This thesis aimed to investigate a new way of treating cancer and, in particular, renal cell carcinoma (RCC). Clear cell renal cell carcinoma (ccRCC), the most common subtype, is highly metastatic and resistant to conventional therapies. Current treatments, including tyrosine kinase inhibitors (TKIs) and histone deacetylase inhibitors (HDACIs), show limited efficacy due to drug resistance and toxicity. Combination therapy offers a promising solution by targeting multiple pathways simultaneously, reducing resistance risks. However, maintaining optimal drug ratios in vivo remains a challenge. Liposomes, as nanocarriers, enhance drug solubility, prolong circulation time, and minimize toxicity, thus enhancing patient compliance and treatment success. Co-encapsulation of drugs ensures synchronized delivery, preserving synergistic drug ratios.

This thesis explores liposomal formulations for co-delivering tubacin (HDACI) and erlotinib.HCl (TKI), previously identified as highly synergistic in ccRCC. Several methodological tools were used to accomplish this study. Concerning the formulation development, both passive loading via ethanol injection (tubacin) and active loading via ammonium sulfate gradient to form stable precipitates (erlotinib HCl). A Plackett-Burman design was used in the formulation optimization process. To address the co-encapsulation process, pH, lipid ratios, and loading methods were investigated to optimize stability. Lyophilisation protocols were prepared to improve the stability of the formulations, and trehalose vs. sucrose were evaluated as cryoprotectants to enhance their shelf-life. Finally, to assess the efficacy and safety of the encapsulated drugs, several in vitro models were used and a comparative analysis was performed between the multiple conditions.