LeonaBio, Inc. (formerly Athira Pharma, Inc.) has acquired exclusive global development and commercialization rights to lasofoxifene, a selective estrogen receptor modulator (SERM) for metastatic breast cancer, from Sermonix Pharmaceuticals, Inc. (excluding Asia and certain Middle East countries). The acquisition is supported by an upfront private placement financing of $90 million, with warrants providing up to an additional $146 million upon exercise, totaling up to $236 million. The financing is co-led by Commodore Capital, Perceptive Advisors, and TCGX, with participation from several other investors, and is expected to provide capital runway into 2028. Lasofoxifene is currently in the ongoing Phase 3 ELAINE-3 clinical trial (NCT05696626), which is over 50% enrolled, with topline data expected in the second half of 2027. The ELAINE-3 study protocol is being amended to increase the sample size from 500 to up to 600 participants to ensure sufficient disease progression events, with enrollment expected to complete in Q4 2026. LeonaBio expects to incur approximately $45 million in cash expenditures for the ELAINE-3 Study in 2026 and $30 million in 2027, significantly increasing the pace and intensity compared to Sermonix's prior efforts. As part of the transaction, LeonaBio will issue a pre-funded warrant to Sermonix and is obligated to make up to $100 million in milestone payments and tiered royalties on net sales. LeonaBio has also assumed $16,815,728.00 in Sermonix liabilities and provided initial advances of $311,531.43, with monthly advances of $75,000 to follow, all creditable against future payments.