Benzinga | Jan 4, 2021 07:08AM EST

Calithera Biosciences Reports CANTATA Study Of Telaglenastat In Renal Cell Carcinoma Did Not Achieve Primary Endpoint; Co. To Reduce Workforce By ~35%

-- Company will continue to advance telaglenastat KEAPSAKE trial in non-small cell lung cancer,

arginase inhibitor CB-280 trial in cystic fibrosis and emerging pipeline

-- Company to host webcast and conference call today at 8:30 a.m. ET / 5:30 a.m. PT

SOUTH SAN FRANCISCO, Calif., Jan. 04, 2021 (GLOBE NEWSWIRE) -- 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, today announced topline results from the CANTATA clinical study of the company's glutaminase inhibitor telaglenastat in patients with advanced or metastatic renal cell carcinoma (RCC). As compared to treatment with cabozantinib, the combination of telaglenastat and cabozantinib did not meet the primary endpoint of improving progression free survival (PFS) in the study population.

The primary study endpoint is PFS by blinded independent review. The hazard ratio was 0.94 (p=0.65). Median PFS was 9.2 months among patients treated with telaglenastat and cabozantinib as compared to 9.3 months with cabozantinib and placebo. Sixty-two percent of patients were treated with prior PD(L)-1 containing therapy, and the arms were well balanced. The frequency and severity of adverse events in the telaglenastat-treated population were comparable to that of cabozantinib alone.

"We are disappointed that the CANTATA trial did not achieve its primary endpoint, particularly on behalf of the people living with advanced RCC, many of whom could benefit from additional treatment options with novel mechanisms of action to address this difficult-to-treat disease," said Susan Molineaux, PhD, president and chief executive officer of Calithera. "Based on the strong scientific rationale for telaglenastat in KEAP1/NRF2 mutant non-small cell lung cancer patients, and the safety profile observed in CANTATA, we remain dedicated to advancing our randomized KEAPSAKE trial."

Calithera will focus its financial resources on the ongoing KEAPSAKE trial, the ongoing trial of the arginase inhibitor CB-280 in cystic fibrosis patients and pipeline programs. As a result of the outcome of CANTATA, Calithera will reduce its workforce by approximately 35 percent to allow the company to focus on ongoing programs.

Calithera expects cash, cash equivalents and investments to be approximately $115 million at December 31, 2020 based on preliminary estimates, which management believes will be sufficient to meet its current operating plan through 2022, including the release of interim results of the KEAPSAKE trial and completion of the current cystic fibrosis study in 2021. Calithera anticipates the one-time severance-related charge associated with the workforce reduction to be approximately $1.3 million - $1.5 million, with the majority to be completed by the first quarter of 2021. More financial details will be provided by the company in its fourth quarter 2020 financial report in March 2021.

The information relating to cash, cash equivalents and investments is preliminary, has not been audited and is subject to change upon completion of the audit of Calithera's financial statements as of and for the year ended December 31, 2020.

The CANTATA trial (NCT03428217) is a global, randomized, double-blind trial designed to evaluate the efficacy and safety of telaglenastat in combination with cabozantinib versus placebo with cabozantinib in patients with advanced or metastatic RCC who have been treated with one or two prior lines of systemic therapy, including at least one vascular endothelial growth factor (VEGF)-pathway targeted anti-angiogenic therapy or the combination of nivolumab and ipilimumab. The CANTATA trial enrolled 444 patients at multiple centers globally. Exelixis, Inc. provided cabozantinib for the trial through a material supply agreement with Calithera.

Calithera will submit the CANTATA results for presentation at a medical meeting.