A phase I trial of intraperitoneal recombinant gamma-interferon in advanced ovarian carcinoma.

The interferons are a class of biological agents that have demonstrated antineoplastic activity in a variety of tumors both in vitro and in vivo. Previous reports have suggested that interferons can be safely administered by the intraperitoneal (IP) route with a pharmacokinetic advantage for peritoneal cavity exposure compared with the systemic circulation and with objective antitumor activity being demonstrated. On the basis of these reports and laboratory data suggesting activity for recombinant gamma-interferon (r-GIFN) against several malignant cell lines, we treated 27 refractory ovarian carcinoma patients, including six with very-small-volume residual disease, with this agent delivered by the IP route. While r-GIFN was found to be remarkably well tolerated, with a 150- to 200-fold pharmacokinetic advantage for peak levels achieved in the peritoneal cavity compared with the plasma, no objective responses were observed. Despite the lack of demonstrated activity for single-agent IP-administered r-GIFN in this clinical setting, there remains considerable interest in this agent when delivered by the IP route because of in vitro data suggesting concentration-dependent synergy between r-GIFN and other biological agents.