TESARO Announces Presentation of Rolapitant Pharmacokinetic (PK) Data at the MASCC/ISOO International Symposium


  • PK Data from Drug-Drug Interaction Study Describes Lack of CYP3A4 Interactions

BERLIN, June 28, 2013 (GLOBE NEWSWIRE) -- TESARO, Inc. (Nasdaq:TSRO), an oncology-focused biopharmaceutical company, today announced that results from a pharmacokinetic study of rolapitant, an NK-1 receptor antagonist, were presented this morning at the Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO) International Symposium in Berlin. These data support that rolapitant may be administered concomitantly with other pharmaceutical products that are metabolized by the liver microsomal enzyme CYP3A4, without a requirement for dose adjustment of the co-administered product. Pharmacokinetic data for other NK-1 receptor antagonists indicate that doses of concomitantly administered products metabolized by CYP3A4 must often be adjusted.

"We are pleased that these data contribute to a potential best-in-class profile for rolapitant, and believe that its long half life, potential to prevent significant nausea, and planned availability in both oral and intravenous formulations may help to differentiate it from competing agents," said Mary Lynne Hedley, Ph.D., President of TESARO.

An open-label drug-drug interaction study was conducted in 26 healthy subjects to evaluate the need for potential dose adjustments of drugs metabolized by cytochrome P450 3A4 (CYP3A4) that might be co-administered with rolapitant. Participants in this study received oral doses of midazolam, a sensitive CYP3A4 substrate, on Days 1, 3, 8 and 11 of the study, and received a single oral 200 milligram dose of rolapitant on Day 3. Serial blood samples were collected to enable measurement and comparisons of plasma levels of midazolam and its metabolite, 1-OH midazolam, over time.

Results demonstrated that administration of rolapitant had no effect on midazolam or 1-OH midazolam pharmacokinetics at any measured time point, including on Day 3, when rolapitant plasma levels reached peak concentrations. In addition, SCH 720881, the active metabolite of rolapitant, did not alter plasma levels of midazolam. Taken together, these results suggest that neither rolapitant, nor its active metabolite, are inhibitors or inducers of CYP3A4, the major isozyme involved in drug metabolism. Single oral doses of 200 milligrams of rolapitant were safe and well tolerated.

About Rolapitant

Rolapitant is a potent, highly selective, and long-acting NK-1 receptor antagonist that is currently being evaluated in Phase 3 trials for the prevention of chemotherapy-induced nausea and vomiting, or CINV. TESARO is investigating whether a single dose of rolapitant will significantly improve prevention of both nausea and vomiting during the 5-day at-risk period for cancer patients receiving emetogenic chemotherapy when administered along with the current standard of care (a 5-HT3 receptor antagonist plus a corticosteroid), as compared to the current standard of care alone.

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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