Review

The n-of-1 clinical trial: the ultimate strategy for individualizing medicine?

Elizabeth O Lillie

Scripps Health, La Jolla, CA 92037, USA

The Scripps Translational Science Institute, La Jolla, CA 92037, USA

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Bradley Patay

Scripps Health, La Jolla, CA 92037, USA

The Scripps Translational Science Institute, La Jolla, CA 92037, USA

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Joel Diamant

Scripps Health, La Jolla, CA 92037, USA

The Scripps Translational Science Institute, La Jolla, CA 92037, USA

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Brian Issell

Scripps Health, La Jolla, CA 92037, USA

The Scripps Translational Science Institute, La Jolla, CA 92037, USA

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Eric J Topol

Scripps Health, La Jolla, CA 92037, USA

The Scripps Translational Science Institute, La Jolla, CA 92037, USA

The Scripps Research Institute, La Jolla, CA 92047, USA

The West Wireless Health Institute, La Jolla, CA 92037, USA

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Nicholas J Schork

† Author for correspondence

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Email the corresponding author at nschork@scripps.edu

Published Online:10 Mar 2011https://doi.org/10.2217/pme.11.7

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Abstract

N-of-1 or single subject clinical trials consider an individual patient as the sole unit of observation in a study investigating the efficacy or side-effect profiles of different interventions. The ultimate goal of an n-of-1 trial is to determine the optimal or best intervention for an individual patient using objective data-driven criteria. Such trials can leverage study design and statistical techniques associated with standard population-based clinical trials, including randomization, washout and crossover periods, as well as placebo controls. Despite their obvious appeal and wide use in educational settings, n-of-1 trials have been used sparingly in medical and general clinical settings. We briefly review the history, motivation and design of n-of-1 trials and emphasize the great utility of modern wireless medical monitoring devices in their execution. We ultimately argue that n-of-1 trials demand serious attention among the health research and clinical care communities given the contemporary focus on individualized medicine.

Keywords:

Papers of special note have been highlighted as: ▪ of interest

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Financial & competing interests disclosure

This work was supported in part by the following research grants: U19 AG023122-05; R01 MH078151-03; N01 MH22005, U01 DA024417-01, P50 MH081755-01, R01 AG030474-02, N01 MH022005, R01 HL089655-02, R01 MH080134-03, U54 CA143906-01; UL1 RR025774-03, from the Price Foundation (Zurich, Switzerland) and Scripps Genomic Medicine (CA, USA). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

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