Ireland is "overwhelmingly likely" to host a third manufacturing facility for Botox.
Allergan CEO Brent Saunders made the forecast in an exclusive interview with the Irish Independent as he this week oversaw the official opening of the €145m Biologics 2 facility at Allergan's manufacturing facility in Westport, Co Mayo.
"We're beginning to scratch our heads and thinking about a third site for Botox. And that will overwhelmingly likely be in Ireland," Mr Saunders said.
"Botox is arguably the most recognised biopharmaceutical brand in the world," he said. "It's in the echelon of brands like Coke and Pepsi and Apple."
Allergan opened its first Irish facility in 1977 in Westport and started making Botox there in 1995. Today its Westport campus employs 1,500, including 200 contractors. Two robotics-assisted lines produce Botox from bulk neurotoxin delivered by private jet from California.
The Biologics 2 facility, officially opened on Tuesday, also greatly expands the space available for research and development of potential new products using strains of the botulinum toxin.
Mr Saunders, Allergan's CEO since 2015, will step down from the role later this year once its $63bn (€57bn) merger with Chicago-based AbbVie closes. AbbVie says it will continue to promote Botox and other cosmetic treatments in a separate division retaining the Allergan name.
"Ireland would be the perfect host if you had to open another facility," said Mr Saunders, who will join the AbbVie board.
"Our experience there over 40 years has overwhelmingly proved how important Ireland is and how wonderful the IDA is, the Government is, the communities are, and most importantly how wonderful the talent is."
As Westport's second Botox production line became fully operational, he said, "you have to start thinking about your third facility".
"If we had to open a third facility, I would strongly advocate and strongly believe it should be in Ireland."
Ms Saunders stressed that no decision had been taken, only that such a move in the medium term would be logical.
He said AbbVie - which already employs 700 people on five sites across Ireland - would strengthen the combined company's ability to invest in R&D and new products.
And he said Ireland - with third-level courses producing steady supplies of graduates primed for pharma careers - meant the enlarged AbbVie should be just as committed to Ireland.
"Ireland is our home, Ireland is a huge part of who Allergan is, and it will remain an important part of who AbbVie is.
"Westport will continue to be the centrepiece of Allergan's operations. It really is the crown jewel of our operations. Westport is clearly a big piece of our history and an important part of our legacy.
"But most importantly, it's a very important investment opportunity for us in the future."
Mr Saunders said Botox is far and away Allergan's most important product with annual sales of around $3.5bn.
It's also one of its fastest-growing products, with sales up by 60pc since 2014.
He says brand awareness surveys have found that more than 90pc of people worldwide have heard of Botox.