Phase 2 trial of tumor-targeted IL-12 with hepatic artery infusion pump therapy for colorectal liver metastases: interim analysis

A phase 2 trial at the National Cancer Institute (Bethesda, MD) evaluated the combination of tumor-targeted interleukin-12 (PDS01ADC) and hepatic artery infusion pump (HAIP) chemotherapy for patients with unresectable liver metastases from colorectal cancer previously treated with at least one line of systemic chemotherapy. Primary endpoints for a planned interim analysis were overall response rate and safety. The analysis included 9 patients. Seven patients (78%) had partial of complete responses at 6 months. The median hepatic progression-free survival was 12.7 months. Grade ≥ 3 toxicities occurred in 78% but were manageable and did not limit HAIP therapy. No patients developed a biliary stricture within 6 months of initiating treatment. Circulating immune markers and on-treatment bumor biopsies revealed enhanced immune activation following PDS01ADC. The authors conclude that addition of PDS01ADC is not detrimental to HAIP therapy and is associated with both systemic and intratumoral immune modulation.