PDXpower: A Power Analysis Tool for Experimental Design in Pre-clinical Xenograft Studies for Uncensored and Censored Outcomes

Li, Shanpeng; Telesca, Donatello; Kornblum, Harley I.; Nathanson, David; Pajonk, Frank; Cui, Elvis Han; Palmer, Joycelynne; Li, Gang

doi:10.51387/25-NEJSDS76

The New England Journal of Statistics in Data Science

PDXpower: A Power Analysis Tool for Experimental Design in Pre-clinical Xenograft Studies for Uncensored and Censored Outcomes

Shanpeng Li Donatello Telesca Harley I. Kornblum All authors (8)

https://doi.org/10.51387/25-NEJSDS76

Pub. online: 5 February 2025 Type: Cancer Research

Open Access

Accepted
24 January 2025

Published
5 February 2025

Abstract

In cancer research, leveraging patient-derived xenografts (PDXs) in pre-clinical experiments is a crucial approach for assessing innovative therapeutic strategies. Addressing the inherent variability in treatment response among and within individual PDX lines is essential. However, the current literature lacks a user-friendly statistical power analysis tool capable of concurrently determining the required number of PDX lines and animals per line per treatment group in this context. In this paper, we present a simulation-based R package for sample size determination, named ‘PDXpower’, which is publicly available at The Comprehensive R Archive Network (https://CRAN.R-project.org/package=PDXpower). The package is designed to estimate the necessary number of both PDX lines and animals per line per treatment group for the design of a PDX experiment, whether for an uncensored outcome, or a censored time-to-event outcome. Our sample size considerations rely on two widely used analytical frameworks: the mixed effects ANOVA model for uncensored outcomes and Cox’s frailty model for censored data outcomes, which effectively account for both inter-PDX variability and intra-PDX correlation in treatment response. Step-by-step illustrations for utilizing the developed package are provided, catering to scenarios with or without preliminary data.

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Full article

Open access article under the CC BY license.

Keywords

Frailty model Mixed effects ANOVA model Power analysis Sample size determination Xenograft study

Funding

This research was partially supported by National Institutes of Health (P50CA211015, P30 CA-16042, R01NS121319, P50 CA092131, and P01CA236585, GL, P30 CA-033572, JP), and the National Center for Advancing Translational Sciences (UL1-TR-001420, GL).

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