Combining drugs and extending treatment — a PFS end point is not sufficient

In studies investigating the combination of two or more anticancer drugs that are already approved for independent use, or 'maintenance' regimens, the use of progression-free survival as the end point for approval is inadequate; sequential treatment with the same agents or existing salvage therapies, respectively, might provide an equivalent survival benefit, with lower toxicity, cost, and treatment burden, therefore, the use of an overall survival end point is essential to justify such interventions.

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Correspondence to Vinay Prasad.

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The authors declare no competing financial interests.

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Selected studies of combination and maintenance therapies in oncology (DOC 56 kb)

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Gyawali, B., Prasad, V. Combining drugs and extending treatment — a PFS end point is not sufficient. Nat Rev Clin Oncol 14, 521–522 (2017).

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