, and trial phase distribution.

Results: The number of oncology trials increased significantly, with a mean absolute annual rise of 266.6 trials, with China currently being the leading site of early- and validation-phase trials. While HICs still present the highest trial densities, UMICs showed a notable increase in early-phase trials, reflecting a shift in research dynamics. However, despite these advances, 76.4% of countries still had no new trials initiated by 2024. Additionally, ethical practices saw improvement from 2005 to 2021 with an increase in pre-commencement registration (from 9.2% to 58%, P < 0.0001), and more validation-phase trials with a survival variable as the primary outcome (from 40% to 59.6%, P < 0.0001).

Conclusions: Despite the growth in oncology clinical trials, significant disparities in trial distribution and access remain, especially in LMICs. Continued investments in research infrastructure and adherence to ethical standards are crucial to ensure that clinical research benefits are equitably distributed, particularly in regions with the greatest need for advanced cancer therapies.

Keywords: clinical trials; ethical concerns; geography; inequality; oncology.

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Figures

Figure 1
Figure 1
Number of starting trials each year, according to their funding and purpose. ECT, educational/counseling/training; HSR, health services research; NA, not available.
Figure 2
Figure 2
Ongoing trials’ density map (per million of habitants).
Figure 3
Figure 3
Evolution of the weighted count of early- and validation-phase trials from 2005 to 2023. RoW, rest of the world (including all countries not specified under sites).

References

    1. Caston N.E., Williams C.P., Wan C., et al. Associations between geography, decision-making style, and interest in cancer clinical trial participation. Cancer. 2022;128:3977–3984. - PubMed
    1. Unger J.M., Hershman D.L., Till C., et al. “When offered to participate”: a systematic review and meta-analysis of patient agreement to participate in cancer clinical trials. J Natl Cancer Inst. 2021;113:244–257. - PMC - PubMed
    1. Epstein S. University of California Press; Berkeley: 1996. Impure Science: AIDS, Activism, and the Politics of Knowledge.http://ark.cdlib.org/ark:/13030/ft1s20045x/ Available at. - PubMed
    1. Thiers F.A., Sinskey A.J., Berndt E.R. Trends in the globalization of clinical trials. Nat Rev Drug Discov. 2008;7:13–14.
    1. Williams R. Celebrating 20 Years of ClinicalTrials.gov and Looking to the Future. 2020. https://nexus.od.nih.gov/all/2020/01/07/celebrating-20-years-of-clinical... Available at.

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