The pharmacokinetics of PEGylated liposomal doxorubicin are not significantly affected by sex in rats or humans, but may be affected by immune dysfunction

• Published in: Journal of controlled release Vol. 337; pp. 71 - 80
• Main Authors: Subasic, Christopher N., Kuilamu, Esther, Cowin, Gary, Minchin, Rodney F., Kaminskas, Lisa M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 10.09.2021
• Subjects: Cancer; Lymph; Nanomedicine; PEGylated liposomal doxorubicin; Personalised medicine; Pharmacokinetics; Sex effect; Sex effect; PEGylated liposomal doxorubicin; Personalised medicine; Pharmacokinetics; Nanomedicine; Cancer; Lymph
• ISSN: 0168-3659; 1873-4995
• DOI: 10.1016/j.jconrel.2021.07.006

PEGylated liposomal doxorubicin (PLD, Caelyx®, Doxil®) has been suggested to show significant sex-based differences in plasma clearance, as well as high inter-individual variability that may be driven by monocyte counts in cancer patients. This study aimed to establish if these differences are similarly observed in rats, which exhibit similar liposome clearance mechanisms to humans, and to use this model to identify sources of inter-individual and sex-based pharmacokinetic variability. The plasma and lymphatic pharmacokinetics of PLD were evaluated in male and female rats by quantifying doxorubicin as well as the 3H-labelled liposome. In general, the pharmacokinetics of doxorubicin and the 3H-liposome did not differ significantly between male and female rats when corrected for body surface area. Female rats did, however, show significantly higher doxorubicin concentrations in lymph compared to male rats. With the exception of serum testosterone concentrations in males, none of the physiological parameters evaluated correlated with plasma clearance. Further, reanalysis of published human data that formerly reported sex-differences in PLD plasma clearance similarly revealed no significant differences in PLD plasma clearance between males and females with solid tumours, but increased plasma clearance in patients with Kaposi's sarcoma (generally HIV+/immunocompromised). These data suggest that with the exception of lymphatic exposure, there are unlikely to be significant sex effects in the pharmacokinetics of liposomes, but immune function may contribute to inter individual variability. [Display omitted] •Absence of sex differences in PLD plasma clearance in healthy animals.•No sex differences in human PLD plasma clearance when HIV+ subjects are removed.•Higher lymphatic concentrations of PLD in females compared to males.•Liposome and total doxorubicin pharmacokinetics are similar after intravenous PLD.•Immune function in humans may predict PLD plasma clearanceβ.