Pfizer has marked its first foray into Ireland 50 years ago. The US multinational, one of the first to arrive in the country, initially made citric acid at a plant in Ringaskiddy.

“Now we manufacture complex medicines for cancer, infectious disease, inflammation and stroke prevention from our six Irish sites,” said Mike McDermott, president of Pfizer Global Supply, who is in Ireland this week to mark the anniversary.

Pfizer has grown from 16 staff back in those early days to a workforce of more than 3,700 people in 2019, and is recruiting again.

"Outside of the US, our Irish operations are substantial and we are proud of our Irish workforce who play an important role in getting innovative medicines to patients in over 100 countries around the world," said Mr McDermott, who visited the company's original Irish site in Ringaskiddy in Cork, and also nearby Little Island yesterday. He will travel to the pharma group's other Irish sites over coming days.