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ARTICLE | Clinical News

Oncothyreon off after Phase II data for PX-866

May 17, 2013 1:32 AM UTC

Oncothyreon Inc. (NASDAQ:ONTY) fell $0.64 (25%) to $1.97 on Thursday after reporting data from two Phase II trials of once-daily oral PX-866 to treat recurrent glioblastoma multiforme (GBM) and recurrent or metastatic castration-resistant prostate cancer (CRPC). In 33 evaluable patients with GBM at first recurrence after chemoradiation and adjuvant temozolomide, PX-866 missed the primary endpoint of objective response rate (ORR). The six-month progression-free survival (PFS) rate in the open-label trial was 17%. In the second trial, PX-866 in a six-week cycle missed the primary endpoint of lack of disease progression at week 12 in 43 patients with recurrent or metastatic CRPC not previously treated with docetaxel.

The National Cancer Institute of Canada Clinical Trials Group (NCIC-CTG) sponsored both trials. Data are to be presented at the American Society of Clinical Oncology meeting in June. PX-866, an oral phosphoinositide 3-kinase (PI3K) inhibitor, is also in Phase I/II testing to treat melanoma and colorectal cancer. Oncothyreon said it does not plan to move forward with development of PX-866 for GBM. ...