The Justice Department on Wednesday (Oct. 10) approved the $69 billion merger of CVS Health Corporation and Aetna, two of the largest companies in the prescription drug market, but Aetna must sell its Medicare Part D plans that cover 1.5 million people to WellCare Health Plans , and Aetna may not sell new Medicare drug plans in 2020. Consumer advocates warned that allowing the nation’s largest retail pharmacy chain (CVS) and the third-largest health-insurance company (Aetna) to merge could hurt...