Takeda Halts Development of Prostate Cancer Drug Orteronel
Treatment has no effect on overall survival
Takeda Pharmaceutical Company has decided to end the development program for orteronel (TAK-700) for the treatment of prostate cancer. The decision follows the results of two phase III clinical trials in men with metastatic, castration-resistant prostate cancer (mCRPC).
The studies found that while orteronel plus prednisone could extend the time patients lived before their cancer progressed, it did not extend overall survival in these patients.
After consideration of the data from these trials, the company determined that the drug has not demonstrated a clinical profile sufficient to move forward in mCRPC, given the availability of other therapies.
In May 2014, results were reported from the ELM-PC4 trial, a pivotal, international, double-blind, randomized phase III study in men with mCRPC who had not received chemotherapy. The data showed that orteronel plus prednisone improved radiographic progression-free survival (rPFS) compared with 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 OS.
Orteronel plus prednisone reduced the risk of rPFS by 30% compared with placebo plus prednisone in men with mCRPC (median rPFS: 11.0 vs. 8.3 months, respectively; P < 0.001). Median OS showed a numerical improvement of 1.9 months, which was not statistically significant, with orteronel plus prednisone versus placebo (median OS: 31.4 vs. 29.5 months, respectively; P = 0.314).
A previously reported phase III study, 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 OS compared with the control arm. The interim analysis did show an advantage for orteronel plus prednisone for the secondary endpoint of rPFS compared with the control arm.
There were no significant safety concerns in either study.
Orteronel is an investigational oral, nonsteroidal, selective inhibitor of 17,20-lyase, a key enzyme in the production of steroidal hormones, including androgens. The synthesis of androgens outside of the testes contributes to disease progression in men with CRPC.