The solubility of drugs, such as Remdesivir (REM) and Posaconazole (PCZ), is crucial for their formulation strategies and bioavailability. Veklury®, the marketed formulation of REM that was identified early as a promising therapeutic candidate for Covid-19 because of its ability to inhibit SARS-CoV-2 in vitro, contains ß-cyclodextrin in the form of betadex sulfobutyl ether sodium (SBECD) as a solubilizer. Each 100 mg dose of REM comprises 3 g of SBECD, i.e. REM:SBECD ratio 1:30, which cause many side effects including elevated levels of liver enzymes, which indicate inflammation or damage to liver cells. Thus, the present research work has been designed to replace the ß-cyclodextrin by utilizing the novel mPEG-b-PJL-COOH polymeric micelles that can improve the solubility of poorly soluble drugs at low polymer concentrations. Therefore, the micelles of mPEG-b-PJL-COOH were prepared by nanoprecipitation method to encapsulate REM. Till date, REM (3 mg) was successfully solubilized by 25 mg of the polymeric micelles. This result suggested that compared to the REM:SBECD ratio 1:30, the mPEG-b-PJL-COOH was able to solubilize REM with a much lower ratio i.e. 1:8. The electrostatic interaction between the basic REM andmPEG-b-PJL-COOH was the probable reason for increased entrapment efficiency, which suggest itspotential as a better alternative to the SBECD for the formulation of REM injection. The studies using PCZ are planned to prove the wider applicability of PJL polymers.

2024