Pfizer is reporting that a Phase III study evaluating Sutent in combination with erlotinib in advanced non-small-cell lung cancer (NSCLC) did not meet its primary endpoint of overall survival. The SUN 1087 trial was able to demonstrate a statistically significant improvement in progression-free survival (PFS), though, which was the secondary endpoint.
"Over the next few months we will conduct an in-depth analysis to gain further insight into these results and determine whether we can identify one or more subgroups of non-small-cell lung cancer patients for a future trial in either previously untreated or recurrent disease," says Mace Rothenberg, M.D., svp of clinical development and medical affairs for Pfizer's oncology business unit.
Sutent, an oral multikinase inhibitor, is currently approved for gastrointestinal stromal tumor (GIST) after disease progression on or intolerance to imatinib mesylate and advanced metastatic renal cell carcinoma (RCC). Pfizer continues to evaluate the potential role of Sutent as a treatment for advanced castration-resistant prostate cancer and as adjuvant therapy for renal cell carcinoma in Phase III trials.
Since April 2009, Sutent has failed to prove itself in five Phase III studies but did succeed in one. The first blow was to Pfizer’s advanced breast cancer program: Sutent as a single agent compared to capecitabine in patients who failed standard treatment as well as Sutent plus paclitaxel versus bevacizumab plus paclitaxel as a first-line treatment was found to not improve PFS.
In July 2009, the company halted its investigation of Sutent plus Folfiri versus Folfiri alone as a first-line treatment of metastatic colorectal cancer (CRC) because it found that a statistically significant improvement in PFS would not be achieved. And in March of this year Pfizer stopped two Sutent trials in advanced Her-2 negative breast cancer because of failure to improve PFS. The SUN 1064 Phase III study involved Sutent in combination with docetaxel as a first-line treatment, and the SUN 1099 Phase III study compared Sutent plus capecitabine in previously treated advanced breast cancer patients.
Pfizer’s sole success over the past year or so in expanding Sutent’s label came in June 2009. It reported that in a Phase III study, patients with advanced pancreatic islet cell tumors treated with the compound had a median PFS of 11.1 months compared to those on placebo who had a PFS of 5.5 months.
The most recent failure in NSCLS means that Pfizer’s late-stage pipeline of candidates for the treatment of lung cancers is now down to two: crizotinib, an oral anaplastic lymphoma kinase inhibitor, and PF-00299804, an irreversible, oral, selective pan-HER inhibitor. It also has Phase II candidates axitinib and PF-3512676 in development for lung cancer.