Randomized phase II trial of a toll-like receptor 9 agonist oligodeoxynucleotide, PF-3512676, in combination with first-line taxane plus platinum chemotherapy for advanced-stage non-small-cell lung cancer.

Abstract

This study assessed the efficacy of the combination of standard taxane plus platinum chemotherapy with the synthetic Toll-like receptor 9-activating oligodeoxynucleotide PF-3512676 in patients with non-small-cell lung cancer (NSCLC). Chemotherapy-naive patients with stage IIIB to IV NSCLC were randomly assigned (one to two ratio) to receive four to six cycles of taxane/platinum chemotherapy alone or with 0.2 mg/kg of subcutaneous PF-3512676 on days 8 and 15 of each 3-week cycle. The primary end point was objective response rate (ORR). Baseline demographics were similar between treatment arms, although significantly more patients in the PF-3512676 arm had stage IV disease (85% compared with 62% in the chemotherapy-alone arm). The modified intent-to-treat analysis (n = 111) demonstrated a 38% ORR (confirmed and unconfirmed) in the PF-3512676 arm (n = 74) and 19% in the chemotherapy-alone arm (n = 37) by investigator evaluation. Blinded, independent radiologic review for 90 patients showed a similar trend in confirmed response rate (19% and 11%, respectively). Median survival was 12.3 months in the PF-3512676 arm and 6.8 months in the chemotherapy-alone arm, and 1-year survival was 50% and 33%, respectively. Mild to moderate local injection site reactions and flu-like symptoms were the most common PF-3512676-related adverse events, but grade 3/4 neutropenia, thrombocytopenia, and anemia were all reported more commonly for patients in the PF-3512676 arm. The addition of PF-3512676 to taxane plus platinum chemotherapy for first-line treatment of NSCLC improves objective response and may improve survival. Confirmatory phase III trials are ongoing.