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Stopping clinical trials by design

Nature Reviews Drug Discovery volume 3, pages 973–977 (2004)Cite this article

Abstract

Before any clinical trial begins, a detailed trial protocol must be prepared. The authority of the trial results will depend on the quality of this document. In many protocols, a key component is a plan for a series of interim analyses of the accumulating trial data, and a 'stopping rule' based on them. Such a rule might be intended to prevent participants from continuing to receive a drug that already seems to be unsafe, or to allow a successful drug to become generally available as soon as sufficient evidence of its advantages has been collected. There has been considerable misunderstanding of these rules, and controversies associated with them. Here, I discuss why this might be, and what can be done to promote their successful and beneficial use in the future.

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Authors and Affiliations

  1. Medical and Pharmaceutical Statistics Research Unit, The University of Reading, PO Box 240, Earley Gate, Reading, RG6 6FN, UK

    John Whitehead

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Competing interests

J.W. is Director of the Medical and Pharmaceutical Statistics Research Unit, a self-financing, non-profit making part of the University of Reading. The unit receives sponsorship from and engages in consultancy for the pharmaceutical industry, particularly with respect to the conduct of sequential clinical trials. The Unit also markets the software package PEST for the implementation of such designs.

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Whitehead, J. Stopping clinical trials by design. Nat Rev Drug Discov 3, 973–977 (2004). https://doi.org/10.1038/nrd1553

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