Utidelone-based therapy in advanced or metastatic solid tumors after failure of standard therapies: a prospective, multicenter, single-arm trial

Treatment options are limited for tumors after failure of standard therapies. Utidelone (UTD1), a novel microtubule stabilizer, given via 5 days intermittent infusion, has demonstrated high activity in heavily pretreated metastatic breast cancer, while its efficacy in other cancers was unclear. Peripheral neuropathy is a common and severe adverse event (AE) of UTD1. We performed a prospective, multicenter, single-arm trial (ChiCTR2300074299) to evaluate the efficacy and safety of UTD1 with a changed administration mode in patients with advanced or metastatic solid tumors after failure of standard therapies. UTD1 (150 mg/m², alone or in combination with other anticancer agents) was administrated via 120 h continuous intravenous infusion every 21 days until disease progression or intolerable toxicity. A total of 50 patients were enrolled and analyzed, including 20 breast cancer patients, 11 gynecological cancer patients, 8 gastrointestinal cancer patients, 6 lung cancer patients, and 5 patients with other solid tumors. The overall median progression-free survival (PFS) was 4 months, the overall objective response rate and disease control rate were 20% and 66%, respectively, and the median overall survival was not reached. Most of the AEs were grade 1 or 2 and were manageable and reversible, the rate of grade ≥3 AEs including peripheral neuropathy was 4%. This study demonstrated a promising anti-tumor activity of UTD1 in patients with advanced or metastatic solid tumors after failure of the standard therapies. Moreover, 120 h continuous intravenous infusion was a more tolerable administration mode than 5 days intermittent infusion, and worthy of further study.