CALA Calithera Biosciences Inc

Calithera Biosciences, Inc. (Nasdaq: CALA), a clinical stage biotechnology company focused on discovering and developing novel small molecule drugs for the treatment of cancer and other life-threatening diseases, announced new preclinical data for the company’s CD73 inhibitor CB-708. The data will be presented today at the American Association for Cancer Research (AACR) Annual Meeting 2019 in Atlanta, Georgia.

CB-708 is a selective, oral inhibitor of CD73, an enzyme that synthesizes the immunosuppressive agent adenosine and is over-expressed in multiple tumor types. By blocking adenosine production in the tumor, CB-708 is designed to enhance T-cell activation leading to anti-tumor activity. Calithera plans to initiate clinical development of the compound in the second half of 2019.

“We are excited to share these new preclinical data on CB-708, our small-molecule CD73 inhibitor designed to be dosed orally in patients, and to demonstrate our progress in advancing this compound into the clinic,” said Susan Molineaux, PhD, president and chief executive officer of Calithera. “CB-708 has the potential to be combined with immunotherapy or chemotherapy to activate the immune system and improve outcomes for patients with a variety of cancers.”

The preclinical data being presented today by Clarissa Lee, Ph.D. (Abstract #4134, Section 25, Board 8), demonstrate that CB-708 is a potent and selective inhibitor of CD73 that has immune-mediated, single agent activity in syngeneic mouse tumor models. In addition, in pre-clinical studies CB-708 is well-tolerated and shows enhanced anti-tumor activity when combined with either an anti-PD-L1 immunotherapy or with chemotherapeutic agents such as oxaliplatin or doxorubicin.

Additional meeting information can be found at the AACR website www.aacr.org. The CB-708 poster presentation will be available at www.calithera.com on the Publications page.

About CB-708 and CD73

CB-708 is an orally bioavailable small molecule inhibitor of CD73, an enzyme in the tumor microenvironment that produces adenosine, a powerful inhibitor of immune function in tumors. CD73 is expressed across a wide range of tumor types and tumor-infiltrating leukocytes. Expression of CD73 often correlates with poor prognosis in patients with cancer. Blockade of adenosine production by CD73 inhibition is expected to reverse immunosuppression in the tumor microenvironment and enhance the immune system’s ability to fight the cancer.

About Calithera

Calithera is a clinical-stage biopharmaceutical company focused on fighting cancer and other life-threatening diseases by discovering, developing, and commercializing novel small molecule drugs that target tumor and immune cell metabolism. Calithera is headquartered in South San Francisco, California. For more information about Calithera, please visit www.calithera.com.

Forward Looking Statements

Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as "may," "will," "expect," "anticipate," "estimate," "intend," "poised" and similar expressions (as well as other words or expressions referencing future events, conditions, or circumstances) are intended to identify forward-looking statements. These statements include those related to the timing of Calithera’s clinical trials, the review, registration and approval of CB-708 by the FDA, and the safety and efficacy of CB-708. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. The potential product candidates that Calithera develops may not progress through clinical development or receive required regulatory approvals within expected timelines or at all. In addition, clinical trials may not confirm any safety, potency or other product characteristics described or assumed in this press release. Such product candidates may not be beneficial to patients or successfully commercialized. The failure to meet expectations with respect to any of the foregoing matters may have a negative effect on Calithera's stock price. Additional information concerning these and other risk factors affecting Calithera's business can be found in Calithera's periodic filings with the Securities and Exchange Commission at www.sec.gov. These forward-looking statements are not guarantees of future performance and speak only as of the date hereof, and, except as required by law, Calithera disclaims any obligation to update these forward-looking statements to reflect future events or circumstances.

SOURCE: Calithera Biosciences, Inc.

CONTACT: Jennifer McNealey

ir@Calithera.com

650-870-1071