Phase II study of intraperitoneal submicron particle paclitaxel (SPP) plus IV carboplatin and paclitaxel in patients with epithelial ovarian cancersurgery

Submicron particles (~800 nm) of paclitaxel (SPP) contain 1–2 billion molecules of pure drug that release tumoricidal levels of paclitaxel over many weeks. This study compared two dose-levels of SPP instilled into the peritoneal cavity (IP) in 200 ml of saline post-cytoreductive surgery. Eligible patients with primary (n = 6) or recurrent (n = 4) epithelial ovarian cancer who underwent complete cytoreductive surgery were enrolled to receive a single instillation of IP SPP followed by standard IV carboplatin and paclitaxel. Endpoints were PFS and evaluation of treatment emergent adverse events. Clinical response was determined by symptoms, physical exams, CT scans, and serum CA-125 measurements. Of the 24 subjects screened, 10 were enrolled and received treatment: seven patients received 100 mg/m² and three received 200 mg/m². Seven subjects completed the 12-month follow-up period. Six patients were evaluable due to one subject who had unevaluable scans throughout the follow-up period and was thus excluded from PFS determination. Upon completion of planned chemotherapy post-SPP instillation, the PFS at 6 months was 66% (4/6) and at 12-months 66% (4/6) using RECIST 1.1. One subject had a complete response at the end of IV treatment but died (unrelated to study treatment) before PFS evaluation. There was one case of incision dehiscence and one case of vaginal cuff leakage after surgery. This pilot study supports further evaluation of IP SPP to treat peritoneal carcinomas.