Last month, the US drug giant MSD announced that it was adding 100 new jobs to its Carlow workforce through a major new manufacturing plant at the site. The company said the move would help expand production of modern biologics drugs for the treatment of cancers and would be in addition to the 2,800 people that it already employs in Ireland. MSD, which is known as Merck in North America, is one of the top six drug companies worldwide in terms of sales. In Ireland, it operates at five sites – Carlow, Ballydine in Co Tipperary, Brinny in Co Cork,…