Pharma giant Pfizer expects to submit plans for a major expansion of its Grange Castle plant this week that is likely to see several hundred jobs created at the west Dublin site.
The announcement will be the first major investment to be unveiled since the Brexit referendum result. There had been concern about the impact of that vote on investment in Ireland and other European Union states.
The former Wyeth facility is already one of the largest biotechnology plants in the world and an important biopharmaceutical site for the company.
It produces some of Pfizer’s biggest drugs, including the arthritis blockbuster Enbrel and the vaccine Prevenar, which is used in children to prevent pneumococcal infections .
The US group is looking to build a new five-storey biopharma manufacturing unit in two phases, adding more than 34,500sq m to its current footprint.
The development will also include a warehouse facility, new laboratory space and other works, along with the provision of 565 new car park spaces. Close to 300 of those will replace existing spaces lost with the new development.
The company confirmed it intends to apply to South Dublin County Council for planning permission for a "potentially significant expansion" of the Clondalkin operation.
“The planning approval is being sought to prepare for potential expansion which is contingent upon the continued successful clinical development of investigational compounds in Pfizer’s mid and late stage pipeline,” it said.
Grange Castle has already seen investment of $1.8 billion and employs about 1,100 people. The 90-acre site has seen several rounds of expansion since it first opened in 2005.
Originally commissioned by biopharma group Wyeth before that company’s acquisition by Pfizer in 2009, it was first extended in 2007.
In 2011, Taoiseach Enda Kenny announced plans for a $200 million investment and, in 2013, the company invested a further $100 million with a new production line to cope with demand for Enbrel.
Pfizer was recently frustrated by the Obama administration in the US in its efforts to engineer a $160 billion corporate inversion with Irish-domiciled Allergan that would have seen its corporate headquarters move to Dublin, sharply cutting its exposure to US taxes.
In the wake of new treasury rules that rendered the deal unviable, group chief executive Ian Read said Pfizer was being impeded from investing in the US because of onerous tax rules on repatriated profits.
“We can invest less because of a broken tax system,” he said.
The company employs about 3,300 people in Ireland across seven sites in Cork, Kildare, Dublin, Sligo.
Pfizer , which has had a presence in Ireland since 1969, has said it intends to seek a 10-year permission for the development.