New study from MD Anderson and BridgeBio's Navire Pharma shows SHP2 inhibition overcomes multiple therapeutic-resistance mechanisms in lung cancer

Preclinical data supports SHP2 inhibition as potential treatment strategy for overcoming osimertinib resistance

HOUSTON and SAN FRANCISCO ? New preclinical research from The University of Texas MD Anderson Cancer Center and BridgeBio Pharma, Inc. affiliate Navire Pharma, Inc., finds that the novel SHP2 inhibitor IACS-13909 is able to overcome multiple therapeutic-resistance mechanisms in non-small cell lung cancer (NSCLC), suggesting a possible new approach to treating cancers that have developed resistance to the targeted EGFR inhibitor osimertinib.

The data is published today in Cancer Research, a journal of the American Association for Cancer Research. IACS-13909, is a potent and selective allosteric SHP2 (Src homology 2 domain-containing phosphatase) inhibitor developed through collaboration between Navire and MD Anderson's Therapeutics Discovery division. Based on these data, Navire plans to launch a clinical study of SHP2 inhibitors by the end of 2020 at multiple US sites, including MD Anderson.

IACS-13909 was initially discovered as an SHP2 inhibitor by a team of scientists in MD Anderson's Institute for Applied Cancer Science (IACS) and Translational Research to Advance Therapeutics and Innovation in Oncology (TRACTION) platforms, both engines within the Therapeutics Discovery division.

"Tyrosine kinase inhibitors, like osimertinib, appear initially effective in suppressing tumor growth, but multiple mechanisms of resistance can develop while a patient is still receiving treatment," said Nancy Kohl, Ph.D., a senior author of the study and member of Navire's scientific advisory board. "This study shows that IACS-13909's ability to inhibit a protein downstream of multiple signaling pathways is a promising approach in overcoming these common tumor-resistance mechanisms."

Osimertinib is a targeted EGFR inhibitor used as a front-line option for treating patients with NSCLC harboring specific EGFR mutations. However, NSLCs frequently develop osimertinib resistance over time, either through additional mutations in EGFR that block activity of the drug, or by activating compensatory signaling pathways.

SHP2 is a protein that acts downstream in these pathways, and it is required for full activation of the MAPK signaling pathways, which is known to fuel tumor growth, proliferation and survival.

"Our findings show that IACS-13909 is capable of suppressing tumor cell proliferation in vitro and causing tumor regression in vivo for lung cancers harboring a variety of activated kinases as the oncogenic driver," said lead author Yuting Sun, Ph.D., co-project lead and senior research scientist with TRACTION at MD Anderson. "These data suggest that targeting SHP2 could provide a viable strategy for overcoming osimertinib resistance occurring through a variety of mechanisms."

These results were consistent when IACS-13909 was used as a single agent and in combination with osimertinib in vivo. The combination treatment in vitro led to prolonged, more durable responses in tumors that were sensitive to osimertinib and stimulated tumor regression in osimertinib-resistant models.

"Through our collaboration with the Therapeutics Discovery team at MD Anderson, we continue to uncover SHP2's critical role in activating multiple different pathways related to cancer's onset and growth," said Eli Wallace, chief scientific officer of oncology at BridgeBio, Navire's parent company. "This study further supports the very reason that Navire was founded - to develop novel SHP2 insights into targeted medicines for patients in need. We look forward to advancing our lead SHP2 inhibitor into the clinic later this year."

The ongoing research is supported by Navire through a global licensing and development agreement, and the Therapeutics Discovery division is supported in part by MD Anderson's Moon Shots Program®. MD Anderson has an institutional financial conflict of interest with Navire, and the research is managed according to MD Anderson's Institutional Conflict of Interest Management and Monitoring Plan. A complete list of study co-authors and their disclosures can be found with the full paper here.

About BridgeBio Pharma, Inc.

BridgeBio is a team of experienced drug discoverers, developers and innovators working to create life-altering medicines that target well-characterized genetic diseases at their source. BridgeBio was founded in 2015 to identify and advance transformative medicines to treat patients who suffer from Mendelian diseases, which are diseases that arise from defects in a single gene, and cancers with clear genetic drivers. BridgeBio's pipeline of over 20 development programs includes product candidates ranging from early discovery to late-stage development. For more information, visit bridgebio.com.

About Navire Pharma

Navire Pharma, a subsidiary of BridgeBio Pharma, and in collaboration with MD Anderson's Therapeutics Discovery division, is developing inhibitors of SHP2 as targeted therapeutics for the treatment of multiple cancers. Founded in 2017 with the aim of harnessing advances in understanding of SHP2 signaling to create novel targeted oncology medications, Navire is led by a team of veteran biotechnology executives. Together with patients and physicians, the company aims to bring safe, effective treatments to market as quickly as possible.

About MD Anderson

The University of Texas MD Anderson Cancer Center in Houston ranks as one of the world's most respected centers focused on cancer patient care, research, education and prevention. The institution's sole mission is to end cancer for patients and their families around the world. MD Anderson is one of only 51 comprehensive cancer centers designated by the National Cancer Institute (NCI). MD Anderson is ranked No.1 for cancer care in U.S. News & World Report's "Best Hospitals" survey. It has ranked as one of the nation's top two hospitals for cancer care since the survey began in 1990, and has ranked first 16 times in the last 19 years. MD Anderson receives a cancer center support grant from the NCI of the National Institutes of Health (P30 CA016672).