Potential efficacy of weekly low-dose administration of bevacizumab as a combination therapy for platinum-resistant ovarian carcinoma: a retrospective analysis

BACKGROUND: Bevacizumab (Bev) plays the central role of the adjuvant therapy for patients with ovarian carcinoma. The aim of our study was to examine whether differences in the administration of Bev influence the prognosis of patients. METHODS: Patients with ovarian carcinoma who received treatment at two hospitals between 1999 and 2020 were identified. Patients treated with weekly low-dose administration of Bev (100 mg Bev on days 1 and 8 and 200 mg Bev on day 15, monthly) at one hospital (group A) and those with monthly high-dose administration of Bev (15 mg/kg of Bev on day 1, monthly) at another hospital (group B) were retrospectively compared. RESULTS: Among the total patients, 44 were assigned to group A and 33 were assigned to group B. More patients in group A had advanced disease (p = 0.03) and a lower dose of Bev at the first time during the first cycle administration (p < 0.01) than in group B. Progression-free survival (PFS) was better in group A than in group B (p < 0.01). Multivariate analysis revealed that group A was a better prognostic factor for PFS (hazard ratio 0.53, p = 0.03). Stable duration was longer in group A than in group B (p < 0.01). The incidences of adverse effects, including hematological toxicities such as neutropenia (p = 0.01) and nonhematological toxicities such as hypertension (p < 0.01), intestinal obstruction (p < 0.01), and thromboembolic events (p < 0.01), were lower in group A than in group B. CONCLUSIONS: Weekly low-dose administration of Bev might improve prognosis and decrease the frequency of adverse effects associated with this drug although the prospective study was needed to get corroboration.