VYNE shares surge 58.80% after-hours after announcing merger with Yarrow Bioscience and securing $200M in funding.

VYNE Therapeutics Inc. surged 58.80% in after-hours trading following the announcement of a definitive merger agreement with Yarrow Bioscience. The all-stock transaction will form a combined entity focused on advancing YB-101, a clinical-stage TSHR antibody for Graves’ disease and thyroid eye disease, with $200 million in pre-closing financing to fund operations through 2028. The merger, approved by both boards, includes a $14.5–$16.5 million cash dividend to VYNE shareholders and positions the company to initiate a U.S. Phase 1b/2b trial for YB-101 in 2026. The deal, expected to close in Q2 2026, provides Yarrow with a path to commercialize YB-101 globally while leveraging VYNE’s capital and infrastructure, driving optimism among investors.