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Individualized therapy trials: navigating patient care, research goals and ethics

Abstract

‘Individualized therapy’ trials (sometimes called n-of-1 trials) use patients as their own controls to evaluate treatments. Here we divide such trials into three categories: multi-crossover trials aimed at individual patient management, multi-crossover trial series and pre–post trials. These trials all customize interventions for patients; however, the latter two categories also aim to inform medical practice and thus embody tensions between the goals of care and research that are typical of other types of clinical trials. In this Perspective, we discuss four domains where such tensions play out—clinical equipoise, informed consent, reporting and funding, and we provide recommendations for addressing each.

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Fig. 1: Different designs and settings for individualized therapy trials.

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Acknowledgements

We thank H. Moyer for research assistance. Funding was provided by a large-scale applied research project grant from Genome Canada, and by CIHR.

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Peer review information Nature Medicine thanks Annemieke Aartsma-Rus, Richard L. Kravitz and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Karen O’Leary was the primary editor on this article and managed its editorial process and peer review in collaboration with the rest of the editorial team.

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Kane, P.B., Bittlinger, M. & Kimmelman, J. Individualized therapy trials: navigating patient care, research goals and ethics. Nat Med 27, 1679–1686 (2021). https://doi.org/10.1038/s41591-021-01519-y

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