(T1130-07-43) Vortioxetine-Loaded Liposomes: A Repurposed Approach for Glioblastoma Therapeutics

Purpose: Glioblastoma Multiforme (GBM) is one of the most complex and aggressive forms of cancer with a poor prognosis. It accounts for almost 30% of primary brain tumors and 80% of all malignant ones. The standard treatment for GBM usually involves surgery to remove as much of the tumor as possible, followed by a combination of radiation and chemotherapy, using Temozolomide (TMZ). Despite the current advancements in the treatment of GBM, patient outcomes remain overwhelmingly poor. Through a recent high-throughput screening study aimed at identifying re-purposeable neuroactive compounds with anti-glioblastoma potential, Vortioxetine (Vort) emerged as one of the top candidates demonstrating robust cytotoxicity against glioblastoma cells, and preclinical efficacy (1). Vortioxetine is a new-generation antidepressant with multimodal mechanisms of action, approved for managing major depressive disorder. However, its application in oncology, particularly for GBM, remains unexplored. Given Vortioxetine’s proven ability to cross the blood-brain barrier and its novel mechanism involving AP-1/BTG-driven tumor suppression (2), we aimed to formulate and evaluate vortioxetine-loaded liposomes to enhance drug delivery, improve therapeutic efficacy, and offer a promising alternative to existing GBM chemotherapies.

Methods: Vort-loaded liposomes were prepared using the conventional thin-film hydration method using 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and Cholesterol in a molar ratio of 7:3 with 10 mM total concentration. The lipids and drug (2 mg) were dissolved in Chloroform and Methanol in a 4:1 ratio (total volume 5 mL). The lipid solution was then subjected to a rotary evaporator for 2 hours under reduced pressure of 200 bars at 55°C at 35 rpm to achieve a thin film. After the film formation, it was hydrated with 2 mL Milli-Q water at the same temperature and rpm. The obtained suspension was further subjected to bath and probe sonication. It was then centrifuged for 3 minutes at 3,000 rpm at 4°C and the supernatant was collected to obtain the liposomes. The prepared formulation was characterized for particle size (nm), zeta potential (mV), and polydispersity index (PDI). To determine encapsulated drug content, a direct vesicle lysis technique was used, and a UV spectroscopic method was developed where Vortioxetine showed maximum absorbance at 237 nm. Solid State Characterization was carried out using the powder form of the liposomes obtained through freeze-drying liposomal formulations. Vort and Vort-Liposome, were evaluated for their cytotoxic potential in U87 GBM cancer cell line. The IC₅₀ (50% inhibitory concentration) values were calculated using the non-linear fitting module available in GraphPad Prism software.

Results: As shown in Figure 1, the particle size was found to be 146.2±69.4 nm, PDI of 0.2±0.07, and Zeta potential of 6.1±1.2 mV. A drug loading of 4.6±0.2% was achieved with a significant entrapment of 58.6±2.3% with 10 mM total lipid content.  DSC thermograms (Figure 2) revealed the disappearance of vortioxetine's characteristic melting peak (~120°C) in the Vort-loaded liposomes, indicating successful encapsulation within the lipid bilayer. In-vitro cytotoxicity studies against U87 glioblastoma cells showed IC₅₀ values of 9.7 µM for free vortioxetine and 13.08 µM for liposomal formulation. Current studies aim to further evaluate Vort-Liposomes for anti-GBM efficacy in 3D cell culture studies.

Conclusion: The current study highlights the potential of vortioxetine-loaded liposomes as a novel therapeutic approach for glioblastoma multiforme (GBM). While vortioxetine showed potential for GBM treatment, the reported dose of 10 mg/kg would result in a human equivalent dose (HED) of >56 mg/kg, 3-fold higher than the currently approved daily dose of vortioxetine. Encapsulation in liposomal carriers may not only enhance Vortioxetine’s anti-GBM efficacy, but may also enable localized accumulation by non-invasive administration, such as by the intranasal route. Further development will enable true and practical translation of vortioxetine into effective GBM therapy.

References: 1. Lee S, Weiss T, Bühler M, Mena J, Lottenbach Z, Wegmann R, et al. High-throughput identification of repurposable neuroactive drugs with potent anti-glioblastoma activity. Nat Med. 2024 Nov;30(11):3196–208.
2. Zhang H qi, Zhang D ming, Huang Z zhen, Cheng J, Zhang C, Lin N ming, et al. Vortioxetine exhibits anti-glioblastoma activity via the PI3K-Akt signaling pathway. Iran J Basic Med Sci. 2025;28(4):401–8.

Acknowledgements: The present work was supported by research funds provided to Vivek Gupta by College of Pharmacy and Health Sciences (CPHS), St. John’s University​
RS was supported by teaching assistantship from CPHS, Dept. of Pharmaceutical Sciences, St. John’s University​
All authors declare no conflict of interest in this work.


Figure 1 Formulation and Characterization


Figure 2 DSC thermogram


Figure 3 In-vitro cytotoxicity