Abstract 1849: Developing a formulation of MDM2 inhibitor: Idasanutlin for enhanced stability, solubility, and anticancer activity in p53 sensitive lung cancer

Abstract Lung cancer is generally categorized into two major class, non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Both types chiefly disrupt the lung’s primary function of supplying oxygen to the body due to uncontrolled cell growth. Lung cancer metastasis is a major obstacle in controlling the prevalence of the tumor. One contributing factor is the over expression of MDM2 protein which inhibits the tumor suppressive effect of p53 protein, thereby fostering the proliferation and metastasis of NSCLC. To address this, we employed a second generation MDM2 inhibitor - Idasanutlin (IDA) to develop and characterize self-emulsifying nanocomplex of idasanutlin-ionizable lipid (IDLIN). IDA has demonstrated promising anticancer activity in vitro in p53 sensitive lung cancer cell lines. However, as a brick-dust molecule with poor solubility in both water and oil, it poses a significant challenge in development of lipid based nano formulation. We hypothesized that forming a hydrophobic complex between the carboxylic group of anionic IDA and the tertiary amine of DLin-DMA would improve the stability of IDA in water. The anticancer efficacy of this formulation was tested using various 2D and 3D cell culture assays in wild type p53 cells (A549 and H460). To formulate IDLIN, we used IDA along with Dimethyl Acetamide (DMA) as a cosolvent, DLin-DMA as the ionizable lipid, and 1:1 preconcentrate of oil and non-ionic surfactant. Medium Chain Triglycerides (MCT) served as oil, while Solutol HS 15 was used as surfactant. The inclusion of DMA and DLin-DMA significantly enhanced drug loading, achieving 3%w/w compared to 0.5%w/v in the conventional self-nanoemulsifying system. The observed particle size and zeta potential for IDLI (formulated with IDA, DMA, and MCT:HS15 without ionizable lipid) were 63.98nm and -30.7mV, respectively, whereas for IDLIN, the particle size and zeta potential were 71.69nm and -23.1mV, respectively. The in vitro anticancer efficacy of IDLIN was assessed against IDA dissolved in dimethyl sulfoxide at a concentration of 1 µM using a multicellular 3D spheroid assay. Both treatments resulted in a significant reduction in spheroid diameter and area compared to control group. By the end of the treatment, both groups also exhibited higher levels of red fluorescence compared to the control group, indicating a substantial increase in dead cells across both cell lines. In A549 cells, the treatment groups showed a decrease in spheroid area by 45.70% for IDA and 46.18% for IDLIN. In H460 cells, the decrease was 57.64% for IDA and 59.23% for IDLIN. The observed IC50 of IDA and IDLIN in A549 cells were 3.615µM and 4.766µM respectively and in H460 cells, 0.641µM and 0.707µM was respectively. This is the very first research in use of ionizable lipid in stabilizing anionic hydrophobic molecules and testing nano-formulation of MDMD2 inhibitor in lung cancer. Citation Format: Bhoomi Dholariya, Akanksha Patel, Henis Patel, Ketan Patel. Developing a formulation of MDM2 inhibitor: Idasanutlin for enhanced stability, solubility, and anticancer activity in p53 sensitive lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1849.