Repurposing Drugs in Controlling Recurrent Platinum-Resistant Clear-Cell Ovarian Cancer

Background. Recurrent platinum-resistant clear-cell ovarian cancer has a low overall survival duration of 7-8 months, making it a fatal disease. Currently, chemotherapy is the major kind of treatment, but it offers little advantage. Repurposed conventional drugs have recently been found to offer the ability to control cancer with few side effects and at a reasonable cost to healthcare organizations. Case Presentation. In this case report, we present the case of a 41-year-old Thai female patient diagnosed with recurrent platinum-resistant clear-cell ovarian cancer (PRCCC) in the year 2020. After undergoing chemotherapy for two courses and failing to respond to treatment, she began alternative medicine with repurposing drugs in November 2020. Simvastatin, metformin, niclosamide, mebendazole, itraconazole, loratadine, and chloroquine were also administered. Two months after therapy, a computerized tomography (CT) scan revealed a conflict between a decline in tumor marker levels (CA 125, CA 19-9) and an increase in the number of lymph nodes. However, after continuing all medications for 4 months, the CA 125 level decreased from 303.6 to 54 U/ml, and the CA 19-9 level decreased from 1210.3 to 386.10 U/ml. The patient's EQ-5D-5L score increased from 0.631 to 0.829 (abdominal pain and depression), indicating improved quality of life. Overall survival was 8.5 months, and progression-free survival was 2 months. Conclusion. The response to drug repurposing is demonstrated by a four-month-long improvement in symptoms. This work introduces a novel strategy for the management of recurrent platinum-resistant clear-cell ovarian cancer that needs further evaluation in large-scale studies.