Takeda announces updated results from orteronel phase 2 study on nmCRPC

Millennium: The Takeda Oncology Company with its parent company Takeda Pharmaceutical Company Limited (TSE:4502) today announced updated results from a phase 2 study of orteronel, a selective oral 17,20 lyase inhibitor, dosed without prednisone in patients with non-metastatic castration resistant prostate cancer (nmCRPC) and rising prostate-specific antigen (PSA). These data were presented in a poster discussion session at the annual meeting of the American Society of Clinical Oncology (ASCO), held June 1-5 in Chicago, Illinois.    

"Non-metastatic castration resistant prostate cancer is an area of unmet need, and therapies that reduce PSA without the need for concomitant corticosteroids are of particular interest in these earlier lines of prostate cancer treatment," said Daniel George, M.D., Duke University Medical Center.

"We are encouraged by the results with orteronel in non-metastatic prostate cancer," said Karen Ferrante, M.D., Chief Medical Officer, Millennium. "These data support the continued evaluation of orteronel in a steroid free regimen."

Safety and activity of the investigational agent TAK-700 (orteronel) without prednisone in men with nonmetastatic castration-resistant prostate cancer (nmCRPC) and rising prostate-specific antigen (PSA): Updated results of a phase 2 study (Abstract #4549)

The primary objective of this study was to determine the percentage of patients achieving a PSA reduction to ≤ 0.2 ng/mL (undetectable levels). Patients with PSA values of 0.2ng/mL or less have been shown to have a greater survival advantage. Secondary objectives were to determine the safety of orteronel, PSA response rates at 3 months and 6 months (decline in PSA of ≥ 90 percent, ≥ 50 percent and/or ≥ 30 percent), the percentage of patients achieving a PSA reduction to ≤ 0.2 ng/mL after 6 months, time to PSA progression, time to metastases, duration of progression-free survival, and changes in endocrine markers.

Results from the study of 39 patients, which were presented by Dr. George, showed:

• 16 percent of patients experienced PSA < 0.2 ng/mL at three months, and 12 (32%) experienced PSA < 0.2 ng/mL as their best response
• 32 percent experienced a decline in PSA of ≥ 90 percent at 3 months 23 (61%) experienced a decline in PSA of ≥ 90 percent as their best response
• 76 percent experienced a decline in PSA of ≥ 50 percent at 3 months, and 84 percent experienced a decline in PSA of ≥ 50 percent as their best response
• Median time to PSA progression was 14.8 months
• With a median follow-up of 7 cycles (8.3 months), only three patients developed metastatic disease; freedom from metastases was 97 percent at 6 and 12 months, and median time to metastases was not reached
• Orteronel dosed without prednisone suppressed testosterone by 87-89 percent and the adrenal androgen DHEA by 85-89 percent
• The most common adverse events were fatigue (62 percent), diarrhea (38 percent); and hypertension (38 percent)
• The most common adverse events of grade 3 or higher were hypertension (15 percent); dyspnea (8 percent); and fatigue, hypokalemia and pneumonitis (each 5 percent)

Eligible pts had nmCRPC with PSA ≥ 2 ng/mL (PSA ≥ 8 ng/mL if doubling time > 8 mo), and surgical/medical castration, with testosterone (T) <50 ng/dL. Prior chemotherapy or ketoconazole, and concomitant corticosteroids were excluded. Starting dose of TAK-700 was 300 mg BID and continued until PSA progression, metastases, or unacceptable toxicity.    

Source: Takeda Pharmaceutical Company Limited