Pfizer will cut 177 jobs in Ireland following the expiration of patents on blockbuster cholesterol drug Lipitor, highlighting the exposure of Ireland's export-driven economy to the patent cliff facing many in the pharmaceutical sector.

Eight of the world's top 10 pharmaceutical companies operate in Ireland. The sector employs around 25,000, according to business lobby group IBEC, and last year produced €26 billion ($32 billion) worth of products, representing 28% of total goods exported.

But many top pharmceutical group face a wave of patent expiries in the next few years and are struggling to find lucrative replacements, leaving their staff exposed to cutbacks.

"Patent expiry means greater competition which impacts global demand and we need to readjust the scale of our manufacturing operations," Pfizer Vice President Paul Duffy said in a statement on Wednesday.

Pfizer is to make the cuts at three sites next year. It employs approximately 4,000 people at eight sites in Ireland and has invested $7 billion in operations since 1969.

Bailed out by the EU/IMF in late 2010 and midway through a punishing eight-year austerity drive, Ireland has an unemployment rate of 14.3%, its highest since 1993 and more than three times the level of 2007.