US drugmaker Pfizer has completed its takeover of rival Wyeth, combining both companies' operations under one health care firm.
The $68 billion deal was approved by European Union antitrust authorities in July.
Pfizer's vice-president of manufacturing in Ireland Dr Paul Duffy said the merger would "meaningfully advance" key strategic goals.
"It creates a company poised to be a leading biopharmaceutical company in a new era," he said.
"We are now a more diversified health care company, with products in human, animal and consumer health, including vaccines, biologics, small molecules and nutrition across developed and emerging markets. The combined company has a robust and growing pipeline of biopharmaceutical development projects in critical areas. Our pipeline in areas such as Alzheimer's disease, oncology, pain, neuroscience, diabetes and inflammation, will allow us respond more effectively to the unmet medical needs of patients around the world."
Pfizer has a number of operations in Ireland, more than $7 billion (€ 4.7 million) of capital investment has been put into its Irish operations. Some of its best-selling medicines are produced here, including Viagra.
The move makes the company the largest pharmaceutical employer in Ireland. Following the closure of the Wyeth takeover, Pfizer now has more than 5,000 employees across 13 locations in Cork, Dublin, Kildare, Limerick, and Sligo.
It is not yet known how the merger will impact jobs at the Irish divisions, but in January, Pfizer confirmed it would cut 19,000 jobs, about 15 per cent of the 129,500 employees it would have following the merger. This figure is in addition to more than 14,000 positions it has eliminated since 2007.
On a group-wide basis, the drugmaker has narrowed its drug-development focus to nine disease areas led by cancer, brain disorders and diabetes. It has trimmed its scientific programs on heart failure, high cholesterol and obesity. The New York-based company also reorganised its research centres so that each area of therapeutic research is based at one location.
EU regulators had raised concerns about comeptition in the animal health sector, leading Pfizer to propose divesting a number of vaccine areas, sedatives, antibiotics and parasiticides and oral rehydration salts. It also offered to divest Wyeth's manufacturing facility in Sligo.
"Pfizer's newly strengthened company will have some of the best assets, people, pipeline and capabilities in the industry," said Pfizer chief executive Jeffrey Kindler.
"We have a clear responsibility to turn those strengths into meaningful results for patients, customers and the communities we serve, as well as for our shareholders."
There is speculation that Pfizer may cut as much as $3 billion in research after combining its laboratories
with Wyeth. With the deal closed, Pfizer will probably trim its combined research budget, Martin Mackay, president of Pfizer Global Research and Development, said in an interview.
While Mr Mackay didn't say by how much, Pfizer may hold the line at about $8 billion, the same as it spent by itself in 2008, said Barbara Ryan, a Greenwich, Connecticut-based analyst for Deutsche Bank. That's 30 per cent less than the total both companies spent on research last year.
Analysts previously said the acquisition would help Pfizer diversify into vaccines and injectable biologic medicines, which are considered more immune to generic products than traditional pills.
Pfizer has trimmed jobs and limited the diseases it studies in the last two years to save money as it braces for
the loss of $10 billion in sales when its Lipitor cholesterol pill faces generic competition in 2011. While Mr Kindler said he bought Wyeth to help offset those losses, the drugmaker's ability to innovate over time may be diminished with fewer scientists to find new treatments, said Kenneth Kaitin, of Tufts University in Medford, Massachusetts.
"These big acquisitions don't do a thing for research," said Mr Kaitin, director of the Tufts Center for the Study of Drug Development. "I don't think anyone should be fooled into thinking these big acquisitions have anything to do with innovation or increased research and development capacity."
Additional reporting - Bloomberg