Up to 300 new jobs are being created in Cashel in Co Tipperary.
US generic drugs giant Amneal has purchased the former Johnson and Johnson plant on the Cahir Road.
Amneal's Irish operations will be dedicated to research and development as well as the production of inhalers and biosimilars - all high-end specialty medications.
The 200,000 square foot former Johnson & Johnson plant in Cashel has lain idle for a number of years, but it now has a new lease of life with US company Amneal taking over the site.
Amneal expects to hire an estimated 250 to 300 employees.
The Jobs Minister Richard Bruton has described the announcement, which is supported by the IDA, as a massive boost for Cashel and the whole of Tipperary.