Merck KGaA to shutter Arklow site by 2028 as focus shifts to New Cork facility

Merck KGaA plans to close its production plant in Arklow, Ireland, by the end of 2028, marking a strategic pivot in its Irish operations and a loss of about 100 jobs. The decision follows a review of the company’s active pharmaceutical ingredient (API) portfolio, which it will discontinue at the site. Consultations with trade unions, including Ireland’s Services Industrial Professional and Technical Union, are set to begin immediately.

The Arklow facility, acquired in 2015 and operated under Merck Life Science, has long served as part of the company’s contract development and manufacturing organisation (CDMO) network. However, its closure coincides with Merck’s ongoing €440 million investment plan in Ireland, centred on expanding bioprocessing capacity.

Last month, Merck’s U.S. and Canadian brand, MilliporeSigma, inaugurated a €150 million filtration manufacturing facility in Cork, roughly 220 kilometres south of Arklow. 

The new 3,000-square-metre site will produce filtration systems vital to the development of monoclonal antibodies, vaccines, and cell and gene therapies. Alongside this, an expansion of Merck’s Carrigtwohill membrane production site in Cork is already underway, with completion targeted for 2027.

Despite Merck’s long-standing presence in Ireland, the restructuring underscores broader pressures on the German conglomerate. The company has faced trade uncertainty under shifting U.S. tariff policies and lowered its 2025 sales forecast for its life science division earlier this year. Leadership changes are also on the horizon, with CEO Belén Garijo set to step down by April 2026, succeeded by electronics head Kai Beckmann.

While the Arklow closure marks the end of one chapter, Merck’s continued investment in Cork signals its long-term commitment to Ireland’s life sciences sector.

Find out how Merck’s strategic realignment could reshape Ireland’s pharmaceutical landscape in the full story.