The maker of the powerful prescription painkiller OxyContin has reached a settlement of $270 million (£204m) with the state of Oklahoma, as the Sackler family behind the company faces mounting criticism over their role in the nation's deadly opioid crisis.

Purdue Pharma, owned by the Sackler family, was one of 13 drug manufacturers named in Oklahoma's lawsuit. The 12 remaining defendants, including Johnson and Johnson, still face trial in May.The family, known for their philanthropic work, have been lauded as patrons of the arts for decades, and the family name is emblazoned on the walls at many of the world's great museums and universities.

However, in the past few weeks, the Tate museums in London and the Guggenheim in New York have cut ties with the family. The National Portrait Gallery in London said last week that it will not proceed with a £1 million pledge from a charitable organisation overseen by some members of the Sackler family. Other institutions have also come under pressure to turn down donations or otherwise distance themselves from the Sacklers.

A Massachusetts court filing made public earlier this year found that family members were paid at least $4 billion from 2007 until last year, largely due to OxyContin.