TESARO Announces Presentation of Niraparib Data at the 2016 IGCS Biennial Meeting

WALTHAM, Mass., Oct. 31, 2016 -- TESARO, Inc. (NASDAQ:TSRO), an oncology-focused biopharmaceutical company, today announced the presentation of data from the ENGOT-OV16/NOVA trial of niraparib at the 2016 International Gynecologic Cancer Society (IGCS) Biennial Meeting in Lisbon, Portugal. These data were presented on Sunday, October 30 during the Best Oral session by Dr. Ursula Matulonis, M.D., Medical Director of the Gynecologic Oncology Program at Dana-Farber Cancer Institute and principal investigator on the ENGOT-OV16/NOVA trial, during the Best Oral session. The results were previously published in the New England Journal of Medicine on October 8, 2016 and presented at the ESMO 2016 Congress.

“Many women with recurrent ovarian cancer experience a fear of recurrence in between regimens of platinum-based chemotherapy. The availability of an oral maintenance treatment that could lengthen the progression free survival interval between rounds of platinum-based chemotherapy with a tolerable side effect profile could be very empowering for patients,” said Dr. Matulonis. “The data from ENGOT-OV16/NOVA are extremely encouraging and demonstrate the potential of niraparib to offer a meaningful benefit for our patients with ovarian cancer.”

“We are grateful for the patients, their families, and the caregivers that participated in the ENGOT-OV16/NOVA study, and we would like to thank our partners at ENGOT for their diligence in executing this trial,” said Mary Lynne Hedley, Ph.D., President and COO of TESARO. “We believe the results of this Phase 3 study demonstrated a meaningful benefit for women with platinum sensitive, recurrent ovarian cancer. We are pleased that the EMA recently accepted for review the MAA for niraparib, and we are on track to complete the rolling NDA submission imminently.”  

ENGOT-OV16/NOVA is a double-blind, placebo-controlled, international Phase 3 trial of niraparib that enrolled 553 patients with recurrent ovarian cancer who were in response to their most recent platinum-based chemotherapy. This trial was designed to assess progression free survival (PFS) in a broad population of patients who were assigned to one of two cohorts based upon germline BRCA mutation status. The ENGOT-OV16/NOVA trial successfully achieved its primary endpoint in both cohorts, demonstrating that niraparib treatment significantly prolonged PFS compared to control in patients who were germline BRCA mutation (gBRCAmut) carriers and in patients who were not germline BRCA mutation (non-gBRCAmut) carriers. A high proportion of patients in both treatment groups in both cohorts had received three or more prior lines of chemotherapy.

The most common (≥10%) treatment-emergent grade 3/4 adverse events in the niraparib arm were thrombocytopenia (33.8%), anemia (25.3%), and neutropenia (19.6%) with treatment discontinuation for these events of 3.3%, 1.4% and 1.9%, respectively. Thrombocytopenia was not associated with grade 3/4 bleeding events. The majority of these hematological laboratory abnormalities occurred within the first three cycles; following dose modifications the incidence of these lab abnormalities decreased and thrombocytopenia and neutropenia were infrequent beyond cycle 3. The rates of MDS/AML in the niraparib (1.4%) and control (1.1%) arms were similar. There were no deaths among patients during study treatment.

About the Phase 3 ENGOT-OV16/NOVA Clinical Trial of Niraparib
ENGOT-OV16/NOVA is a double-blind, placebo-controlled, international Phase 3 trial of niraparib that enrolled 553 patients with recurrent ovarian cancer who were in a response to their most recent platinum-based chemotherapy. Patients were enrolled into one of two independent cohorts based on germline BRCA mutation status. One cohort enrolled patients who were germline BRCA mutation carriers (gBRCAmut), and the second cohort enrolled patients who were not germline BRCA mutation carriers (non-gBRCAmut) and included patients with HRD-positive and HRD-negative tumors. Within each cohort, patients were randomized 2:1 to receive niraparib or placebo and were treated continuously with placebo or 300 milligrams of niraparib, dosed as three 100 milligram tablets once per day, until progression. The primary endpoint of this study was progression-free survival (PFS). Secondary endpoints include patient-reported outcomes, chemotherapy-free interval length, PFS 2, overall survival, and other measures of safety and tolerability.  More information about this trial is available at http://clinicaltrials.gov/show/NCT01847274.

About Niraparib
Niraparib is an oral, once-daily PARP inhibitor that is currently being evaluated in four ongoing pivotal trials. TESARO is building a robust niraparib franchise by assessing activity across multiple tumor types and by evaluating several potential combinations of niraparib with other therapeutics. The ongoing development program for niraparib includes a Phase 3 trial in patients with platinum-sensitive, recurrent ovarian cancer (the NOVA trial); a Phase 3 trial in patients with first-line ovarian cancer (the PRIMA trial); a registrational Phase 2 treatment trial in patients with ovarian cancer (the QUADRA trial); and a Phase 3 trial for the treatment of patients with BRCA-mutant breast cancer (the BRAVO trial). Several combination studies are also underway, including trials of niraparib plus pembrolizumab and niraparib plus bevacizumab. Janssen Biotech has licensed rights to develop and commercialize niraparib specifically for patients with prostate cancer worldwide, except in Japan.

The U.S. Food and Drug Administration (FDA) has granted Fast Track designation to niraparib for the treatment of patients with recurrent platinum-sensitive ovarian, fallopian tube, or primary peritoneal cancer. TESARO has initiated a rolling submission of a New Drug Application (NDA) for niraparib to the FDA, and intends to complete this submission during the fourth quarter. The Marketing Authorization Application (MAA) for niraparib has been submitted to and accepted for review by the European Medicines Agency (EMA) for the maintenance treatment of patients with platinum-sensitive, recurrent ovarian cancer who are in response to platinum-based chemotherapy.

Niraparib is an investigational agent and, as such, has not been approved by the U.S. FDA, the European Medicines Agency (EMA), or any other regulatory agencies.

About Ovarian Cancer
Approximately 22,000 women are diagnosed each year with ovarian cancer in the United States, and more than 65,000 women are diagnosed annually in Europe. Ovarian cancer is the fifth most frequent cause of cancer death among women. Despite high response rates to platinum-based chemotherapy in the second-line advanced treatment setting, approximately 85% of patients will experience recurrence within two years. If approved, niraparib may address the difficult “watchful waiting” periods experienced by patients with recurrent ovarian cancer in between cycles of platinum-based chemotherapy.

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 in this release 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 expectations with respect to regulatory submissions and 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. 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 Annual Report on Form 10-K for the year ended December 31, 2015, and its Quarterly Report on Form 10-Q for the quarter ended June 30, 2016.

Investor/Media Contact:
Jennifer Davis
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