The Company	6 Months Ended
Jun. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	1. THE COMPANY Alkermes plc is a global biopharmaceutical company that seeks to develop innovative medicines in the field of neuroscience. Alkermes has a portfolio of proprietary commercial products for the treatment of alcohol dependence, opioid dependence, schizophrenia and bipolar I disorder and a pipeline of clinical and preclinical candidates in development for neurological disorders, including narcolepsy and idiopathic hypersomnia. Headquartered in Ireland, Alkermes also has a corporate office and research and development (“R&D”) center in Massachusetts and a manufacturing facility in Ohio. In May 2024, the Company completed the sale of its research and development business and manufacturing facility in Athlone, Ireland (the “Athlone Facility”) to Novo Nordisk (“Novo”). The Company and Novo also entered into subcontracting arrangements to continue certain development and manufacturing activities performed at the Athlone Facility for a period of time after the closing of the transaction, which activities may continue through the end of 2025. In connection with the sale of the Athlone Facility, the Company received approximately $97.9 million from Novo, which included a payment of approximately $91.0 million for the facility and certain related assets, and recorded a gain of approximately $1.5 million within “Other income, net” in the accompanying condensed consolidated statements of income and comprehensive income for the three and six months ended June 30, 2024.

The Company

6 Months Ended

Jun. 30, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

1. THE COMPANY

Alkermes plc is a global biopharmaceutical company that seeks to develop innovative medicines in the field of neuroscience. Alkermes has a portfolio of proprietary commercial products for the treatment of alcohol dependence, opioid dependence, schizophrenia and bipolar I disorder and a pipeline of clinical and preclinical candidates in development for neurological disorders, including narcolepsy and idiopathic hypersomnia. Headquartered in Ireland, Alkermes also has a corporate office and research and development (“R&D”) center in Massachusetts and a manufacturing facility in Ohio.

In May 2024, the Company completed the sale of its research and development business and manufacturing facility in Athlone, Ireland (the “Athlone Facility”) to Novo Nordisk (“Novo”). The Company and Novo also entered into subcontracting arrangements to continue certain development and manufacturing activities performed at the Athlone Facility for a period of time after the closing of the transaction, which activities may continue through the end of 2025. In connection with the sale of the Athlone Facility, the Company received approximately $97.9 million from Novo, which included a payment of approximately $91.0 million for the facility and certain related assets, and recorded a gain of approximately $1.5 million within “Other income, net” in the accompanying condensed consolidated statements of income and comprehensive income for the three and six months ended June 30, 2024.