Original sentence: Criticism of Vertex pricing structures for Orkambi, a groundbreaking cystic fibrosis drug costing in the region of  to  per patient per year depending on the patient's country, has resulting in campaigns by concerned parent groups addressed to Leiden.Leiden encountered media attention in 2015 due to the level of compensation he received from Vertex in 2014, reportedly in the region of.Leiden wrote to the UK Prime Minister Theresa May in 2018, suggesting Vertex might consider reducing investment in the UK as a result of the lack of agreement between Vertex and the UK's National Health Service on the pricing of a five-year access agreement for Vertex drugs.Vertex shareholders opted to reduce CEO compensation in 2015 and 2016, resulting in 2016 earnings of  for Leiden