Why Did Calithera Shares Dropped To 52-Week Low In Premarket Friday?

Calithera Biosciences Inc (NASDAQ:CALA) has decided to terminate its phase 2 KEAPSAKE trial based on a lack of clinical benefit observed in patients treated with telaglenastat in an interim analysis.
The Phase 2 KEAPSAKE study was designed to evaluate the safety and anti-tumor activity of telaglenastat plus standard-of-care chemo-immunotherapy as front-line therapy for stage IV non-squamous non-small cell lung cancer (NSCLC) harboring KEAP1 or NRF2 mutation.
At the time of unblinding on October 27, there were 40 patients randomized.
The available efficacy data did not demonstrate clinical benefit, and analysis of the data concluded that there was a very low probability for the study to achieve a positive result.
No difference in safety profile was seen between the two arms.
Calithera estimates the cost savings resulting from the discontinuation of this trial will be $10-15 million.
Related: Calithera Buys Two Oncology Candidates From Takeda For $45M.
Price Action: CALA shares are down 43.70% at $1.07 during the premarket session on the last check Friday.