Panitumumab and pegylated liposomal doxorubicin in platinum-resistant epithelial ovarian cancer with KRAS wild-type: The PaLiDo study, a phase II nonrandomized multicenter study.
5052 Background: Ovarian cancer (OC) patients with platinum-resistant recurrent disease have few therapeutic options and the response rates are only 10-20% using non-cross-resistant chemotherapeutic agents. The increasing number of negative trials for OC treatment has prompted an evaluation of new biologic agents, which in combination with chemotherapy may result in improvement in survival. Panitumumab is a fully human monoclonal antibody specific to the epidermal growth factor receptor (EGFR). No previous studies have evaluated the effect of panitumumab in OC based on KRAS mutation status. The main purpose was to investigate the response rate in platinum-resistant, KRAS wild-type OC patients treated with pegylated liposomal doxorubicin (PLD) supplemented with panitumumab. Methods: Major eligibility criteria were confirmed stage I-IV primary epithelial ovarian/fallopian/peritoneal cancer patients with progression either during or within 6 months after end of first or second line platinum-based chemotherapy. Only patients with measurable disease by CA125 criteria and with KRAS wild type were eligible. Patients were treated with panitumumab 6 mg/kg day 1 and day 15 and with PLD 40 mg/m² day 1, every 4 weeks. Tumor assessment was performed at baseline and at every third cycle according to CA-125 criteria. Results: A total of 46 patients were enrolled by 6 study sites in this multi-institutional phase II trial. Within the population evaluable for response (N=33), there was 8 CA125 responders for an overall response rate of 24.3 %. Progression-free and overall survival in the intention-to-treat population (N=43) was 2.7 months (2.5-3.2 months, 95%CI) and 8.1 months (5.6-11.7 months, 95%CI), respectively. The most common treatment related grade 3 toxicities included skin toxicity (42%), fatigue (19%) and vomiting (12%). Conclusions: The combination of PLD and panitumumab demonstrates efficacy in platinum refractory/resistant patients although the dermatologic toxicity was considerable.