Neurocrine Biosciences agreed to acquire Soleno Therapeutics for $2.9 billion, adding Soleno’s marketed Prader-Willi syndrome therapy Vykat XR to Neurocrine’s endocrinology and rare disease portfolio. The all-cash deal values Soleno at $53 per share, a premium highlighted by analysts given Vykat XR’s revenue momentum. Vykat XR (diazoxide choline) is the first and only approved treatment indicated for hyperphagia in patients age four and older with Prader-Willi syndrome. Soleno reported $190.4 million in 2025 net revenue from Vykat XR, including $91.7 million in Q4, supporting profitability. The transaction would complement Neurocrine’s existing marketed assets, including Crenessity for classic congenital adrenal hyperplasia and Ingrezza for tardive dyskinesia and chorea associated with Huntington’s disease. Analysts characterized the price and timing as somewhat unexpected, increasing scrutiny on growth trajectory and safety as the franchise scales.