Shares of Enliven Therapeutics (NASDAQ:ELVN) climbed 7% on Thursday after the company released positive early results from a Phase 1b study of its chronic myeloid leukemia (CML) drug candidate, ELVN-001.
Enliven said patients enrolled in the ongoing randomized Phase 1b cohorts achieved a major molecular response (MMR) rate of 53% by 24 weeks. Across all study cohorts, the cumulative MMR rate reached 69%, while deep molecular responses were recorded in 35% of patients in the randomized groups.
The findings are notable given the heavily pretreated nature of the study population, with more than half of participants—53%—having previously received four or more tyrosine kinase inhibitors (TKIs). Enliven added that ELVN-001 continued to show a favorable safety and tolerability profile at all dose levels tested, in line with earlier results.
“Our data continue to demonstrate that ELVN-001 has the potential to be the best-in-class active-site TKI for the treatment of CML and an important treatment option across all lines of therapy,” said Helen Collins, Chief Medical Officer of Enliven.
Looking ahead, the Boulder, Colorado–based company outlined several planned milestones for 2026, including a mid-year presentation of additional Phase 1 data, discussions with the U.S. Food and Drug Administration on dose selection, and the start of a Phase 3 clinical trial in the second half of the year.
ELVN-001 is engineered to selectively target the BCR::ABL gene fusion, the primary oncogenic driver in CML. The drug demonstrated strong clinical activity at once-daily doses ranging from 60 mg to 120 mg, with no clear dose-response relationship observed within that range.