The lack of OS advantage is the reason for the discontinuation.
Takeda Pharmaceutical Company Limited (TSE:4502) announced today that it has voluntarily decided to end the development program for orteronel (TAK-700) for prostate cancer. The decision follows the results of two Phase 3 clinical trials in metastatic, castration resistant prostate cancer (mCRPC). The studies found while orteronel plus prednisone could extend the time patients lived before their cancer progressed, it did not extend overall survival in these patients. After careful consideration of the data from these trials, the company has determined that the drug has not demonstrated a clinical profile sufficient to move forward in mCRPC, given the availability of other therapies.
On May 14, 2014, Takeda announced results from ELM-PC4, a pivotal, international, double blind, randomized Phase 3 trial in men with mCRPC who had not received chemotherapy, which showed that orteronel plus prednisone improved radiographic progression free survival (rPFS) compared to prednisone alone, one of the study’s two primary endpoints, but did not show a statistically significant improvement in the study’s second primary endpoint of overall survival (OS). A previously reported Phase 3 trial, ELM-PC5, in men with mCRPC that had progressed during or following chemotherapy, was unblinded in 2013 after a pre-specified interim analysis indicated that orteronel plus prednisone would likely not meet the primary endpoint of improved overall survival when compared to the control arm. The interim analysis did show an advantage for orteronel plus prednisone for the secondary endpoint, radiographic progression-free survival over the control arm. There were no significant safety concerns in either study.