Abstract Ovarian cancer is projected to claim approximately 13,000 lives in the United States in 2025. Current treatment options remain limited and often insufficiently effective, underscoring the need for alternative therapeutics that may improve survival outcomes. To explore such possibilities, we screened two anti-parasitic drugs: ivermectin (IV) and fenbendazole (FZ). These drugs have been reported to exhibit anti-cancer properties. Both drugs were tested on the ovarian cancer cell lines SKOV3 and ES-2 using a luminescence-based CellTiter-Glo cell viability assay kit (Promega). Previous studies indicate that these compounds can inhibit proliferation and promote apoptosis in some cancer cell lines and mouse xenograft models. FZ in particular has been reported to alter the expression of MYC, a gene involved in cancer cell growth, proliferation, and survival. Using the open-access cancer database, we retrieved data from The Cancer Genomic Atlas and found that high MYC expression in ovarian cancer patients significantly correlates with decreased survival (p = 0.044). Our cell viability assays revealed cell line-dependent anti-proliferative responses. ES-2 cells displayed a clear dose-dependent decrease in viability following IV or FZ treatment, whereas SKOV3 cells were comparatively less sensitive. For ES-2, IV at 8, 4, 2, and 1 μM doses at 48-hour post-treatment, yielded viabilities of 0.88%, 4.91%, 18.82%, and 78.97%, respectively; for SKOV3, the corresponding viabilities were 8.92%, 56.62%, 76.61%, and 100.0%. FZ produced a similar trend: ES-2 viabilities at 5, 2.5, 1.25, and 0.625 μM were 6.97%, 27.02%, 50.52%, and 69.46%, while SKOV3 viabilities were 17.32%, 19.46%, 20.49%, and 50.54%, respectively. IC50 calculations further highlighted these differences. In SKOV3, the IC50 for FZ (1.02 μM) was lower than that for IV (3.678 μM). In ES-2, both drugs produced similar IC50 values (IV: 2.5345 μM; FZ: 2.3285 μM). These findings suggest the potential anti-cancer activity of these anti-parasitic agents and further testing their efficacy as therapeutic candidates for ovarian cancer. Our laboratory is currently investigating the combination therapies involving these drugs with standard chemotherapeutics and other agents shown to modulate MYC and other emerging anti-cancer compounds to improve treatment efficacy for ovarian cancer patients. Citation Format: Aneth Ochoa Negrete, Tiffany Duque, Adithi Kankanala, Gisel Gutierrez, Riyaz Basha. Evaluation of anti-parasitic agents as potential therapeutics in ovarian cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7103.
Negrete et al. (Fri,) studied this question.