# Non-proportional hazards in immuno-oncology: Is an old perspective needed?

@article{Magirr2020NonproportionalHI, title={Non-proportional hazards in immuno-oncology: Is an old perspective needed?}, author={Dominic Magirr}, journal={Pharmaceutical statistics}, year={2020} }

A fundamental concept in two-arm non-parametric survival analysis is the comparison of observed versus expected numbers of events on one of the treatment arms (the choice of which arm is arbitrary), where the expectation is taken assuming that the true survival curves in the two arms are identical. This concept is at the heart of the counting-process theory that provides a rigorous basis for methods such as the log-rank test. It is natural, therefore, to maintain this perspective when extending… Expand

#### 6 Citations

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A modified weighted log-rank test (mWLR) that aims at balancing these factors by down-weighting events occurring when many patients have switched treatment by predicting the hazard ratio function and using it to compute the weights of the mWLR. Expand

DESIGNING GROUP SEQUENTIAL CLINICAL TRIALS WHEN A DELAYED EFFECT IS ANTICIPATED: A PRACTICAL GUIDANCE

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A common feature of many recent trials evaluating the effects of immunotherapy on survival is that non-proportional hazards can be anticipated at the design stage. This raises the possibility to use… Expand

Window mean survival time.

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The Strong Null Hypothesis and the MaxCombo Test: Comment on “Robust Design and Analysis of Clinical Trials with Nonproportional Hazards: A Straw Man Guidance form a Cross-Pharma Working Group.”

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A “straw-man guidance” on the design and analysis of clinical trials with non-proportional hazards and a proposal to replace the log-ra... Expand

Design and Analysis of group-sequential clinical trials based on a modestly-weighted log-rank test in anticipation of a delayed separation of survival curves: A practical guidance

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A common feature of many recent trials evaluating the effects of immunotherapy on survival is that non-proportional hazards can be anticipated at the design stage. This raises the possibility to use… Expand

Quantifying treatment differences in confirmatory trials under non-proportional hazards

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Results show that, under non-proportional hazards, the hazard ratio and weighted hazard ratio have no straightforward clinical interpretation whereas the RMST ratio can be interpreted regardless of the proportional hazards assumption. Expand

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