The settlement is expected to drive down patients' out-of-pocket costs for drugs such as insulin by up to $7 billion over 10 years.

Physician leaders warn that without protections, insurers' new policies could add administrative and financial burdens, threatening patient care.

About half of physicians reported their patients sought medications through compounding pharmacies or by traveling abroad.

The nation’s three primary insulin manufacturers (Eli Lilly, Novo Nordisk and Sanofi) and three largest PBMs (CVS Caremark, Express Script and OptumRx) are named in the lawsuit.