Long-term efficacy and safety of duloxetine in the management of painful chemotherapy induced peripheral neuropathy.
236 Background: Accordingly, Quality of life in the survivorship of patients with cancer is becoming one of the important issues with a development of systemic anticancer treatment. About 40% of the patients who receive chemotherapeutic agents which have neuropathic potential suffer from painful CIPN. Various approaches to relieve the pain associated with CIPN have been attempted in clinical practice. Previously duloxetine, a dual reuptake inhibitor of serotonin and norepinephrine, has been reported to reduce painful CIPN when administered for 5 weeks. We retrospectively investigated the effect of duloxetine on the pain associated with CIPN over a prolonged period of administration. Methods: Between December 2014 and December 2016, patients with advanced cancer who complained of CIPN during or after systemic chemotherapy were eligible. Initially, 30 mg of duloxetine was administered daily for the first week and 60 mg daily was administered from the second week thereafter. The severity of pain was evaluated using a numerical rating scale from 0 to 10. Study follow-up was performed at regular visits according to the chemotherapy schedule or at the time of evaluation of disease status in the patients who completed systemic chemotherapy. However, the patients were allowed to visit whenever needed. Results: Twenty-seven patients were evaluable, the median age was 64 years (range, 23-83 years), and 11 patients were male and 16 patients were female. Twenty-four of the 27 patients received neurotoxic chemotherapeutic agents such as cisplatin, oxaliplatin, taxane and vinca alkaloid. Patients receiving duloxetine showed a significant reduction in the pain intensity from baseline and the mean decrease in the average pain score was 2.85 (95% CI 2.26-3.44, P < 0.001). Twenty-five (92.5%) of the 27 patients showed decreased pain after the use of duloxetine. Mean duration of treatment was 29 weeks (range, 1~130 weeks). Median duration of response was 19 weeks (range, 4~99 weeks). Treatment-related adverse events were nausea (17.2%), vomiting (3.4%) and dizziness (6.8%). Conclusions: Duloxetine demonstrated a durable efficacy and tolerability for painful CIPN in patients with advanced cancer.