French healthcare group Sanofi has agreed to buy US haemophilia specialist Bioverativ for $11.6bn (€9.5bn), its biggest deal for seven years, which it said would strengthen its presence in treatments for rare diseases.

Pre-tax profits at one of the largest employers in the south-east, Genzyme last year soared by 35% to €68.5m.

Pre-tax profits at the Irish arm of global medical technology giant Genzyme last year increased by 5% to €50.56m as revenues topped €1.55bn.