Promising Clinical Activity With Early Signs of Biologic Activity, Tolerability, and Durability
Clinical Response Reported With Single Agent CRi in AML
"We remain very encouraged by these early clinical data," said
There were no dose limiting toxicities identified. Grade 3 drug related events occurred in 16.7% (3/18) patients. No patients discontinued due to an adverse event. One patient achieved a complete response in the bone marrow with incomplete recovery of peripheral counts (CRi). In this patient, bone marrow blast counts steadily declined from a baseline count of 16% to less than 5% over the course of 8 cycles; the patient remains on therapy (316 days). Five of 18 efficacy-evaluable patients across dose levels remained on therapy for at least 4 cycles (12 weeks), and up to 14+ cycles (>10 months).
An additional recently enrolled patient achieved a rapid reduction in peripheral blasts from 30% at baseline to 3% on Day 20. As further indication of biological activity, peripheral blasts rose to 13% over two days upon discontinuation of CB-839 due to central nervous system disease progression. This patient was reported in the poster subsequent to the most recent safety data cut off.
In a preclinical study, CB-839 had anti-tumor activity in an AML cell line that was enhanced by addition of azacitidine (Vidaza), a standard of care therapy in the treatment of AML in elderly patients. A cohort of AML patients will be added to the clinical study utilizing this combination.
The data was presented at the meeting in a poster titled, "Phase I Study: Safety and Tolerability of Increasing Doses of CB-839, an Orally Administered Small Molecule Inhibitor of Glutaminase, in Acute Leukemia," by lead author
About Calithera Biosciences
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 clinical activity, tolerability and unique mechanism of action of CB-839. 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 Quarterly Report on Form 10-Q for the quarter ended
Jennifer McNealeyir@Calithera.com 650-870-1071