Speaker
Description
Traditional drug efficacy assessment relies on cell viability and the IC$_{50}$ index. This index represents the concentration of drug required for cell viability to be 50%, i.e. the population of treated cells is half that of the control population. However, since early-stage cell populations follow Malthusian growth, viability is inherently time-dependent. This makes IC$_{50}$ a transient metric that fails to distinguish between different proliferation dynamics.
In this work, we propose a robust mathematical framework to analyze cell viability assays by focusing on effective growth rates rather than endpoint populations. Assuming exponential proliferation, we employ bootstrap resampling method to achieve precise exponential fits. This approach allows for the discovery of two new time-independent parameters: IC$_{\text{r}0}$, corresponding to a zero-growth rate, and IC$_{\text{rmed}}$,corresponding to a growth rate half that of the control \cite{sanchez2025assessment}.
Both indices provide a more biologically meaningful evaluation of drug efficacy. This methodology offers a standardized, mathematically based alternative to classical pharmacodynamics, ensuring that efficacy measurements reflect the real impact of a drug on cell proliferation regardless of the experimental timeframe.
Bibliography
@article{sanchez2025assessment,
title={Assessment of cell viability in drug therapy: IC50 and other new time-independent indices for evaluating chemotherapy efficacy},
author={S{\'a}nchez-D{\'\i}ez, Marta and Romero-Jim{\'e}nez, Paula and Alegr{\'\i}a-Aravena, Nicol{\'a}s and Gavira-O’Neill, Clara E and Vicente-Garc{\'\i}a, Elena and Quiroz-Troncoso, Josefa and Gonz{\'a}lez-Martos, Raquel and Ram{\'\i}rez-Castillejo, Carmen and Pastor, Juan Manuel},
journal={Pharmaceutics},
volume={17},
number={2},
pages={247},
year={2025},
publisher={MDPI}
}
