Model-Driven Optimization of Subcutaneous Polymer Prodrugs Achieves Cancer Remission in Mice

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Pharmacology

Background:

• Chemotherapy limitations include toxicity and limited efficacy, driving nanocarrier development for improved drug delivery.
• Optimizing nanocarrier dosing regimens and reducing patient discomfort from intravenous administration are key challenges.

Purpose of the Study:

• To develop and validate a pharmacokinetic/pharmacodynamic (PK/PD) model for a novel subcutaneous injectable polymer nanocarrier.
• To identify optimal dosing regimens for improved chemotherapy efficacy and reduced toxicity.

Main Methods:

• Synthesized a paclitaxel (Ptx)-polyacrylamide (PAAm) water-soluble polymer prodrug via "drug-initiated" controlled radical polymerization.
• Developed and validated PK/PD models using data from MCF-7 tumor-bearing mice treated with intravenous Ptx and subcutaneous Ptx-PAAm.
• Identified optimal dosing regimens in silico and validated them in vivo.

Main Results:

• A validated PK/PD model was established for the subcutaneous nanocarrier.
• An optimized dosing regimen combining a loading dose and daily injections achieved a 60% complete response rate.
• The optimized regimen demonstrated efficacy without increased toxicity compared to previous methods.

Conclusions:

• This work presents the first validated PK/PD model for nanocarriers, offering a framework for improved drug development.
• The developed nanocarrier and optimized dosing strategy enhance chemotherapy effectiveness, reduce costs, and minimize patient discomfort.
• This approach paves the way for more efficient, cost-effective, and ethically considerate cancer drug development.