A phase II/III study comparing intravenous ZD9331 with gemcitabine in patients with pancreatic cancer.

ZD9331 is a novel antifolate inhibitor of thymidylate synthase (TS). This multicentre, randomised, phase II/III study compared the efficacy and safety of ZD9331 with gemcitabine in 55 patients with chemonai;ve, locally advanced or metastatic pancreatic cancer. Patients received intravenous (i.v.) ZD9331 (n=30), on days 1 and 8 of a 3-week cycle or i.v. gemcitabine (n=25), once a week for 7 weeks followed by a 1-week rest, then on days 1, 8 and 15 of a 4-week cycle. Objective tumour response and clinical benefit response (CBR) were similar for both groups. More ZD9331 patients were alive at the data cut-off point compared with gemcitabine patients (13 and 8%, respectively). Median survival (152 versus 109 days, respectively) and time to progression (70 versus 58 days, respectively) were longer in the ZD9331 group. Nausea and vomiting (grade 1/2) were the most common toxicities in both groups. These results suggest that, in pancreatic cancer, ZD9331 is equivalent to gemcitabine and may offer a promising alternative to current therapies.