Alkermes Plc said Monday it has agreed to acquire the privately held biopharmaceutical company Rodin Therapeutics for an upfront cash payment of $100 million and another up to $850 million in milestone payments. Dublin-based Alkermes said the deal will expand its presence in central nervous system treatments. Rodin is developing therapeutics for synaptopathies by designing molecules that target specific histone deacetylase (HDAC) complexes, the companies said in a statement. Synaptic dysfunction is a feature in many neurogenerative diseases and neuropsychiatric diseases, such as Alzheimer's disease, Huntington's disease, frontotemporal dementia and depression. "Rodin's targeted approach to strengthening synaptic integrity is backed by a robust translational strategy and may have potential across multiple diseases which are characterized by impaired neuronal and synaptic function," Chief Executive Adam Rosenberg said in the statement. Alkermes will work to advance Rodin's research and expects to incur about $20 million of r&d costs in 2020. The company will provide financial expectations for 2020 in February. The company will fund the upfront payment using cash on hand and account for its as an R&D expense. The deal is expected to close by the end of November. Alkermes shares were not yet active premarket, but have fallen 29% in 2019, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.48% has gained 24%.