Introduction We evaluated the feasibility of combining arotinib with letrozole in the treatment of platinum resistant recurrent ovarian cancer; expecting to delay or inhibit the progress of this troublesome clinical problem, avoid hospitalization, and extend survival.

Methods This is a phase 2, single-arm, prospective study, we recruited patients with platinum resistant recurrent ovarian cancer at Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine (China). Treatment lasted for one year or stoped when disease progression/death/intolerable side effects occurred. The imaging evaluation of related lesions were conducted every three cycles, the size changes of measurable lesions were determined according to the RECIST 1.1 standard. The adverse reactions were classified into I-IV levels according to NCI-CTCAE 4.0 standards. This study was registered with ClinicalTrials.gov, number NCT04720807.

Results 28 patients were recruited and finally 24 patients were enrolled between Dec 16, 2020, and Mar 31, 2023. At the data cutoff date (Mar 31, 2023), 17 (70.83%) patients had completed the study, 7 (29.2%) patients was undergoing treatment. The ORR was 35% (95% CI 15.4–59.2) and DCR was 80% (95% CI 56.3–94.3) in the per population. The mPFS was 6.0 months (95% CI 3.79–8.21). There was no grade 4 adverse event, and the most common grade 3 adverse event was hypertension (6 [25%]), the main grade 1–2 adverse event included mucositis(6 [25%]), laryngitis (10 [41.7%]), et al. No treatment-related deaths were recorded.

Conclusion/Implications The combination of oral arotinib and letrozole was promising candidate for platinum resistant ovarian cancer, with apparent therapeutic effect and slight toxicities.