Using maximum plasma concentration (C_max) to personalize taxane treatment and reduce toxicity

Taxanes are a widely used class of anticancer agents that play a vital role in the treatment of a variety of cancers. However, toxicity remains a major concern of using taxane drugs as some toxicities are highly prevalent, they can not only adversely affect patient prognosis but also compromise the overall treatment plan. Among all kinds of factors that associated with taxane toxicity, taxane exposure has been extensively studied, with different pharmacokinetic (PK) parameters being used as toxicity predictors. Compared to other widely used predictors such as the area under the drug plasma concentration curve versus time (AUC) and time above threshold plasma drug concentration, maximum plasma concentration (C_max) is easier to collect and shows promise for use in clinical practice. In this article, we review the previous research on using C_max to predict taxane treatment outcomes. While C_max and toxicity have been extensively studied, research on the relationship between C_max and efficacy is lacking. Most of the articles find a positive relationship between C_max and toxicity but several articles have contradictory findings. Future clinical trials are needed to validate the relationship between C_max and treatment outcome and determine whether C_max can serve as a useful surrogate endpoint of taxane treatment efficacy.