Mirati Therapeutics Announces Initial Data In Renal Cell Carcinoma From Ongoing Investigator Sponsored Clinical Trial Of Sitravatinib In Combination With Nivolumab At The 2020 ASCO Genitourinary Cancers Symposium

News provided by

Feb 15, 2020, 11:30 ET

SAN DIEGO, Feb. 15, 2020 /PRNewswire/ -- Mirati Therapeutics, Inc. (NASDAQ: MRTX), a clinical stage targeted oncology company, today announced the presentation of initial data from an ongoing investigator sponsored Phase 1/2 clinical trial of sitravatinib in combination with nivolumab (OPDIVO^®) in patients with advanced clear cell renal cell cancer (aCCRCC) who have documented progression on a prior VEGF-targeted therapy. The data were presented today in an oral abstract presentation by Pavlos Msaouel, M.D., Ph.D., Assistant Professor, Department of Genitourinary Medical Oncology, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, at the 2020 ASCO Genitourinary Cancers Symposium in San Francisco, CA.

"The initial efficacy data from the Phase 1/2 clinical trial presented today demonstrates encouraging durable responses, when compared with progression-free survival rates expected with nivolumab alone in aCCRCC patients that progressed on prior VEGF-targeted therapy," said Charles M. Baum, M.D., Ph.D., President and Chief Executive Officer of Mirati. "These data indicate the potential range of extended clinical benefit beyond checkpoint refractory non-small cell lung cancer and metastatic urothelial cancer."

As of the data cut-off date of January 1, 2020, 38 out of 40 patients enrolled were evaluable for response at greater than 12 weeks on therapy:

15/38 (39%) patients achieved a confirmed partial response (PR) including one PR that has improved to an unconfirmed complete response (CR)
35/38 (92%) patients achieved clinical benefit (combination of stable disease plus PR plus CR)
Initial median progression-free survival (PFS) was 10.3 months
Median overall survival (OS) has not yet been reached (median follow-up was 17.7 months) with 30/38 patients (79%) still on study as of the data cut-off date.

The combination has been well-tolerated with manageable adverse events.

About Sitravatinib

Sitravatinib is a spectrum-selective kinase inhibitor that potently inhibits receptor tyrosine kinases (RTKs), including TAM family receptors (TYRO3, Axl, Mer), split family receptors (VEGFR2, KIT) and RET. As an immuno-oncology agent, sitravatinib is being evaluated in combination with nivolumab (OPDIVO^®), an anti-PD-1 checkpoint inhibitor, in patients whose cancers have progressed despite treatment with a checkpoint inhibitor. Sitravatinib's potent inhibition of TAM and split family RTKs may overcome resistance to checkpoint inhibitor therapy through targeted reversal of an immunosuppressive tumor microenvironment, enhancing antigen-specific T cell response and expanding dendritic cell-dependent antigen presentation.

About Mirati Therapeutics

Mirati Therapeutics (NASDAQ: MRTX) is a San Diego-based clinical-stage biotechnology company dedicated to advancing novel therapeutics that extend the lives of patients by directly addressing the genetic and immunological drivers of cancer. Mirati is developing sitravatinib, designed to selectively target a spectrum of tyrosine kinases implicated in both tumor growth and the suppression of immune responses to tumors. Sitravatinib has demonstrated durable responses in lung cancer patients whose cancer has progressed despite treatment with checkpoint inhibitors - an area of significant unmet medical need. Sitravatinib is being evaluated in multiple clinical trials to treat patients who are refractory to prior immune checkpoint inhibitor therapy, including a potentially registration-enabling Phase 3 trial of sitravatinib in combination with a checkpoint inhibitor in non-small cell lung cancer (NSCLC) that is currently enrolling patients.

Mirati is also developing novel inhibitors of KRAS mutations including MRTX849, a potent and selective inhibitor of KRAS G12C. This previously difficult to drug target is present in approximately 14% of NSCLC adenocarcinomas, 4% of colorectal cancer as well as smaller percentages of several other difficult-to-treat cancers. MRTX849 is being evaluated in a Phase 1/2 clinical trial as a treatment for patients with KRAS G12C-positive tumors. Our research on G12C has led to breakthroughs in targeting other KRAS mutations including G12D which drives tumor growth in more patients than G12C and includes pancreatic, colorectal and other types of cancer. For more information, visit www.mirati.com.

Forward Looking Statements

This press release contains forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995. Any statements in this press release regarding the business of Mirati Therapeutics, Inc. ("Mirati") that are not historical facts may be considered "forward-looking statements," including without limitation statements regarding Mirati's development plans and timelines, potential regulatory actions, the scope, timing and results of clinical trials, including without limitation the Phase 1/2 clinical study of sitravatinib in combination with nivolumab referenced above, and the potential benefits of and markets for Mirati's product candidates. Forward-looking statements are typically, but not always, identified by the use of words such as "may," "will," "would," "believe," "intend," "plan," "anticipate," "estimate," "expect," and other similar terminology indicating future results. Forward-looking statements are based on current expectations of management and on what management believes to be reasonable assumptions based on information currently available to them, and are subject to risks and uncertainties. Such risks and uncertainties may cause actual results to differ materially from those anticipated in the forward-looking statements. Such risks and uncertainties include without limitation potential delays in development timelines, negative clinical trial results, reliance on third parties for manufacturing and development efforts, changes in the competitive landscape, changes in the standard of care, as well as other risks detailed in Mirati's recent filings on Forms 10-K and 10-Q with the U.S. Securities and Exchange Commission. Except as required by law, Mirati undertakes no obligation to update any forward-looking statements to reflect new information, events or circumstances, or to reflect the occurrence of unanticipated events.

SOURCE Mirati Therapeutics, Inc.