Mechanochemically induced solid state transformations: The case of raloxifene hydrochloride

Anti-EGFR immunoliposomes for cabazitaxel delivery: From formulation development to in vivo evaluation in prostate cancer xenograft model

Liposomes functionalized with monoclonal antibodies offer targeted therapy for cancer, boasting advantages like sustained drug release, enhanced stability, passive accumulation in tumors, and interaction with overexpressed receptors on cancer cells. This study aimed to develop and characterize anti-EGFR immunoliposomes loaded with cabazitaxel and assess their properties against prostate cancer in vitro and in vivo. Using a Box-Behnken design, a formulation with soy phosphatidylcholine, 10% cholesterol, and a 1:20 drug-lipid ratio yielded nanometric particle size, low polydispersity and high drug encapsulation. Immunoliposomes were conjugated with cetuximab through DSPE-PEG-Maleimide lipid anchor. Characterization confirmed intact antibody structure and interaction with EGFR receptor following conjugation. Cabazitaxel was dispersed within the liposomes in the amorphous state, confirmed by solid-state analyses. In vitro release studies showed slower cabazitaxel release from immunoliposomes. Immunoliposomes had enhanced cabazitaxel cytotoxicity in EGFR-overexpressing DU145 cells without affecting non-tumor L929 cells. Cetuximab played an important role to improve cellular uptake in a time-dependent fashion in EGFR-overexpressing prostate cancer cells. In vivo, immunoliposomes led to significant tumor regression, improved survival, and reduced weight loss in xenograft mice. While cabazitaxel induced leukopenia, consistent with clinical findings, histological analysis revealed no evident toxicity. In conclusion, the immunoliposomes displayed suitable physicochemical properties for cabazitaxel delivery, exhibited cytotoxicity against EGFR-expressing prostate cancer cells, with high cell uptake, and induced significant tumor regression in vivo, with manageable systemic toxicity.

Current Applications of Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) in Pharmaceutical Analysis: Review

The present review encompasses various applications of multivariate curve resolution- alternating least squares (MCR-ALS) as a promising data handling, which is issued by analytical techniques in pharmaceutics. It involves different sections starting from a concise theory of MCR-ALS and four detailed applications in drugs analysis. Dissolution, stability, polymorphism, and quantification are the main four detailed applications. The data generated by analytical techniques associated with MCR-ALS deals accurately with different challenges compared to other chemometric tools. For each reviewed purpose, it was explained how MCR-ALS was applied and detailed information was given. Different approaches were introduced to overcome challenges that limit the use of MCR-ALS efficiently in pharmaceutical mixture were also discussed.

DOPE/CHEMS-Based EGFR-Targeted Immunoliposomes for Docetaxel Delivery: Formulation Development, Physicochemical Characterization and Biological Evaluation on Prostate Cancer Cells

Docetaxel (DTX) is a non-selective antineoplastic agent with low solubility and a series of side effects. The technology of pH-sensitive and anti-epidermal growth factor receptor (anti-EGFR) immunoliposomes aims to increase the selective delivery of the drug in the acidic tumor environment to cells with EFGR overexpression. Thus, the study aimed to develop pH-sensitive liposomes based on DOPE (dioleoylphosphatidylethanolamine) and CHEMS (cholesteryl hemisuccinate), using a Box–Behnken factorial design. Furthermore, we aimed to conjugate the monoclonal antibody cetuximab onto liposomal surface, as well as to thoroughly characterize the nanosystems and evaluate them on prostate cancer cells. The liposomes prepared by hydration of the lipid film and optimized by the Box–Behnken factorial design showed a particle size of 107.2 ± 2.9 nm, a PDI of 0.213 ± 0.005, zeta potential of −21.9 ± 1.8 mV and an encapsulation efficiency of 88.65 ± 20.3%. Together, FTIR, DSC and DRX characterization demonstrated that the drug was properly encapsulated, with reduced drug crystallinity. Drug release was higher in acidic pH. The liposome conjugation with the anti-EGFR antibody cetuximab preserved the physicochemical characteristics and was successful. The liposome containing DTX reached an IC50 at a concentration of 65.74 nM in the PC3 cell line and 28.28 nM in the DU145 cell line. Immunoliposome, in turn, for PC3 cells reached an IC50 of 152.1 nM, and for the DU145 cell line, 12.60 nM, a considerable enhancement of cytotoxicity for the EGFR-positive cell line. Finally, the immunoliposome internalization was faster and greater than that of liposome in the DU145 cell line, with a higher EGFR overexpression. Thus, based on these results, it was possible to obtain a formulation with adequate characteristics of nanometric size, a high encapsulation of DTX and liposomes and particularly immunoliposomes containing DTX, which caused, as expected, a reduction in the viability of prostate cells, with high cellular internalization in EGFR overexpressing cells.

Stability of Ceftazidime Pentahydrate Investigated by Thermal Analysis Techniques

Cephalosporins are among the most frequently used broad-spectrum antimicrobial agents. Ceftazidime is a semisynthetic β-lactam antibiotic for parenteral administration widely used in the clinical practice, which has been categorized as a third-generation cephalosporin antibiotic. This drug crystallizes as a pentahydrate and, as all cephalosporins, it is unstable and subject to hydrolytic degradation. Taking this into account, this study investigates the stability under 2 different conditions (high temperature and exposition to vacuum) by using various techniques, as thermal analysis, Raman spectroscopy, and X-ray powder diffraction supported by multivariate curve resolution. It was proved that ceftazidime pentahydrate is unstable under the studied variables, exhibiting several transformation processes, which were discussed in terms of the crystalline structure.