TESARO Initiates Phase 3 Trial of Niraparib for Treatment of Patients With Ovarian Cancer

First Patient Enrolled in the NOVA Study


WALTHAM, Mass., July 23, 2013 (GLOBE NEWSWIRE) -- TESARO, Inc. (Nasdaq:TSRO), an oncology-focused biopharmaceutical company, today announced that it has initiated patient enrollment in a Phase 3 trial of niraparib, an inhibitor of poly ADP-ribose polymerase (PARP), for the treatment of ovarian cancer. This trial, referred to as NOVA, will evaluate a single daily 300 milligram dose of niraparib in 360 patients with high grade serous, platinum sensitive, relapsed ovarian cancer compared to placebo.

"We are pleased to open this Phase 3 trial of niraparib to patients with ovarian cancer," said Mary Lynne Hedley, Ph.D., President of TESARO. "This milestone represents a significant advance in the progression of TESARO's pipeline and brings us closer to our goal of delivering new oncology therapies to patients."

Final results from a Phase 1 trial of niraparib were presented on June 4 at the American Society of Clinical Oncology (ASCO) annual meeting in Chicago. These data showed that at the recommended dose, 75% (three of four patients) with platinum sensitive high grade serous ovarian cancer (HGSOC) achieved a RECIST response. Across all dose levels (30 milligrams to 400 milligrams daily), a RECIST response rate of 46% (6/13 patients) was observed in this population. A RECIST response rate of 50% (5/10 patients) was achieved in patients with platinum sensitive ovarian cancer and germline BRCA mutations. The median duration of response was 431 days for platinum sensitive germline BRCA patients and 444 days for platinum sensitive patients who were not germline BRCA mutation carriers. The patients with ovarian cancer who were enrolled in this study had received a median of six previous regimens of systemic therapy. Niraparib was generally well tolerated at 300 milligrams daily, with a low rate of grade 3/4 toxicities. The most frequently observed adverse events at the 300 milligram dose included grade 1/2 anemia, fatigue and nausea.

About The NOVA Study

The NOVA (Niraparib Ovarian) study is a double blind, placebo-controlled, international Phase 3 trial of niraparib is planned to enroll 360 patients with high grade serous, platinum sensitive, relapsed ovarian cancer. Patients will enroll into one of two independent cohorts based on germline BRCA mutation status. Within each cohort, patients will be randomized 2:1 to receive niraparib or placebo, and will be continuously treated with placebo or 300 milligrams of niraparib until progression. The primary endpoint of this study is progression free survival. Secondary endpoints include patient reported outcomes, chemotherapy free interval length, and overall survival. More information about this Phase 3 trial is available at http://clinicaltrials.gov/show/NCT01847274.

About TESARO

TESARO is an oncology-focused biopharmaceutical company dedicated to improving the lives of cancer patients by acquiring, developing and commercializing safer and more effective therapeutics. For more information, visit www.tesarobio.com.

To the extent that statements contained in this press release are not descriptions of historical facts regarding TESARO, they are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Words such as "may," "will," "expect," "anticipate," "estimate," "intend," and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. Forward-looking statements involve substantial risks and uncertainties that could cause our clinical development programs, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, the uncertainties inherent in the initiation of future clinical trials, availability of data from ongoing clinical trials, expectations for regulatory approvals, and other matters that could affect the availability or commercial potential of our drug candidates. TESARO undertakes no obligation to update or revise any forward-looking statements. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the business of the Company in general, see TESARO's Form 10-K for the year ended December 31, 2012.



            

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