Pfizer is cutting 177 jobs at production plants in Cork, Ireland, where the company's cholesterol drug Lipitor is produced.
Lipitor, the highest selling medicine in the world with sales of around $14bn a year, lost patent protection in Europe in May 2012 and in the US in November 2011, threatening a significant portion of the drug's earning potential.
As a result, the company is seeking to reduce the losses associated with the patent expiry, cutting approximately €80m ($100.7m) from its operations in Ireland. Pfizer has confirmed that the job cuts have been prompted by reduced production volume.
Workers at the two sites, located in Little Island and RIngaskiddy, will take redundancy in 2013.
As Pfizer loses patent protection for Lipitor and other medications, persistent rumours have linked the company with a major cost reduction programme. Pfizer has already announced its intention to spin off non-core business units as part of company refocus.
Pfizer vice president Paul Duffy explained that the company had been preparing for the looming patent expiry for a considerable time.
"Patent expiry means greater competition, which impacts global demand, and we need to readjust the scale of our manufacturing operations," added Duffy.
Pfizer currently employs around 4,000 people across eight sites in Ireland and, despite the redundancies, Paul Duffy confirmed the company's commitment to Ireland.
"Ireland remains a key strategic location for Pfizer, we have multiple sites located in Cork, Kildare, Limerick and Dublin, with diverse operations in pharmaceutical active ingredient manufacturing, tableting, biopharmaceutical manufacturing, as well as treasury, shared services and commercial operations," said Duffy.
Image: Pfizer's world headquarters, located in New York, US. Photo courtesy of: Norbert Nagel.