Two Pfizer Cancer Drugs Fail Trials

Pfizer has discontinued the Phase III trial A4021018 (ADVIGO 1018), which examined the investigational compound figitumumab (CP-751,871) in combination with erlotinib as a second/third-line treatment in patients with previously treated advanced non-adenocarcinoma non-small cell lung cancer (NSCLC). An independent Data Safety Monitoring Committee (DSMC) recommended the trial be stopped, concluding that the addition of figitumumab to erlotinib is unlikely to demonstrate a statistically significant improvement in the primary endpoint of overall survival compared to erlotinib alone.

Pfizer is continuing to study figitumumab in clinical trials for the potential treatment of prostate, breast and lung cancers, and Ewing’s sarcoma. Its first Phase III trial in NSCLC was cancelled when it was determined that adding the drug to carboplatin plus paclitaxel would not enhance overall survival compared to carboplatin plus paclitaxel alone.

Also, Pfizer’s two Phase III studies of Sutent (sunitinib malate) in advanced breast cancer did not meet their primary endpoints. The SUN 1064 study of sunitinib in combination with docetaxel for the first-line treatment of patients with advanced HER-2 negative breast cancer did not show a statistically significant improvement in progression-free survival compared with docetaxel alone. Also, the SUN 1099 study of sunitinib plus capecitabine, in previously-treated advanced breast cancer patients, did not show a statistically significant improvement in progression-free survival compared with capecitabine alone.

In addition, there were more adverse events, including serious adverse events, in the investigational arm than in the comparator arm of each study. A continuing analysis of efficacy and safety data will soon be completed and presented at a medical meeting.

Pfizer is continuing its development program for sunitinib, which includes Phase III trials for the potential treatment of other solid tumors including advanced NSCLC, advanced castration-resistant prostate cancer, advanced hepatocellular carcinoma, and as adjuvant therapy for renal cell carcinoma.