Effectiveness of taxanes following nivolumab in patients with advanced esophageal squamous cell carcinoma: a retrospective chart review of patients in ATTRACTION-3

Background The phase III ATTRACTION-3 study showed that second-line nivolumab monotherapy for advanced esophageal squamous cell carcinoma prolonged overall survival (OS) but did not improve progression-free survival (PFS). Subsequent systemic therapy after discontinuing nivolumab may affect these outcomes. To test this possibility, we evaluated the outcomes of treatment with taxanes after nivolumab in ATTRACTION-3. Methods We reviewed the charts of Japanese patients who had discontinued second-line nivolumab in ATTRACTION-3 and started subsequent third-line taxanes between January 7, 2016, and November 12, 2018. The primary endpoint was objective response rate (ORR) to third-line taxanes. Results Of the 75 patients included in this study, 54 (72%), 18 (24%), and 3 (4%) patients received either paclitaxel, docetaxel, or combination therapy comprising docetaxel, cisplatin, and 5-fluorouracil, respectively. The ORR in the overall, paclitaxel, and docetaxel groups was 29.6%, 36.5%, and 12.5%, respectively; these numbers were comparable to those (20-44%) in patients receiving taxanes as first- and second-line therapy. The median OS in the overall, paclitaxel, and docetaxel groups was 9.9, 9.9, and 9.3 months, respectively, whereas the corresponding median PFS was 4.9, 4.7 and 6.5 months, respectively. Treatment-related adverse events were observed in 65 (87%) patients, of which grade 3-4 occurred in 37 (49%) patients. Conclusions Favorable effectiveness and safety profile of taxanes following second-line nivolumab was observed in Japanese patients with advanced esophageal squamous cell carcinoma. When a patient with advanced esophageal squamous cell carcinoma receiving nivolumab becomes refractory or intolerant, subsequent taxane treatment may be a promising option.