LeonaBio

LeonaBio, formerly Athira Pharma, is a clinical-stage biopharmaceutical company developing small-molecule therapeutics for diseases with high unmet need in oncology and neurology, with operations based in Bothell, Washington. Its lead program is lasofoxifene, a nonsteroidal selective estrogen receptor modulator (SERM) licensed exclusively from Sermonix Pharmaceuticals for most global territories and developed as a targeted therapy for estrogen receptor-positive, HER2-negative, ESR1-mutated metastatic breast cancer; the ongoing Phase 3 ELAINE-3 trial is evaluating lasofoxifene in combination with the CDK4/6 inhibitor abemaciclib after progression on aromatase inhibitors and CDK4/6 inhibitors. The company's second clinical program, brelgometon (ATH-1105), is an orally available, brain-penetrant small molecule that positively modulates the neurotrophic HGF system and is being developed for amyotrophic lateral sclerosis following a completed first-in-human Phase 1 study in 80 healthy volunteers. LeonaBio reported a $19.0 million net loss for the second quarter of 2026 with $51.1 million in cash and investments, and had enrolled 495 of approximately 600 planned patients in ELAINE-3 as of that update. The company trades on the Nasdaq Capital Market under the symbol LONA.