Rep. Keith Ellison (D-Minn.) questioned the appointment of CVS Caremark vice president and former Pfizer executive Daniel Best to oversee HHS drug pricing reforms in a letter to Secretary Alex Azar.

In his letter, Ellison noted price hikes at Pfizer during Best’s tenure and said his time at the company was “marked by the company working to keep patients on its more expensive branded cholesterol drug despite the availability of a cheaper generic.”

“Given Mr. Best’s career working for the pharmaceutical and pharmacy industry, the decision to hire him poses significant potential for conflicts of interest, placing him in a position to make decisions that may pit the income of his former employers against the interests of patients in reducing prescription drug prices,” Ellison wrote.