Abstract
Cancer immunotherapy often reflects the improvement in both short-term risk reduction and long-term survival. In this scenario, a mixture cure model can be used for the trial design. However, the hazard functions based on the mixture cure model between two groups will ultimately crossover. Thus, the conventional assumption of proportional hazards may be violated and study design using standard log-rank test (LRT) could lose power if the main interest is to detect the improvement of long-term survival. In this paper, we propose a change sign weighted LRT for the trial design. We derived a sample size formula for the weighted LRT, which can be used for designing cancer immunotherapy trials to detect both short-term risk reduction and long-term survival. Simulation studies are conducted to compare the efficiency between the standard LRT and the change sign weighted LRT.
Original language | English |
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Pages (from-to) | 117-128 |
Number of pages | 12 |
Journal | Pharmaceutical Statistics |
Volume | 20 |
Issue number | 1 |
DOIs | |
State | Published - Jan 1 2021 |
Bibliographical note
Publisher Copyright:© 2020 John Wiley & Sons Ltd
Keywords
- clinical trial
- crossing hazards
- mixture cure model
- sample size calculation
- weighted log-rank test
ASJC Scopus subject areas
- Statistics and Probability
- Pharmacology
- Pharmacology (medical)